Tuesday, February 8, 2022

Icy Temperatures: Can it Kill Off Nasty Bugs?




Before this 2021/2022 winter, we’ve had a few decades of warmer-than-average winter temperatures, allowing some insect populations to explode.  So contrarily, this year’s brutal winter should knock them back.  Right?

Invaders from the South

It is true that temperature affects the range of a species.  We know that our warming climate is allowing some insect species to migrate north — for example, deer ticks that carry Lyme Disease (which are not insects per se, but rather arachnids, but I digress). 


When temperatures drop well below -18°C though, many individual insects die. 
The colder the temperature becomes, the fewer survive.

.

How Cold Does It Have To Get?

The actual temperature required to kill off insects varies across species.  The emerald ash borer, for example, can generally withstand temperatures as low as -29°C.  Any colder than that and about half of their population die-off.  At -34°C, even more, are wiped out.  The longer and colder the temperature, the more insects die.

.


.

Read what seed- and plant specialist Barbara Schaefer researched about this winter's effect on nasty insect populations:  
https://gardensbybarby.ca/true-or-false-cold-winters-kill-bugs/

.

<><><><><>

.