Noxious Weed Control on CREP Contracts
Your CREP contract also includes the requirement that you perform weed abatement on enrolled acreage. Noxious weed control isn’t just limited to CREP participants, however. Anybody who owns or operates farm ground or pasture has a vested interest in weed abatement.
Weed abatement is not as simple as just “spraying something” to kill them. Weeds are classified as “noxious” for a variety of reasons. One reason they may be so classified lies in the fact that some are very difficult to kill. For that reason you will need to have a plan of attack, and be diligent about continuing your efforts.
Many plants officially designated as “noxious weeds” have quite pretty flowers. In fact, a lot of today’s noxious weeds were yesterday’s landscaping plants! They may be pretty in bloom while there are just a few of them, but when they’ve rendered useless 40 acres of your pasture you are going to want somebody to do something. By law, YOU are that “somebody” and NOW is the time to do something.
So how are you supposed to suddenly become an expert on noxious weed abatement?
Help is available. Noxious weed abatement is BIG business in the West these days, and it’s only going to get bigger. Government agencies as well as private corporations continually are working to improve the technology available to you, the landowner. Better, more selective chemical herbicides are being developed all the time. Biological control methods undergo continual testing. Local governments annually seek funds to assist both private and public landowners with their weed abatement needs. Oregon State University Extension Service annually updates the Pacific Northwest Weed Management Handbook, which is available online or can be purchased for your ready reference – more about that later.
The State of
By far the most common noxious weed you likely will have to deal with is the Canada thistle, which thrives in both wet and dry locations. Some parts of the south county will find perennial pepperweed to be their biggest problem, but virtually everybody has Canada thistle. Canada thistle is a very difficult plant to kill, because of the way it grows and the way it reproduces.
Many people have applied herbicides to a patch of Canada thistle, only to return the next day to find the entire patch looks dead. That is a survival mechanism this plant uses, and it works very well. Most folks, upon finding the “dead” patch, would consider they had made a very successful herbicide application, and wouldn’t give another thought to that particular patch of thistle.
Systemic herbicides work by being absorbed through the leaves and translocated into the root system. When Canada thistle starts to absorb herbicides, the root system actually has the ability to pinch off the above-ground stem to which the herbicide was applied. This results in the stem itself dying, but very little, if any, of the chemical actually gets into the root system. Consequently the plant simply sends up a new crop of above-ground stems, and continues growing unimpeded by the herbicide application. The key to successful control of Canada thistle is to make repeated applications to the new stems until the root system no longer has enough stored energy to send up any more shoots. (Always follow label directions; they’re there for a reason!)
What makes this even more difficult is the fact that Canada thistle plants spread underground. A single plant may cover a very large area, so it is imperative that you spray-to-wet every single stem and leaf you can find! It may take 4 or more herbicide applications, repeated at 2-3 week intervals, to finally get ahead of the plant. But you can expect it to return the next year, because it also reproduces by seed, so don’t give up and don’t get discouraged! The objective is to keep it under control, not to expect to eradicate it. However, it will get cheaper and easier to maintain control as time passes, once you initially get control of the problem.
As noted above, Canada thistle is not the only weed you’ll face. Each year the County designates noxious weeds as “A”, “B”, or “C” weeds. Category “A” weeds you absolutely must kill. “B” and “C” weeds are the ones you will generally encounter, and you want to kill them for your own economic well-being; Canada thistle is a “B” weed for 2006. Required abatement of “B” weeds is determined on a case-by-case basis, so you don’t want to let it get the upper hand, or the County may be obligated to take some kind of action.
Other useful resources include the aforementioned Pacific Northwest Weed Management Handbook. This 440+ page book is available online at http://ag.ippc.orst.edu/pnw/weeds
You may order a hardcopy from OSU by email at puborders@oregonstate.edu/catalog
If you prefer, you can call them toll-free at
1-800-561-6719, or mail in your order by writing to: Publication Orders,
Extension & Station Communications,
You also have a number of advisors at your disposal. Contact the County weed abatement office at (541) 883-4696, the OSU Extension office at (541) 883-7131, the Oregon Department of Agriculture Noxious Weed Control Program at (503) 986-4621, or the Soil and Water Conservation District at (541) 883-6932 for more information. Any of those entities will be happy to assist you in any way possible.
If you’ll pardon the pun, noxious weeds are a growing problem. You can do your part to solve that problem, and reward yourself with a healthier pasture and riparian corridor at the same time.
Closeup of newly emergent Canada thistle.