[clickToTweet tweet=”Weather affects everything from the level of soil moisture to the reproduction rates of insect populations,” quote=”Weather affects everything from the level of soil moisture to the reproduction rates of insect populations,”] and different weather trends may submit pests to a whole new set of variables. Now is probably too early to tell the influence that Canada’s dry, mild winter will have on the springtime pest populations, but there are certain patterns in the survival and growth of pest populations we have come to recognize over the years. Here’s what you can expect come spring if our weather stays unseasonably mild and dry.
Overwintering pest populations are directly influenced by winter temperatures, and consequently, warmer-than-normal temperatures cause an increase in the survival rate of many species, especially those overwintering above and below ground. If under normal temperatures, many eggs that weren’t buried deep enough freeze and burst, milder weather means an increased percentage of eggs will hatch, giving birth to pest populations that are greater in numbers and also appear sooner than usual. Encouraged by the generally warmer temperatures, pests that were only found in the southern regions have been reported in northern regions, as well.
For agricultural farmers, winters usually provide a “clean slate” that give farmers a fresh start for the planting season. But with above-the-average temperatures and below-normal snowfall, pests are able to survive, grow, and already start feeding on crops. In case of pests with faster generation times, such as aphids, psyllids, and spider mites, eradication costs can become terribly expensive. For instance, the damage caused by growing populations of flea beetles in canola crops in Canada “is an average defoliation level of 25% or more of the seedling leaf area.
For most pest insects (that are cold-blooded and cannot create their own source of warmth as birds and mammals), normal winter temperatures increase the risk of them freezing to death. Some insects, such as the Monarch butterfly, migrate to regions with warmer temperatures. Ladybugs climb on top of each other to share the heat, while ants and beetles enter a state called diapause in response to adverse environmental conditions. But many species, in lack of overwinter surviving strategies, are likely to freeze to death.
Above-the-average temperatures will not only save many pest species from possible death, it may also cause some of them to appear earlier than expected. Pest control companies have already seen and reported this trend in previous years with similar temperatures. For example, a Tennessee-based pest control company was fielding requests for ant control in late January – significantly earlier than usual. Another large pest control company had reported a 30% increase in requests to treat termite infestations in February, despite the fact that termite swarms do not normally appear until the end of March.
The development of all insects is directly influenced by temperature, including that of beneficial species. For some species, a mild winter could awaken them from their hibernation and cause them to use the fat storages that would’ve guaranteed their survival to spring faster. Since food is not yet readily available outside, these insects are likely to starve to death before food sources become available in the spring.
A perfect example is the honey bee. During warm winters, bees become active, burning calories and eating whatever honey and pollen they have in stores that are supposed to last them until spring. In warmer weather, there is also an increased risk for queens to start laying thousands of eggs per day, giving birth to other thousands of mouths dependent on the food reserves. Meanwhile, with below-normal snow and rain, spring flowers are unlikely to produce the quantities of nectar needed to keep the workers and the young well-fed, and colonies will slowly starve to death as their food runs out.
In agricultural crops, aphids, beetles, weevils, bertha armyworms, flies, grasshoppers, Lygus bugs, tomato psyllids, and numerous others will likely give farmers a hard time, not only because they reproduce at incredibly high rates, but also because some of them transmit pathogens that can destroy the entire plant.
For homeowners who are seeing an increase in wood-dwelling insect populations, steam and heat treatments are the most viable solutions to killing all the insect’s life stages inside the wood. The reason this treatment is so successful is that steam carries a lot of heat, and condensation releases the necessary energy to heat up the wood in which insects reside faster. That means saving time and energy, not to mention the convenience of portability and its reduced environmental effects.
In case of heavy infestations with cockroaches, ants, or termites inside your house, traps and aerosols will sometimes do more harm than good, as they will send them into hiding and cause them to spread their dwelling areas. Calling professional help would probably seem costly in the beginning, but if you think of the long-term benefits, it’s actually a profitable investment.
Many pest control companies provide a free inspection to assess the dimension of the infestation, and the costs will likely be influenced by: the size and type of infestation, the duration of the services (whether one-time or contract), and whether or not you choose additional services (such as repair of the structural damage caused by pests). It’s, however, essential to react as soon as you notice pest damage on your property – once a pest has laid its eggs and formed colonies inside your house, you will have to spend significantly more time and resources to get rid of it.
About the Author
Daniel Mackie, co-owner of Greenleaf Pest Control, is a Toronto pest control expert well-known as an industry go-to guy, an innovator of safe, effective pest control solutions, and is a regular guest on HGTV. Mackie, along with business partner Sandy Costa, were the first pest control professionals in Canada to use detection dogs and thermal remediation for the successful eradication of bed bugs. In his free time, he is an avid gardener.