Boost productivity by picking the right machine or attachment.
Adding land clearing to your list of capabilities, rather than outsourcing this work, has many benefits. This work can help you keep crews busy between projects, maintain control of your project time frames, use your equipment efficiently and keep more cash at project completion. But you might be in for a surprise if you think,“It’s only lot clearing. How hard can it be?” Removing unwanted vegetation is not rocket science, but aspects of it can make a seemingly simple project much more complicated. When clearing land, use these best practices to ensure you do this work as efficiently as possible.
Chippers vs. Mulchers
Many contractors already have some equipment that can be used to clear unwanted vegetation. But just because a piece of equipment can be used for this, does not mean it should be. Take the standard chipper, for instance. While these machines can reduce brush and limbs and eliminate disposal concerns, they are not the most efficient way to remove brush.
Consider the manpower required to operate a chipper, which includes the person actually feeding limbs to the chipper, a couple of men hauling materials to the feeder and at least one or two workers felling trees and pruning limbs (which creates work for the haulers). In addition to the number of employees required on this site, safety is also a factor—chainsaws and falling trees and limbs are inherently dangerous.
Mechanical mulchers, on the other hand, allow one man to fell the trees and grind the downed trees and limbs into mulch. This operation is much safer than a hand-crew since it can be done by one person from a climate-controlled cab. The one-man/one-machine approach is also more productive because a single operator using a mulcher can clear more acreage than a five-man crew using a chipper.
Operating a mulcher is like operating any piece of heavy equipment—it is a learned skill. As operators use the equipment more, they will gain increased knowledge, confidence and productivity. Training one operator well is better than training a lot of them poorly.
The one-man/one-machine approach is also more sustainable. The mulched materials—left on-site to control erosion—are more uniform when processed by a mulching attachment. And because the shredded materials have plenty of surface area, they will decompose and add organic matter back to the soil (smooth-sided chips do not decompose well).
Mulching Attachments
Many mulching attachments are available to fit skid steers and excavators of virtually any size. Choosing which attachment to use is a personal decision. But first determine what you can use from your existing equipment. Each piece of equipment has benefits and limitations. Skid-steer mounted mulchers are very nimble and allow operators to quickly mulch around “keeper” trees while eliminating unwanted underbrush and vegetation. Because these rely on the carrier’s hydraulic system to power the mulcher head, it is vital to supply the proper hydraulic flow with a high-flow model. These mulchers can handle 4- to 6-inch diameter materials and the occasional 6- to 8-inch diameter tree, limb or log.
Skid steers have light footprints and create less ground disturbance than heavier carriers. In fact, newer models are built specifically to operate in sensitive areas because they exert low ground pressure. Depending on what your next construction project will be, this may be a consideration.
Excavator-mounted mulchers also rely on the carrier for hydraulic power. (An additional power pack can be used to power the mulcher head). They can also handle larger diameter materials compared to skid-steer mounted mulchers, and given the length of their stick-arms, they can attack vegetation from atop. Operators can place the mulcher on top of a tree and literally grind it down to the ground level. The tradeoff for this extra muscle is mobility—they are more cumbersome than skid steers and clear less acreage per hour.
When considering the attachment, look closely at the cutting teeth, and match them against the materials being processed. Often, we assume that the harder the wood, the harder it will be to grind, but the opposite is true. With ample horsepower, mulchers can grind through hardwoods easily, while softer woods like willows can be cumbersome because they are pliable. Again, ample horsepower and a proper cutting tool selection can go a long way toward ensuring success. Numerous cutting teeth styles are available. Some, like carbide tipped varieties, are better suited for heavier materials than chipper-style cutters, which are ideally suited for light brush. When in doubt, consult the manufacturer or equipment dealer.
A final consideration when reviewing equipment options is machine durability. No matter how good equipment looks on paper, it does not make you money (or save you any time) when it is in the shop. Whether down for routine maintenance or for extended repairs, downtime is a concern, especially if your projects will be in remote areas.
If the proper equipment is applied and run by conscientious operators, adding vegetation management to your list of capabilities can be beneficial to your company.
Construction Business Owner, May 2011
