Having trouble identifying a weed - Ask Extension
A strange bunch grass has appeared in my garlic field. It has three tuber like nodules at the base and is deeply rooted. At first I thought is was w...
Knowledgebase
Having trouble identifying a weed #747987
Asked May 04, 2021, 3:17 PM EDT
A strange bunch grass has appeared in my garlic field. It has three tuber like nodules at the base and is deeply rooted. At first I thought is was wild onion grass, but am not so sure. When I cut the nodules, they have no onion or garlic smell. See attached pictures
Linn County Oregon
Expert Response
Thank you for reaching out to OSU Extension Service. This weedy species is a new one for me. I forwarded your photos on to the curator at the OSU Herbarium and he reported back that it looks to be the bulbous form of Tall Oatgrass (Arrhenatherum
elatius ssp. bulbosum). It is an introduced species that can be invasive in cultivated agricultural fields because the bulbous corms at the base can break off and vegetatively grow new plants.
Mechanical control will require somehow removing the corms. Pulling or digging could be options. For effective herbicide treatments we can provide this recommendation: https://pnwhandbooks.org/weed/problem-weeds/oatgrass-tuber-arrhenatherum-elatius-var-bulbosum
elatius ssp. bulbosum). It is an introduced species that can be invasive in cultivated agricultural fields because the bulbous corms at the base can break off and vegetatively grow new plants.
Mechanical control will require somehow removing the corms. Pulling or digging could be options. For effective herbicide treatments we can provide this recommendation: https://pnwhandbooks.org/weed/problem-weeds/oatgrass-tuber-arrhenatherum-elatius-var-bulbosum
If you would like to see a sample, I can provide one. I am in the process of digging the rest out of my garlic field in a couple days, so if you want a sample, let me know before I get rid of all this weed.
Stephen Leight
SD Farm
Stephen,
I hope that the digging went well! I was on a farm this morning and spotted a few plants of the bulbous oatgrass. Now that I know what I'm looking for I'll probably start seeing it in many places. I appreciate the opportunity to learn and am hopeful this weed won't be a continued issue for you and your garlic production.
Sincerely,
Melissa Fery
I hope that the digging went well! I was on a farm this morning and spotted a few plants of the bulbous oatgrass. Now that I know what I'm looking for I'll probably start seeing it in many places. I appreciate the opportunity to learn and am hopeful this weed won't be a continued issue for you and your garlic production.
Sincerely,
Melissa Fery
