Abandon hope for a bug-free Minnesota summer
Put aside any wishful thinking that this year’s extended winter will reduce the number of bugs that bite, suck your blood or devour the leaves on trees.
“I don’t think the late season and snow cover is going to kill any of them,” said retired teacher and area naturalist Larry Weber while talking about mosquitoes, ticks and blackflies. “I think they will all make it; it’s just that they will be coming a little bit later.”
The story is the same for forest pests such as army worms.
“Most of the stuff we have is pretty well adapted” to winter, said Mike Albers, a forest health specialist with the Minnesota Department of Natural Resources’ Division of Forestry. “I don’t think going late like this will have any significant impact” in reducing pest numbers.
That might not have been the case had the weather warmed up — bringing the bugs out — and then turned cold again. But that’s not what has happened this year.
“For the most part, those insects just sit there and wait until they get that warmer weather,” Albers said. “We haven’t had enough warm weather to get any of them thinking of coming out.”
Many insect species pass winters as eggs or immatures. Blackflies, for example, pass the winter as immatures in moving water. Among the blood suckers, “blackflies will likely be the least affected,” Weber said. “Like everything, their season may be delayed, but I would look for them in May.”
The appearance of mosquitoes will also be delayed, but in the long run they will probably thrive this year.
“All this snow will give us a tremendous amount of melt water” providing breeding pools for the bloodsuckers, Weber said.
Ticks largely survive winter as immatures in leaf litter. Snow helps them survive by protecting them from bitter-cold temperatures of midwinter.
Both deer and wood ticks are typically out by now.
“This is their season,” Weber said. “However, they are tough critters and I think they will survive. What may come out of this is that we will have a later deer tick and wood tick season, but I still expect them to come.”
That is Albers’ belief about the insects that attack our forests. Army worms pass the winter as larvae in egg masses.
“They are just sitting there, waiting until it warms up so they can start coming out,” he said. “They are pretty well-adapted to come out when the aspen leaves start coming out.”
The numbers of army worms are climbing. In 2011 the pest defoliated about 60,000 acres throughout Minnesota; last year they stripped about 250,000 acres.
Most of the damage was in small pockets scattered across the state, although “we had a couple areas — one near Tower, the other in Cass County — where we had thousands of acres of complete defoliation,” Albers said.
He expects the Northland will see more army worms this year, although nowhere near peak numbers. In 2001 and 2002 the insect defoliated between 7.5 million and 8 million acres of forests.
Winter’s repeated encores may slow population growth of some species — such as bark beetles — that can have several generations of reproduction in a year.
Looking beyond bugs, Weber was concerned early in winter that a lack of snow would claim some frogs and snakes, but then it snowed. And snowed. And snowed. It’s too early to tell if the species took a hit over the winter, he said.
Weber saw migrating yellow rump warblers and hermit thrushes Monday — largely on time. And to the south of us, large numbers of birds are staged, just waiting for a change in the weather to resume their flights north.
“By the time we get to this time of April and see this much snow it’s easy to think, ‘Oh, spring has been canceled this year,’ ” he said. “But no, stick with it; it’s going to happen.”
Article written by Steve Kuchera of the Forum News Service