This is the first of several bush-mallow challenges I’ll be posting for this project. If you live in the Ukiah area or want to go on an adventure, here is some information to help you possibly find this species. Any observations of any bush-mallows from this area would be very useful information.

According to the California Native Plant Society, Mendocino bush-mallow (Malacothamnus mendocinensis) is confirmed from only two historic collections near Ukiah, CA, the last in 1939. It is currently presumed extinct, but bush-mallows are mostly fire-followers and there have been no fires near the type locality for a long time. There are some recent burns relatively nearby which may be worth searching though. The best time to find it in flower would likely be May through July based on the few existing specimens.

Below is a map (larger version here) which shows the presumed localities as a star and an asterisk. The red areas are recent burns and the best likely locations to search for the plants. Follow this link for an interactive fire map.

Below is a scan of one of the type specimens (larger version here).

This crop shows the “conspicuously angulate and striate stem” which is one of the key distinguishing features of this species.

See also my post here on what to focus on if you want to be able to ID a bush-mallow from photos.

The second challenge is to find some living plants near the type locality of horehound bush-mallow (Malacothamnus marrubioides). If you live in the Friant area or want to go on an adventure, here is some information to help you possibly find this species. Any observations of any bush-mallows from this area would be very useful information as the nearest other bush-mallow observations are over 30 miles away. All other specimens that are currently called horehound bush-mallow are over 100 miles away. Being that disjunct makes me wonder if they actually are the same taxon.

The type locality of horehound bush-mallow is supposedly from Fort Miller which is now under Lake Millerton. It appears that a single specimen was collected and a few other specimens have been made of fragments of this specimen. The expedition this was collected on stopped at Fort Miller for a week at the end of July in 1853. I could find little detail about that week, but I suspect the specimen may just be from the general area of the fort and that they likely went exploring. The elevation of the fort is a bit low for at least one of the species that was attributed to there. Here is the exploration record if interested. It’s pretty cool.

Below is a map (larger version here) which shows the presumed locality as a star. The red areas are recent burns and the best likely locations to search for the plants. Follow this link for an interactive fire map.

Below is a scan of the type specimen (larger version here).

This illustration is from the published account of the expedition. Larger version here.

Here are some photos of what are considered horehound bush-mallow north of the Los Angeles area.

See also my post here on what to focus on if you want to be able to ID a bush-mallow from photos.