Volunteers scramble to save trees from gypsy moth caterpillars

A group of volunteers will spend the next several months pulling invasive gypsy moth caterpillars from trees, and destroying them, before the insects defoliate an urban park in Ottawa.

The gypsy moth caterpillarruns only four to six centimetres long, but that minor insect posesa massive threat to Ontario's forest cover.

Scientists warnthat 2021 shapesup to be abumper year for the invasive species, brought to North America around 1860by aFrench entomologist who hoped to cross-breed them with silkworms.

With the help of fellow tree protectors, Sharon Boddyvisitsthe 11-hectare Hampton Park nearly every afternoon wrapping trees in burlap and hand-picking the caterpillars off tree trunks and branches.

She then kills them off with soapy water.

"We're in year two of an infestation and it's hitting Ontario really, really badly," Boddy said.

"We need to get a jump on it nowbecause this isn't the last year."

Boddy says the work, which can sometimes get a little messy,will continue into the fall and she hopes to recruit more volunteers along the way.

"The worst part is getting rid of them after they're dead," Boddy said. "Sometimes we'll come across the pupae and they kind of squirt at you."

Sharon Boddy talks about protecting trees from gypsy mothcaterpillars:

Volunteers work to thwart invasive LDD moth caterpillars in Hampton Park

3 years ago

Duration 1:45

Resident Sharon Boddy says many of the trees in Hampton Park are threatened by LDD moth caterpillars, driving volunteers to trap and remove as many of them as possible.

'It's pretty hard to control this'

Research scientist Christian Schmidtsaidthese insects don't have any natural predators because they are not native to Canada. They are not part of the natural food web.

"People have spent millions of dollars trying to control this thing over the decades," Schmidt said.

"It's unfortunately a situation of, once the cat is out of the bag, it's pretty hard to control this."

Whilealarming to see some trees completely defoliated by these bugs, Schmidt says he's not concerned about long-term damage as the population is cyclical and will eventually decrease.

He does commend the work of Boddy and other volunteers in Hampton Park.

"It's certainly beneficial to trees that are being severely defoliated because you're reducing the stress on that tree," Schmidtsaid.

"And in a year like this, when there's already drought conditions in the spring, trees are experiencing other stressors."

The City of Ottawa's forestry department said staff has monitored the situation closely and encourages residents to continue to physically remove caterpillars and wrap the trees with burlap.

The city has said they might beginintensive surveys to determine areas of concern, as well as communicate to residents and community groups about how to protect trees for next year's invasion.