Site preparation enhances seedling survival by reducing competing vegetation. It also makes an area easier to plant. The technique used depends on soil type, slope, condition of the site, existing natural vegetation, and cost. Soils, slope, and ground cover are the three principal factors that determine the potential for erosion on any site. In Indiana, site preparation is often done by hand, mechanically, or with the use of herbicides.
Mechanical and Hand Clearing
Mechanical site preparation involves the use of heavy equipment to clear the planting site of unwanted vegetation or planting obstructions. This may be as simple as plowing and discing an area of dense sod, or as major as completely clearing a site of undesirable trees (such as honey locust). The BMP goals are to keep the soil on-site, avoid stream sedimentation and maintain site drainage. When mechanical site preparation is necessary, consider these guidelines.
General Guidelines
- Limit clearing to stable slopes. Do not use heavy equipment to clear highly erodible areas or steep slopes (i.e. >20%).
- On steep slopes cut or girdle unwanted trees by hand and leave felled material on the site.
- Avoid removing the forest's litter layer as much as possible on slopes. This can be done by hand clearing or using a raised dozer blade to move only woody material and avoid soil gouging. Do not expose more than 50% of the soil surface. Clearing while the ground is frozen will help minimize soil disturbance.
- Do not operate under wet soil conditions.
- Stabilize bare soil areas on cleared sites with a temporary cover crop. Do not use noxious and non-native perennial species such as Kentucky 31 fescue and alfalfa unless needed for highly erosive soils. (See table of seeding mixtures).
- Do not place cleared material in RMZs, sensitive wetlands, or where it may block area drainage.
- Maintain an undisturbed buffer strip next to watercourses and sinkhole openings.
Warning: The Indiana Flood Control Act prohibits the construction and placing of fill, including woody debris, in floodway areas. Clearing in designated "floodways" may require a permit from the Indiana Department of Natural Resources, Division of Water. Heavy clearing in designated wetlands may also require a permit. For information call the Division of Water at 317-232-4160 or the Division of Forestry at 317-232-4105.
Chemical Site Preparation
Several herbicides may be used to eliminate weed competition or undesirable trees. With herbicides, there is no soil disturbance. They can be used where steep slopes prevent the use of machinery. Nevertheless, there are also risks in the use of herbicides. The following guidelines minimize these risks.
General Guidelines
- Always use the proper herbicide for the job and follow label instructions! The herbicide label is a legal document. Some herbicides are labeled as "restricted use" and must be applied by licensed individuals. If in doubt, contact a trained forester or herbicide dealer.
- Do not apply near watercourses, sinkholes, springs, or seeps.
- Maintain a buffer strip of at least 50' next to streams and water bodies to act as filters of any moving herbicides. When planting immediately next to streams, contact a trained forester for specific herbicide recommendations.
- Do not use broadcast herbicide applications where excessive runoff will be a problem.
- Do not apply herbicide sprays during windy periods.