In Oklahoma and other surrounding states, summer prescribed fires are a common form of mitigation for cedar trees, which hinder cattle producers. Along with cedar-tree control, prescribed burns offer a number of benefits to livestock producers and wildlife habitats, says John Weir, associate extension specialist of prescribed fire at Oklahoma State University (OSU).
“A prescribed burn is a fire that is set on a specific area of land for specific goals and objectives,” Weir says.
July through September are the best months for a prescribed burn, according to the Oklahoma Prescribed Burning Handbook.
Chuck Coffey, owner of a family cattle operation in the Arbuckle Mountains of Oklahoma, says his ranch has three primary goals of summer burns. The first reason is the eradication of cedar trees.
“The second reason we burn would be for the environment, to produce an ecological response from the grasses because these native grasses have evolved under the influence of fire,” Coffey says.
The third reason is to improve grazing for their cattle herd. A summer burn can improve crude protein of forage from 5% to 12% in the winter, he says.
Weir says cattle gains can be increased from 10% to 15%, which is a considerable advantage. After a burn, a majority of the old forage is removed, allowing for tender, succulent and more palatable growth to replace it. Therefore, cattle consume forage with a greater nutrient content.
Prescribed burns can alter cattle’s grazing patterns by encouraging them to graze where they normally would not, Weir says.
“Fire and livestock should coexist, and they should be thought of together because [a prescribed burn] does nothing but help the livestock,” says Seth Coffey, Chuck Coffey’s son who studied fire ecology as a master’s student at OSU.
Similar to the benefits for livestock, prescribed burns change habitat structure for various species and change plant characteristics to make the forage more desirable, Weir says.
“I’m of the opinion that what’s good for wildlife is also good for cattle when it comes to managing the native lands,” Chuck Coffey says.
Chuck Coffey’s ranch consists primarily of native grasslands, including big blue, little blue, indian, switch and silver bluestem grasses. The need for fire to germinate these grass seeds is crucial, Coffey says. “It’s my understanding from research that… the presence of smoke within a seed, or the heat, stratifies a lot of these seeds.”
Chuck Coffey says the increase in diversity of wildlife from summer burns is another great benefit, but one must consider environmental conditions when planning a summer prescribed burn, including humidity, wind speed and temperature.
“The most important factor is fuel load,” Coffey says. “It may take two or three years for us to build up the 3,000 pounds of fuel load that we’re looking for.”
Another factor to consider is stocking rate. The number of cattle in a pasture and the amount of forage in the area can affect how often the owner should burn the land. “I never burn more than once a year on any piece of ground,” Coffey says.
Weir says the temperature is not as important to consider for summer burns as it is for spring burns. The effect the temperature has on the crew is the main consideration in summer.
“Typically, relative humidity is anywhere from 25% to 70%, winds from 5 to 20 miles per hour [in summer],” Weir says. In contrast to winter or spring burns, summer burns have less risk. A summer fire can do well with lower humidity and more wind speed to carry the fire, he says.
“We don’t make the call of the fire until the morning of,” Chuck Coffey says. “If the conditions don’t fit our description, then we don’t light.”
If the removal of brush is the goal for the burn, Coffey says he prefers humidity to be between 40% and 60% with wind speeds from 10 to 15 mph. These conditions are different than burning in the spring, he says. In spring, he would want a cool fire so it would move rapidly.
“If I am wanting to control cedar, … I want humidity to get really low, and I don’t want a fire moving too quickly over the area because there’s two things that will kill a tree – intensity and duration,” Coffey says.
Seth Coffey says summer fires are more effective for killing brush and cedar trees because the plant cells of a tree need to reach 140º to kill it. In the summer, when it is already 100º, it is easier to increase the temperature of a tree 40º rather than 70º or more in spring, he adds.
Checking the weather forecast constantly and watching the direction of the smoke is a crucial part of a safe prescribed fire, Seth Coffey says.
“We do produce a little more smoke in growing season or with summer fires,” Weir says. “But this is offset because we have a lot better atmospheric conditions for smoke dispersion in the summer months.”
Although summer prescribed fires are less dangerous than spring burns, it is vital to properly plan the burn to ensure safety. “One of the main things you need to do is have a written fire plan,” Weir says. This plan should cover the goals of the burn and the safety precautions before and during the burn. The plan should include optimal weather conditions, types of fire breaks to be used, equipment needed, local fire stations and neighbors to be contacted, and pre- and post-burn management, he says.
“There are a lot of different things we can think about to make burning simpler and easier,” Weir says. For example, he recommends fire breaks be wide enough for vehicle equipment to be able to access them.
Landowners need to contact all adjoining neighbors and nearby fire stations to notify them prior to the burn, Chuck Coffey says. In addition, he stresses the need to share the fire plan with everyone who will help with the burn to establish clear communication.
Fires can transform previously dead plants and brush into usable, edible forage for livestock, Seth Coffey says. The benefits of summer prescribed burns to livestock producers and landowners are numerous, he adds.
“[A prescribed burn] is the cheapest and one of the most effective tools for a landowner,” Seth Coffey says.