Green Horizons

Editors’ note: The mention of specific manufacturers does not imply endorsement on the part of Green Horizons, the Missouri Department of Conservation, USDA NRCS, or the Southwest Missouri RC&D.

Very few parts of Missouri have been spared a devastating storm in the last couple of years. In many instances, forest landowners have been left with unsalvageable timber stands choked with downed trees, limbs and opportunistic vines taking advantage of the sudden sunlight.

The sustainability of your forest may be in question if the debris on the ground and the vine cover is so thick that new seedlings cannot get established, and trees with severely damaged tops cannot be cut back to encourage stump sprouts. In addition, all this downed material increases the potential for an intense forest fire; one that, if it does not outright kills your trees that made it through the storm, could create entry points for disease, insects and decay.

So, what are your options? First and foremost, think safety! Even a small sapling bent over has the potential to release its bound-up energy in a deadly way if cut improperly.

Next, consider how much "slash" you have on the ground. Slash refers to all the limbs, broken tops, and toppled trees that are on the ground.

Light slash treatments might simply involve what is commonly called "stomp and cut." A lightweight chainsaw is the perfect tool for cutting up larger material to get it close to the ground for speedier decomposition. This can be a great way to stay out of trouble, because you will be in the woods all the time! You can consider hiring RESPONSIBLE high school kids who know how to operate a chainsaw. Just make sure you have good liability insurance. Storm debris that has been on the ground longer than 18 months is dry and brittle and stems 3 inches diameter and smaller can be easily stomped to the ground.

For medium and heavy slash treatments, mechanized equipment will be the order of the day. Plus, with the operator being in an enclosed cab, the risk of personal injury is greatly reduced.

The forest hog and skid steer-mounted grinder heads (Fig 1 and 2, respectively) can easily work up debris up to 6 inches diameter. If there is quite a bit of material larger than that, it should be done using the dedicated FECON grinder (Fig 3). This unit can handle up to 12 inches, and sometimes larger. A common feature though is that they are track vehicles, so there is minimal soil compaction.

One thing to remember about grinding is that it cannot be used on steep ground. In these situations, one might consider pulling lighter weight stems to a flat landing using a log arch and four-wheeler, where they can easily be cut up for firewood. The trimmings from the transported stems can be left in piles that can be ground up using forestry grinding equipment.

One question posed by foresters was, "Will a ground stump resprout?" It was thought that maintaining the integrity of the root collar near the soil line (Fig. 4) would be critical to ensure successful sprouting. Fig. 5 shows that relatively large oak stumps ground completely to the ground can resprout. In fact, all species sprout back readily, so one must consider treating the stumps of undesirable species with a herbicide to avoid unwanted sprouts.

Last, but certainly not least, is cost. Commercial operators charge anywhere from $80/hour (Bobcat with grinder head) to $140/hour (FECON grinder operator). The USDA NRCS Environmental Quality Improvement Program (EQIP) provides financial cost sharing on a per acre basis.

The commercial hourly fees may cause confusion for landowners who want to know the per acre cost. With a light level of slash (downed debris that still allows access through almost all areas of the forest), expect a cost of $100-200/acre. With very heavy downed debris, making the forest all but impossible to walk through, expect to pay at least $600/acre. If you have a medium slash level (discontinuous and most stems less than four inches), walking in a straight line is not possible in most areas, but there are still routes you can take to get through your forest. Expect to pay somewhere between the light and heavy rate.

Experienced forest grinding operators can give you an idea of the cost when they look at the site and know the acreage involved. Some tree species, such as white oak and hickory, are harder for the machines to work on due to the stringy nature of the shattered wood, so keep that in mind when requesting a price quote from an operator.

Areas with boulders or large rocks will result in more damage to the grinding teeth and take longer to complete as the operator tries not to hit rock, hence a higher cost. Also, if you want residual mulch finely ground (i.e. around a woodland home), the operator will have to keep going back over the coarse, shredded mulch. For most forest management work, going over the debris one time with either a grinder head or a forest hog is sufficient.

For more information about the process and how to contact a contractor with the proper equipment, contact the Southwest Missouri RC&D office at 417-732-6485.

	Fig. 1. This forest hog can grind up to 6-inch debris.
Fig. 2. This skid-steermounted grinder can also process up to 6-inch material.
	Fig. 3. The Fecon grinder can easily grind 12-inch standing trees.
Fig. 4. Leaving a relatively high stump prevents damage to grinding head in rocky terrain.
	Fig. 5. Grinding down to ground line does not prevent sprouting