OF THE WEEK
Dr. T. Ombrello - UCC Biology Department
Resurrection Plant, Rose of Jericho, Siempre Viva (meaning Everlasting)
Scientific name: Selaginella lepidophylla
Explanation of scientific name:
- from the Latin "selago" (A type of juniper we now call savin juniper. Selaginellas
have juniper-like foliage.), and the Latin "ella" meaning small.
- from the Latin meaning scaly-leaved.
The plant on the left has been kept moist.
The plant on the right has been kept dry.
Resurrection Plant is one of over 700 species in the Selaginella genus of
plants. All of them are primitive plants, fitting somewhere between mosses and
ferns in the hierarchy of plant evolution. They belong to a group of plants
known as the lycopods, whose members go by the common names of ground
pines and club mosses. All are relatively small (up to one foot tall) and are
found around the world, usually in moist locations with mosses and ferns. They
reproduce by single-celled spores, and lack flowers, fruits and seeds. Even
their "leaves" are not really leaves, but instead leaf-like extensions
of the stem. What lycopods consist of then are roots, stems with scales, and
club-like strobili that produce spores.
distinguishes the Resurrection Plant from most other lycopods is where it lives
and how it copes with its environment. Found from Texas and Arizona south to El
Salvador, the Resurrection plant is a desert inhabitant. Growing from rock
outcroppings or in dry soil, its close neighbors would be mostly cacti and other
arid-loving species. Under these conditions, most other lycopods would perish,
but the Resurrection Plant thrives.
the soil is moist after infrequent rains, a Resurrection Plant absorbs water and
grows rapidly, producing a flat rosette of scaly stems up to one foot across. As
the soil dries, it cannot store water like its succulent neighbors, so it folds
up its stems into a tight ball as it desiccates and goes into a state of
dormancy. The folded plant has a limited surface area, and what little internal
moisture is present is conserved. All metabolic functions are reduced to a bare
minimum and it appears to be dead. The plant can remain in this dormant
condition for years. When the rains return, the plant's cells rehydrate. The
stems unfold, metabolism increases, and growth resumes. Even dead Resurrection
plants will unfold if given water, since rehydrated cells expand even if there
is no living protoplasm in them.
Resurrection Plant's ability to seemingly return from the dead certainly
justifies its common name, and has led to its use as a novelty plant. Collected
from the wild in the South West US and Mexico, it is sold to tourists and
a lycopod, the Resurrection Plant can trace its ancestors far back into history.
They appeared at least 400 million years ago as small plants similar in
appearance to those that are alive today. Their period of prominence however,
came later. Between 345 and 280 million years ago they dominated the plant world
as giant trees over 100 feet tall with trunks 6 feet in diameter at the base.
These swamp inhabiting trees became important contributors to the coal deposits
we exploit today. Cooler climates and other as yet unidentified factors caused
these giant lycopods to become extinct. But their smaller relatives, like the
Resurrection Plant, persisted in a changing world.
Today the lycopods make up an inconspicuous remnant of what were once the largest plants on earth. The ability to adapt to one's surroundings has always been the key to survival. In that respect the seemingly insignificant Resurrection Plant is an eminent example of perseverance.