justing.net

Hayfield Tarweed

By Justin G. on 24AUG03SAT

So, I’ve been lamenting that there is a large patch of stinkwort (also wikipedia) up the hill from the area that we had just spent the last two summers clearing of that invasive weed. But, it turns out that I was wrong; it is hayfield tarweed, specifically the hemizonia congesta ssp.¹ congesta variety, a native plant. I think my mistake was that these two plants are a little harder to distinguish when juvenile.

So after sorting that out, and being quite relieved, but not too relieved because there is still a lot of stinkwort further up the hill across the canal, my curiosity was piqued about this tarweed in general. What is it? Where does it grow? Does it have any uses? Anything else special about it?

What it is

The specimens that I am seeing are 2-3 feet tall (up to 1 meter, ish) and have small white flowers (1/2 inch or about 1 cm). The rest of the plant is a dusty green with slender leaves relatively sparsely distributed throughout. It is found in the SF Bay Area region, the Calflora link above and CalScape both list a range that basically overlap with the population and may be derived from the same data set, I don’t know. There is quite a lot of it around my local part of the Santa Teresa Hills, so I’m kind of curious how common it is here in the range; it is listed as endangered. Based on this Calflora observation search page, it appears that there is an opportunity to contribute some missing observations to the database. It appears that I can create an account and contribute directly to Calflora. I suppose it’s that or iNaturalist.

Uses

So, what can we do it? Err, I mean, what have people done with it? I’m not planning to do anything with it, I’m just curious. It was kind of hard to find anything at first, but this nursery page mentioned the seeds from tarweed are used in something called pinole (pin-o-lay). Searching for that kept directing to the town of Pinole which is in the SFBA, so that seemed relevant. It turns out that the town is named for some foodstuff that the Ohlone gave to the Spanish, so the Spaniards named the village area that.² What in the heck is pinole? The rather generic description on the wikipedia page left too much to the imagination, it could be anything! Just searching for pinole brought up this recipe for basically native American energy bars. That’s something that I could see myself making, actually.

There may be other uses and more obscure info about tarweed, but at least for now my curiosity is satisfied.

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