Crab Grass

Asked February 27, 2020, 6:08 PM EST

Large problem with crabgrass last year despite applying a pre-emergent and also a spray on later. I live in Prineville and I am wondering for this year (2020) with the impending early spring, when would be the best to apply the granular. If I need the soil temp up to 50-55 degrees, at what depth would I need to measure that?

Crook County Oregon

1 Response

HI, I would think just a couple of inches deep in the soil would be the best. I am attaching a link to a presentation on crab grass, bermuda grass, and nutsedge that you might find interesting. Crab grass is an annual and is growing from seed every year.

https://extension.oregonstate.edu/sites/default/files/documents/1/mglawns.pdf

Following are some more resources:

https://pnwhandbooks.org/weed/horticultural/turfgrasses/annual-grass-weed-control-turf

“Crabgrass” (University of California) http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7456.html -

“Maintaining a Healthy Lawn” http://ir.library.oregonstate.edu/xmlui/bitstream/handle/1957/19232/ec1521.pdf

Hope these resources are helpful.

Mylen Bohle
Area Extension Agronomist
CEntral Oregon
OSU Crook County Exnteison Service
498 SE Lynn Blvd.
Prineivlle, OR 97754
541-447-6228
mylen.bohle@oregonstate.edu