Which Nettle?

Urtica urens, Urtica incisa
Family: URTICACEAE



Until recently, I believed that the only nettle found in the Toowoomba area was this plant, the native perennial Urtica incisa. It's a plant which can die back to its roots in winter, but regrows again in spring.
I was aware that the annual nettle Urtica urens had been introduced to Australia, but didn’t think it had found its way into this district.







Obviously I spend too much time in the bush, and not enough time in Toowoomba gardens!
I was shown Urtica urens in a West Street garden the other day.

It had made itself well and truly at home in a piece of fallow vegetable garden.  It’s just as well that such a rampant plant has a practical use, as a very good  green manure!
The garden’s owner was quite happy about having nettles, though, as she uses them in her herbal tea.
Both nettles have somewhat variable leaves, but the native Urtica incisa can be easily distinguished from the introduced plant by its flower heads. Note that in the upper photo, which shows the native nettle,  the stem on which the flowers grow is unbranched and as long as, or longer than, the leaf-stem. By contrast the flowers on the introduced nettle, (lower photo) are on much shorter stems and tend to branch.
( A double click on the photo lets you enlarge it, to see the details.)
For some of the many uses of nettles, see my blog of October 2008.