The local trees that received a bad haircut earlier this summer from an infestation of tent caterpillars seem to be recovering well.
"Some varieties of trees took a hit but most that were ravaged are starting to come back, we are seeing re-growth of the leaves," said Flavio Viola, the city's manager of parks. "Any trees that don't make it, we will be replacing but we expect a good survival rate."
The municipality did do little to ward off the little plague of caterpillars, since "they were really more of a nuisance," Viola said. They "might have seemed a little gross" but were doing no damage to public values or private property. Consequently, investing staff time and taxpayer money into fighting back would deliver little in the way of results.
Jim Good at Goodsir Nature Park north of the city saw the creepy crawlers swarm over the 160 acres of rare trees and flowers, knowing there was little he could do to halt their advance. They devoured the aspen leaves first, before making meals of the cottonwood greenery, the Saskatoon foliage, and finally the willow and birch leaves. The rest went mostly untouched.
This was the worst gnaw-down at Goodsir since the caterpillar invasion of 1989-90, he said, but already the place is filling out again.
"It's like spring all over," Good said. "The leaves usually come back fairly quickly, within a couple of weeks or so. They are not as thick as the first spring leaves, and it affects the vibrancy of the fall colours if they are second-growth leaves, but the trees are not killed like the mountain pine beetle kills pine trees."
Indirect damage was seen on the flowers.
"I only had one round-leaf white rain orchid come into flower, and normally I'd have 13 or 14," Good said. "I believe it was because the caterpillars took away the cover of leaves above, so more sunlight got down to the ground and put too much sunshine or heat onto those flowers."
Good and Viola both expect a much lower caterpillar population next year as the cycle has reached its peak.
"Nobody likes to see it, but we live in a forest and this is just part of living in the forest," Viola said. "When the ecosystem is doing the things nature intended, it shows that there is probably some overall forest health going on."
Good said the caterpillars peaked a couple of weeks ago at the park, "and then it was like they disappeared overnight." They have now burst from their cocoons as newly hatched moths and can be found against buildings and lights across the area.
