In the eastern half of Kansas, the majority of Tallgrass Prairie was tilled under years ago for productive farming. Many of the remaining acres have been planted to introduce grass species like smooth brome and tall fescue.
Today, much of the remnant prairie persists as hay meadows or isolated parcels of rangeland. For those operations that are fortunate enough to still have some native range, encroachment of tall fescue can be a major problem.
Tall fescue is a cool season grass that offers quality forage in the early spring and fall. Native grass is predominantly warm season and offers forage during the summer months. Although these grasses would seem to complement one another, they cannot persist in balance within the same pasture.
Fescue requires fertilizer inputs to produce high quality forage and remain competitive among other grasses. Native grass requires regular prescribed fire to maintain quality, health and vigor. Thus, the two are fierce competitors for the limited resources available on any given piece of ground.
If you are one of the many livestock producers in eastern Kansas faced with a tall fescue invasion in your native grasslands, there are a few tactics you can use to control the fescue and maintain the biological integrity of your native grass.
- Prescribed fire is by far the most economical way to select against tall fescue. Properly timed burns later in the spring (i.e. April 15 through May 15) would be sufficient to keep the fescue at bay and allow your native grass to flourish. By looking at the growth curves, one can see that the timing of burn will impact the tall fescue at its peak growth. Burning in the summer can also help select against fescue in your native grass stands but take more planning to build fuel loads prior to the burn and reduced grazing pressure the year of the burn.
- Proper stocking rates are a great tool in the fight against fescue encroachment. Proper grazing allows native grass to flourish by maintaining proper leaf heights and vigor. A healthy native grass stand will better resist invasion of undesirable species (i.e. fescue) due to intense competition from the native grass. A stocking rate that is balanced based on season of use is critical. Livestock will not consume much of the tall fescue during summer if they have other forage choices within the grazing unit. Overgrazing the desired warm season grasses is a sure fire way to allow invasive plants to take root in your native grass stands and reduce the quality and quantity of forage produced.
- Prescribed grazing is the use of livestock to graze in proper numbers at key times to utilize the highest quality forage available. The prescription incorporates rest into the grazing system in order to encourage proper regrowth of desirable species. For instance, a livestock producer might graze from March 1 through April 30 and again on Oct. 15 through Dec. 15 to utilize fescue in a native stand of grass and give rest to the native grasses May through September. In essence, manage for what you want. Manage the native grasses so they maintain adequate leaf heights during active growth. Manage against tall fescue by grazing it late spring and fall.
- Brush management can be performed to remove the shading that limits native warm season grass production. Tree and shrub canopies provide an environment that favors cool-season grass and overall lowered grass production. Use treatments that are specific to the brush species you are targeting.
- Cutting height and timing are key concepts to address when managing hay meadows. Make sure the cutting machine is leaving a 3-inch to 4-inch leafy stubble behind and being done no later than mid-July. If haying later, move the cutting height up and leave 5 inches or more due to the shorter window of recovery for the native grasses before frost. When managing meadows that are weakened, you may consider cutting the field in June to improve the vigor of native grasses.
- Fertilizer should not be applied to native grasses that are having tall fescue invasion concerns. Fertilization may have been one of the reasons that tall fescue became a concern, especially in the absence of prescribed fire. Although forage production can be increased with fertility, often it is not economically feasible to apply and the increased potential of cool-season invasion makes it very costly.
- Herbicides offer another means to control tall fescue within native grass stands. This tactic should be used only after all other tactics have been properly implemented and concerns still exist. Herbicides can be applied during the growing season and in late fall. However, the herbicide labels must be strictly followed and errors could result in damage to the health and vigor of your native grass.