There are two to three species of grasshoppers that overwinter in eastern Montana.
Grasshoppers in March and April?
By Elin Kittelmann,
Fallon/Carter County Extension Agent
Grasshoppers in March and April? I have heard of several people seeing grasshoppers in the area right now, but good news they are probably not causing enough damage to be concerned about them.
There are two to three species of grasshoppers that overwinter in eastern Montana. They go in to winter as juveniles and become active as soon as it warms up in the spring. These species hatch in later summer and complete their lifecycle and become adults in the spring. They are found in rangeland and they usually do not do much damage for a few reasons. They are feeding on the spring grass that is able to recover. When they are feeding on rangeland in July in drought conditions is when we see the most damage. Also the overwintering grasshoppers do not get to a high enough population to do a lot of damage. Populations of these overwintering grasshoppers need to reach 10-15 adults per square yard to be of economic concern.
So what species of grasshopper are you seeing? There is a good chance that the species you are seeing now is the red shanked grasshopper, which is one of the few species of grasshopper in MT that overwinters as immature nymphs. The redshanked grasshopper inhabits the grassland and shrub-grass communities. They will become active on warm days and feeds on almost exclusively grass. In the spring both the nymphs and the adults feed heavily on the green, early growth of cool-season plants such as western wheatgrass, needle-and-thread, junegrass, and downy brome a characteristic of this species of grasshopper is that the inside of the rear legs are red. Populations never tend to get high enough to do damage, so treatment is not necessary. If you are seeing more than 10-15 per square foot, please let me know and we can visit future about possible control options. Since this is not a common time to treat for grasshoppers we would have to come up with specific recommendations.
Are these overwintering grasshoppers any indication of the grasshopper populations we will have this summer? No, the abundance of one species will not be a good predictor of another, particular since these grasshoppers are cold adapted. They may even occur as far north as Alaska.
If you have other questions about grasshoppers or have an insect you are interested in getting identification and more information on find contact us at your Fallon/Carter Extension Office 406-778-7110 or firstname.lastname@example.org.