Spraying for pasture weed control

We’ve been spraying a good bit this summer. I have been concentrating on a neighbor’s property I farm for a few years and have to catch up on mine, so I’ve been thinking a good bit about spraying. The thing that specifically prompted this item was a conversation with a man who lives a few miles from here.

Roger pointed up to some troublesome pasture across from his place. “It has to be brush hogged every year,” he said. After talking a little bit, we agreed that “Brush hogging is about the same as putting fertilizer on the bushes.” I said what was needed was to spot spray the brush. Roger thought that would do no good , either. This is common idea, but very wrong.

The trick to spraying is to get it right. You have to get the entire foliage wet with properly formulated spray. A lot of people think spraying is not good work. They want to sweat when they work, I guess. Spraying is not big muscle, broad stroke work, it is control and thought work. You have to hit the bush, not just spray toward it, and if it is large or dense, you have to get the other side. too. I want to characterize spraying for effective control of woody plants and some other large pasture weeds.

First of all, you want to decide what you want to kill. Certainly that will include multiflora rose and autumn olive (and the very similar, thorny, slightly harder to kill, tartarian honeysuckle). You will want to vigorously control invasive species, like the new thistles that have come in from the west and tree-of-heaven. But do you want to waste spray on sand brier and the common thistle or other weeds than be controlled by application of lime? Or the many species that can be controlled by mowing at the right time? Each species requires a decision.

Once you have some idea of what you want to control you must decide on the spray. Talk to other people. The Extension Agent, your feed store manager and farmers in the neighborhood can give advice on effectiveness. It is best to use the least amount of spray recommended on the label early in the season. You can begin spraying as soon as the leaves are out in the spring. The concentration given is intended when the spray covers one side of the leaves, you don’t have to drown them, just get 85-90% of the surface. What drops off is wasted. Normally some will miss the target plant. It has little effect on grass, but is hard on legumes.

The least concentration is required in the early season when there is more water and growth is lush. As the season progresses the plants become slightly more resistant and you can move up the range suggested on the label. If you don’t, the kill will become less effective. If it is a rainy time use less, if dry move up to the suggested maximum.

Twisting the outermost part of the nozzle adjusts the diameter of the spray stream. I like to have it spread out to about a foot to eighteen inches at 20 feet from the nozzle. That's too small for close work, and it has to be moved around for large brush at a distance, but seems to be a good compromise.

Do your cleanest field first! These will normally be nearest the house or your starting point. Little plants take little spray, so you are effectively cleaning up more ground by doing the best first. You will be going over this ground later to go further from the house. You can clean up on successive trips a couple of weeks or more later when you can see what you have missed.

All your ground should be gone over each year, if possible. Keeping the “filth,” as folks used to call it, in check, is much easier and cheaper if the weeds never get large. You will find if you clean up an area, including around the edges, that it only “goes back to the Indians” very slowly. Getting the pH up is very helpful, too, because it makes the weeds work a lot harder to get established in thick grass. Also, avoid over grazing, which lets many weed get a start.

The following item on this blog illustrates a spray apparatus that has worked very well for me. At one time I used a tractor mounted sprayer, but as I got older getting on and off became the largest part of the spraying job. The tank behind a four wheeler allows you to sit most of the time but you can easily get off when needed. You can get over a lot of ground when the weed plants are far apart. Having a hand sprayer helps with places too steep or otherwise inaccessible. We still maintain a tractor sprayer for places that require large volumes, such as clearing out along a forest edge, or along a fence line that requires walking some distance and using large volumes of spray. (HINT: You can make your own tractor mounted sprayer for about half the cost of a similar one that comes from a dealer.)

Read the following article for ideas about use of a four wheeler.