It has been such a cold Winter. We’re not sure we can remember ever having so many consecutive days of -20 °C and below. While we might prefer our winters a little less harsh, there might be an upside to all of this seasonal inhospitableness: Less caterpillars!
Think back to last summer, if you will. As we were living in the midst of a global pandemic, trying to make the best of a difficult situation, we were presented with yet another curveball: A caterpillar infestation of epic proportions. Really, what we experienced last year often felt like something out of a horror movie.
These nasty little pests made our hiking excursions angst ridden, our outdoor visits messy with poop raining from the trees (cover your coffee!)….even sitting on the dock was almost unbearable at times, as we were constantly bombarded by multitudes of caterpillars dangling from shoreline trees.
At our place, the devastation was painfully obvious when looking up at bare-to-the-branches oaks and maples. It looked like mid-winter in July, the ground littered with chewed up leaf confetti.
LDD moths and their caterpillars have commonly been know as the “gypsy moth” (not so nice), but have recently have been renamed to “spongy moths” for the egg masses they leave on the trees. They strip trees bare from their leaves and cause a nasty rash on people’s skin, as their hairs are an irritant. A single caterpillar is able to eat up to one square meter of leaves in one season……which is surprising considering how small they are! No wonder there was poop everywhere!!
Although trees affected by LDD infestations look really bad, this invasive species is a defoliate, not a killer. Defoliation in Ontario increased from 586,385 hectares in 2020 to almost 1.8 million hectares in 2021. Luckily, most trees survive infestations as long as they are healthy and not facing drought conditions. The trees on our property actually produced a second flush of leaves in August, much to our surprise and relief.
All of that drama and destruction left many of us wondering, what does the Summer 2022 have in store for us from an LDD perspective?
Well, this species tends to go through a boom and crash cycle every 10-15 years. Viruses and fungal diseases are usually a cause in the population decrease, but there is another factor that can arrest an infestation dead in its tracks. You guessed it…….Extreme cold weather! From Ontario.ca: Extended days of extreme cold (-20 degrees celsius) may kill overwintering larvae in exposed egg masses.
So although 2022 has delivered us one of the coldest winters we can remember, and that may not be everyone's preference, most would gladly take it over another caterpillar catastrophe.