Mt. Cuba Center in Hockessin will reopen Saturday, more than a week after the Aug. 7 storm knocked down more than 200 trees and trapped 11 staff members in the main house on the property for about four hours.
The Friday night storm “is in the top three worst since I’ve been here,” said Bill Trescott, the center’s arboriculture manager. “And that counts winter storms as well. Some of those have been pretty bad.”
Mt. Cuba estimates that 30 trees went down in the gardens, and that about 200 went down in the forested area of the center’s 1,000 acres.
The storm has reinforced Mt. Cuba’s plans to garden for climate change and prepare for more damaging storms. That means considering the best plants to replace downed ones so they’ll still be standing in 50 years if the weather continues warming. It also means new and different equipment may be needed, along with more help from vendors who already own that specialized equipment.
Friday’s tornado traveled near the center’s property, but not through it, Trescott said. He believes the straight-line wind damage that night went through the property because all the trees were pushed over in one direction.
According to the National Weather Service, the wind line had maximum gusts of 95 mph and moved from Greenville to Wilmington for 4.51 miles. Mt. Cuba also had an inch of rain in five minutes and four inches in an hour, causing flooding.
“It was intense. From what I understand, it was howling up here,” Trescott said. “Trees just can’t take that.”
When the storm hit, about 11 staff members were in the main house. They couldn’t get off the property for three or four hours because all the surrounding roads were either flooded, had wires down or trees blocking the way out.
Staff rescued them by parking on a remote section of the property and then walking in by foot. They cut their way out to Barley Mill Road.
On Wednesday, Trescott said about two-thirds of the gardens were in decent shape.
When opened to the public, a few of the garden areas may be cornered off, but the circulation paths will be accessible as well the guest parking lot and main house.
However, the storm destroyed the picnic area near the guest parking lot. It’s now full of downed trees.
“It’s pretty stark. There’s a lot of trees missing,” Trescott said.
But the winds didn’t touch an allée of trees near the house that are diseased and need to come down. Mt. Cuba will still have to cut the trees down to create a new area for visitors to picnic and rest in the shade.
Trescott has worked on the property since 1985. He ranks the damage from Friday’s storm with that of Hurricane Isabel in 2003 and some bad downdraft wind damage in the 90s.
Cleanup will be extremely costly, he said.
Mt. Cuba, a former du Pont estate, recently won the top spot in USA Today’s Best Readers’ Choice Award for “Best Botanical Garden” in North America. It specializes in native plants and ecosystems.
The worst damage to structures was a tree falling through a garage, Trescott said.
Job one in taking care of Mt. Cuba was to make sure that roads and pathways were clear. Job two was to make sure any trees that didn’t fall all the way came down so they don’t fall on someone or some property.
Some of that requires specialized equipment that can lift the leaning trees off the ones supporting them, Trescott said.
Recovering from damage means different things for the gardens and for its forested areas.
The downed trees in the forest largely will be left as they are, unless they are a danger to someone, said Nathan Shampine, natural lands manager. Trees will be removed from paths and grasslands.
“We understand that these natural disturbances happen occasionally,” Shampine said, “and that it will create openings for new growth and allow for the successional process to start again.”
The downed trees leave holes in the canopy, which will allow light through and some of the native plants and seedling trees to grow. That creates a younger forest area in the midst of the old, a natural renewal, he said.
“It is thought that with climate change, we will experience more frequent and intense weather events,” Shampine said. “We know we’re going to have tornadoes and hurricanes. How we manage our natural areas is for resiliency, adaptability and function, with diverse native plant species as the foundation.”
In the gardens area, horticulturists generally choose what to plant, focusing on individual plants rather than groups.
The gardens would not cut down trees because they are old, Trescott said. But if a tree is knocked down by a storm, it may not be replaced with the same kind of tree.
Tulip poplars and white pines tend to be brittle trees that don’t withstand wild weather events, Trescott said. Those that are knocked down are likely to be replaced by oaks or nyssa, also called tupelos.
Because the climate is expected to heat up in the coming decades, Mt. Cuba also plans to experiment by planting trees that flourish a bit south of Delaware. The trick, Trescott said, is whether those trees can weather Delaware’s winters, which can get bitterly cold.
“A cold snap can do a lot of damage to those trees from another region,” Trescott said.
Some of the new trees may be grown from seedlings that have developed naturally on the grounds. Those tend to be the hardiest replacements.
Trescott said that if the gardens continue to face worse storms, it may need to invest in some special equipment. The cranes needed to work on tall trees in small spaces now are smaller than the ones Mt. Cuba owns and can fit through gates that are 36- to 40-inches wide. They are critical to clearing up trees that fall on buildings, he said.
Mt. Cuba is fortunate to have access to several vendors who have that equipment. The center used some vendors to help clean up things like the tree on the garage, he said.
More equipment and more help to deal with major storm damage is on Trescott’s wish list, he said.
For the moment, though, he said all he was worried about was the Friday afternoon forecast, which called for thunderstorms.
The center didn’t need a flash flood, he said.