Some scourges might not be worth fighting

Jul 22, 2020

A couple of weeks ago there was a bit of an apocalyptic feeling in the air. The oak tree that drops acorns, that sound like gunshots, onto my office roof in the fall most years, was shedding dried, half chewed leaves on the ground at the front door.  This was accompanied by caterpillar droppings, and sometimes in the searing heat of the day, the caterpillars themselves were raining down, landing on my forehead and shoulders.

If the crunch of the dry, chewed up leaves wasn't enough, the grass was crunchier still, as there had been no rain for several weeks, amid sweltering heat and humidity. Meanwhile, the then new spectacle of universal masking in indoor public spaces was eerie, not to mention uncomfortable.

I mentioned this as an aside in a business email that I sent to a friend at the time.

Their response was interesting. It said that the leaves are coming back, the trees are happy, and the world is beautiful. A bit of a Buddhist take on the situation.

Luckily enough, we have had some rain since then and instead of a burnt out July, we are seeing green everywhere again. The garden season is shaping up in spectacular fashion for all the heat loving plants. I'm waiting for the first braggart to talk about how delicious their first tomato is (feel free to write in) and, like everything does over time, the mask wearing is becoming just another thing.

As for those gypsy moths, they are now out, small and brown with antennas. They fly around the trunks and up the branches of trees. Those are the males. The larger females are easy to spot. They are on the trees, and in other places, depositing masses of brown eggs that the male moths fertilize.

There are ways to control these, which, if left alone, could result in a similar, or worse, infestation next year. Or not. Large infestations tend to occur every 7 to 10 years, and the last time it was as bad as this summer seems to have been 31 years ago, in 1989.

According to Ontario Ministry of Natural Resources and Forestry, (MNR-F) the main medium-term impact of the ‘very hungry gypsy moth caterpillars’ on the main host tree species, oaks, is the loss of a season's growth.

“During severe outbreaks, trees and shrubs are completely defoliated over large areas; despite the trees’ ability to produce a new crop of leaves over the summer, the damage causes significant growth loss,” says the gypsy moth page on Ontario.ca.

Individual landowners and lake associations have expressed concerns about the impact of gypsy moths, and there are insecticides available which target them.

One of the reasons for concern, is that in a year like this one, the caterpillars will attack other species, not only deciduous trees but conifers like White Pine, which do not recover as well as deciduous trees do.

A North Frontenac resident, Rick Proctor, who saw this summer’s infestation coming, from the many egg masses that he saw on the trees on his property in the fall, approached the township about the township supporting a spraying program.

He hoped the township would facilitate, not necessarily finance, a program financed by residents.

Council turned him down, for a variety of reasons. While they appreciated the potential for harm from gypsy moths, the consensus was that the potential liability for the township to take on a spraying program was too great.

The township referred Mr. Proctor to the province.

Although the MNR-F, recognises gypsy moths as a problem, another government agency, Parks Ontario, considers them to be more of a nuisance than anything else (see sidebar).

On urban properties, where there are few trees, scraping off the egg masses or applying a water and bleach mixture can deal with the problem, but where there are hundreds or thousands of trees involved, in forested rural areas, the amount of work destroying tens or hundreds of thousands of egg masses is impractical for all but the most diligent of property owners.

That is why there are some who advocate spraying, and others who decide not to address the problem at all, to have faith that the forest will deal with this infestation as it has others in the past, and just as the tent caterpillars, which ravaged fruit trees in 2018 and 2019, seem to be less prevalent this year, the gypsy moths will back off in 2021, or 2022.

This might seem like a cavalier attitude, but in the context of a pandemic, the threat from gypsy moths is not that great.

They downplayed the COVID threat in Sweden, and they now have a death rate of 550 people per million people. We could have cut our lockdown short as they did in the United States, where the death rate is now 430 per million and rising. Instead we were more careful in Canada and our death rate is lower, 239 per million and holding steady, thus far.

To put those numbers into perspective, we can compare them to the disease group that is easily the greatest cause of death in Canada, various forms of cancer. Based on 2019 statistics, 720 Canadians per million die of cancer in a 4-month period.

It is reasonable to assume, given all of the data that is coming in from across the world, that if we had ignored COVID-19 entirely, we would have seen that level of death from the pandemic as well, perhaps more.  

That is not something we wanted to see, and that is why we have done what we have done as regards COVID-19.

So, on the scale of troubles, we can let the gypsy moths do their dance around the base of our trees, and remove the egg masses, or not, or we can address it on our own property if we decide to. 

It is legitimate for municipalities and provinces to leave it to us to decide for ourselves.