When confronted with lawn weeds, typically we think of dandelion, creeping Charlie, and violet. These aforementioned plants and many others are classified as broadleaved weeds (dicots), and are easily distinguished from grasses (monocots). Scientists are able to engineer herbicides that target broadleaved plants, while the chemical remains benign to desirable turfgrass.
But what happens when you have a grassy weed appear in your lawn? Selective lawn herbicides containing 2, 4-D or dicamba, useful in controlling broadleaves, will not work on grasses. And it seems grassy weeds are being found more commonly in home lawns.
Annual grasses, such as crabgrass are best controlled with a preemergent herbicide applied prior to the offending weeds germination. If the crabgrass seed has germinated a homeowner should practice good lawn care culture (keep reading for those) and a post-emergent herbicide application.
Perennial grassy weeds like quackgrass or nimblewill have become big problems in recent seasons. They are difficult to control because they are, well…perennial, meaning they come back year after year and for the cool season grassy weeds, they match the lifecycle of our desirable cool season turfgrass species. Often homeowners must resort to spraying a non-selective herbicide (i.e. glyphosate), rake out the dead patch and reseed with their desired species of turf.
Other products can be used, but those are best left to professionals. And most can only legally be used by licensed applicators.
In my yard, I do not spray herbicides on my lawn. Good lawn culture gets me about 80% of the way to a perfect lawn. The other 20% is easy to live with. Everyone has their own definition, but to me a successful lawn is a groundcover that won't erode and send sediment in our waterways and that tolerates my family's activities. The benefit of weeds is that they are still green; the added benefit of weedy grasses is that at least they blend in (more or less) with the turf.
If I had to boil it all down to a quick and dirty list of proper lawn care practices, it would include the following:
- Mow high – I set my blade to the highest setting (3-inches). Cool season grasses are more adapted to this height.
- Sharp blades – Getting a mower's blades sharpened can make a world of difference.
- Avoid high amounts of nitrogen early in the spring. I prefer to feed my lawn in the late summer to early fall.
- I overseed in late summer to early fall.
- Keep it clean. Meaning I pick up after my dog and shred fall leaves back into the lawn or for garden beds.
- Stay on top of mowing. Yes like everyone, the lawn gets away from me, but when schedules are tight and rain is approaching I try very hard to squeeze in some mowing here and there. Avoid removing more the 1/3 of the leaf blade so as to not stress the lawn.
If you are thirsty for information about lawn care check out our website LawnTalk.