Spring flowers in Auckland Domain
Auckland Museum has more than 350,000 herbarium specimens in the collection, and over 250,000 herbarium records can be viewed online. This article introduces a few plants very close to Auckland Museum, and explains the language botanists use to describe introduced species.
From the Cape to the Domain
Sparaxis (Sparaxis bulbifera) is an iris native to South Africa. It's a summer-green perennial that flowers in the spring, fruits and then dies down back into its corm for the winter.
In 1971, the earliest sparaxis collection the Museum holds from the Auckland Domain was found "wild under trees" by Alan Esler and Sandra Astridge. The plant has since spread - mainly by the cormils (small bulbs) produced in their leaf-axils - throughout the Domain, in the lawns under trees and in the open.
The Auckland Museum herbarium holds 31 collections of sparaxis, most are of S. bulbifera. You may have seen the colourful species of sparaxis S. tricolor, which is more commonly cultivated in New Zealand.
The language of a botanist
Both S. tricolor and S. bulbifera were introduced to New Zealand as garden ornaments - which then escaped into the wild. This is the origin of most weeds in New Zealand. Botanists use the following language to help describe this process:
When a plant is planted and tended to by humans, it is cultivated.
An exotic plant is one not native to the country that it is growing in.
When a plant has naturalised, it means an exotic plant has adapted to our environment and is spreading without the aid of humans. The term weed is used for the most aggressive of the naturalised species.
Watsonia meriana, a tall South African iris of various colours, is just coming into flower now on the lower Domain Drive – replacing the earlier flowering chasmanthe. It was most likely originally planted here, but has now spread by itself into a dense population on the road bank.
Flowering in the Domain
Tracking introduced species
Part of the reason the Museum have so many specimens in the herbarium - including many of the same plant - is that botanists are constantly tracking the spread of introduced species, usually from the cities out into the natural environment.
In botany, a collection consists of a pressed plant specimen, usually fertile and with good location, habitat, abundance information, and now often field photos as well.
Also found in the Auckland Domain lawn is Cape weed (Arctotheca calendula), a daisy native to the Cape Province in South Africa and also neighbouring KwaZulu-Natal. It has naturalised widely throughout most of New Zealand.
The first wild New Zealand collection was by Thomas Kirk at Drury between 1863 and 1873, and the earliest one from the Auckland Domain was in 1974.
Pretty flowers for some,
a noxious plant for others
Cape weed has naturalised in many countries and is considered as a noxious plant in some of them. It is an annual and does best in warm sites on poor soil, usually in pasture, lawns, sand dunes and waste land.
This particular collection of Cape weed, by Patricia Aspin, was found in Kohekohe in October 2012. She made the following field notes:
"On dry sandstone areas near coastal cliffs, past pine plantation. Previous landowner introduced this plant to bare areas because she thought they were pretty and would survive the harsh environment! Slowly spreading - I've suggested that it be controlled. Not seen it elsewhere in the district."
The importance of ongoing collecting
By collecting naturalised introduced species, botanists can track their spread over time and monitor the potentially threatening effects on our native flora and fauna.
This helps the Department of Conservation, councils, landowners and conservation groups keep a close eye on our ever-changing environment.
Cite this article
Spring flowers in Auckland Domain. Auckland War Memorial Museum - Tāmaki Paenga Hira. First published: 22 October 2015. Updated: 7 April 2016.