What is it? Common/wild/Fuller’s teasel and cutleaf teasel
What do the nerds call it? Dipsacus fullonum and Dipsacus laciniatus, respectively
Who is it related to? Caprifoliaceae family or honeysuckle
How can you tell it is what it is? The big, egg shaped spiky flower/seed cone atop a prickly stalk is a dead giveaway. The most basic way to tell the varieties apart would be that the wild teasel has purple flowers, and the cutleaf has white. These plants generally have a two year lifecycle where it starts as a low-lying rosette of leaves the first year, then creating the iconic stalk-with-death-egg the second year.
The rosette forms of the two species have similar general structures, though the leaf shape is drastically different. The wild teasel has a smoother outline, whereas the cutleaf have jagged, toothed edges, giving it its name.
A potential lookalike would be thistle, another spiky plant with many flowers on a cone that are a similar purple to the wild teasel. The immediate differences that I noticed were the general structure of the flower head, as well as the teasel having long bracts that form below the flower head and come up and around, like a thin cage. Thistles’ spikes also seem much more aggressive, mirroring its name in comparison to a slightly gentler sounding teasel.
Discussion: Before this week, I was only aware of teasel from photographing bugs on them (they seem to attract a lot of favorites), and I could barely even tell the difference between the teasel and thistle, let alone between teasel varieties. That changed this week, however, as my focus shifted from photographing the critters on them, to snipping their flowering heads off as part of a volunteer invasive removal program. While some of our natives like their nectar, teasels can take over the habitat that they prefer, wide open and sunny pasture-like habitats.
Due to rainwater collecting at the base of the leaves near the stalk, insects can sometimes become trapped, causing some to speculate that teasel is potentially partially carnivorous. It seems as this is a bit controversial though, as there are not other features that other carnivorous plants have, such as a separate digestive mechanism, plus it definitely does just fine without any of the extra nutrition if nothing ever drowns in the tiny pool.
The dried seed heads were historically used for “teasing” wool, an important step in the wool spinning process. They are also heavily used in dried floral arrangements, and can cause populations to spring in cemeteries, which are often sunny, wide open spaces as well.