Editorial: Get the jump on these common pests
March 31, 2023 By Derek Clouthier
Pests and disease is the main theme of this April issue, and it was interesting looking online at what some of the most common pests farmers in Alberta and Western Canada have to deal with in their crops. A few I have heard of and many I have not, but as someone who does not come from an agricultural background, it is eye-opening to learn how damaging the common grasshopper can be. As a kid, I used to play with grasshoppers. It was fun to have them leap from my hand and try to catch the jumpy little critters as they tried to get away. I used to think they pooed in your hand when you caught them, but now I’ve learned they spit a brown liquid to defend themselves. Reading about this gross defense mechanism, it was fascinating that some people say they spit tobacco juice, as apparently grasshoppers are historically associated with tobacco crops.
But, despite how enjoyable these skittish little insects are to kids – which are seemingly one of the most ancient living groups of chewing herbivore insects on Earth, around before the dinosaurs – the “chewing” part is what makes them so devastating to crops.
Grasshoppers, which are essentially locusts, certainly aren’t territorial, and when you have one, it’s likely you have many. Considering a grasshopper eats about half its bodyweight (30 to 100 mg) in plants every day, tens of thousands of these pests can cause significant damage to crops. A moderate infestation, according to the Alberta government, is 10 grasshoppers per square metre, and that amount can consume up to 60 per cent of available forage. Loving hot, dry weather, certain areas of Western Canada can be a magnet to grasshoppers, particularly southern Alberta. Cereal grains are most at risk, but lentils and canola can also be on a grasshopper’s menu.
In a field, grasshoppers numbering greater than 13 per square metre means control measures are needed. Grasshoppers tend to stay away from oats and peas, though they will feed on those crops at times. A study done in Alberta on grasshopper trends indicates the number of grasshoppers in the southern and eastern areas of the province have been increasing since 2021, and the trend is expected to continue in 2023. The Lethbridge region, particularly to the southeast and north, are where high numbers of grasshoppers have been noticed. Saskatchewan is a similar story, where numbers have been increasing over the past couple of years, with significant populations reported in the southcentral, southwestern and southeastern regions. Manitoba was a bit less severe, as most of the province indicated light to moderate numbers of grasshoppers, with some high numbers in the central region.
Though most who are not in agriculture tend to relish those hot, sunny summer days, it is always interesting to learn more about what that means for farmers. There is a fine balance between too much and too little rain, warm weather, direct sun, cool or warm nights, and I can only guess what measures must be taken to ensure a quality crop.
One thing is for sure: my dog will do everything she can to help lower the grasshopper population. She hates those little pesky buggers.