In the last blog I talked about timbered areas and some general thoughts about how and why we need to take an active role in managing them. In this blog I will take a look at grassland areas. Where you live you may also have wetlands or low-lying areas that are not timbered and aren't typically covered with grasses either. However, for the majority of us our wildlife habitat is either wooded or not wooded. Roughly 50% of the acreage at Maple Hill Farm could be considered a grassland habitat. At one time I would guesstimate that nearly 90% of Maple Hill Farm was native warm season grasslands, the remainder was oak/hickory savanna. Agricultural row crops and food plots can take a percentage of land out of both grassland and timbered habitat, but the other leading factor for loss of quality grassland habitat is the lack of management. Just like timbered areas, grassland habitat requires some type of active management from the Missouri River eastward probably even farther west than that if it is to remain a grassland. What happens to grasslands that are not actively managed? At some point they become woodlands. For many of us in the Midwest, fire was a common occurrence in the past and kept woody vegetation to a minimum or at least eliminated those species that were not fire adapted. Depending on the wildlife species that you wish to manage for, grasslands are very important. Healthy grasslands are not just composed of grasses, forbs (broad leafed plants) are often scattered amongst the grasses taking root in bare or disturbed areas. Those forbs are essential for many species, including deer, turkey and quail in terms of providing food and brood rearing habitat. Areas devoid of forbs might make suitable bedding or nesting cover, but overall that type of habitat does not need to occupy a large percentage of the total area. Grasslands that are not actively managed can quickly become overrun with invasive tree species. At Maple Hill Farm we have a problem with Eastern Red Cedar, Honey Locust and Osage Orange Hedge growing in grassland areas. All three species are prolific seed producers as well as being resistant to browsing (thorns on the locust and hedge and "leaf" tissue that is not very palatable on the cedars). In some areas native warm season grasses have also been removed and cool season forage grasses like brome and fescue have been planted. Neither of those grass species are beneficial to the wildlife species we are managing for. Deer do not typically consume grass and cool season, sod forming grasses are low in forbs and insects both of which are the primary diet of quail and turkeys at times of the year. Heavy layers of cool season grass duff also inhibit the movement of newly hatched chicks.
Eastern Red Cedar Osage Orange Hedge Honey Locust
So how do we manage for better grassland habitat? Prescribed fire is a great tool where it can be implemented. In some instances though the woody encroachment might be so severe that fire alone will not be sufficient to remove the woody vegetation. Heavy tree cover can reduce fuel loads on the ground to the point where it is difficult to keep a fire going. In areas with a light fuel load fire will not cause enough damage to mature trees to kill them. Often it will be necessary to cut down the mature trees and allow them to dry out prior to burning. We covered the general techniques to deal with "trash trees" in the Timber Stand Improvement blog. Since elimination of the trees is generally the goal in grassland management, herbicide application to stumps is necessary for most species. Cedar tree stumps that have no vegetation remaining do not need to be treated with herbicide and they will not resprout.
Without the use of fire the only way to permanently control woody vegetation in grasslands is with herbicide, unfortunately most herbicides will also significantly reduce the amount of forbs present. Mowing with a heavy-duty mower can temporarily remove the woody vegetation, but without herbicide application most woody species will resprout from the remaining stump of the tree. The exception would be the removal of cedar trees with a tree shearing or forestry mulching head as cedars will not re-sprout from flush cut stumps.
Grassland areas can have a woody shrub component to them which is essential for turkey nesting habitat and quail escape cover. Invasive trees aren't the only threat to quality grassland areas. If a grassland has been converted to cool season, sod forming pasture then you will need to eradicate the majority of the grass before proceeding with reseeding of more desirable grass and forb species. A non-selective herbicide application with glyphosate will likely need to be done and likely more than once. Non-native, cool season grasses typically green up earlier in the Spring than most native grasses that are often planted for wildlife, so the cool season grasses often out compete the native grasses if allowed to persist. Once established native grasslands can be maintained by appropriate grazing and/or light discing can help to encourage forb growth. Overtime without any disturbance grasses tend to out compete forbs, and the forb component of your grassland will be reduced. One of the major projects at Maple Hill Farm is to return the poor-quality, cool season grass pastures which have been infested with locust, hedge and cedar trees into native warm season grasses with a high percentage of forbs. It will be a multi-year project but one that will greatly increase wildlife usage of the farm. I will talk about more grassland renovation at Maple Hill Farm in future blogs.