Yarrow in the Grass
Is there a way to remove yarrow from our lawn? It is spreading like crazy. It's green, we mow it, but we think it might like to take over.
Larimer County Colorado noxious weeds
Yes, yarrow can be one of the most difficult weeds to control in the lawn and will take several applications of herbicides to remove it. If you do not want to use herbicides, you can try digging it out, going a few inches beyond where it's currently growing and at least 4-6" deep.
However, if you would like to try herbicides, a combination product will work well. Both Ortho Weed Be Gone Max Plus Crabgrass Control or Bayer Advanced Lawn Weed and Crabgrass control will work on yarrow, but it will take several applications (product should be labeled for yarrow). Read the label carefully and apply according to the directions; repeat the application when allowed (usually 10-14 days apart). Spray on a clear, calm day with no wind. If you're going to spray the product near any solanaceous crops (tomatoes, peppers, eggplant), take extra caution, as these crops are very sensitive to the chemicals (especially quinclorac) in these products. Note that these chemicals are only approved for use in the lawn...not in garden beds.
I also had yarrow in my lawn and used one of the above products--it took a couple seasons, but I was able to get rid of it. Also focus on good cultural practices for your lawn--regular water and fertilizer will help the turf out-compete the yarrow. You can also try mowing your lawn a little higher, as yarrow doesn't do well with shade.