New grass/weed invader - Ask Extension
I am in year #3 of growing a buffalo grass back yard. You folks have been extremely helpful in advising me with purslane and yellow foxtail problems...
Knowledgebase
New grass/weed invader #864624
Asked April 15, 2024, 3:19 PM EDT
I am in year #3 of growing a buffalo grass back yard. You folks have been extremely helpful in advising me with purslane and yellow foxtail problems of prior years. And I have another problem I need to identify and resolve. It is a fairly robust grass or weed. (Pictures attached). Can you tell me what this is? Is there a commercial herbicide that can be used without killing the buffalo grass?
Best,
Scott Moore
FortCollins
Larimer County Colorado
Expert Response
Hi Scott,
This is tall fescue and was probably in the lawn before you planted the buffalograss. It's pretty persistent and resilient and has deep roots.
So it's a "lawn grass" and you'll need to use a non-selective herbicide to remove it. We don't have any selective products that will take out the tall fescue from your buffalograss.
You're in a bit of tricky window, but you can use glyphosate (Roundup, Kleenup) now, but be very careful - only spray the clumps of grass and not the buffalograss. Spray on a calm day when temperatures will be above 75 for a few days (obviously not anytime soon). You can also take the glyphosate and wipe it on the grass using a towel or paintbrush.
It will probably take 2-3 applications to kill the tall fescue entirely, applied 10-14 days apart. The buffalograss isn't likely completely dormant - if you look closely, you'll probably see some green at the roots - so just be very careful about overspray.
Only use a product with glyphosate - none of the "365" or "Season Long" controls.
This is tall fescue and was probably in the lawn before you planted the buffalograss. It's pretty persistent and resilient and has deep roots.
So it's a "lawn grass" and you'll need to use a non-selective herbicide to remove it. We don't have any selective products that will take out the tall fescue from your buffalograss.
You're in a bit of tricky window, but you can use glyphosate (Roundup, Kleenup) now, but be very careful - only spray the clumps of grass and not the buffalograss. Spray on a calm day when temperatures will be above 75 for a few days (obviously not anytime soon). You can also take the glyphosate and wipe it on the grass using a towel or paintbrush.
It will probably take 2-3 applications to kill the tall fescue entirely, applied 10-14 days apart. The buffalograss isn't likely completely dormant - if you look closely, you'll probably see some green at the roots - so just be very careful about overspray.
Only use a product with glyphosate - none of the "365" or "Season Long" controls.
