Turf Grass Weeds
For the past two years I have battled chickweed in my turf grass. I was able to knock it down in the Spring but it comes back in the fall/winter. This Fall (2015) as each year I overseed, feed and lime my lawn. I did not kill the chickweed before doing this. That was about 8+ weeks ago and while the seed grew and I mowed 2 times before the end of the growing season the chickweed is plentiful and doing well. Can I now put down an herbicide to kill those weeds without harming the new grass and if so which would you recommend. I want the new grass to get the nutrients and not the weeds. I have attached a photo of what is representative of the entire lawn.
Anne Arundel County Maryland
Please take a look at this page from our website: http://www.extension.umd.edu/hgic/lawns/lawn-weed-identification
Having a good turf lawn is a multi-pronged approach which includes good management and best practices. For weed control, it's good to know their life-cycle. Click on the chickweed photo.
As you will see, chickweed is a winter annual, meaning it actually germinates in late summer/early fall...and in years like this where it has stayed wet and relatively warm, it can continue. You're grass looks pretty good though.
Depending on size, you could hand-pull, or use an herbicide containing triclopyr. (Click on the link to broadleaf weed control).
Early next fall, you could use a pre-emergent weed control to prevent germination of a new crop.