Weeds never die, but the farmer who neglects to weed, surely comes to need.
That was the message March 6 at the 2010 Quality Forage Program, which attracted about 50 small-to-large acreage farmers and small-to-large animal producers. Sponsor exhibits in the Benton County Fairgrounds Auditorium in Bentonville, Ark., featured equipment and forage management products and services.
“I remember when,” is the common lament Blair Griffen, a University of Arkansas extension agent from Johnson County, often hears among farmers. Ignoring a few sporadic weeds in the pasture one year often leads to extensive overgrowth a few short years later. Weed control then becomes unmanageable and costly, thereby severely impacting crop and forage production.
Eliminating unwanted vegetation in pasture and hay is as simple as first spraying, then controlling existing weeds. Without crop protection, weeds grow among crops and compete for light, water and nutrients that are available in limited supply. Most weeds adapt to poor soil conditions, so soil testing helps establish a base line for beginning a lime and fertilization program. During harvest, weeds can wreck a combine or slow progress in the field.
Farmers should determine the extent of field damage by weeds and follow integrated weed-control systems before settling on one particular control method, such as mechanical, chemical or biological. The best way to accomplish this is by controlling weeds before they damage crops and before seeds shed. Mechanical methods include hand pulling, hand hoeing, tillage, crop rotation and burning. Biological control includes the use of animals or insect/fungus organisms that live on specific weeds, while chemical control – arguably the most effective of all – refers to herbicides.
Controlling weeds when small in size and number is financially advantageous to farmers, yet that concept has proven the most elusive, Griffen said. That’s because farmers’ typical cultivation problems include lack of management (such as fertility, lime and overgrazing) and lack of weed control and weed-control knowledge.
Weed Control Beginnings
To minimize weeds, farmers generally begin by pulling weeds by hand, tilling the soil several times before planting and applying various herbicides year-round. Weeds lead to quality, quantity and yield reductions, and control costs can exceed the yield’s monetary value.
Goats make good use of standard forage and are an excellent source of weed control, said Jack Boles, a Newton County extension agent. “If you pay attention to how a goat grazes, you can use that characteristic to your benefit,” said Boles, who suggested that farmers consider adding one to three goats per head of cattle. “Forage is the cheapest feed that exists for a ruminant, including goats which are a living, breathing harvester. Goats are top-down grazers, which assists in weed and parasite management.”
“Before herbicides, we used to walk the field to pull weeds,” said Bob Brown, who lives on an inherited Benton County farm. Timeliness and convenience are two main reasons Brown cites for chemical weed control. The development of crop-protection chemicals, like 2,4-D, has changed farming for the better because there was a time when tillage wore out the soil. “Our crops now don’t compete with the weeds like they did when I was growing up. Adapting is a key reason why we’ve been in operation for more than a hundred years. We only do one tillage pass a season; it has eliminated a lot of cross trips, which saves fuel, time and erosion.”
Crop protection helps the farm reduce fuel consumption because farmers have the ability to cross more acreage with fewer passes of weed application. The majority of farmers have adopted chemical over mechanical and cultural methods of weed control because it is yield-increasing and risk-reducing.
Before getting to that point, farmers need to accurately distinguish among weeds in order to effectively manage unwanted vegetation. Griffen encouraged those farmers in attendance to put questionable weeds in a plastic baggie, then drop it off at the county extension agents’ offices for proper identification. Even e-mailing a digital picture is an effective first step, he said.
Part of the battle also is in knowing the time of year, location and type of terrain where weeds grow as well as growth habits, leaf shapes and plant size. Buttercup and thistle are common winter weeds whereas bitter sneezeweed, pigweeds, wooly croton and horsenettle thrive in summer. Buttercup is the easiest to control winter weed, yet it is the most pervasive among area farms from December to March. Bitter sneezeweed thrives during the summer months on farms with low fertility soil. Both weeds, Griffen explained, are easily controlled when less than 3 inches tall and with 2,4-D, Grazon or Cimarron in one’s arsenal of weed control chemicals.
The drawback is that most farmers use one chemical year after year to control weeds. After 10 to 20 years of consistently relying on one method of weed control, the chemical loses its effectiveness because the weeds have built up a resistance to the applications, Griffen said. Regional farmers also must learn to reduce their dependence upon chicken litter and adapt to commercial fertilizers, noted Robert Seay, a Benton County extension agent.
With commercial fertilizers, it is important that a farmer look at the time of the application, dosage rates, labeling, mixtures and the overall safety measures that comes with the use of chemicals, said Johnny Gunsaulis, a Washington County extension agent for the University of Arkansas.
Forage remains the cheapest feed a farmer can use to feed his livestock at any time of the year, said Seay, who believes with the correct weed-cultivation methods, Bermuda hay can remain a viable option for regional producers who want to get the most out of their pastures and hay crop. Bermuda is a warm season grass that thrives full sunlight, thus anything that competes with it for sunlight, moisture or fertility serves to weaken it, Seay said. Pasture preparation is essential.
“It’s difficult to manage your pasture if it’s overstocked and overgrazed,” Seay said.