Help with Grass/Weed ID

Question: Hi...I live in Middletown and this spring I have noticed this weed/grass slowly taking over my yard. I have tried to ID it and I am not sure if it is POA Pratensis or POA Trivialis.   As you can see in one of the photos it does have a purple tint to the grass stalk.  If you ID it can you tell when what herbicide would work best to get rid of it?

Any assistance you can provide would be greatly appreciated.  

Thanks again,

Pat

responder: John Emerson Jr.University of DelawareTurfgrass Nutrient Management Extension AgentEmail: jremer@udel.edu Replied April 02, 2024, 7:30 PM EDT
response: Hi, This is Poa trivialis or Roughstalk Bluegrass. Unfortunately, the only chemical control options are glyphosate. You will need to reestablish seed or sod wherever you apply the glyphosate. Roughstalk bluegrass tends to proliferate in wet, poorly drained areas as well as when excessive irrigation is applied.

responder: The Question Asker Replied April 03, 2024, 9:59 AM EDT
response: John,Thanks for getting back to me so quickly.  I appreciate all the help. Do you think the excessive rain we have had this spring in Delaware could be contributing to the amount of POA Triv I could be seeing in my yard?  I haven’t even turned on my irrigation yet and most of the areas I see it have decent drainage.  I didn’t overseed last year so it’s not a contaminated seed issue.   This is the first year I have seen it and it’s super prevalent and taking over a bunch of my yard.  Thanks for the help.  Pat On Apr 2, 2024 at 7:30 PM, <Ask Extension> wrote:

responder: John Emerson Jr.University of DelawareTurfgrass Nutrient Management Extension AgentEmail: jremer@udel.edu Replied April 03, 2024, 12:50 PM EDT
response: The rain could've contributed to the increased size I suppose, but it has had to have been there for some time. Chronic overirrigating can cause seeds to germinate that may be in the seed bank and then a wet spring favored their proliferation. Going forward, I recommend only irrigating when there are visible drought stress symptoms. Avoid irrigating on a set schedule. Normally we don't need irrigation to turf until late May or even June.

responder: The Question Asker Replied April 03, 2024, 1:06 PM EDT
response: John,Thanks so much.  Last question. Does Poa Triv die off in the heat like Poa Annua or is it around all summer long ?Thanks againPat On Apr 3, 2024 at 12:50 PM, <Ask Extension> wrote:

responder: John Emerson Jr.University of DelawareTurfgrass Nutrient Management Extension AgentEmail: jremer@udel.edu Replied April 03, 2024, 2:43 PM EDT
response: It does not die off during the summer, but it may seem that way. It will turn brown and be quite an eye sore, but it will come back and turn green again once the summer heat breaks in the fall.

responder: The Question Asker Replied April 04, 2024, 3:16 PM EDT
response: Hi John,I was able to go out into the yard and pull some of this up.  It comes up super easy.  Is it possible that this could actually be Annual Ryegrass as opposed to Poa Triv? I noticed the base of the stalk is purple.  I just wanted to confirm before I try and kill it off.  Pictures are attached.  Thanks againPatOn Apr 3, 2024 at 2:43 PM, <Ask Extension> wrote:

responder: John Emerson Jr.University of DelawareTurfgrass Nutrient Management Extension AgentEmail: jremer@udel.edu Replied April 05, 2024, 9:30 AM EDT
response: It definitely is Poa trivialis.

responder: The Question Asker Replied April 05, 2024, 10:01 AM EDT
response: Thanks again for your help.  On Apr 5, 2024 at 9:30 AM, <Ask Extension> wrote: