When you ask any farmer about raising top yielding crops, chances are you’ll hear about the fertility that goes into feeding that crop. What gets left out in many cases is weed control. I’ll be talking about various annual weeds in the Blank Slate field as the season progresses. Today I want to focus on a tough perennial weed that is my number one concern going into 2011.
There are a number of names farmers call this weed that I can’t mention. I call it “Scouring Rush” and that seems to be the most common name for the weed. The reason farmers hate it so much is that it’s very difficult to kill. Normally scouring rush is worst on years where rainfall is plentiful. I have it on the Blank Slate in the lower ground, and my neighbors down hill from me have it just as bad. Scouring rush has rhizomes which are below ground runners. With the rhizomes, the weed patch grows and grows each year even if you burn off all the above ground portions of the plant.
The tough thing about scouring rush is that it really doesn’t have leaves or hairs or anything to stick herbicide to. Also the stems are erect, so any droplets that do land on the plant while spraying are likely to just run down the plant and end up on the ground. My favorite herbicides to control it are Gramoxone and Ignite. Both are non-selective herbicides, which mean they kill all weeds. Ignite is selective only in Liberty Link crops. Unfortunately for me, I wasn’t able to get the hybrid I wanted for this farm with a Liberty Link trait (which allows the safe application of Ignite herbicide when the crop is emerged).
My hybrid is tolerant to Roundup, though, so that will be the first option. To have any chance of it working, you must spray a very concentrated (low water volume) application. This way if even a few droplets stick to the plant, you have quite a bit of herbicide there to do the job. Adding some sort of sticker to the solution is a good idea as well. IF, and that’s a big if, you actually got Roundup into the plant it would give you the best chance at completely killing the weed roots and all.
I’m planning that this will not work, so I’ll likely spray some Gramoxone or Ignite on the scouring rush sometime between now and planting time to try to knock out the scouring rush. These two products will just provide topgrowth control, so I’ll likely be at it for a few years to completely solve the problem.