By David Hart
There’s a monster out there — a green menace lurking in your food plot. It’s not a plague of insects or some alien disease. No, this monster is that catch-all category of plants we call “weeds.” Fescue, Bermuda and other grasses, along with curly dock, thistle and countless other varieties of broad-leaf plants, are unwanted visitors in any food plot.
So what’s wrong with weeds? Plenty. They rob clover, alfalfa, beans and wheat of vital nutrition, moisture and sunlight. Weeds can turn a healthy food plot into a marginal one; and that, in turn, can lead to plants that offer less nutrition to deer. They rob your plot of root space, as well, turning an acre of deer food into a patchwork of weeds and grasses with a little clover or wheat in between. Uncontrolled weeds create an endless cycle of planting and replanting and can eliminate a season’s worth of effort in just a few short weeks.
Mark Trudeau, national sales manager for the Whitetail Institute and a retired farmer from Alabama, said allowing weeds to grow in a food plot is no different than letting a flock of pigeons feed in your chicken coop. It’s a simple matter of competition.
“Your chickens will either be less healthy because they won’t be getting enough food, or you’ll have to give them more food in order to make up for what the pigeons are taking,” he said. “For plants, food is fertilizer, and we all know how expensive fertilizer is these days. Anything you can do to cut down on unnecessary expenses is a good thing, and controlling weeds is a great way to have strong, vibrant food plots without spending a whole lot of extra money on fertilizer.”
The Right One
In most situations, controlling weeds means giving them a dose of herbicide. A variety of chemicals is available, and each one has a specific use. Some, like Whitetail Institute’s Arrest, kill grasses like fescue, Bermuda and Johnson. Grass-specific herbicides also are available under the brand names Poast, Vantage, Ornamec and Grass-B-Gon. Those products will, however, also kill rice, corn and wheat (all members of the grass family) so make sure you read the label before spraying.
Broadleaf herbicides are used to remove unwanted plant growth in grass-type food plots like wheat and corn. One of the most common is 2, 4-D, used most often to control clover on lawns and golf courses.
Whitetail Institute’s Slay is a broadleaf herbicide that doesn’t kill clover or alfalfa. Both plants are in the legume family, and the active ingredient in Slay won’t harm either. However, it won’t kill grass, so if your clover has a grass problem, you’ll need an application of a grass-specific herbicide.
Spraying herbicides at the right time is the best way to keep weeds out of your food plots.
“If I could only use one type of herbicide, I would probably use one that controls grass,” noted Trudeau. “Broad-leafs plants can create a lot of headaches in food plots, but grasses like fescue can be much worse. They don’t provide any benefit to wildlife, while some broad-leaf weeds act as a food source for deer and other wildlife.”
Grasses are such a problem that some seed makers are producing food plot mixes designed specifically to overcome grass intrusion. “A lot of people don’t have the time, money or know-how to battle weeds,” said John Carpenter, national forage and wildlife products manager for Pennington Seed Co. “Why not plant a seed or seed combination that is more durable and fights weed pressure? Rackmaster Durana and Buckmasters Ultimate both will compete aggressively with weeds and require less chemical applications — for that matter, less maintenance altogether.” Carpenter explained that the Durana clover in the Pennington mixes puts out more runners and is able to survive weed intrusion and even choke out weeds.
But there are certainly many times when a good dose of weed-killer is called for. Glysophate, the active ingredient in Roundup, is a non-selective herbicide that will kill all plants it contacts. There are countless generic brands sold at farm and home supply stores everywhere, often for a fraction of the cost of the most popular brands. They all work the same, although cheaper brands often have a lower amount of active ingredients in the same-size container. Always compare labels when you buy a herbicide to determine if you are getting the same thing for the price.
Glysophate is used primarily for removing all plant growth at the beginning stages of food plot preparation, or when killing off an existing plot in order to change the plant species or to reseed a fading plot. In fact, Trudeau uses glysophate when he wants to create a brand new plot. He will typically spray the plot early in the spring when plants come out of winter dormancy and start to grow. When everything dies, he then disks the field. That brings up a new crop of seeds that sprout after a rain, and then he sprays again with a non-selective herbicide.
After that new crop of plant growth dies, Trudeau will disk again to bring up yet another crop of seed. In any field, especially one that has been left fallow for years, millions of seeds remain on the ground or in the top layer of soil, waiting for the right conditions to sprout. Disking will bring those seeds to the surface, where they present a new crop of weeds to deal with. By using a spray-disk-spray-disk rotation, it’s possible to reduce weed problems dramatically.
“I’ll disk and spray five or six times if I think that’s what is needed to knock down the weeds to a manageable level before I even think about putting down food plot seed,” he said. “It pays to be proactive on new plots or you’ll be fighting weeds for quite a while.”
When he sprays any herbicide, Trudeau will add either crop oil or a surfactant to the water-herbicide mix in his sprayer. In fact, some products simply won’t work without an additive, while others work much better with crop oil or surfactant. Both help the herbicide stick to the leaves better, and surfactants actually allow the chemicals to penetrate unwanted plants better. “You want to use a surfactant in herbicides that control broad-leaf weeds and crop oils in herbicides meant for grasses,” Trudeau said.
The best time to control weeds is when they are actively growing, but before they start to flower and produce a new crop of seeds. For some plants, that can be in the spring soon after they emerge, or in the fall just a few weeks after annual food plot plants take root and become established. Either way, the biggest mistake you can make is to wait too long. Once plants mature and start to drop seeds, the cycle of weed growth only gets worse.
Trudeau said it’s wise to spray only during cooler months, because the blistering heat of the summer can stress all plants significantly. Selective herbicides won’t usually kill the plants they are designed to benefit, but any undue stress can weaken them. Besides, many plants go dormant in the summer as they try to protect themselves from high heat and low moisture. Grasses in particular grow very little during the hottest months. In order for any herbicide to work, it has to be absorbed through the leaves and carried to the roots. That won’t happen when a plant is dormant.
Control Without Chemicals
Trudeau said herbicides aren’t the only way to control weeds. He mows his perennial fields at least twice each year. Of course, mowing works only on perennial plants like clover, and mowing annuals like brassicas will only inhibit their growth. Fall-planted annuals typically don’t need to be mowed, either, but annuals like clover and alfalfa will benefit immensely from periodic cuttings.
“Mowing stimulates new growth if it’s timed right. I typically mow once in the late spring before the plants start to flower and again in the fall after we get cooler temperatures and some rain,” explained Trudeau. “I would never recommend mowing in the summer, because the plants are under a huge amount of stress then. Mowing when it’s really hot and dry will do more harm than good.”
Mowing helps reduce weed growth because it can kill some unwanted plants, and it inhibits the growth of weeds in subsequent years by cutting off seed heads before they mature. Trudeau recommends mowing clover when it reaches 6 or 8 inches.
“Don’t mow it right down to the ground,” he said. “Instead, keep your blade high enough to take off the very top of the highest plants. The shorter plants won’t get cut, and the taller ones will regrow vigorously. Keeping food plot plants high will also help shade out competing weed growth.”
In most cases, mowing can’t control all the weeds all the time. Some hunters refuse to put herbicides on their plots for one simple reason: The notion of putting chemicals on the ground — and in the air — is frightening. It’s a legitimate concern, but when done properly, herbicide application is completely safe. Every herbicide, whether for use on food crops by professional farmers or for general use by gardeners and hunters, is tested thoroughly by the Environmental Protection Agency. They go through rigorous procedures to examine every possible risk before they are approved for the public. Stronger, more dangerous herbicides aren’t available over the counter and can only be used by licensed professionals. Hunters who want to control weeds in their plots only need to follow basic safety procedures.
“Wear safety equipment like goggles or glasses to protect your eyes, and wear gloves to avoid contact with your skin,” said Trudeau. “Avoid spraying on a windy day, and wear long-sleeve shirts and long pants. Wash exposed skin when you finish spraying and take off the clothes you wore while you were spraying and wash them, too.”
The Bottom Line
Herbicides, like pretty much everything else associated with food plots these days, aren’t cheap. A gallon concentrate of non-selective herbicide like Roundup can set you back $100, and a quart of grass-specific herbicide can run as much as $30 for just a half-acre’s worth. But Trudeau wonders why anyone who would go to the trouble and expense of planting food plots in the first place is hesitant to spend the extra money on the right herbicide.
“If you’re going to do it,” he said, “you might as well do it right.”
This article was published in the October, 2008 edition of Buckmasters Whitetail Magazine. Join today to have Buckmasters delivered to your home.