Land Plants - non-native

Black Locust (Robinia pseudoacacia) on Feb 18, 2011

Submitter has sample
EDRR Status: Population assessed

Description of specimen

Photographs from 10-14-2009 of a very young (first season) seedling Robinia pseudoacacia, which I dug and photographed again to verify its seedling status. Had the seedling been left to grow, it would have been underwater close to half of the year.

I believe that our dry summer soils keep this from seeding about in drier settings. This seedling was close enough to summer water levels to be watered by the Clackamas.


Has anyone verified seedlings in dry upland areas? I have seen only what appear to be root sprouts at upland sites, and this is the only definitive seedling I have observed.

Feb. 18, 2011, 9:07 p.m.

Dear Mr. Boyce,

Thank you for your report of Black locust. While black locust is not a species that we are not actively controlling at this time, sightings such as this are very useful to us in evaluating what species and infestations to target for our rapid response program. Your report will us to reevaluate our local priorities to maximize the benefit to Clackamas County. So thanks again for taking the time to report this species. All the best,


Samuel Leininger
WeedWise Program Manager
Clackamas Soil & Water Conservation District
221 Molalla Ave. Suite 102
Oregon City, OR 97045

Samuel Leininger
March 1, 2011, 5:23 p.m.