Suppression of grasshoppers in the Great Plains through grazing management
Author
Onsager, J. A.Issue Date
2000-11-01Keywords
Melanoplus sanguinipesopeia obscura
encoptolophus costalis
melanoplus gladstoni
Acrididae
heat sums
life cycle
insect control
population density
continuous grazing
Agropyron cristatum
mortality
rain
rotational grazing
prairies
biomass
range management
canopy
North Dakota
grasshopper management
twice-over grazing system
rotational grazing
Menaloplus sanguinipes
Metadata
Show full item recordCitation
Onsager, J. A. (2000). Suppression of grasshoppers in the Great Plains through grazing management. Journal of Range Management, 53(6), 592-602.Publisher
Society for Range ManagementJournal
Journal of Range ManagementAdditional Links
https://rangelands.org/Abstract
It was hypothesized that grazing management could mitigate grasshopper outbreaks on native rangeland in the northern Great Plains. Key practices would require deliberate variation in timing and intensity of grazing events, preservation of canopy during critical periods of grasshopper development, and reductions in areas of bare soil. The twice-over rotational grazing system appeared compatible with those requirements. Grasshopper population trends were monitored during 1993–1995 and 1997–1998 on commercial native rangeland under twice-over rotational grazing vs traditional season-long grazing. A ubiquitous pest grasshopper, Melanoplus sanguinipes (Fabricius), occurred at every sample site during each year in numbers sufficient to provide life history parameters for comparison between treatments. Under rotational grazing, the nymphs developed significantly slower and their stage-specific survival rates were significantly lower and less variable. Consequently, significantly fewer adults were produced signifi-cantly later in the season under rotational grazing.Seasonal presence of all grasshopper species combined averaged 3.3X higher under season-long grazing than under rotation-al grazing. Local outbreaks that generated 18 and 27 adult grasshoppers per m2 under season-long grazing in 1997 and 1998, respectively, did not occur under rotational grazing. The outbreaks consumed 91% and 168%, respectively, as much forage as had been allocated for livestock, as opposed to 10% and 23%, respectively, under rotational grazing. Of 9 important grasshopper species, none were significantly more abundant at rotational sites than at season-long sites. Three species that were primary contributors to outbreaks under season-long grazing remained innocuous under rotational grazing. It therefore appears that outbreak suppression through grazing management is feasible in the northern Great Plains.Type
textArticle
Language
enISSN
0022-409Xae974a485f413a2113503eed53cd6c53
10.2307/4003152
Scopus Count
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