In Brazil, the jackfruit can become an invasive species as in Brazil's Tijuca Forest National Park in Rio de Janeiro or at the Horto Florestal in neighbouring Niterói. The Tijuca is mostly an artificial secondary forest, whose planting began during the mid-nineteenth century; jackfruit trees have been a part of the park's flora since it was founded.
The species has expanded excessively because its fruits, which naturally fall to the ground and open, are eagerly eaten by small mammals, such as the common marmoset and coati. The seeds are then dispersed by these animals, spreading jackfruit trees that compete for space with native tree species. The supply of jackfruit has allowed the marmoset and coati populations to expand. Since both prey opportunistically on bird eggs and nestlings, the increases in marmoset and coati populations are detrimental to local birds.


Arum maculatum is a woodland flowering plant species in the family Araceae. It is native across most of Europe, as well as Turkey and the Caucasus. It is known by an abundance of common names including Adam and Eve, adder's meat, adder's root, arum, wild arum, arum lily, bobbins, cows and bulls, cuckoopint, cuckoo-plant, devils and angels, friar's cowl, jack in the pulpit, lamb-in-a-pulpit, lords-and-ladies, naked boys, snakeshead, starch-root, and wake-robin. Many names refer to the plant's appearance; "lords-and-ladies" and many other names liken the plant to male and female genitalia symbolising copulation. Starch-root is a simple description – the plant's root was used to make laundry starch.
Lords and ladies is a very common plant and not considered at threat.


The leaves of A. maculatum appear in the spring (April–May) and are 7 to 20 cm long. These are followed by the flowers borne on a poker-shaped inflorescence called a spadix, which is partially enclosed in a pale green spathe or leaf-like hood. The spathe can be up to 25 cm high and the fruiting spike which follows later in the season may be up to 5 cm. The flowers are hidden from sight, clustered at the base of the spadix with a ring of female flowers at the bottom and a ring of male flowers above them. The leaves may be either purple-spotted (var. maculatum) or unspotted (var. immaculatum).
Above the male flowers is a ring of hairs forming an insect trap. Insects, especially owl-midges Psychoda phalaenoides, are attracted to the spadix by its faecal odour and a temperature up to 15 °C warmer than the ambient temperature. The insects are trapped beneath the ring of hairs and are dusted with pollen by the male flowers before escaping and carrying the pollen to the spadices of other plants, where they pollinate the female flowers. The spadix may also be yellow, but purple is the more common.
In autumn, the lower ring of (female) flowers forms a cluster of bright red, berries  up to 5 cms long which remain after the spathe and other leaves have withered away. These attractive red to orange berries are extremely poisonous.
The root-tuber may be very big and is used to store starch. In mature specimens, the tuber may be as much as 400 mm below ground level.
Many small rodents appear to find the spadix particularly attractive; finding examples of the plant with much of the spadix eaten away is common. The spadix produces heat and probably scent as the flowers mature, and this may attract the rodents.
Arum maculatum is also known as cuckoo pint or cuckoo-pint in the British Isles and is named thus in Nicholas Culpepers' famous 17th-century herbal. This is a name it shares with Arum italicum (Italian lords-and-ladies) - the other native British Arum. "Pint" is a shortening of the word "pintle", meaning penis, derived from the shape of the spadix. The euphemistic shortening has been traced to Turner in 1551.
The plant is propagated by birds dispersing the seeds by eating the berries. As a seedling the plant has small light green leaves that are not glossy like the mature leaves. At about 5 months its leaves grow larger and glossier. At one year old all of the leaves become glossy and die back. The next year the plant flowers during summer.


It grows in woodland areas and riversides. It can occasionally grow as a weed in partly shaded spots.


A. maculatum is the type species of the genus Arum.
Within the genus, it belongs to subgenus Arum, section Arum.
A. maculatum has a chromosome count of 2n = 56.


All parts of the plant can produce allergic reactions in many people and the plant should be handled with care.
The attractive berries are extremely poisonous to many animals, including humans, but harmless to birds, which eat them and propagate the seeds. They contain oxalates of saponins which have needle-shaped crystals that irritate the skin, mouth, tongue, and throat, and result in swelling of throat, difficulty breathing, burning pain, and upset stomach. However, their acrid taste, coupled with the almost immediate tingling sensation in the mouth when consumed, means that large amounts are rarely taken and serious harm is unusual. It is one of the most common causes of accidental plant poisoning based on attendance at hospital emergency departments.
There is no known antidote to A. maculatum poisoning. Airway management may reduce the mortality, and aggressive fluid administration may prevent renal injury.


The root of the cuckoo-pint, when roasted well, is edible and when ground was once traded under the name of Portland sago. It was used like salep (orchid flour) to make saloop, a drink popular before the introduction of tea or coffee.  It was also used as a substitute for arrowroot.  It can be highly toxic if not prepared correctly.
The leaves, which are toxic, can be mistaken for edible sorrel.
Arum maculatum is also used to make soup in the Andırın region of Turkey where the leaves are leavened with yogurt and boiled for long hours which eliminates toxicity. This process results in a sour soup which is called Tirşik.


Arum maculatum is cultivated as an ornamental plant in traditional and woodland shade gardens. The cluster of bright red berries standing alone without foliage can be a striking landscape accent. The mottled and variegated leaf patterns can add bright interest in darker habitats.
Arum maculatum may hybridize with Arum italicum.


The roots were a traditional source of starch for stiffening clothes. In 1440, the nuns of Syon Abbey in England used the roots of the cuckoo-pint flower to make starch for church linens; only starch "made of herbes" could be used for communion linen.


Arundinaria gigantea is a species of bamboo known as giant cane (not to be confused with Arundo donax) and river cane. It is endemic to the south-central and southeastern United States as far west as Oklahoma and Texas and as far north as New York. This species is divided into two subspecies. The subspecies tecta is sometimes treated as a species in its own right, Arundinaria tecta, and is the taxon generally called switch cane. It is very similar to the nominate subspecies (gigantea), but is often smaller and tends to grow in wetter habitats.
It and other species of Arundinaria may grow in large monotypic colonies called canebrakes. Canebrakes were once a common feature of the landscape in the southeastern United States, but today it is an endangered ecosystem.


This bamboo, which is a species of cane, is a perennial grass with a rounded, hollow stem which can exceed 7 cm (2.8 in) in diameter and grow to a height of 10 m (33 ft). It grows from a large network of thick rhizomes. The lance-shaped leaves are up to 30 cm (12 in) long and 4 cm (1.6 in) wide. The inflorescence is a raceme or panicle of spikelets measuring 4 to 7 cm (1.6 to 2.8 in) in length. An individual cane has a lifespan of about 10 years. Most reproduction is vegetative as the bamboo sprouts new stems from its rhizome. It rarely produces seeds and it flowers irregularly. Sometimes it flowers gregariously. Some types of non-native bamboos are confused with this native cane.


This native plant is a member of several plant communities today, generally occurring as a component of the understory or midstory. It grows in pine forests dominated by loblolly, slash, longleaf, and shortleaf pine, and stands of oaks, cypress, ash, and cottonwood. Other plants in the understory include inkberry (Ilex glabra), creeping blueberry (Vaccinium crassifolium), wax myrtle (Morella cerifera), blue huckleberry (Gaylussacia frondosa), pineland threeawn (Aristida stricta), cutover muhly (Muhlenbergia expansa), little bluestem (Schizachyrium scoparium), and toothache grass (Ctenium aromaticum). Cane communities occur on floodplains, bogs, riparian woods, pine barrens and savannas, and pocosins. It grows easily in flooded and saturated soils. It tolerates wildfire, and canebrakes are maintained by a normal fire regime.
This cane is the food plant for the southern pearly eye, a butterfly. Canebrakes are an important habitat for the Swainson's, hooded, and Kentucky warblers, as well as the white-eyed vireo. The disappearance of the canebrake ecosystem may have contributed to the rarity and possible extinction of the Bachman's warbler, which was dependent upon it for nesting sites.


Its leaves are kidney-shaped and persistent. Underground shoots are shallow-growing, fleshy rhizomes that branch to form a clump. Flowers bloom from April through June. Flowers are hairy and have three sepals. They are tan to purple in color on the outside and are lighter on the inside, with tapered tips and bases fused into a cup.
Pollinated flowers develop into a pod, which splits open when ripe to reveal seeds with elaiosomes, structures that are eaten by ants (myrmecochory).
The diploid chromosome number is 26.


The long rhizomes of A. canadense were used by Native Americans as a seasoning. It has similar aromatic properties to true ginger (Zingiber officinale), but should not be used as a substitute because it contains an unknown concentration of the carcinogen aristolochic acid and asarone. The distillate from the ground root is known as Canadian snakeroot oil. The odor and flavor are spicy. It has been used in many flavor preparations.
Native Americans used the plant as a medicinal herb to treat a number of ailments including dysentery, digestive problems, swollen breasts, coughs and colds, typhus, scarlet fever, nerves, sore throats, cramps, heaves, earaches, headaches, convulsions, asthma, tuberculosis, urinary disorders, and venereal disease. In addition, they also used it as a stimulant or appetite enhancer, and as a charm. It was also used as an admixture to strengthen other herbal preparations.


The erebid moth Ascalapha odorata, commonly known as the black witch, is a large bat-shaped, dark-colored nocturnal moth, normally ranging from the southern United States to Brazil. Ascalapha odorata is also migratory into Canada and most states of United States. It is the largest noctuoid in the continental United States. In the folklore of many Central American cultures, it is associated with death or misfortune.


Female moths can attain a wingspan of 24 cm. The dorsal surfaces of their wings are mottled brown with hints of iridescent purple and pink, and, in females, crossed by a white bar. The diagnostic marking is a small spot on each forewing shaped like a number nine or a comma. This spot is often green with orange highlights. Males are somewhat smaller, reaching 12 cm in width, darker in color and lacking the white bar crossing the wings. The larva is a large caterpillar up to 7 cm in length with intricate patterns of black and greenish-brown spots and stripes.


The black witch lives from the southern United States, Mexico and Central America to Brazil, and has apparently been introduced to Hawaii.
Adults feed on overripe rainforest fruit, especially bananas, and larvae consume the leaves of plants. Most of its host plants are legumes. It favors Acacia species, Kentucky coffeetree (Gymnocladus dioicus), and candle bush (Senna alata). It attacks mesquite and ficus, and can be an agricultural pest.
The black witch flies north during late spring and summer. One was caught during an owl banding project at the Whitefish Point lighthouse on the shoreline of Lake Superior in July 2020.


The black witch is considered a harbinger of death in Mexican and Caribbean folklore. In many cultures, one of these moths flying into the house is considered bad luck: e.g., in Mexico, when there is sickness in a house and this moth enters, it is believed the sick person will die, though a variation on this theme (in the lower Rio Grande Valley, Texas) is that death only occurs if the moth flies in and visits all four corners of one's house (in Mesoamerica, from the pre-Hispanic era until the present time, moths have been associated with death and the number four). In some parts of Mexico, people joke that if one flies over someone's head, the person will lose his hair.
In Jamaica, under the name duppy bat, the black witch is seen as the embodiment of a lost soul or a soul not at rest. In Jamaican English, the word duppy is associated with malevolent spirits returning to inflict harm upon the living and bat refers to anything other than a bird that flies. The word "duppy" (also: "duppie") is also used in other West Indian countries, generally meaning "ghost".
In Brazil it is called "mariposa-bruxa", "mariposa-negra", "bruxa-negra", and "bruxa, and it is also believed that when a moth of this type enters the house it can bring some “bad omen”, signaling the death of a resident. In the Ecuadorian highlands they are called Tandacuchi and in Peru Taparacuy or Taparaco. These countries share the belief that if this moth, a messenger of death, appears in your home, someone will die very soon.
In Hawaii, black witch mythology, though associated with death, has a happier note in that if a loved one has just died, the moth is an embodiment of the person's soul returning to say goodbye. In the Bahamas, where they are locally known as money moths or money bats, the legend is that if they land on you, you will come into money, and similarly, in South Texas, if a black witch lands above your door and stays there for a while, you will supposedly win the lottery.
In Paraguay and Argentina, this insect is mostly known as "ura", and there is a popular belief that this moth urinates and leaves worms on the skin of people and animals. However, the insect that lays eggs in the skin and whose larvae become embedded in the flesh is the colmoyote or screwworm (Dermatobia hominis).
In Spanish, the black witch is known as "mariposa de la muerte" (Mexico and Costa Rica), "pirpinto de la yeta" (Argentina), "tara bruja" (Venezuela) or simply "mariposa negra" (Colombia); in Nahuatl (Mexico) it is "Miquipapalotl" or "Tepanpapalotl" (miqui = death, black + papalotl = moth); in Quechua (Peru) it is "Taparaco"; in Mayan (Yucatán) it is "X-mahan-nah" (mahan = to borrow + nah = house). Other names for the moth include the papillion-devil, la sorcière noire, the mourning moth or the sorrow moth.


Black witch moth pupae were placed in the mouths of victims of serial killer 'Buffalo Bill' in the novel The Silence of the Lambs. In the movie adaptation, they were replaced by death's-head hawkmoth pupae.


Thysania agrippina – white witch
Thysania zenobia – owl moth


Asclepias albicans is a species of milkweed known by the common names whitestem milkweed and wax milkweed. It is native to the Mojave and Sonoran Deserts of California, Arizona, and Baja California. This is a spindly erect shrub usually growing 1 to 3 meters (3+1⁄2 to 10 feet) tall, but known to approach 4 meters. The sticklike branches are mostly naked, the younger ones coated in a waxy residue and a thin layer of woolly hairs. The leaves are ephemeral, growing in whorls of three on the lower branches and falling off after a short time. They are linear in shape and up to 3 centimeters (1+1⁄4 inches) long. The inflorescence is an umbel about 5 cm (2 in) wide which appears at the tips of the long branches and sprouting from the sides at nodes. The inflorescence contains many purple-tinted greenish flowers, each about 1.5 cm (1⁄2 in) wide, with a central array of bulbous hoods, and corollas reflexed back against the stalk. The plant usually blooms from March to May. The fruit is a large, long, thick follicle which dangles in bunches from the branch nodes.
The similar A. subulata is found in similar regions.


Asclepias amplexicaulis, the blunt-leaved milkweed, clasping milkweed, or sand milkweed, is a species of flowering plant in the subfamily Asclepiadoideae (Apocynaceae). It is endemic to the United States, where it is mostly found east of the Great Plains. It grows in dry prairies, savannas, open woods, and fallow fields, usually in sandy soil.


It grows 1–3 ft (0.30–0.91 m) high and produces flowers in the summer.
This plant was eaten as food historically. However, it contains a poison dangerous to humans and livestock, so caution must be used if ingesting this plant.


Asclepias asperula, commonly called antelope horns milkweed or spider milkweed, is a species of milkweed native to the Southwestern United States and northern Mexico.


It is a perennial plant growing to 0.3–0.9 m (1–3 ft) tall, with clustered greenish-yellow flowers with maroon highlights.  It blooms from April through June.
Antelope horns is a common milkweed in Central Texas.  It gets its name from the follicles (seed pods) that resemble the horns of antelope.  You can easily spot the flower clusters (technically, umbellate cymes) in open meadows.  Milkweed plants are a major food source for Monarch and Queen butterfly caterpillars and as with other milkweed plants, it bleeds white latex if a stem is cut and this sap is toxic to some animals and to humans.  It also makes Monarch and Queen butterflies taste bad to potential predators, a nice defense mechanism. From a distance the flowers appear as tennis-sized spheres, but they are clusters of small green, purple, and white flowers.  Each flower has 5 pale green petals that cup upward around 5 prominent white hoods (which store nectar).


The central circular structure is a gynostegium, the fusion of 2 stigma and 5 anthers.  Antelope horns do not have individual pollen grains.  The pollen sticks together as granular masses contained on a pollinarium structure located within each of the 5 stigmatic chambers.  The pollinarium is made up of 2 pollinium “wings” connected to a central corpusculum via 2 translator arms.  The picture "Antelope horns pollinarium" shows a pollinarium that was pulled out of the stigmatic slit using an insect pin.


Pollination of Antelope Horns happens when flowers are visited by insects that get their reward in nectar (in this case primarily sucrose) which is accessible at the base of each of the hoods.  Several different types of insects visit milkweed searching for nectar including bees, butterflies, moths, flies and beetles.   As they move around the flower in search of nectar one of their legs may slip into a stigmatic slit.  The only way to safely remove their leg is to move it upwards toward the top of the slit.  The leg can then snag on the corpusculum and pull out the entire pollinarium.  When the insect visits another milkweed flower carrying this pollinarium, there is a chance a pollinium would slip into an empty stigmatic slit, dislodge, and remain there.  If the orientation of the pollinium is correct and the concentration of nectar surrounding a pollinium is optimal, pollination will take place.
Pollen tubes grow out of a germination pore on the convex surface of the pollen mass on pollinium into the stigma and down one of the 2 styles to the ovary where the male genetic material fertilizes the (female) ovules.  Each ovule has the potential to form one seed.   The image "Antelope Horns pollen tube" shows the route pollen tubes take to transfer genetic material into an ovary.  Asclepias asperula does not self-pollinate so they are dependent on attracting pollinators that will transfer pollen between plants.


Asclepias asperula is divided into two subspecies: A. asperula. ssp. asperula and A. asperula ssp. capricornu.  Ssp. capricornu occurs in comparatively more mesic conditions and has comparatively broader leaves, floral crowns that are more white, and a more prostrate habit.  Ssp. asperula occurs in comparatively more arid conditions and has comparatively narrower leaves, floral crowns that are more purple, and a more upright habit.


Like several other species of milkweed, A. asperula is a food for monarch butterfly caterpillars. Along with being food for monarchs, the plants also contain toxic cardiac glycosides (cardenolides) that the monarchs retain, making them unpalatable and poisonous to predators.  For the same reason, A. asperula can be poisonous to livestock and other animals, including humans.
In addition to the monarch, it is a larval host to the dogbane tiger moth, the queen butterfly, and the unexpected cycnia.


The plant is difficult to cultivate and does not grow well in containers. In cultivation, this species favors quickly draining soil that is high in inorganic matter, such as sand and rock chips. It can grow in loam and clay, if provided with adequate drainage and frequent dryness. Moisture level demands and tolerance depend upon the subspecies and possibly ecotype. The plant has a deep taproot, so it needs to have the deepest-possible pot if grown in a container and should not be waterlogged.


Asclepias cordifolia is a species of milkweed commonly called  heart-leaf milkweed or purple milkweed (a common name shared with another milkweed, Asclepias purpurascens). It is native to the western United States (California, Nevada, Oregon), growing between 50 to 2,000 m (160 to 6,560 ft) elevation in the northern Sierra Nevada and Cascade ranges. Heart-leaf milkweed was valued by the Native American Miwok tribe for its stems, which they dried and processed into string and rope.


Heart-leaf milkweed is a perennial that grows to a height of 0.3 to 0.6 m (1 to 2 ft), with dark red-purple flowers whose hoods are slightly elevated above the base of the corolla. The flower structure is unusual—it has five stamens fused into a column, with five circular attachments called 'hoods', and an anther head surrounding the large stigma at the flower's center. The fruit (photo at left) is a follicle with many flat seeds that have silky hairs which disperse easily in the wind. The large opposite leaves are cordate, or heart-shaped. The plant grows in open or shaded woodland, often on rocky slopes and in mixed coniferous forest. The milkweeds are named for the milky sap which exudes from the plant's stem.
It blooms from May to July.


The Miwok gathered heart-leaf milkweed in the summer and dried it, or collected it in the fall [autumn, most likely between September and December) after it was already dry. The dry stems were combed with a loop of willow to draw out the fiber just beneath the very thin outer skin. The fiber was wound into balls for storage and later processing. The making of cordage (rope and string) was done entirely by hand, with no tools. Asclepias was also used by the Native American Yokut or Mariposa in northern and central California for string or rope.
A single Miwok feather skirt or cape was made with approximately 100 feet of cordage, requiring about 500 plant stalks. A 40-foot-long deer net contained about 7,000 feet of cordage, requiring the harvesting of approximately 35,000 plant stalks. The milkweed stalks were burned in the fall to eliminate dead stalks and stimulate the next year's growth, and to stimulate flower and seed production. Cordage was typically two-ply, though there are some examples at the Field Museum of three- and four-ply Miwok cordage.
Heart-leaf milkweed was also used as a contraceptive and snakebite remedy, though without proper preparation it can cause vomiting in low doses and death in higher doses due to a mix of cardenolides in the sap. At one time it was classified as a noxious weed because of reported negative effects on livestock.


Asclepias curassavica, commonly known as tropical milkweed, is a flowering plant species of the milkweed genus, Asclepias. It is native to the American tropics and has a pantropical distribution as an introduced species. Other common names include bloodflower or blood flower, cotton bush, hierba de la cucaracha, Mexican butterfly weed, redhead, scarlet milkweed, and wild ipecacuanha.
It is grown as an ornamental garden plant and as a food source for some butterflies, however it may be harmful to the migration patterns of monarch butterflies when used in gardens outside of its native tropical range. Though public concern for the rapidly declining monarch population increased the demand and commercial availability of milkweed among nurseries in the US, the results have been mixed. While tropical milkweed may effectively sustain monarch larvae, the perennial growth of the plant takes ill effect on the monarchs' migratory patterns and may have other physiological effects. Use of the tropical milkweed in gardens has disrupted monarch migrations notably in California, Texas, Florida, and South Carolina. Unlike the milkweed species native to these locations, the tropical milkweed does not go dormant in the winter causing non-migratory groups of butterflies to form. Planting Asclepias curassavica in nonnative regions therefore remains controversial and criticized. Alternatively, native milkweed species (such as showy milkweed, narrowleaf milkweed, and desert milkweed for California) are suggested for butterfly gardens.
It also attracts members of the Danainae subfamily, such as the queen.


Typical plants are evergreen perennial subshrubs that grow up to 1 m (3.3 ft) tall and have pale gray stems. The leaves are arranged oppositely on the stems and are lanceolate or oblong-lanceolate shaped ending in acuminate or acute tips. Like other members of the genus, the sap is milky. The flowers are in cymes with 10-20 flowers each. They have purple or red corollas and corona lobes that are yellow or orange. Flowering occurs nearly year-round. The 5–10 cm (2.0–3.9 in) long, fusiform shaped fruits are called follicles. The follicles contain tan to brown seeds that are ovate in shape and 6–7 mm (0.24–0.28 in) long. The flat seeds have silky hairs that allow the seeds to float on air currents when the pod-like follicles dehisce (split open).


Asclepias curassavica is described by NatureServe as a "widespread species, ranging from southern North America through Central America and into South America."
It is an introduced species in the US states of California, Florida, Hawaii, Louisiana, Tennessee, and Texas, as well as the US unincorporated territories of Puerto Rico and the United States Virgin Islands.
It has been introduced and naturalized in the Chinese provinces of Anhui, Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hubei, Hunan, Jiangsu, Jiangxi, Qinghai, Sichuan, Xizang, Yunnan, and Zhejiang, as well as in Taiwan.
Asclepias curassavica was introduced to Australia prior to 1869 and is widespread in parts of Queensland. It is considered an exotic plant, and a weed, at the Meteor Downs South Project near Rolleston, Queensland, Australia.


Asclepias curassavica contains several cardiac glycosides, including asclepin, calotropin, uzarin and their free genins, calactin, coroglucigenin and uzarigenin. It also contains oleanolic acid, β-sitosterol, and glycosides of asclepin. The most abundant cardiac glycoside present in Asclepias curassavica leaves is voruscharin, which comprises around 40% of the total cardiac glycoside content in leaves.


Asclepias eriocarpa is a species of milkweed known by the common names woollypod milkweed, Indian milkweed, and kotolo. It is a perennial herb that grows in many types of habitats.


Asclepias eriocarpa is native to California and adjacent parts of Nevada and Baja California. It grows in many habitat types such as rocky hillsides, woods, deserts, and especially dry areas.


Asclepias eriocarpa is a specific monarch butterfly food and habitat plant.
It is one of the most poisonous milkweeds. Natural History July/August 2015 calls it the most poisonous, but most sources put it below A. lancifolia (now known as Asclepias perennis).


Asclepias exaltata (poke milkweed or tall milkweed) is a species of flowering plant in the dogbane family, native to eastern North America.
It blooms from late spring to early summer. The flowers are green and white.
Poke milkweed is found in moist woodland habitats, shores, and woodland edges. It grows in moist soil and sunny or partly shaded places. It grows from 0.6 to 1.5 meters (2.0 to 4.9 ft) tall.


Asclepias hirtella, commonly called the tall green milkweed, is a species of flowering plant in the milkweed genus and dogbane family (Apocynaceae). It is native to Canada and the United States, where its range is concentrated in the Midwest and Upper South.


Asclepias hirtella is a tall perennial, reaching 3 feet in height. It has many narrow, linear leaves that are produced alternately on the stem. Its flowers in lateral umbels with slender peduncles.  Each stem may have 2 to 10 umbels and each umbel may have 30 to 100 flowers. The flowers lack horns and are greenish to slightly purplish in color. It flowers June thru Aug.
This species closely resembles Asclepias longifolia, and it is occasionally treated to be a subspecies of it. Asclepias longifolia is restricted to the Southeastern Coastal Plain, and it differs from Asclepias hirtella in its fewer and smaller flower umbels, and its glabrous leaves.


Asclepias hirtella is found in a variety of open habitats, including areas with dry sandy soil, prairies and limestone glades, It can be found in both wet and dry conditions, and it prefers open habitats with full sun. This species is a component of high-quality grassland communities, although it can be found in and disturbed conditions as well. It is considered to be uncommon throughout much of its range.


Asclepias hirtella is native to West Virginia, Ohio, Michigan and Wisconsin to northerner Iowa, Kansas, Oklahoma to south western Kentucky. It is a prairie species native to 13 US states and one Canadian province, but is becoming rare or declining in numbers in parts of its native range. A. hirtella  is rare in Minnesota and listed as a threatened species in that state, where it occurs in the south eastern corner in mesic prairie habitats.


Asclepias humistrata, the sandhill milkweed, is a species of milkweed plant. It is also known as pinewoods milkweed and pink-veined milkplant. It belongs in the subfamily Asclepiadoideae. It is native to the southeastern United States. It blooms in spring and summer. The flowers are pink lavender and white. It is found in well-drained areas such as sandy woodlands, sandy hills, and Florida scrub. Sandhill milkweed likes dry soil and sunny places. It grows from 0.3 to 0.9 meters (0.98 to 2.95 ft) tall.


Asclepias linaria is a species of milkweed known by the common name pineneedle milkweed.
It is native to the Mojave and Sonoran Deserts of Northwestern Mexico and the U.S. states of California and Arizona.
This is a large erect perennial herb or shrub coated in hairs and many narrow, green leaves which resemble pine needles. The inflorescence is an umbel-like cluster of flowers, each with pink-tinted rounded hoods at the center and greenish reflexed corollas. The fruit is a follicle.
Research indicates that the very high cardenolide content of this species reduces the impact of the OE parasite, Ophryocystis elektroscirrha, on the monarch butterfly, Danaus plexippus. By contrast, some species of Asclepias are extremely poor sources of cardenolides.


Asclepias purpurascens, the purple milkweed, is a herbaceous plant species.  It is in the genus Asclepias, making it a type of milkweed.  It is native to the Eastern, Southern and Midwestern United States similar to the range of the common milkweed (Asclepias syriaca).  The plant gets its name from the flowers that first develop a pink color but then turn darker purple as they mature. Unlike common milkweed, purple milkweed prefers some shade and is considered a plant of partial shade. It is also considered an indicator of oak savanna, especially in Wisconsin. The species rarely produces seed pods which are smooth instead of the rough warty ones produced by common milkweed.


It is listed endangered in Massachusetts and Wisconsin, as historical to Rhode Island, as imperiled in Maryland and as a special concern species in Connecticut and Tennessee.


Like other members of the milkweeds, several insects live off the plant, including the monarch butterfly (Danaus plexippus), the milkweed beetle (Tetraopes tetraophtalmus), large milkweed bug (Oncopeltus fasciatus), small milkweed bug (Lygaeus kalmii) and milkweed leaf beetle (Labidomera clivicollis).  Other insects and pollinators feed off the flower's nectar.
This species is sometimes cultivated in gardens designed to attract butterflies, but is less common than the light purple swamp milkweed (Asclepias incarnata) or the orange butterfly weed (Asclepias tuberosa). The nectar of the plant attracts many other species of butterflies and insects.


Asclepias subverticillata is a plant found in the southwestern United States and Mexico. Common names include horsetail milkweed, poison milkweed and whorled milkweed.


Growing to 1.2 metres (4 feet) in height, short branches support leaves ranging from 2–12.5 centimeters (1–5 inches) in length. Blooming from May to September, the umbel is 2–3 cm (3⁄4–1+1⁄4 in) wide, with individual flowers up to 1.5 cm (1⁄2 in) across; each has five petals and five sepals. The fruit pod is smooth and 5–10 cm (2–4 in) long; the seeds inside have long hairs.


It is indigenous to New Mexico, Arizona, Colorado and Utah and parts of some nearby states, in addition to Mexico.


The species is unpalatable and very toxic to livestock.


Among the Zuni people the buds are eaten by young boys. The pods are also gathered when two-thirds ripe and the fibers are used for weaving clothing. The coma is made into cords and used for fastening plumes to the prayer sticks.


Asclepias tuberosa, the butterfly weed, is a species of milkweed native to eastern and southwestern North America. It is commonly known as butterfly weed because of the butterflies that are attracted to the plant by its color and its copious production of nectar.


It is a perennial plant growing to 0.3–1 m (1–3+1⁄2 ft) tall. The leaves are spirally arranged, lanceolate, 3–12 cm (1+1⁄4–4+3⁄4 in) long, and 2–3 cm (3⁄4–1+1⁄4 in) broad.
From April to September, in the upper axils, 7.5 cm (3 in)–wide umbels of orange, yellow or red flowers 1.5 cm (1⁄2 in) wide appear. They each have five petals and five sepals. It is uncertain if reddish flowers are due to soil mineral content, ecotype genetic differentiation, or both. A cultivar named 'Hello Yellow' typically has more yellowish flowers than ordinary examples of this plant.
The fruit pod is 7.5–15 cm (3–6 in) long, containing many long-haired seeds.


The plant looks similar to the lanceolate milkweed (Asclepias lanceolata), but is uniquely identified by the larger number of flowers, and the hairy stems that are not milky when broken. It is most commonly found in fields with dry soil.


Asclepias tuberosa subsp. interior – (Central United States, Ontario and Quebec)
Asclepias tuberosa subsp. rolfsii – Rolfs milkweed (Southeastern United States)
Asclepias tuberosa subsp. tuberosa – (Eastern United States)


Common names include butterfly weed, Canada root, chieger flower, chiggerflower, fluxroot, Indian paintbrush, Indian posy, orange milkweed, orange root, orange Swallow-wort, pleurisy root, silky swallow-wort, tuber root, yellow milkweed, white-root, windroot, butterfly love, butterflyweed, and butterfly milkweed.


The species can be found from South Dakota south to Texas and Mexico, west to Utah and Arizona, as well as some other areas further east.
This plant favors dry, sand or gravel soil, but has also been reported on stream margins. It requires full sun.


Most easily propagated by seed. The primary pollinators are bees and wasps, rather than butterflies. Sown outdoors after frost, a plant will flower and produce seed in the third year.  It is difficult to transplant once established, as it has a deep, woody taproot.
A. tuberosa is a larval food plant of the queen and monarch butterflies, as well as the dogbane tiger moth, milkweed tussock moth, and the unexpected cycnia. Because of its rough leaves, it is not a preferred host plant of the monarch butterfly but caterpillars can be reared on it successfully. Further, it is one of the very lowest Asclepias species in cardenolide content, making it a poor source of protection from bird predation and parasite virulence and perhaps contributing to its lack of attractiveness to egg-laying monarchs.


To protect seeds from washing away during heavy rains and from seed–eating birds, one can cover the seeds with a light fabric or with an 0.5 in (13 mm) layer of straw mulch. However, mulch acts as an insulator. Thicker layers of mulch can prevent seeds from germinating if they prevent soil temperatures from rising enough when winter ends. Further, few seedlings can push through a thick layer of mulch.
In cultivation in the greenhouse, plants can easily be grown from seed to flowering in as little as three to six months. The seeds often need periods of cold treatment (cold stratification) before they will germinate.


The plant contains toxic glycosides, alkaloids and resinoids. These can cause weakness, seizures and corneal injuries. Use of the plant is contraindicated in pregnancy, during lactation or with infants due to its toxins, which include resinoids and pregnanes.
Because monarch butterflies do not favor it when reproducing, it is not as suitable for use in butterfly gardens and monarch waysides as are other milkweed species.


Native Americans and European pioneers used the boiled roots to treat diarrhea and respiratory illnesses. The young seed pods were used as food after being boiled in several changes of water. The seed pod down was spun and used to make candle wicks.
The root was once used to treat pleurisy.


Asclepias verticillata, the whorled milkweed, eastern whorled milkweed, or horsetail milkweed, is a species of milkweed native to most of eastern North America and parts of western Canada and the United States.


This is a perennial herb with a single stem 6 inches to 3 feet tall. The very narrow, linear leaves are arranged in whorls of 4–6 with short internodes. The inflorescence is an umbel of 7–20 greenish white flowers. Flowers are fragrant and bloom between June and September. Its native habitats include glades, dry prairies, dry slopes, dry open woods, pastures, fields, and roadsides. The Latin specific epithet verticillata is in reference to the leaves appearing in whorls.


This species can reproduce vegetatively and does not depend on pollinators, but it does produce some nectar, mostly in the early evening hours. Insect visitors to the plant include wasps, honeybees, and lepidopterans such as moths and the cabbage white. Like other milkweed species, this plant is a host plant for the monarch butterfly whose caterpillars feed on the leaves.
The plant is toxic to livestock.


It was used as a medicinal plant by Native American peoples. The Choctaw used it to treat snakebite, the Lakota and Hopi used it to increase breast milk in nursing mothers, and the Navajo used it for nose and throat problems.


Asclepias viridiflora, is commonly known as green comet milkweed,  green-flower milkweed, and green  milkweed. It is a widely distributed species of milkweed (Asclepias), known from much of the eastern and central United States from Connecticut to Georgia to Arizona to Montana, as well as southern Canada. The Latin specific epithet viridiflora means green-flowered.
Asclepias viridiflora  is an erect to ascending herb up to 50 cm tall, with distinctive greenish-white flowers. The pods lack the warts and tubercules common on other species of Asclepias. It grows in moist to dry shaded roadsides, fields, and prairies.


It is listed as endangered in Florida, as threatened in New York (state), and as endangered in Connecticut.


Asclepias viridis is a species of milkweed, a plant in the dogbane family known by the common names green milkweed, green antelopehorn and spider milkweed. The Latin word  viridis means green. The plant is native to the midwestern, south central and southeastern United States, as well as to the southeastern portion of the western United States.
A. viridis is a perennial forb with alternately arranged leaves. The inflorescence is an umbel of white flowers with purplish centers. Its root system is a taproot, like that of butterfly weed (A. tuberosa).
A. viridis grows on many types of soil. It is common in overgrazed pasture land and roadsides.


The plant is difficult to cultivate and does not grow well in containers. The seeds of some milkweeds need periods of cold treatment (cold stratification) before they will germinate. To protect seeds from washing away during heavy rains and from seed–eating birds, one can cover the seeds with a light fabric or with an 0.5 in (13 mm) layer of straw mulch.  However, mulch acts as an insulator. Thicker layers of mulch can prevent seeds from germinating if they prevent soil temperatures from rising enough when winter ends. Further, few seedlings can push through a thick layer of mulch.


This plant's scientific name is Asimina triloba. The genus name Asimina is adapted from the Native American (probably Miami-Illinois) name assimin or rassimin through the French colonial asiminier. The specific epithet triloba in the species' scientific name refers to the flowers' three-lobed calyces and doubly three-lobed corollas, the shape not unlike a tricorne hat.
The common name of this species is variously spelled pawpaw, paw paw, paw-paw, and papaw. It probably derives from the Spanish papaya, an American tropical and subtropical fruit (Carica papaya) sometimes also called "papaw", perhaps because of the superficial similarity of their fruits and the fact that both have very large leaves. The name pawpaw or papaw, first recorded in print in English in 1598, originally meant the giant herb Carica papaya or its fruit (as it still commonly does in many English-speaking communities, including Australia, New Zealand, and South Africa). Daniel F. Austin's Florida Ethnobotany states that:
The original "papaw" ... is Carica papaya. By 1598, English-speaking people in the Caribbean were calling these plants "pawpaws" or "papaws" ... [yet later, when English-speakers settled in] the temperate Americas, they found another tree with a similarly aromatic, sweet fruit. It reminded them of the "papaya", which had already become "papaw", so that is what they called these different plants ...  By 1760, the names "papaw" and "pawpaw" were being applied to A. triloba.
Yet A. triloba has had numerous local common names, many of which compare it to a banana rather than to Carica papaya. These include: wild banana, prairie banana, Indiana banana, Hoosier banana, West Virginia banana, Kansas banana, Kentucky banana, Michigan banana, Missouri banana, Appalachian banana, Ozark banana, Indian banana, banango, and the poor man's banana, as well as American custard apple, asimoya, Quaker delight, and hillbilly mango.
Due to increased interest in the foraging and locavore food movement during the late 2010s and the COVID-19 pandemic, the pawpaw has been referred to tongue-in-cheek as the "hipster banana".
Several tribes of Native Americans have terms for the pawpaw such as riwahárikstikuc (Pawnee), tózhaⁿ hu (Kansa), and umbi (Choctaw).


A. triloba is a large shrub or small tree growing to a height of 35 ft (11 m), rarely as tall as 45 ft (14 m), with trunks 8–12 in (20–30 cm) or more in diameter. The large leaves of pawpaw trees are clustered symmetrically at the ends of the branches, giving a distinctive imbricated appearance to the tree's foliage.
The leaves of the species are simple, alternate and spirally arranged, entire, deciduous, obovate-lanceolate, 10–12 in (25–30 cm) long, 4–5 in (10–13 cm) broad, and wedge-shaped at the base, with an acute apex and an entire margin, with the midrib and primary veins prominent. The petioles are short and stout, with a prominent adaxial groove. Stipules are lacking. The expanding leaves are conduplicate, green, covered with rusty tomentum beneath, and hairy above; when fully grown they are smooth, dark green above, and paler beneath. When bruised, the leaves have a disagreeable odor similar to a green bell pepper. In autumn, the leaves are a rusty yellow, allowing pawpaw groves to be spotted from a long distance.
Pawpaw flowers are perfect, about 1–2 in (3–5 cm) across, rich red-purple or maroon when mature, with three sepals and six petals. They are borne singly on stout, hairy, axillary peduncles. The flowers are produced in early spring at the same time as or slightly before the new leaves appear, and have a faint fetid or yeasty smell.
The fruit of the pawpaw is a large, yellowish-green to brown berry, 2–6 in (5–15 cm) long and 1–3 in (3–8 cm) broad, weighing from 0.7–18 oz (20–510 g), containing several brown or black seeds 1⁄2–1 in (15–25 mm) in diameter embedded in the soft, edible fruit pulp. The conspicuous fruits begin developing after the plants flower; they are initially green, maturing by September or October to yellow or brown. When mature, the heavy fruits bend the weak branches down.
Other characteristics:
Calyx: Sepals three, valvate in bud, ovate, acuminate, pale green, downy
Corolla: Petals six, in two rows, imbricate in the bud; inner row acute, erect, nectariferous; outer row broadly ovate, reflexed at maturity; petals at first are green, then brown, and finally become dull purple or maroon and conspicuously veiny
Stamens: Indefinite, densely packed on the globular receptacle; filaments short; anthers extrorse, two-celled, opening longitudinally
Pollen: Shed as permanent tetrads
Pistils: Several, on the summit of the receptacle, projecting from the mass of stamens; ovary one-celled; stigma sessile; ovules many
Branchlets: Light brown, tinged with red, marked by shallow grooves
Winter buds: Small, of two kinds, the leaf buds pointed and closely appressed to the twigs, and the flower buds round, brown, and fuzzy
Bark: Light gray, sometimes blotched with lighter gray spots, sometimes covered with small excrescences, divided by shallow fissures; inner bark tough, fibrous; bark with a very disagreeable odor when bruised
Wood: Pale, greenish yellow, sapwood lighter; light, soft, coarse-grained and spongy with a specific gravity of  0.3969 and a density of 24.74 pounds per cubic foot (396.3 kg/m³)
Longevity of fruit production: Undetermined


The floral scent of Asimina triloba has been described as "yeasty," which is one of several features that signify a "beetle pollination syndrome." Other floral features of pawpaw indicative of beetle pollination include petals that curve over the downward-pointing flower center, along with food-rich fleshy bases of the inner whorl of petals. A "pollination chamber" is thereby created at a depth that only small beetles can access during the initial female-receptive stage of floral bloom. As with other well-studied species of Annonaceae, the delay in the shift from female to male floral stage offers beetles a secure, and possibly thermogenic, residence in which not only to feed but also to mate. Receptive stigmas at their arrival, followed by pollen-shedding stamens during pollinator departure is regarded as an early form of mutualism (biology) evolved between plants and insects that is still dominant in the most ancient lineages of flowering plants, including the Magnoliids (of which Annonaceae is the most species-rich taxonomic family).
Beetles are the dominant form of pollinator ascribed for genera and species within Family Annonaceae. However, two species of genus Asimina (Asimina triloba and Asimina parviflora) bear a floral character that has given rise to an alternative hypothesis that carrion or dung flies are their effective pollinators. That floral characteristic is the dark maroon color of the petals. Hence, while no scholarly papers have documented carrion or dung flies as effective pollinators in field observations, the strength of this hypothesis has led to placement of carrion during the bloom time in pawpaw orchards by some horticultural growers.
Professional papers on genus Asimina and its species have warned of the difficulties in discerning whether insects observed on or collected from flowers are effective pollinators or merely casual and thus opportunistic visitors.


On a global (range-wide) scale, the common pawpaw (A. triloba) has a NatureServe global conservation rank of G5 (very common), but faces problems in the northernmost parts of its range; in the United States, the species has an N5 (very common), but is considered a threatened species in New York, and an endangered species in New Jersey. In Canada, where the species is found only in portions of southern Ontario, it has a  rank of N3 (vulnerable), and a NatureServe subnational conservation rank of S3 (vulnerable) in Ontario. The Ontario Ministry of Natural Resources has given the species a general status of "Sensitive", and its populations there are monitored.
In areas in which deer populations are dense, pawpaws appear to be becoming more abundant locally, since the deer avoid them, but consume seedlings of most other woody plants.


The natural seed dispersal of the common pawpaw in North America, prior to the ice ages and lasting until roughly 10,000 years ago, occurred via the dung of certain megafauna (such as mastodons, mammoths, and giant ground sloths) until they became extinct during the Quaternary extinction event — a parallel case in North America to that of the avocado in South and Central America. After the arrival of humans and the subsequent extinction of megafauna that were distributing A. triloba, the probable distribution of these large fruit-bearing plants has been by humans.
Indigenous peoples value pawpaw not only for its fruit but also for its bark. The bark has traditionally been used as a fiber source. Now that the exotic emerald ash borer beetle is destroying black ash trees (Fraxinus nigra), a basketmaker of the Little Traverse Bay Bands of Odawa Indians in northern Michigan has begun planting pawpaw seeds on tribal lands several hundred miles north of pawpaw's historically native range.
The earliest documented mention of pawpaws is in the 1541 report of the Spanish de Soto expedition, who found Native Americans east of the Mississippi River cultivating what some have identified as the pawpaw. The tree’s scientific name (Asimina triloba) comes from the Powhatan word Assimina, which a Jamestown settler transcribed in 1612 as “wheat plum". The Lewis and Clark Expedition consumed pawpaws during their travels. Thomas Jefferson planted it at Monticello, his home in Virginia. Legend has it that chilled pawpaw fruit was a favorite dessert of George Washington.


Cultivation is best in hardiness zones 5-9 and trees take 7-8 years from seedling to fruiting. Cross-pollination of at least two different genetic varieties of the plant is recommended. Scholarly research is insufficient for horticulturalists to adopt best methods for attracting insect pollinators, as effective pollinators have not yet been distinguished from casual insect visitors. Therefore, some growers resort to hand pollination or use pollinator attractants, such as spraying fish emulsion or hanging chicken necks or other meat near the open flowers to attract pollinators.
While pawpaws are larval hosts for the zebra swallowtail butterfly, these caterpillars are usually present only at low density, and not detrimental to the foliage of the trees.
Pawpaws have not been cultivated for their fruits on the scale of apples or peaches, primarily because pawpaw fruits ripen to the point of fermentation soon after they are picked, and only frozen fruit stores or ships well. Other methods of preservation include dehydration, production of jams or jellies, and pressure canning (using the numerical values for bananas). Methods of separating seeds from the pulp are still in the experimental phase. Mechanical methods are most efficient, but any splitting or injury of seeds can contaminate the remaining pulp with seed poisons.
Cultivation of pawpaws for fruit production has attracted interest, particularly among organic growers, as a fruit with few to no pests that can successfully be grown in its native environment without pesticides. The commercial cultivation and harvesting of pawpaws is strong in southeastern Ohio and also being explored in Kentucky and Maryland, as well as various areas outside the species' native range, including California, the Pacific Northwest, and Massachusetts.
The pawpaw is used for landscaping due to its distinctive growth habit, the appeal of its fresh fruit, and its relatively low maintenance needs once established.


Phytochemical extracts of the leaves and fruit contain acetogenins, including the neurotoxin annonacin. The seeds and bark contain the chemical asimitrin and other acetogenins, including asimin, asiminacin and asiminecin.


The short-eared owl (Asio flammeus) is a widespread grassland species in the family Strigidae. Owls belonging to genus Asio are known as the eared owls, as they have tufts of feathers resembling mammalian ears. These "ear" tufts may or may not be visible. The short-eared owl will display its tufts when in a defensive pose, although its very short tufts are usually not visible. The short-eared owl is found in open country and grasslands.


The short-eared owl was formally described in 1763 by the Lutheran bishop Erik Pontoppidan under the binomial name Strix flammea. The specific epithet is from the Latin flammeus meaning "flammulated" or "flame-coloured". This owl is now placed with seven other species in the genus Asio that was introduced by the French zoologist Mathurin Jacques Brisson in 1760.
Eleven subspecies are recognised:
A. f. flammeus – (Pontoppidan, 1763): the nominate subspecies, found in North America, Europe, North Africa and northern Asia
A. f. cubensis – Garrido, 2007: found in Cuba
A. f. domingensis – (Statius Müller, 1776): found on Hispaniola
A. f. portoricensis – Ridgway, 1882: found in Puerto Rico
A. f. bogotensis – Chapman, 1915: found in Colombia, Ecuador and northwestern Peru
A. f. galapagoensis – (Gould, 1837): found on the Galápagos Islands
A. f. pallidicaudus – Friedmann, 1949: found in Venezuela, Guyana and Suriname
A. f. suinda – (Vieillot, 1817): found from southern Peru and southern Brazil to Tierra del Fuego
A. f. sanfordi – Bangs, 1919: found on the Falkland Islands
A. f. sandwichensis – (A. Bloxam, 1827): Pueo or Hawaiian short-eared owl - found on the Hawaiian Islands
A. f. ponapensis – Mayr, 1933: found on eastern Caroline Island


The short-eared owl is a medium-sized owl measuring 34–43 cm (13–17 in) in length and weighing 206–475 g (7.3–16.8 oz). It has large eyes, a big head, a short neck, and broad wings. Its bill is short, strong, hooked and black. Its plumage is mottled tawny to brown with a barred tail and wings. The upper breast is significantly streaked. Its flight is characteristically floppy due to its irregular wingbeats. The short-eared owl may also be described as "moth or bat-like" in flight. Wingspans range from 85 to 110 cm (33 to 43 in). Females are slightly larger than males. The yellow-orange eyes of A. flammeus are exaggerated by black rings encircling each eye, giving the appearance of them wearing mascara, and large, whitish disks of plumage surrounding the eyes like a mask.


Short-eared owls have a scratchy bark-like call. Raspy waowk, waowk, waowk or toot-toot-toot-toot-toot sounds are common. A loud eeee-yerp is also heard on breeding grounds. However, short-eared owls are silent on the wintering grounds.


Through much of its range, short-eared owls occurs with the similar-looking long-eared owl. At rest, the ear-tufts of the long-eared owl serve to easily distinguish the two (although long-eared owls can sometimes hold their ear-tufts flat). The iris-colour differs: yellow in the short-eared, and orange in the long-eared, and the black surrounding the eyes is vertical on the long-eared, and horizontal on the short-eared. Overall the short-eared tends to be a paler, sandier bird than the long-eared. There are a number of other ways in which the two species the differ which are best seen when they are flying: a) the short-eared often has a broad white band along the rear edge of the wing, which is not shown by the long-eared; b) on the upperwing, short-eared owls' primary-patches are usually paler and more obvious; c) the band on the upper side of the short-eared owl's tail are usually bolder than those of the long-eared; d) the short-eared's innermost secondaries are often dark-marked, contrasting with the rest of the underwing; e) the long-eared owl has streaking throughout its underparts, whereas on the short-eared the streaking ends at the breast; f) the dark markings on the underside of the tips of the longest primaries are bolder on the short-eared owl; g) the upper parts are coarsely blotched, whereas on the long-eared they are more finely marked. The short-eared owl also differs structurally from the long-eared, having longer, slimmer wings: the long-eared owl has wings shaped more like those of a tawny owl. The long-eared owl generally has different habitat preferences from the short-eared, most often being found concealed in areas with dense wooded thickets. The short-eared owl is often most regularly seen flying about in early morning or late day as it hunts over open habitats.


The short-eared owl occurs on all continents except Antarctica and Australia; thus it has one of the most widespread distributions of any bird. A. flammeus breeds in Europe, Asia, North and South America, the Caribbean, Hawaii and the Galápagos Islands. It is partially migratory, moving south in winter from the northern parts of its range. The short-eared owl is known to relocate to areas of higher rodent populations. It will also wander nomadically in search of better food supplies during years when vole populations are low. (See a map of the short-eared owl's distribution across the New World.)


Sexual maturity is attained at one year. Breeding season in the northern hemisphere lasts from March to June, peaking in April. During this time these owls may gather in flocks. During breeding season, the males make great spectacles of themselves in flight to attract females. The male swoops down over the nest flapping its wings in a courtship display. These owls are generally monogamous.
The short-eared owl nests on the ground in prairie, tundra, savanna, or meadow habitats. Nests are concealed by low vegetation, and may be lightly lined by weeds, grass, or feathers. Approximately 4 to 7 white eggs are found in a typical clutch, but clutch size can reach up to a dozen eggs in years when voles are abundant. There is one brood per year. The eggs are incubated mostly by the female for 21–37 days. Offspring fledge at a little over four weeks. This owl is known to lure predators away from its nest by appearing to have a crippled wing.


Hunting occurs mostly at night, but this owl is known to be diurnal and crepuscular as well. Its daylight hunting seems to coincide with the high-activity periods of voles, its preferred prey. It tends to fly only feet above the ground in open fields and grasslands until swooping down upon its prey feet-first. Several owls may hunt over the same open area. Its food consists mainly of rodents, especially voles, but it will eat other small mammals such as mice, ground squirrels, shrews, rats, bats, muskrats and moles. It will also occasionally predate smaller birds, especially when near sea-coasts and adjacent wetlands at which time they attack shorebirds, terns and small gulls and seabirds with semi-regularity. Avian prey is more infrequently preyed on inland and centers on passerines such as larks, icterids, starlings, tyrant flycatchers and pipits. Insects supplement the diet and short-eared owls may prey on roaches, grasshoppers, beetles, katydids and caterpillars. Competition can be fierce in North America with the northern harrier, with which the owl shares similar habitat and prey preferences. Both species will readily harass the other when prey is caught.
Because of the high pH in the stomach of owls they have a reduced ability to digest bone and other hard parts, they eject pellets containing the remains of their prey.


It is listed as declining in the southern portion of its US range. It is common in the northern portion of its breeding range.
It is listed as endangered in New Mexico. Its appearance at the Calverton Executive Airpark on Long Island has prompted the New York State Department of Environmental Conservation to take the lead on ruling whether a massive redevelopment of the airport will receive the necessary environmental permits.


The long-eared owl (Asio otus), also known as the northern long-eared owl or, more informally, as the lesser horned owl or cat owl, is a medium-sized species of owl with an extensive breeding range. The scientific name is from Latin. The genus name Asio is a type of eared owl, and otus also refers to a small, eared owl. The species breeds in many areas through Europe and the Palearctic, as well as in North America. This species is a part of the larger grouping of owls known as typical owls, of the family Strigidae, which contains most extant species of owl (while the other taxonomic family of owls are the barn owls, or Tytonidae).
This owl shows a partiality for semi-open habitats, particularly woodland edge, as they prefer to roost and nest within dense stands of wood but prefer to hunt over open ground. The long-eared owl is a somewhat specialized predator, focusing its diet almost entirely on small rodents, especially voles, which quite often compose most of their diet. Under some circumstances, such as population cycles of their regular prey, arid or insular regional habitats or urbanization, this species can adapt fairly well to a diversity of prey, including birds and insects. All owls do not build their own nests. In the case of the long-eared owl, the owls generally utilizes nests that are built by other animals, with a partiality in many regions for those built by corvids. Breeding success in this species is largely correlated with prey populations and predation risks. Unlike many owls, long-eared owls are not strongly territorial nor sedentary. They are partially migratory and, although owls appear to generally use the same migratory routes and wintering sites annually, can tend to appear so erratically that they are sometimes characterized as “nomadic”. Another fairly unique characteristic of this species is its partially for regular roosts that are often shared by a number of long-eared owls at once. The long-eared owl is one of the most widely distributed and most numerous owl species in the world, and due to its very broad range and numbers it is considered a least concern species by the IUCN. Nonetheless, strong declines have been detected for this owl in several parts of its range.


The long-eared owl was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae under the binomial name Strix otus. This owl is now assigned to the genus Asio that was introduced by the French zoologist Mathurin Jacques Brisson in 1760.
Owls in the genus Asio are sometimes commonly referred to as eared owls. Despite the extensive modern distribution of the species, only eight modern species are thought to exist. Four species are found both in Eurasia and Africa and in the Americas, including the long-eared owl and short-eared owl in both. Despite similarities and being considered as in the same genus, it was found in a study utilizing electrophoresis that the genetic distance between long-eared owls and short-eared owls was unusually large for species within the same genera. Notwithstanding fossil records of Asio species showing the species presence during prehistory in locations like Kansas and Idaho (Asio brevipes) and California (Asio priscus), the exact origins of the long-eared owl are unknown nor their area of evolutionary origin and are unlikely to ever be known. At least three modern species represent related derivations, possibly with long-eared owls as the paraspecies or with the long-eared as part of a species complex that potentially bear a basal common ancestor. In all three cases, the related owls are obviously more tropical in distribution and adapted to more humid conditions, with darker plumage and are larger bodied with apparently stronger feet and more overdeveloped talons, possibly exploiting a more or less unoccupied ecological niche against competing owls. One of these three is the Stygian owl, which is the darkest derivation of all and readily known to be distinct for some time. The other two slightly larger, tropical species possibly housed in a species complex with the long-eared owls were at one time considered to be part of the long-eared owls species. One of these is the Madagascar owl (Asio madagascariensis), obviously endemic to the island of its name, while the other is the Abyssinian owl (Asio abyssinicus), native to east Africa especially in the northern area such as Ethiopia. While the marsh owl of Africa is outwardly very similar to and likely closely related to the short-eared owl, the striped owl (Asio clamator) is somewhat of an outlier among living Asio species and of mysterious origin, despite being genetically related to the other Asio, does not appear to be a close cousin of other living species. Studies of the mitochondrial genome found that the Asio genus, and consequently the long-eared owl, diverged most recently among living owl groups from the Otus or scops owls genus, with a more distant branch division from the Strix genus. A study of the genetic homogeny of long-eared owls in a single roost site was shown to be slightly higher than between different roosts. However, this homogeny is relatively low for a communal roosting bird in general.


Four subspecies of the long-eared owl are recognised.
A. o. otus (Linnaeus, 1758)- This is the nominate subspecies and is distributed throughout the species’ range in the Palearctic. They may be found as far west as the Azores, northwestern Africa, the Iberian Peninsula and the British Isles through as far east as Sakhalin, Japan and northern China. Some populations of this race may winter as far south as in Egypt, Pakistan, northern India and southern China. The wing chord of the nominate subspecies may range between 263 and 313 mm (10.4 and 12.3 in) and tail length may be between 132 and 165 mm (5.2 and 6.5 in). Size appears to increase slightly from west to east, with owls in China being about 4% larger winged than those from Europe. Despite there being no known published weights for eastern/Chinese long-eared owls, they appear to obtain the largest sizes within the species. In this subspecies, the facial disc tends to be pale ochraceous tawny, rimmed black with relatively short eyebrows that are marked whitish or absent entirely of markings. The erectile ear-tufts are prominent, being colored mainly blackish-brown with tawny edges. The upperparts are ochraceous-tawny, finely peppered with dusky spots and blackish streaks on a grey "veil", while the crown is finely mottled to dusky. The nape and hindneck bear dusky shaft-streaks with the feather outer webs of the scapulars being whitish, forming a row across the shoulder. Primaries basally are uniformly ochraceous-tawny, distally barred light and dark, while the secondaries are barred ochraceous and dusky. The tail is typically tawny with a greyish wash, overlaid with 6-8 very narrow dark brown bars. The underparts have a base colour of ochre, with the foreneck and upper breast marked with blackish-brown streaks; these becomes paler below and marked with dusky shaft-streaks and narrow cross bars. The underwing has distinctive barring and dark comma-like markings at the wrist (conspicuously lacking on overlapping Eurasian short-eared owls). The eyes tend to be yellowish-orange to orange, but occasionally may be chrome yellow. The cere is brownish-flesh, the bill is grey and the talons are blackish-grey. In this subspecies, the downy chick is whitish with pink skin, while the mesoptile plumage is fluffy greyish to brownish-white with diffusely barred dusky flight and tail feathers, being similar to adults but with the ear tufts not yet developed.
A. o. canariensis (Madarász, 1901)- This subspecies is endemic to the Canary Islands. With a wing chord measurement of 257 to 284 mm (10.1 to 11.2 in), this is seemingly the smallest subspecies of the long-eared owl. This race averages darker than most long-eared owls of the nominate subspecies, bearing heavier and sharper dark markings overall. Furthermore, the Canary Island long-eared owls tend to have brighter reddish-orange eyes.
A. o. wilsonianus (Lesson, 1830)- This subspecies is found in south central and south east Canada (Manitoba to Nova Scotia) south to southern USA (north Oklahoma and Virginia). The wing chord typically measures 284 to 305 mm (11.2 to 12.0 in). In general, American long-eared owls are more vividly marked than many Eurasian populations. The facial disc is bright rufous, with a strong blackish rim and extensive white about the disc. The eyes are typically a deep yellow. Meanwhile, the markings on the underside usually are quite blackish and prominent with distinct cross bars.
A. o. tuftsi Godfrey, 1948 - The range is western Canada (south Yukon to southwest Manitoba) south to south central USA (west Texas). It differs from A. o. wilsonianus in having paler plumage. The brown mottling on upper parts is paler and more restricted. It is weakly differentiated and may compromise clinal variations due to region and habitat, rather than subspecific differences.


This species is a rather slim and long winged owl with usually prominent erectile ear tufts, which are positioned closer to the center of the head than in many other types of owl. The purposes of ear tufts are not definitively known and are present in about half of living owls. Arguably the most popular theory amongst biologists and ornithologists is that ear tufts could be a means of intraspecies communication of intent and mood. In general coloration, the long-eared owl is often considered a hue of ochraceous-tawny with a grayish or brownish wash variably manifesting. The base color is commonly overlaid with variable blackish vertical streaks (and occasionally spots), which are usually more apparent about the wings and back. The scapulars are usually marked whitish, which provide further contrast when seen against the base color and blackish markings. The wing's dark carpal patches can also display broad panels of buff or almost orange on the wings across the base of primaries, which represent a more richly emphasized version of a pattern shared with other owls that tend to be vole-hunting specialists, like short-eared owls (Asio flammeus) and great gray owl (Strix nebulosa). On the underside, the body tends to be a somewhat paler ochraceous-tawny compared to the upperside. Long-eared owls tend to have dusky streaks on the upper breast, below which they may be heavily marked with herring bone pattern (which is created by dusky shaft-streaks and crossbars on these feathers). There is much individual and regional variation in markings with owls dwelling in more extensively forested regions tending to be of a darker hue, often so densely washed above as to appear largely dusky brown on the back and the underside largely overlaid with bolder dusky-blackish marks. Meanwhile, in some desert-like regions, the plumage may tend towards a somewhat more washed out look, at times appearing fairly cream or yellowish, with sparser and lighter dusky markings overall. The facial disc is visibly well developed and variably colored (see subspecies) in the species, rimmed dusky often with white running down along the center through the bill, while at times the white lines form a “moustache” and/or extending to the inside of the facial disc rim. The ear tufts are usually dusky in front and paler tawny on the back.  Long-eared owl possess a blackish bill color while its eyes may vary from yellowish-orange to orange-red, tarsi and toes feathered.
The long-eared owl is a medium-sized owl, which measures between 31 and 40 cm (12 and 16 in) in total length. Their wingspan is relatively large for their size, measuring 86 to 102 cm (2 ft 10 in to 3 ft 4 in). However, compared to other widespread owls considered of medium size and to which they can appear broadly similar in size, such as barn owl (Tyto alba), short-eared owls and tawny owls (Strix aluco), the long-eared owl is quite a bit lighter and slenderer bodied, with mature weights around half of those of tawny owls not being uncommon. As expected in owls and birds of prey in general, long-eared owls display reverse sexual dimorphism in which females are usually slightly larger than males (to the contrary of most non-raptorial birds). Males furthermore may tend to be somewhat paler in plumage than females. In Finland, one survey of the body mass of mature birds found that 22 males averaged 288 g (10.2 oz) while 20 females averaged 327 g (11.5 oz). In body mass, European long-eared owls per a study were shown to run contrary to Bergmann's rule (that widespread animals should be smaller closer to the Equator) as body mass seemed to increase further south, being lightest in Sweden, where 37 males averaged 197 g (6.9 oz) and 24 females averaged 225 g (7.9 oz), intermediate in Denmark and heaviest in the Netherlands, where 21 males averaged 256 g (9.0 oz) and 24 females averaged 308 g (10.9 oz). In migratory owls largely from Scandinavian summer grounds in England, the average weight of 8 males was 263.6 g (9.30 oz) and the average of 28 females was 294.7 g (10.40 oz). Meanwhile, in various studies in North America, 38 males (in Montana) were found to average 245.3 g (8.65 oz), 55 males (also Montana in a different study) to average 261 g (9.2 oz) and 15 males (from Idaho) 232 g (8.2 oz). From the same studies, respectively, 28 females averaged 279.4 g (9.86 oz), 49 females averaged 337 g (11.9 oz) and 19 females averaged 288 g (10.2 oz). Museum specimens in North America were found to average 245 g (8.6 oz) in 38 males and 279 g (9.8 oz) in 28 females, while 520 migrating adults in Duluth, Minnesota averaged 281.1 g (9.92 oz). In all, long-eared owl males may vary in weight from 160 to 330 g (5.6 to 11.6 oz) while females may vary from 180 to 435 g (6.3 to 15.3 oz).
In standard measurements, long-eared owls vary in wing chord length from 262 to 315 mm (10.3 to 12.4 in) in males, with 883 in North America averaging 285.1 mm (11.22 in), and 255 to 332 mm (10.0 to 13.1 in) in females, with 520 American ones averaging 286.2 mm (11.27 in). The tail may measure 121.5 to 161 mm (4.78 to 6.34 in) in males and 143.5 to 165 mm (5.65 to 6.50 in) in females, with 1,408 owls averaging 146.3 mm (5.76 in). Less widely measured are bill length, which averaged 15.7 mm (0.62 in) in males and 16.2 mm (0.64 in) in females from North America, and tarsus length, which averaged 38.2 mm (1.50 in) in 20 males and 39.9 mm (1.57 in) for 16 females from Europe, with a range in both sexes of 36.9 to 42.3 mm (1.45 to 1.67 in). In terms of their skeletal structure, it bears a relatively wide skull but relatively small eyes and orbits, while the beak is relatively elongated but weak. The legs are relatively long and thin and, while needle-sharp, the talons are relatively fine and the feet relatively weak for an owl. However, the talons are still highly proficient at drawing blood if contact is made with human skin.


If seen well, an experienced observer is usually able to distinguish a long-eared owl by combination of its field marks, size and coloration. However, some potential owl species may be confused for them. Stygian owls (Asio stygius) (which barely overlap perhaps in northern Mexico) is larger with partially bare toes and generally darker with inky and more boldly patterned plumage, with often nearly the enter facial mask appearing off-black. Tawny owls, which co-exist with long-eared owls in Eurasia, are unlikely to be mistaken given that they usually appear considerably rounder and bulkier overall (and are indeed slightly larger and much heavier), further possessing a much broader, more rounded head. The tawny species has no ear tufts, eyes of blackish-brown colour and relatively shorter wings. In flight, tawny owls show well-fingered primaries (with five apparent emarginations) unlike the squared off wings of the long-eared owl. The Eurasian eagle-owl (Bubo bubo) is far larger and more massive than a long-eared owl with visibly more overdeveloped and  powerful-looking feet and talons and a huge squared-off-looking head with the ear tufts set nearer to the edge. The eagle-owl is often more heavily patterned on the crown and back with heavy blackish marking but has a less strongly demarked (and shallower) facial disc when compared to the long-eared. In some parts of the wintering range, other eagle-owls may scarcely abut the wide range of long-eared owls in Eurasia (and perhaps Northwestern Africa) but are usually distinguishable (similarly as in the Eurasian species) by size differences, plumage characteristics and, occasionally, habitat preferences. Asian fish owls, which are essentially a subset of eagle-owls, are generally also much larger than long-eared owls with tousled looking ear tufts, have less variable coloring and often have feathering over only part of their tarsi. In North America, great horned owls (Bubo virginianus), yet another type of eagle-owl in all but name, have a squarish head and more widely separated ear tufts. Like other Bubo species, great horned owls are also perceptibly larger and more massively built than any long-eared owl (despite being smaller than the Eurasian eagle-owl). Great horned owls also have typically heavily barred, rather than streaked, underparts. Scops and screech owls are much smaller than long-eared owls, as well as differently marked (often with more individual varying overall coloring, i.e. from gray to brown to rufous) and usually have rather short ear tufts. Marsh owl (Asio capensis) (rare overlap perhaps in northern Morocco) is generally brown with quite different looking fine mottling or barring below and has brown eyes and tiny ear tufts.
Over much of its range, long-eared owls occur with the related short-eared owl, the latter species averaging slightly larger. Much has been written about distinguishing them in the field, though, if seen well, the resemblance between the species is not particularly strong. Furthermore, the two species differ in habitat preferences, with the short-eared owl often favoring (where available) any kind of entirely treeless, open habitats (including many wetlands and Arctic tundra as well as steppe, prairie and extensive meadows), often avoiding the edge habitats favored by the long-eared. However, in dim light, at a distance or in flight, confusion is certainly possible. In both long-eared and short-eared owls, the flight style when seen has a distinctive, erratic and buoyant flapping quality that many birdwatchers considered reminiscent of a moth. At rest, the ear-tufts of the long-eared owl serve to easily distinguish the two (although long-eared owls can sometimes hold their ear-tufts lax). The iris-colour differs: yellow in short-eared, and often orange in long-eared. Furthermore, the black surrounding the eyes is vertical and slight on the long-eared, and horizontal and far more conspicuous on the short-eared. Overall, the short-eared owl tends to be a paler, sandier-looking bird than the long-eared, lacking the darker and more extensive markings of the latter.  There are a number of other ways in which the two species differ which are best seen when they are flying. Short-eared owls often have a broad white band along the rear edge of the wing, which is not shown by long-eared owls. On the upperwing, the short-eared owl's primary-patches are usually paler and more obvious. The band on the upper side of the short-eared owl's tail are usually bolder than those of the long-eared. The short-eared's innermost secondaries are often dark-marked, contrasting with the rest of the underwing. The long-eared owl has streaking throughout its underparts whereas on the short-eared the streaking ends at the breast. The dark markings on the underside of the tips of the longest primaries are bolder on short-eared owls. The upperparts of short-eared owls are coarsely blotched, whereas on the long-eared they are more finely marked. The short-eared owl also differs structurally from the long-eared, having longer, slimmer wings. The shorter and broader wings in combination with a squarer tail in long-eared owls produce proportions more reminiscent of a buzzard than the short-eared.  When studied by their osteological features, however, the long-eared and short-eared owls are difficult to distinguish.


The long-eared owl has relatively large ear slits placed asymmetrically on the sides of its head, as in a majority of owls, with the left ear higher and right lower in order to allow them to absorb sound both from above and below. The ear slit very nearly occupy the full height of the skull, being are about 38 mm (1.5 in), long and covered in movable skin flaps. The right ear is about 13% larger based on freshly dead owls. Due to its ear structure, the hearing of a long-eared owl is around ten times better at hearing high and medium pitches than humans. Barn owls and boreal owl (Aegolius funereus) have (via convergent evolution) roughly similar ear structures, with the relative size of the ear structure and facial disc in owls generally indicative of the level of importance of acute hearing to their life history. Owls with relatively smaller ear slits and shallower or vestigial facial discs tend to skew towards more crepuscular or partially diurnal behaviors, whereas owls such as long-eared owls are more or less entirely nocturnal. It is well known that a majority of owls can hunt in darkness due to their extraordinary hearing, which allows them to pinpoint locations of prey, but they can also utilize their hearing to track intraspecific calls and activities and avoid predation risks.
The vocalizations of this species are highly variable. Amongst owls of all ages, long-eared owls in Michigan were recorded to have made 23 different vocalizations. Karel Voous considered them to likely be the most diverse vocalists of all owl species in the Northern hemisphere. The song of the male long-eared owl is a deep whoop, which is repeated at intervals of several seconds. It starts with some hoots at slightly lower pitch before reaching full volume and quality. On calm nights, this song may carry over up to 1 to 2 km (0.62 to 1.24 mi) away (at least to human auditory perception). The song of the male is around 400 hertz. In North America, some observers have considered the male's song as analogous to the deep cooing of band-tailed pigeons (Patagioenas fasciata). Females gives a weaker, less clear and much higher pitched song with a nasal quality. In nearly all owl species, the females, despite being typically the larger sex, have smaller syrinx than the males and so tend to have less powerful voices. The call of the female is at times compared to a weak tin whistle and is only audible at close range, being about 4-5 halftones higher than the song of the male. Females usually call only in duet with male during courtship, but also when the nest is selected and around the beginning of incubation (probably in conjunction with food-begging). In fact, close study has revealed that female calling may occur as frequently as every 2–8 seconds at times of night between nest selection and egg laying. Both sexes utter a cat-like, somewhat hoarse jaiow notes or high yip-yip notes, the latter reminiscent of a call made by barn owls. When disturbed near the nest holding young, both parents may utter a series of tinny tones, watt-watt-watt-watt. During the period of courtship the male flies around and flaps its wing around, producing a clapping sound. During the display flight, the male may make as many as 20 claps. As with many owls, all ages may produce hissing sounds and bill snapping when they feel threatened, especially in the context of nesting. Fledging young call all with high-pitched, drawn-out notes, variously transcribed as feek, peeyee and pzeei, and are often likened to the noise of a gate swinging on a rusty hinge.


The long-eared owl has an extremely large distributional range. In Eurasia, they are distributed from the Iberian Peninsula and the British Isles (including almost the entirety of Ireland), in both of which they are found somewhat spottily but quite broadly, especially for an owl. From western France east through the remainder of Europe they are found nearly everywhere, though still usually quite common in these areas, there are small spots where they do not usually occur in Italy, Austria and Southeastern Europe. In Scandinavia they are found only as a breeding species in about the southern two-thirds of Norway, Sweden and Finland while they usual persist year around in haunts in the southern tips of Norway and Sweden, respectively, as well as in all of Denmark. In coastal Norway they are found at their worldwide northern limit as breeding bird, with long-eared owls nesting as far north as in the Subarctic zone of Troms. In latitudinal range, they are found as far south the Azores, the Canary Islands while their limited breeding range in north Africa is from Morocco to Tunisia, as well as seemingly in northernmost Algeria. Out of Europe, they are found very spottily as breeders in Turkey, northernmost Syria, Israel and Lebanon. They are quite broadly distributed within Russia, breeding in about the southern two-thirds of the country (north as far as roughly Chernyshevsky and Yakutsk) and often occurring year around in about the southern third of it (north to about the cities of Perm, Tyumen and Tomsk) and east to Siberia, ranging far as Sakhalin. Their range is continuous from Russia into most of Kazakhstan, Georgia, Kyrgyzstan, about half of Uzbekistan and infrequently into northern Afghanistan and Turkmenistan. In the east, they range through most of Mongolia (absent from the southwest) and the western and eastern parts of northern China, with seasonally uncertain status in the Koreas. Long-eared owls are found throughout the islands of Japan but mainly winter only in points south of Osaka. The long-eared owl occurs apparently only in winter in small spots of southern France, southern Greece, northwestern Egypt, northern Iran, southern Turkmenistan, broadly in much of Afghanistan, Pakistan and northern India (such as the Kutch, Punjab, Kashmir), as well as to the east in Bhutan, southern China, Taiwan and most of South Korea. Irruptive wanderings have resulted in vagrant long-eared owls in various places such as the Faroe islands, Iceland and Madeira as well as Ryukyu Islands in the east.
This species is found widely distributed in North America as well. Their northern limits are reached in much of British Columbia, though they are mainly absent from the western and coastal part, with the breeding range scarcely spilling over into the southern part of the Northwest Territories. As is the case in most of Eurasia, they are usually found at up to 50 degrees north. Long-eared owls are also found breeding in most of Alberta, all but northern Manitoba and southern Ontario and Quebec only to the southernmost part of the Hudson Bay. However, with the exception of inland southern British Columbia, southern Alberta, and the southern parts of Ontario and Quebec, as well as an isolated population in Newfoundland, long-eared owls usually vacate their Canadian range during winter. The species range as a breeding species is far more extensive in the west than the east within the United States. They breed in Washington, Montana and North Dakota mostly continuously to much of California, where habitat is appropriate, Arizona, western Colorado and western New Mexico as well as less broadly in South Dakota and Iowa. Even though they are absent from the Pacific coasts in Washington and Oregon, they may be found breeding along the Pacific in southern California and even Baja California in Mexico. The first record of breeding for mainland Mexico was recorded for an incidental observed nest built by owls in Janos Biosphere Reserve in Chihuahua. They also breed and occur year around in most of Minnesota, Wisconsin and Michigan. Breeding and/or year around occurrence is very rare in the eastern U.S. with a few records of them nesting in Maine, Virginia and West Virginia.  The long-eared owl occurs much more broadly in North America during the non-breeding season and may found essentially all over the Midwest, Texas and as far south in Mexico as Colima, Veracruz and northern Oaxaca. The species also occurs in the non-breeding season in Louisiana (but for the southeast) and much of northern Mississippi, Alabama, Georgia and South Carolina north to Illinois, Indiana, Ohio and southern Pennsylvania. Very rarely, these birds have turned up in Florida (in times of exceptional irruption) and, as a vagrant, even the Bermudas. They are found also by winter and in migration in much of the east coast of the United States, from the Outer Banks in North Carolina, broadly in eastern Pennsylvania and almost anywhere in Delaware or New Jersey, southeastern New York (including New York City) and north to much of southern New England including almost all of Connecticut, Massachusetts and Rhode Island as well as southern New Hampshire.


Long-eared owls are more or less strictly nocturnal in activity. Usually activity for the species commences at dusk. After nightfall long-eared owls in Idaho were least active from 8-10 pm and from 5-6 am, while the hours around 10-12 pm and 3-5 am were often the peak times of activity. When living relatively close to the Arctic, long-eared owls may be forced to forage during daylight as no full nightfall may occur during summer. When flying by day, long-eared owls are often mobbed by diurnal birds such as corvids and other birds of prey. Often long-eared owls will discharge a fairly large amount of pellets and drop them below regular day roosts. Unlike most other owls, the species has no territorial hunting ground. In Switzerland, 14 long-eared owls examined using radiotelemetry were found to have an average home range of 980 ha (3.8 sq mi). In the study, they required fields along borders of woodlands, avoiding completely treeless areas more so than they were prevalent in the environment. In the České Budějovice area of Czech Republic, 9 radiotagged owls were studied. Nearly equal numbers were found in suburban and urban areas, and urban ones used developed areas for more than 50% of their nocturnal activity while suburban ones used developed areas for less than half of their activities. Similar habitats were favored by both urban and suburban owls but urban owls had to range wider to avoid heavy human activity and access city parks and so had larger average ranges, 446 ha (1.72 sq mi) vs 56 ha (0.22 sq mi), while suburban ones had easier access to meadows and stands of woods.


Out of roughly 19 regular species of owl in North America and 13 regular species of owl in Europe, the long-eared owl is classed as one of the five in both continents to be truly migratory, moving annually in at least some areas and in some numbers from summer to winter grounds and back whether or not it is an irruptive year. Northern populations are migratory, showing a strong tendency to wander south in autumn. Some normally young bird from central Europe migrate southwest at distances of up to more than 2,000 km (1,200 mi). Central European adults are less migratory, at most merely wandering in winter. Long-eared owls that breed Scandinavia generally migrate to nearly anywhere in Europe, from Great Britain to Southeast Europe, though some may disperse as far as north Africa or Asia Minor. In Europe, males and females seem to differ slightly in migratory behaviour. Long-eared owls wintering in Denmark were found to be heavily biased towards females, also there is a bias towards females in winter surveys in other areas such as southern Sweden. At 10 wintering sites in Europe, females were 36% more common than males. The hypothesis posited by those that studied the owls in Denmark is that females face a higher rate of predation by larger birds of prey and may distribute away from Fennoscandia where densities are high of those predators and to areas that show low densities of these predators. Another, non-exclusive, theory is that they may be avoiding areas with deep snow that may inhibit prey capture. Supporting data that male long-eared owls winter further north than females was gathered in southern Norway, where the recovery of dead owls (from car or powerline collisions) of the species encountered in late fall throughout winter, males were 45% more common than females. On evidence, many of the females that vacate Norway and even Fennoscandia come to winter in Great Britain (the female migrants here being up to 3.5 times more common during winter than male migrants in one study). Two birds in ringing studies that were recorded in late winter in Germany were observed to return for the summer to central Russia (near Yaroslavl, 2,050 km (1,270 mi) away) and to eastern Russia (near Kazan, 2,410 km (1,500 mi) away). Birds that breed in central Asia have been recorded to winter in a wide variety of locales, including the Egyptian Nile valley, Pakistan, northern India and southern China. In North America, migrants generally sourced from Canada and the Upper Midwest winter almost anywhere in the remaining United States, however they will irruptively migrate as far as Georgia and several areas of Mexico and seldom in Florida. Typically the northern limit of the wintering range fall up to the Okanagan Valley of British Columbia, the southern reaches of the Upper Midwest and central New England. Spring migration was tracked along with northern saw-whet owls (Aegolius acadius) as they migrated through Oswego County, New York via mist nets, with the saw-whet considerably outnumbering long-eared owls. Here, migration of long-eared owl was between March 21 and April 14 and, unlike the saw-whets, the long-eared owl migration does not appear to be effected as extensively by weather conditions. Long-eared owls are 19.5% of owls (or 197 total owls) recorded migrating through Cape May Point in fall (against a majority, 60.6%, being saw-whet owls), with 26.1% of the specimens from the species caught in the mist nets being adults. More than 90% of long-eared owls migrate between mid-October and late November, with the immatures migrating earlier, 52.1% of juveniles having passed through in October whereas only 9.4% of adults migrated in the month. Cape May studies also indicated that 58.87% of long-eared owls were caught in the dark before dawn rather than other times of night. Based on evidence from Cape May, migrating long-eared owls tend to fly higher above the ground than do migrating saw-whet and barn owls but not as high as the short-eared owl, with the latter owl often able to avoid mist nets apparently via its flying height while moving through. Per a study in Idaho, 7 radio-tagged owls actually migrating both north, 75 to 125 km (47 to 78 mi) north of their respective nesting sites, and to higher elevations after the breeding season (in many cases possibly to exploit displaced rodents in recently logged areas).
The long-eared owl has the peculiar ability to increase populations and then disperse in nearly multi-directional movements during good years for prey numbers. Banding records across North America show highly erratic numbers and movements across the continent of North America with unpredictable peak numbers of migrants in completely different years respectively for the states of Wisconsin, Michigan, New York and New Jersey. Therefore, the species is sometimes considered “nomadic” despite many populations of the species being consistent annual migrants. Similar tendency towards so-called “nomadism” is shared by other widespread raptors semi-specialized to hunting voles over open ground, such as short-eared owls and hen harriers (Circus cyaneus). These erratic movements and peaks and ebbs of northern populations has lent to descriptions of the long-eared owl as “irruptive”, however it generally moves in quite different ways from owls largely endemic to the taiga (or tundra), which are more traditionally irruptive in that they tend to migrate little or not at all when prey remain ample in their native home range but then move south in mass when prey populations crash. Long-eared owls, unlike these irruptive northern owls, often migrate from the northern areas regardless of conditions. However, like the northern irruptive owls, long-eared owls tend to appear in unprecedented numbers to the south when a peak prey year is followed by a winter during which prey population crashes. In North America, the migratory habits of long-eared owls are strongly mirrored by those of northern saw-whet owls. Study of banding records in Saskatchewan show that the long-eared owl Canadian populations may be considered more truly irruptive species both as a breeder and migrant in that only appears in numbers during peak vole years, with large numbers only in 4 of 44 banding years. During 7 low years, the long-eared owls of Saskatchewan seemed to disappear altogether from much of the province. Peak years also coincided often with snowshoe hare (Lepus americanus) peaks, possibly due to lessened competition (as the larger owls favored prey is locally the hare) and interspecific predation by great horned owls. The phenomena of movements that seem to be nomadic or purportedly irruptive in nature may occur as well in Europe, though given the species’ denser population in general there in comparison to North America may result in less noticeable wide variations in numbers. Years with irruptive numbers of long-eared owls have been noted in the British Isles when prey peaks then crashes back in Scandinavia, resulting in much larger numbers of migrant long-eared owls into the islands than normal, as well as concurrently large numbers of short-eared owls and harriers. In southern Finland during a peak prey year followed by a prey crash, a very large number of long-eared owls were detected and were seen to be likely food stressed, as several were foraging actively during daylight despite the extensive nighttime hours during the season.