The Nature Conservancy - A Bulldozer for Conservation

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By Florence Chong

In most forests, the sight of a powerful bulldozer is a menacing one; an image associated with destruction and devastation. On the slopes of Mauna Loa, however, a bulldozer has become an unlikely conservation tool, helping to accelerate The Nature Conservancy’s forest restoration efforts in a variety of ways.

In 2006, the Conservancy bought a used Caterpillar D5 dozer at a significant discount for its Hawai‘i Island preserves. The idea for acquiring it came from Mel Johansen, the Conservancy’s Kona Hema Preserve Manager, who also happens to be a talented dozer operator and mechanic.

“You'd never expect that our most important conservation tool would be a bulldozer — but it is," said Rob Shallenberger, Director of Hawai‘i Island Programs for the Conservancy. “We now use it for fence line preparation, road repair, firebreak construction, scarification of the soil to promote koa regeneration, and the preparation of sites for the outplanting of rare species.”

This spring, Johansen used the bulldozer to prepare a fence line through pasturelands in the Kaiholena Unit of the Ka‘ū Preserve. Fencing is essential at this site to prevent pigs and mouflon sheep from entering and damaging the adjacent native forest.

A unique tool for conservation

Mel Johansen

Johansen, an eight-year veteran with the Conservancy, first used a dozer to construct a fence at its Kona Hema Preserve. A talented hunter, carpenter and mechanic, Johansen grew up in the south Kona community of Honamalino, where he had previously worked in logging and ranching. In making the transition to conservation, he quickly realized the many uses a dozer could fulfill. But until the D5 was acquired, he was forced to rent equipment at a substantially greater cost. With the dozer now on site, he saves time and money in fence construction and road maintenance.

“Kona Hema Preserve is within the agricultural zone where regulations permit use of heavy equipment,” he explained. “This would not be possible in conservation-zoned land, where fence lines must be cut by hand and materials must be carried on your back or airlifted by helicopter.”

Scarified area, Honomalino

According to Johansen, repairing the roads in the area with the bulldozer not only allows Conservancy trucks to reach the project areas faster, but there is significantly less wear and tear on the vehicles. Most importantly, staff can drive around the entire fenced perimeter of the Kona Hema Preserve on a regular basis, making it possible to find and remove trees that may have fallen on the fence. In this way, Conservancy staff can prevent the infiltration of pigs that could easily move through a breach in the fence.

Dramatic results have already been seen using the dozer for soil scarification on the Kona Hema Preserve. The dozer is used to turn over the soil surface. This enables the koa seeds that are covered with soil and invasive pasture grass to germinate. With the soil scarified, seeds that drop from the nearby koa trees now have a competitive advantage to take root.

Koa seedlings emerge from scarified soil.

“We have scarified more than 200 acres so far at a rate of five to 10 acres per day,” said Johansen. “Now these newly emerging seedlings can get the moisture and sun exposure they need to grow. Some of the seedlings which emerged in the last year are more than 10 feet in height.”

A fast responder to fires

While these results are exciting, Johansen noted that the single most important reason to have the dozer on the preserve is to respond in the event of wildfire. Conservancy field staff members are trained in fire suppression and are prepared to work closely with County and State firefighters to attack fire on the preserve. Having a bulldozer on site makes it possible to get ahead of a fire quickly and cut a firebreak. Without a bulldozer, it would take many more hours for help to arrive, and much more manpower would be needed to cut a fire line by hand.

Huge koa tree, Kona Hema Preserve “Having this bulldozer benefits the entire area, including our partners,” said Johansen. “The State Forest Reserves, the National Park, all of our neighbors — we would be the first to respond and ready to help them in the event of a fire.”

“Our goals here are not just to protect what we have, but to demonstrate that forest recovery is possible,” said Shallenberger. “With the right mix of techniques — fencing and the removal of pigs and sheep, fire protection and the scarification of soil — we will see the forest recover.”

“Bottom line,” Shallenberger added, “the dozer is an extremely important land management and habitat restoration tool that we would have a very hard time doing without.”

Check out other Conservation Spotlights stories >>

Nature picture credits (top to bottom, left to right): © John Replogle (Mel Johansen and bulldozer at Kaiholena); © Rob Shallenberger/TNS (koa seedlings, scarified soil); © Phil Spalding III (Mel with giant koa tree, Kona Hema).