Yampah vs. Queen Anne's Lace

[Don Boucher]

Hello,

Yampah (Perideridia sp.) grows at the field next to the Jackson-Frazier Wetland parking area (a.k.a. Lancaster Natural Area). Last week there were many hundreds of plants blooming there. Lisa and I went back early this week to get photos but they mowed the area. Fortunately there are still a good number of plants blooming around the edges.

It's a native plant that can be overlooked because it looks very similar to Queen Anne's Lace (Daucus carota) and can appear in the same habitat, which is indeed the case at this location.

Here are some key points to distinguish the two species:

Bracts at the base of the umbel:

D. carota has a dense ring of branched bracts

Perideridia has one or two short, simple bracts, sometimes none.

Leaves:

D. carota: when flowering it has green, lacy, fern-like leaves. It also has dense basal leaves.

Perideridia: when flowering it has withered (often brown) leaves with only a few branches. Their compound leaves are made of long, thin segments. Its lower leaves are dead and shriveled and there are no basal leaves.

Stems:

D. carota has short bristles

Perideridia has bare stems

Seeds:

When D. carota has gone to seed, the umbel closes and it has seeds with burrs, which readily attach to socks or fleece clothing.

Perideridia umbels stay open and the seeds don't have burrs.

Odor:

D. carota smells like carrots. It's the ancestor of the cultivated vegetable.

The odor of Perideridia is hard to describe but it's delightful and you need to experience it. It's like a combination of citrus, celery and cinnamon. The fruits while green (which are two-seeded structures) are the most potent but any part of the plant at any time has a similar odor.

I'm pretty sure the species in the photos here are Gairdner's Yampah (Perideridia gairdneri) but I'm not certain. P. oregana does occur in the Willamette Valley but is less common. P. gairdneri is quite variable. It tends to have fruits that are wider than long where P. oregana is supposed to have fruits that are longer than wide. First, I'm not showing ripe fruits here and this may not be the most reliable way to tell. Other features may require expert review of multiple aspects of the plant which I did not sample.

According to Oregon Flora:

Perideridia gairdneri is the most widespread and variable species of the genus in our flora. Morphologically, the species greatly resembles both P. erythrorhiza and P. oregana. It differs chiefly from those species by only the color of its roots (P. erythrorhiza) and the development of its involucel bractlets and chromosome numbers (P. oregana). Given the similarities of the three species, study of their potential conspecificity may be warranted. Populations of P. gairdneri on the California coast with branched stems have been described as P. g. ssp. gairdneri. If this taxon is recognized, our plants would be P. g. ssp. borealis.

Don Boucher

NE Corvallis