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                                    Grasshoppers: Their Biology, Identification and ManagementSearch small
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ARS Home Plains Area Sidney, Montana Northern Plains Agricultural Research Laboratory Pest Management Research PMRU Docs Grasshoppers: Their Biology, Identification and Management: ID Tools | Apps Field Guide





- NPARL Home
- PMRU Home
- ASRU Home
- Site Highlights
- Outbreak and Survey Info
- ID Tools | Apps
- Grasshopper Management
- IPM Handbook
- USDA Research | Contact Info
- Preface
- Introduction
- External Anatomy
- Species
- Populations
- Life Cycles
- Behavior
- Collections
- Grasslands
- Food Plants
- Glossary
- References

FG Populationsheadline bar **Field Guide to Common Western Grasshoppers:Populations** by Robert E. Pfadt List of Species Fact Sheets (60 Species)  Grasshopper infestations or assemblages consist of the individuals of several species that live together in the same habitat sharing or competing for available food and space. Members of the dominant species outnumber members of other species and may make up more than 50 percent of the assemblage. Occasionally two or three species may become codominants. No evidence has been found for any essential relationship among species that brings them together. The habitat affords the minimum requirements for all the permanent species and ample measure for the abundant. Grass-feeding species of grasshoppers are the most numerous in grasslands. In a northern mixedgrass prairie site 18 miles northwest of Fort Collins, Colorado, a total of 24 species were recorded during an outbreak in 1981 (Table 2). Of the total, 14 were grass feeders, six were mixed feeders, and four were forb feeders. The number of individuals of grass-feeding species made up 85% of the total population. The dominant grasshopper,*Ageneotettix deorum*(Scudder), contributed 52% of the population. A second example of an outbreak population in northern mixedgrass prairie was the assemblage inhabiting a site 15 miles north of Hartville, Wyoming, where 16 species were recorded (Table 2). Nine species were grass feeders, one a mixed feeder, and six were forb feeders. The number of individuals of grass feeding species made up 89% of the population. The dominant grasshopper,*Aulocara elliotti*(Thomas), contributed 74% of the population. Why was*A. deorum*dominant in one mixedgrass prairie site and*A. elliotti*dominant in another? And why was*Cordillacris occipitalis*(Thomas) the second most abundant in one site and entirely missing from the other? Answers to these questions are not available. An hypothesis for the cause of the observed variations in densities was the differences in habitat in conjunction with differences in requirements of the grasshoppers. Although both sites are part of the northern mixedgrass prairie, the soil, slope, and vegetation of each differ significantly. Grasshopper species vary in densities and dominance depending on the soil, vegetation, topography, and use of a habitat. Because of differential effects of weather, parasites, disease, or insecticidal treatments, the densities of grasshopper species inhabiting a rangeland site may change with time. The abundant species, however, tend to retain their dominant status over the years. The composition of grasshopper assemblages is characteristic of various grassland types. A scout working in a western state expects particular species to compose economic infestations in certain areas. Table 3 lists species abundant in several grassland types and in disturbed land (crop borders, fence rows, reversions, roadsides). Because the species composition of grasshopper assemblages infesting particular habitats remains almost the same year after year, a scout is aided in identifying nymphs by knowing the species that were present as adults during past years. Widespread species with high biotic potential, such as*Aulocara elliotti*and*Ageneotettix deorum*, inhabit many grassland types and become abundant members in various assemblages of grasshoppers. In outbreaks on desert grasslands of Arizona and New Mexico, for example,*A. elliotti*is often the dominant species (Table 2), as in many infestations of the northern mixedgrass prairie. **TABLE 2.**Number and density of grasshopper species in mixedgrass prairie and in desert grassland.-
**NUMBER/SQ YD****Mixed grass****Colorado**
**Mixed grass****Wyoming**
**Desert grass****Arizona**Gomphocerinae*Aeropedellus clavatus*
0.2
2.2
N/A*Ageneotettix deorum*
26.3
1.4
0.2*Amphitornus coloradus*
3.9
0.2
0.3*Aulocara elliotti*
2.8
20.7
18.0*Aulocara femoratum*
0.3
N/A
N/A*Boopedon nubilum*
N/A
N/A
0.2*Cordillacris crenulata*
N/A
0.2
N/A*Cordillacris occipitalis*
4.0
N/A
N/A*Eritettix simplex*
+
N/A
0.2*Opeia obscura*
1.6
N/A
N/A*Phlibostroma quadrimaculatum*
0.9
N/A
N/A*Psoloessa delicatula*
0.1
0.3
0.5Oedipodinae*Arphia pseudonietana*
0.02
N/A
N/A*Camnula pellucida*
N/A
0.2
N/A*Hadrotettix trifasciatus*
N/A
0.2
2.5*Mestobregma plattei*
N/A
N/A
0.2***Metator pardalinus*
0.3
2.5
1.8***Spharagemon equale*
0.2
N/A
N/A*Trachyrhachys kiowa*
2.5
N/A
N/A***Trimerotropis pallidipennis*
N/A
N/A
0.9***Xanthippus corallipes*
0.003
0.1
0.2Melanoplinae*Hesperotettix viridis*
0.2
0.2
N/A*Melanoplus bivittatus*
0.1
N/A
N/A*Melanoplus confusus*
0.2
0.2
N/A*Melanoplus cuneatus*
N/A
N/A
20.9*Melanoplus packardii*
0.6
0.2
N/A*Melanoplus gladstoni*
0.5
N/A
N/A*Melanoplus infantilis*
1.2
0.3
N/A*Melanoplus keeleri*
0.3
N/A
N/A*Melanoplus occidentalis*
1.5
1.8
N/A*Melanoplus sanguinipes*
2.8
0.6
6.0Total grasshoppers /sq yd
50.5
31.3
51.9Number species
24
16
13+ indicates species present but not recorded in sampling
 **TABLE 3.**Common species of grasshoppers found in several grassland types, in cold desert shrub, and in disturbed land.**Tallgrass prairie**
*Ageneotettix deorum*
*Melanoplus bivittatus*
*Melanoplus differentialis*
*Melanoplus femurrubrum*
*Orphulella speciosa*
*Phoetaliotes nebrascensis*
*Syrbula admirabilis*
**Bunchgrass prairie**
*Aulocara elliotti*
*Conozoa sulcifrons*
*Cordillacris occipitalis*
*Dissosteira spurcata*
*Melanoplus sanguinipes*
*Oedaleonotus enigma*
*Trimerotropis pallidipennis***Northern mixedgrass prairie**
*Aeropedellus clavatus*
*Ageneotettix deorum*
*Amphitornus coloradus*
*Aulocara elliotti*
*Aulocara femoratum*
*Camnula pellucida*
*Cordillacris occipitalis*
*Encoptolophus costalis*
*Melanoplus infantilis*
*Melanoplus sanguinipes*
*Opeia obscura*
*Phlibostroma quadrimaculatum*
*Psoloessa delicatula*
**Sand prairie**
*Ageneotettix deorum*
*Melanoplus angustipennis*
*Melanoplus flavidus*
*Melanoplus foedus*
*Mermiria bivittata*
*Opeia obscura*
*Phoetaliotes nebrascensis***Shortgrass prairie**
*Cordillacris crenulata*
*Hadrotettix trifasciatus*
*Melanoplus gladstoni*
*Opeia obscura*
*Trachyrhachys aspera*
*Trachyrhachys kiowa***Southern mixedgrass prairie**
*Ageneotettix deorum*
*Amphitornus coloradus*
*Aulocara elliotti*
*Boopedon nubilum*
*Melanoplus sanguinipes*
*Mermiria bivittata*
*Opeia obscura*
*Orphulella speciosa*
*Phlibostroma quadrimaculatum*
**Annual grassland**
*Camnula pellucida*
*Dissosteira pictipennis*
*Dissosteira spurcata*
*Melanoplus devastator*
*Melanoplus marginatus*
*Melanoplus sanguinipes*
*Oedaleonotus enigma***Desert prairie**
*Ageneotettix deorum*
*Amphitornus coloradus*
*Aulocara elliotti*
*Hadrotettix trifasciatus*
*Melanoplus cuneatus*
*Melanoplus sanguinipes*
*Trimerotropis pallidipennis*
**Cold desert shrub**
*Aulocara elliotti*
*Cordillacris occipitalis*
*Dissosteira spurcata*
*Melanoplus rugglesi*
*Oedaleonotus enigma*
*Trimerotropis pallidipennis***Mountain meadows**
*Aeropedellus clavatus*
*Anabrus simplex*
*Camnula pellucida*
*Chorthippus curtipennis*
*Melanoplus alpinus*
*Melanoplus borealis*
*Melanoplus bruneri*
*Melanoplus dawsoni*
*Melanoplus sanguinipes*
*Stenobothrus brunneus*
**Disturbed land (reversions, roadsides, crop borders)**
*Aeoloplides turnbulli*
*Dissosteira carolina*
*Melanoplus angustipennis*
*Melanoplus bivittatus*
*Melanoplus differentialis*
*Melanoplus femurrubrum*
*Melanoplus lakinus*
*Melanoplus packardii*
*Melanoplus sanguinipes*
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