Lesser Celandine (Ranunculus ficaria) on Mar 18, 2018
Submitter does not have a specimen
EDRR Status: Local expert notified
Description of specimen
Location one: 150th & Divison plants are spread in random throughout approx 50ft x 100ft lot.
Location two: 160th & Divison City trail Park plants are surrounding water pump house and additional plants in larger clusters are across the trail in city’s grass field adjacent to neighboring homes approx 100ft from Scheupbach Facility
Thanks for reporting this! Yes, it looks like lesser celandine. I've seen it in bloom in other locations as well. It's a hard plant to control. Included below is a useful link to a lesser celandine fact sheet from 4-County CWMA.
https://4ccwma.files.wordpress.com/2018/02/ipm_18_lessercelandine-web.pdf
Manual hand pulling is generally not recommended in riparian zones and wetlands unless dealing with an extremely small infestation (i.e., a few plants). Soil disturbance can increase its spread. There are some recommendations in the fact sheet for herbicide application. Since plants have already bloomed, it may be too late to spray, but you could still try. Rodeo (glyphosate) has an aquatic label and can be applied near water. You should always read the label in regards to determining the spray rate and where you can and cannot spray. It's best to control infestations early on before they spread. Once celandine gets established, it's difficult to eradicate.
I believe the park you are referring to is on Tualatin Hills Parks and Rec District property (if it's Scheupbach Park). I will notify the person in charge there.
If you have any other questions, please let me know. Thanks!
Kind regards,
Tyler
Tyler Pedersen
March 19, 2018, 2:15 a.m.