Bermuda Grass and Japanese Stiltgrass
This stuff is just awful. If you have it, you know it and you want to pull your hair out. Personally, I have the bermuda grass, aka ........, at my community garden plot and japanese stiltgrass at home ~~ just like everyone else in my neighborhood! Very limited resources are able to get this stuff if you want to live the organic life.
Biologically speaking, it should be easier to get rid of the japanese stiltgrass (Microstegium vimineum) because of how it grows. It was introduced into the United States in Tennessee around 1919 and likely escaped as a result of its use as a packing material for porcelain. Because it is shallow-rooted, stiltgrass may be pulled by hand at any time ~ I feel very satisfied when I pull this stuff! If flowering, cut plants back using a mower, weed whip or other device to prevent seed production - especially in late summer when the seeds mature.http://www.nps.gov/plants/alien/pubs/midatlantic/mivi.htm The big problem with this grass is that it is so invasive, it will eventually choke out native plants as well as the nice grass you actually want to grow in your yard!
This past spring, I had finally reached my limit with this stuff in my yard. I asked a professional at Merrifield Garden Center what to use. I asked if corn gluten meal, an organic pre-emergent product, would work. I also asked about Preen, a chemical treatment for crabgrass removal. I eventually settled on another product which also treats the japanese stiltgrass. It also has corn gluten as the No. 1 ingredient on the item list.
In mid-March, I applied it on a part of my yard which has been taken over by the weed as you should use this pre-emergent around the time the forsythia bloom. As of today, it has done a marvelous job controlling the stiltgrass! The only problem now is the edges of the parcel of land because I could not reach everywhere ~ how frustrating! It is also in a lot of my planting beds. Easily removed but still annoying.
Now, on to the Bermudagrass or Wire Grass (Cynodon dactylon). Ugh. This stuff can root at every leaf node, it can tunnel underground from any leaf blade to create a new "branch" to sprout in another direction. The vines can become matted both on top and below the soil surface. It can grow up to 6-9" below the surface and become nearly impossible to eradicate. C. dactylon reproduces through seeds, through runners and rhizomes. Growth begins at temperatures above 15 °C (59 °F) with optimum growth between 24 to 37 °C (75 to 99 °F); in winter the grass becomes dormant and turns brown. This does NOT mean the grass is dead!! http://www.ppws.vt.edu/scott/weed_id/cynda.htm
I am a gardener at one of the Reston Association organic gardens. This is awesome in many respects - you can eat the veggies right in the garden, you don't have to worry about overspray from someone's pesticide, etc. The one thing we cannot do is spray Roundup to get rid of this grass. We could spray vinegar but this will only take care of burning/killing the surface vines; you would still have to dig the roots out by hand. Again, I say - UGH.
I always feel good when I fill trash bags each spring with this nasty stuff. I only feel good until my hands and elbows start to hurt from all the pulling and digging! I have found a fantastic tool to aid in the removal of this witch grass - a Korean Hoe or Hand Plow. This marvelous tool can be found at the Grand Mart on Rt. 7 during certain times of the year, not sure if they still have them now that it is June. If you can find one, BUY IT! This is just an awesome garden tool!
But, this fast-growing grass is a tedious herbaceous pest and you need to keep on top of it throughout the entire year as it never seems to get cold enough to kill it off. It will grow under planter boxes, under weed cover, under and over plastic, just about anywhere...all year. Once infected, be diligent because it takes over.