Seeding and mulching erodable soils after timber harvesting

This web article explains how forest workers and landowners can use grass-like seed and mulch to control erosion after a timber harvest.

Seeding and mulching
The idea behind seeding forest roads, landings, and unprotected slopes is to encourage the development of dense roots that bind the soil, holding it in place, no matter the weather. Think of seeding as a way of improving the absorbency of forest soils. Mulching - with straw, woodchips, bark, or synthetic netting - retains soil and moisture for the growth of these grasses and other plants.

Mulch can be used without seeding if natural regeneration is desired. In these cases, wood chips or hay mulch will help protect the soil for weeks or months after logging is completed.

The process of seeding a logging work site requires:

1. Engineering to control the eroding force of water
2. Liming the soil to improve the pH level
3. Fertilizing the soil
4. Applying seed, and
5. Mulching the seed.

The top priority is to make sure seed comes in substantial contact with the surrounding soil, not just scattered on the surface. Hay mulch can contain its own seeds. Liming and fertilizing are important, but can be minimized if cost is a consideration.

Best management practices for seeding and mulching

Choose appropriate areas for seeding
Inspect a completed timber harvest, looking for exposed, sloping, or erosion-prone soils. Very often, this is soil not protected by a canopy of trees, saplings, and shrubs. Mark these areas with a new color of flagging to make clear where seeding should be applied. Landings and approaches to landings should always be seeded when equipment moves on. Sometimes, the seeding will be necessary in clearings to attract wildlife (requested by landowner).

Staff from the Soil and Water Conservation District can visit the site and help identify which areas should be seeded.

If the site has been harvested in the winter, apply a layer of woodchip mulch to provide at least some protection to the soil until seed can be applied.

Chose a good seed mixture
Seeds should encourage the growth of grasses and related plants in sunny or partly sunny areas. The mixture will have fast-germinating seeds that develop substantial root systems, and slower-germinating seeds that will take over and stabilize the site for years to come. In NY, a blend of annual ryegrass, creeping fescue, perennial ryegrass, redtop , and white clover makes an effective mix. Many sites are also successfully seeded with Lathco flatpea, which can tolerate shady onditions and still grow with vigor. Check with an Extension specialist, Soil and Water Conservation technician, or seed supplier for the most appropriate blend in your area. When in doubt, apply a general conservation mix.

Prepare the site to be seeded
First, control and slow down water that might flow through newly seeded area with a water bar, turnout, or other water control technique. Re-spread topsoil to provide a fertile base. Test the soil for fertilizer or liming needs. Remove surface debris and spread the seed by hand or with a broadcast spreader.

Consult with the county Soil and Water Conservation District for information on conservation seeding and special hydroseeding equipment they may have to borrow.