The University of Delaware chapter of Ducks Unlimited assisted the Landmark Science and Engineering firm in putting trees back in place and adding an array of native plants in a new wetland mitigation area on UD’s Newark Farm on April 10.
The wetland mitigation area was created last fall and Amy Nazdrowicz, who received her master’s degree from UD’s Department of Entomology and Wildlife Ecology in the College of Agriculture and Natural Resources (CANR) and now works for Landmark as an environmental scientist, said that with late fall plantings it is not uncommon for the new trees to pop out of the ground as water freezes and thaws through the course of the winter.
That is especially true with the new wetland, the sixth on the UD Farm, which has a clay base.
“This wetland is holding a great deal of water. It’s not really infiltrating at all because the wetland has a clay layer,” Nazdrowicz said. “Sometimes we have to truck clay in to construct a wetland but for this one, the on-site soils were good.”
Mike Popovich, a research associate in the Department of Plant and Soil Sciences, said the problem with the clay base is that while it holds the water, it also expands and contracts as temperatures fluctuate.
“Over winter, we had some days where it was 40 degrees and then some days where it got down to 5 degrees, and it’s popping the trees right out of the ground,” he said.
Nazdrowicz said that the 275 trees and 175 shrubs planted in the wetland are all native species found in this region of Delaware, and that moving forward only native plants will be planted there.
“The native plants all have their own natural predators — things that eat them and things that use them for cover,” said Nazdrowicz.
While most of the wetland will be forested with native trees, Nazdrowicz explained that the site’s central basin will be emergent — an open canopied space dominated by herbaceous plants. In addition to re-planting the trees, the group will also plant 2,350 herbaceous plugs such as flowers, grasses and sedges.
“It’s really only the central basin that doesn’t have that many trees and shrubs. It has some shrubs in the deeper section but that’s where we’re going to plant a lot of these plugs,” said Nazdrowicz.
The actual planting of the exposed areas of soil with the plugs was done on April 12 with the help of UD students, as the group had to wait for the water in the wetland to recede before planting.
Chris Williams, associate professor of entomology and wildlife ecology, director of the Waterfowl and Upland Gamebird Program and adviser of the Ducks Unlimited student chapter, said he was “excited about the new wetland restoration and happy the students could gain hands-on experience toward its restoration.”
Williams added that because the area will become a forested wetland habitat, “it increases the chances that we can install wood duck boxes in the future to promote these very colorful ducks.”
The trees that were planted in the wetland will eventually grow to be very large and it will become a forested wetland that will sit next to and complement UD’s Ecology Woods.
“This is in the conservation easement and it will stay like this forever. These trees will eventually reach maturity years from now and they’ll eventually be just as big as the adjacent trees in the Ecology Woods,” said Nazdrowicz. “Right now, this is only year one and we’ve found better success rates when we use smaller plant materials, so these are only very young trees and shrubs.”
The team that designed and constructed the wetland mitigation area — the plans for which began in February 2014 — included:
- Nazdrowicz, whose responsibilities included wetland design, producing the wetland mitigation plan report, planting specifications, agency coordination, and plant installation and oversight. She also will oversee wetland monitoring.
- Colm DeAscanis, president of CDA Engineering Inc. who graduated from UD with a bachelor of science degree in civil and environmental engineering in 1996, and who designed the wetland and the swale and did the construction stake-out.
- Vince Dills, vice president of Merit Construction Engineers Inc. who graduated from UD with a bachelor of science degree in civil and environmental engineering, and who constructed the wetland and swale.
- Will Twupack, environmental scientist at Landmark Science and Engineering who was at the wetland April 10 and whose responsibilities include siting of the wetland construction area, the soil investigation, coordination with UD staff, wetland design, construction oversight and plant installation.
The group members thanked CANR Dean Mark Rieger, Tom Sims, professor in the Department of Plant and Soil Sciences, Popovich and Scott Hopkins, UD Farm superintendent, for their help with the project.
Article by Adam Thomas
Photos by Lindsay Yeager
This article can also be viewed on UDaily.