SAVING THE SOURLANDS: The destructive emerald ash borer is no match for the volunteers and staff from the Sourland Conservancy, who planted 10,000 trees over the past year to restore the forest and reduce the impact of ash decline caused by the insects.

By Anne Levin

In an unprecedented effort, a massive tree-planting project has helped save the Sourlands from the devastating effects of the invasive insect known as the emerald ash borer. This past year, a mix of volunteers and staff from nonprofits, land trusts, counties, and municipalities, as well as private residents, have managed to get 10,000 new trees into the ground at the 90-square-mile Sourland region.

“We’ve never done anything to this scale before,” said Carolyn Klaube, stewardship director of the small, nonprofit Sourland Conservancy. “But when we realized how many trees were dying because of the emerald ash borer, we knew we had to do something.”

The New Jersey Forest service alerted the Conservancy in March 2020 that, due to the insects, the region could lose more than 1 million trees within the next few years. That number represents approximately one of every five trees throughout the region, according to a press release.

It wasn’t just the emerald ash borer that caused havoc. In July, a tornado ripped through 230 acres of mature forest on Baldpate Mountain, already victim to the insects. Hurricanes Henri and Ida also left their mark, with flooding that “scoured streambeds and resulted in the loss of lives as well as serious damage to homes, farms, businesses, and natural areas throughout the region,” reads the release. “Trees help filter water, stabilize stream banks, and reduce stormwater runoff. The loss of 1 million trees is expected to exacerbate the effects of climate change, and could result in more serious flooding in the future.”

The Conservancy reached out and received help from the Mercer County Park Commission, Hopewell Valley Open Space, The Watershed Institute, D&R Greenway, and Montgomery Friends of Open Space, among other organizations. Students from the College of New Jersey, Raritan Valley Community College, Princeton University, and Rutgers University pitched in. Seasonal interns were hired by the Conservancy for the first time, enlarging the staff by 30 percent.

“Some of the areas losing trees are hard to access, so we trained the interns to be able to go into them,” said Klaube of the group, which ranged from 18-35 years of age. “They were exceptional, every one of them. They really took things very seriously and were very thoughtful in their work. At one of our group plantings, where we planted 2,700 trees, they noticed that they had been planted too high. So they dug them out and replanted them. The level of caring and attention to detail was phenomenal.”

Various grants aided the effort. The Currey Wilson Family Fund covered some of the work on deer protection. The New Jersey Nature Conservancy donated tree tubes, which are essential in riparian plantings.
Pinelands Nursery offered technical expertise to volunteers who would like to propagate their own native seedlings. The Conservancy is partnering with Raritan Valley Community College to collect data on the restoration projects.

“It is important to understand how effective our restoration projects are, and in order to do that, we need to collect and analyze data from our restoration areas,” said Klaube.

The Washington Crossing Audubon Society is working with the conservancy to train volunteers to conduct bird surveys and record the impact of forest restoration on native and migratory populations. The region is one of 113 across the country to be designated a Continental IBA (Important Bird Area) macrosite by the National Audubon Society.

Considering that some 2,000 trees were planted in the Sourlands last year, the fact that 10,000 went into the ground this year is impressive. “The cooperation with other municipalities and organizations is really a coming together that is so moving,” said Klaube. “People really cared a lot. They pitched in with what they could — trees, fencing, staff time, planting — all working together, and we were able to do something really great. That’s the message we have to move forward with. This is where we live; this is our forest. And we need to take care of it.”