Idaho

Idaho
Idaho is within:
Country:	United States of America

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Idaho is a mountainous state in the northwestern United States characterized by diverse ecosystems, including alpine forests, high desert plains, and extensive river systems. Its ecology supports a wide range of wildlife and vegetation, from dense coniferous forests in the north to sagebrush steppe in the south. Agriculture plays a major role in the state’s economy, particularly in the southern regions. Periodic grasshopper outbreaks, especially in southern Idaho, pose a threat to crops and rangelands, prompting coordinated pest management efforts by state and federal agencies.

State ecology

Idaho is both geographically and ecologically diverse, with two major landforms: a mountainous north-south region and the east-west Snake River Plains, marked by rolling hills and lava outcrops. With nearly 12,000 feet of elevation range, climate and vegetation vary more by altitude than latitude. Major rivers like the Snake, Clearwater, and Bear shape the state’s drainage. Idaho contains 10 established biotic zones, with one additional zone suggested in this study. Many grasshopper species favor the arid sagebrush-grass zone, while most banded-wing types occur across three main ecological zones, often overlapping in valleys and along mountain ridges.

Highlighted species from Idaho

Species	Official common name	Image
Acrolophitus pulchellus	Idaho point-headed grasshopper
Aeoloplides turnbulli	Turnbull’s grasshopper
Aeropedellus clavatus	Club-horned grasshopper
Ageneotettix deorum	White-whiskered grasshopper
Amphitornus coloradus	Striped grasshopper
Anabrus simplex	Mormon cricket
Arphia conspersa	Speckled rangeland grasshopper
Arphia pseudo-nietana	Red-winged grasshopper
Aulocara elliotti	Big-headed grasshopper
Aulocara femoratum	White cross grasshopper
Camnula pellucida	Clear-winged grasshopper
Chortophaga viridifasciata	Northern green-striped grasshopper
Cordillacris occipitalis	Western spotted-winged grasshopper
Derotmema haydenii	Hayden's grasshopper
Dissosteira carolina	Carolina grasshopper
Encoptolophus costalis	Dusky grasshopper
Eritettix simplex	Velvet-striped grasshopper
Hadrotettix trifasciatus	Threebanded grasshopper
Hesperotettix viridis	Meadow purple-striped grasshopper
Melanoplus alpinus	Alpine grasshopper
Melanoplus angustipennis	Narrow-winged sand grasshopper
Melanoplus bivittatus	Two-striped grasshopper
Melanoplus bowditchi	Sagebrush grasshopper
Melanoplus bruneri	Bruner spur-throated grasshopper
Melanoplus confusus	Pasture grasshopper
Melanoplus dawsoni	Dawson's spur-throat grasshopper
Melanoplus differentialis	Differential grasshopper
Melanoplus differentialis	Differential grasshopper
Melanoplus femurrubrum	Red-legged grasshopper
Melanoplus foedus	Striped sand grasshopper
Melanoplus gladstoni	Gladston grasshopper
Melanoplus infantilis	Little spur-throated grasshopper
Melanoplus keeleri	Keeler grasshopper
Melanoplus kennicottii	Kennicott's spur-throat grasshopper
Melanoplus occidentalis	Occidental grasshopper
Melanoplus packardii	Packard grasshopper
Melanoplus rugglesi	Nevada sage grasshopper
Melanoplus sanguinipes	Migratory grasshopper
Mermiria bivittata	Two-striped mermiria grasshopper
Metator pardalinus	Blue-legged grasshopper
Oedaleonotus enigma	Valley grasshopper
Phlibostroma quadrimaculatum	Four-spotted grasshopper	File:File:Fld-Phqu2N01-03.jpg
Phoetaliotes nebrascensis	Large-headed grasshopper
Pseudochorthippus curtipennis	Marsh meadow grasshopper
Psoloessa delicatula	Brown-spotted range grasshopper
Spharagemon collare	Mottled sand grasshopper
Spharagemon equale	Say's grasshopper
Trachyrhachys kiowa	Kiowa grasshopper
Trimerotropis pallidipennis	Pallid-winged grasshopper
Xanthippus corallipes	Red-shanked grasshopper

Species of management concern

Southern Idaho is home to more than 40 grasshopper species, but only a handful regularly reach pest status. The most problematic belong to the spur-throated subfamily (Melanoplinae), which includes the two-striped grasshopper (Melanoplus bivittatus), the red-legged grasshopper (Melanoplus femurrubrum), the differential grasshopper (Melanoplus differentialis), and especially the migratory grasshopper (Melanoplus sanguinipes), the region’s most damaging species. M. sanguinipes thrives in a wide range of habitats, feeds on many grasses and forbs, and can rapidly reach outbreak levels under favorable conditions. It often migrates to irrigated crops when rangeland vegetation dries during summer droughts. The clear-winged grasshopper (Camnula pellucida) is also capable of becoming an agricultural pest.

Some species are more specialized in their diets and habitats. The Ashy spur-throat grasshopper (Melanoplus cinereus) feeds almost exclusively on sagebrush and is restricted to areas where it grows, while Hesperotettix viridis primarily consumes rabbitbrush (Chrysothamnus spp.). Another notable species, the valley grasshopper (Oedaleonotus enigma), can also reach high densities and shift its diet seasonally—from forbs and cheatgrass in spring to sagebrush in summer. However, because a large portion of its population is flightless, it poses less of a threat to cropland than M. sanguinipes.

The Mormon cricket (Anabrus simplex), though not a true grasshopper, is another major pest in the region. This large, flightless katydid forms migratory bands that can devastate vegetation over wide areas.

Most Oedipodinae grasshoppers in Idaho complete a one-year life cycle, laying eggs in late summer that hatch the following spring. Development from nymph to adult takes about 35 days, depending on weather and food availability. Some species, like the speckled rangeland grasshopper (Arphia conspersa) and certain Xanthippus subspecies, require two years, overwintering first as eggs and later as partially grown nymphs. Egg-laying typically occurs in bare soil, though C. pellucida often deposits eggs in or near grassy clumps, suggesting other environmental cues may guide site selection.

View U.S. Grasshopper Forecast Hazard Maps

Grasshopper management

Grasshopper and Mormon cricket populations are present in certain parts of Idaho almost every year. The Idaho State Department of Agriculture monitors these species closely and provides support to landowners through its Grasshopper and Mormon Cricket Control Program. The program offers support to agricultural producers by providing pest management information and insecticide bait. Eligible landowners—those managing at least five acres of agricultural land with infestations meeting specific thresholds—can receive assistance Invasive Species of Idaho. The U.S. Department of Agriculture's Animal and Plant Health Inspection Service (APHIS) also plays a role by conducting surveys and implementing suppression projects, ensuring environmental assessments indicate no significant impact from control measures.

Monitoring grasshoppers in late summer and early fall helps forecast potential problem areas for the following year. Spring surveys of young nymphs can reveal where eggs were heavily deposited, allowing for targeted treatment of those hotspots. Grasshopper control is most effective when focused early, targeting young nymphs near hatch sites. Managing large areas is important since grasshoppers are highly mobile. Natural predators and pathogens help keep populations in check, especially when broad insecticide use is limited. Chemical sprays and baits can be effective tools, particularly in the spring, with partial coverage often sufficient.

Featured resources

• 
  Grasshopper & Mormon Cricket Control Insecticide Reimbursement Handbook
• 
  Grasshopper & Mormon Cricket Control Ag Producer Assistance Handbook

Select photos from Idaho

No images found for this query—should be coming soon!

Outbreaks

​In 2023, the Idaho State Department of Agriculture designated outbreaks in Cassia, Oneida, Power, and Franklin counties. The infestations led to over 182 assistance requests from landowners, marking a 62% increase from the previous year.

Organizations

Organization name	Acronym	Website	Type	Focus	Focus keywords
Idaho State Department of Agriculture		https://agri.idaho.gov/main/	Government	Education, Management	Emergency assistance
National Grasshopper Management Board	NGMB	https://www.sites.google.com/site/ngmborg/home	Non-profit Organization	Governance, Management	Coordination, Natural sciences
Rangeland Grasshopper and Mormon Cricket Suppression Program at the United States Department of Agriculture		https://www.aphis.usda.gov/aphis/ourfocus/planthealth/plant-pest-and-disease-programs/pests-and-diseases/grasshopper-mormon-cricket/ct_grasshopper_mormon_cricket	Government	Management, Education, Information Hub	Control, Forecasting, Monitoring
University of Idaho Extension		https://www.uidaho.edu/extension	University	Education, Research, Monitoring, Management	Extension

Resources

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