Grasshoppers are difficult to control but their impact can be minimized through preventative management over the long term using non-chemical strategies. These include cultural controls like fall tillage to destroy eggs, trap cropping to concentrate grasshoppers, and encouraging natural predators. Biological controls such as the protozoan Nosema locustae and fungus Beauveria bassiana can be used against nymphs and adults. Physical barriers and traps can also help reduce grasshopper populations. Maintaining farm biodiversity is key to preventing major outbreaks.
2. be scheduled accordingly. Your local or state and sanitation procedures that reduce winter soil
Extension service can help identify the grasshop- cover may not be compatible with the goals of
per species and provide information on its life sustainable farming and should be used sparingly.
cycle.
TRAP CROPS
W EATHER Trap crops are small plantings established
Grasshopper outbreaks are determined by a within or next to the main crop to draw the pests
complex interaction of several factors, of which away and concentrate their populations where
weather is the most important (3). Warm and they can be destroyed. In spring, tilling all plant
dry spring conditions encourage nymphal growth. matter will probably not work because nymphs
An early spring followed by cloudy, damp mobile enough to search for food will simply
weather encourages diseases that sicken and kill move to adjacent crops. Strips of vegetation left
hoppers. A long, hot summer ensures a plenti- untilled will concentrate their populations and
ful food supply and encourages early maturity make insecticide treatments, whether synthetic
of grasshoppers and a long egg-laying period. or organic, more efficient.
On the other hand, a cool summer and early fall In summer, when the surrounding rangeland
slows down grasshopper maturity and reduces vegetation begins to dry up, trap crops act as a
time for laying eggs. barrier to migrating grasshoppers (5). In the case
of a market garden, an irrigated “greenbelt” along
CULTURAL CONTROLS the perimeter acts as a trap crop for migrating
grasshoppers when the surrounding vegetation
The long-term control of grasshoppers is pos- begins to dry up in late summer. The annual
sible through the use of cultural practices like kochia (Kochia scoparia) is attractive to the grass-
tillage, fall clean-up, trap cropping, early seed- hopper and reportedly works well as a shelter
ing, and early harvest. The use of these tools belt (6). Grasshoppers dislike cilantro, and some
may be guided effectively by fall egg counts and organic growers suggest planting a wide barrier
regular scouting to identify hatching locations. of the crop for protection (7).
Cultural measures, in conjunction with biologi-
cal controls and practices that increase farm
biodiversity, provide good sustainable control in
P REDATORS
the long run. Natural predators and parasites rank next in
Grasshoppers breed and grow in weedy, un- importance to weather in keeping grasshopper
disturbed areas like roadside ditches, fence rows, populations in check. In addition to IPM pro-
untilled pastures, and in crops that stay around grams that reduce pesticide usage, actions that
for more than a single growing season. increase the numbers of beneficial insects and
A survey of the area after the eggs hatch helps other organisms in the agro-ecosystem must be
to ascertain where populations are developing. encouraged. For additional information, see
Optimal control is possible when the insects are ATTRA’s publications Farmscaping to Enhance Bio-
still immature and restricted to their breeding logical Control and Biointensive Integrated Pest Man-
areas. Growers may use organically approved agement. Crop rotation and other organic prac-
botanical products like sabadilla or pyrethrin to tices that increase bio-diversity offer a certain
knock down nymphs in the first or second instar. degree of protection against pests. Grasshop-
TILLAGE
pers are drawn to monocultures and dislike ni-
trogen-fixing crops like peas and sweet clover
(8). Rotation, cover cropping, and other prac-
Tillage in late summer discourages females tices that promote bio-diversity make farm habi-
from laying eggs in the ground. It also destroys tats more attractive to the host of natural preda-
eggs by exposing them to the weather, preda- tors and parasites that control localized grass-
tors, and parasites. Spring tillage is effective pri- hopper infestations.
marily because it eliminates food sources for the Domesticated poultry like chickens, turkeys,
newly hatched nymphs (4). However, fall tillage guinea fowl, geese, and ducks are good for keep-
PAGE 2 //GRASSHOPPER MANAGEMENT
3. ing grasshopper populations in check, although Fraser University at http://www.sfu.ca/bisc/
they tend to damage the plants in the garden too. bisc-842/michael/web_page/antifeed.htm.
One way to handle this is to confine the birds to
the greenbelt. Another is to enclose them in wire
fencing along the perimeter so that they can prey
PHYSICAL BARRIERS AND TRAPS
on visiting grasshoppers while staying out of the References to mechanical trapping of grass-
crop. hoppers in the literature date as far back as 1877.
An early incarnation of the ‘hopper dozer’ was a
BIOLOGICAL CONTROLS metal scoop coated with tar that was dragged
across the fields to trap grasshoppers (11). A
A well-known biological control for grasshop- more contemporary, low-tech version of the hop-
pers is Nosema locustae, a naturally occurring pro- per dozer consists of a tractor that has a long
tozoan that causes disease and death in crickets narrow trough hooked on the front end. The
and grasshoppers. Spores of the parasite are trough has a 3’ screen in the back and is filled
impregnated into wheat bran flakes and applied with dry ice or water laced with kerosene. When
on the field. It takes one to three weeks for the the trough is pushed across the field, the hop-
grasshoppers to be infected. Following inges- pers jump up and slap against the screen and fall
tion, the spore ruptures and activates the dis- in to the trough where they are chilled by the dry
ease in the grasshopper. Infected individuals are ice or drown in the water (12). The hopper dozer
lethargic and slow, making them easy prey for only eases pest pressure; it does not control
birds. Nosema locustae is not toxic to birds, ani- grasshoppers, nor can it prevent additional inva-
mals, or other insects. sions from surrounding areas.
Growers are advised to locate spring hatch- Another tool called the hopper whopper was
ing areas. Bait broadcast over these locations will built by Vern Erickson (13), a Minnesota farmer,
sicken and kill the nymphs. Nosema is effective to reduce grasshopper populations on his CRP
against adults too but most effective against the acreage. An article titled “Hopper Whopper
second and third instars. Reports on the success Keeps CRP Acres Grasshopper-Free,” published
of N. locustae are mixed. It is not a good “res- in the magazine Farm Show, has the following
cue” treatment and will not result in instant adult description (14):
mortality. According to Jerome Onsager, one of
the first Nosema researchers at the USDA Range- Erickson built his “hopper whopper” by sus-
land Insect Laboratory in Bozeman, Montana, pending six rows of tires from a 14-ft. long, 4 by
Nosema was developed as a long-term manage- 4 in. toolbar that attaches to the front-end loader
ment tool, not to provide instant control. Onsager on his…tractor. A pair of brackets welded to the
says that Nosema research has been most success- top of the bar fasten with pins to the loader
ful on rangeland. Information on the USDA’s arms.
grasshopper IPM project is available from Re-
search Entomologists Jerry Onsager or David There are five tires per row. The wheel rims of
Branson (9). all five tires in each stack are welded together,
The Maxwell National Wildlife Refuge in and the top rim on each row is bolted to an old
northeastern New Mexico has reported good suc- carwheel hub. The hub’s spindle is welded to the
cess with Nosema as part of an overall effort to- steel bar, allowing each stack of tires to spin
ward sustainable agriculture. For additional in- freely. An orbit motor mounted on the steel bar
formation, contact Patricia Hoban, Manager (10). and connected to a gearbox (salvaged from the
The fungus Beauveria bassiana is yet another straw spreader off a…combine) drives a roller
biopesticide registered for grasshopper control. chain that’s wrapped around a top tire on the
Suppliers of the product are listed at the end of third stack in from one end. This “drive” tire
this publication. causes all of the other tires to rotate, with each
Neem has not shown much success as an anti- pair of tires turning inward. Chains hanging
feedant against grasshopper species in the United from a rod out in front of the tires drag through
States but has promise as a growth regulator. A the grass and cause grasshoppers to jump up so
summary of this subject is available on an Internet they can be caught and crushed by the rotating
site maintained by Michael Bomford of Simon tires.
//GRASSHOPPER MANAGEMENT PAGE 3
4. Erickson uses the rig early in the season, when 6) Rateaver, Bargyla, and Gylver. 1993. The
the nymphs are still young and cannot fly out of Organic Method Primer Update. The
the way. Rateavers, San Diego, CA. p. 89.
During particularly bad infestations, market
7) Cooper, S. 1994. Tales from the grass-
gardeners may use row covers and protective
hopper wars. The Farm Connection.
screens to temporarily exclude pests from spe-
Volume 2, No. 6. p. 2.
cific plants or an entire garden. Suppliers of row
covers are listed at the end of this publication. 8) Groenen, Wilma. 1992. Living with
grasshoppers. Synergy. Winter. p. 22-26.
C ONCLUSION 9) Jerome Onsager/ David Branson
1500 Northcentral Avenue
A healthy and diverse farm environment usu-
Sydney, MT 59270
ally discourages the build-up of a lasting pest
406-482-2020
infestation. Improving the bio-diversity on the
farm will be the single most important step to 10) Maxwell NWR
take. Cultural practices that increase organic P.O. Box 276
matter in the soil and make habitat more attrac- Maxwell, NM 87728
tive to predators improve the vigor and resis- Phone and FAX: 505-375-2331
tance of the farm. Some cultural practices such 11) Editor. 1877. St. Paul Pioneer Press
as fall tillage may be inconsistent with long-term Editorial. May 31. Newspaper Microfilms
sustainable farming. These practices should be Collections State Archives, Minnesota
viewed as transitional or ‘rescues’ and phased Historical Society. No page #.
out over time.
12) Rateaver, Bargyla, and Gylver. 1993. The
R E.ERENCES Organic Method Primer Update. The
Rateavers, San Diego, CA. p. 328.
1) http://ipm.ncsu.edu/AG271/forages/ 13) Vern Erickson
grasshoppers.html Route 1, Box 205
Pest management information from the Fertile, MN 56540
National IPM Network, a cooperative 218-945-6617
effort of the NC Coop Extension Service 14) Anon. Hopper whopper keeps CRP acres
and the NSF Center for IPM located at grasshopper-free. Farm Show. Vol. 15(5).
North Carolina State University. p. 36. A copy of the article may be ob-
2) Anon. 1992. Grasshoppers a recurrent tained from:
problem with no perfect solutions. Grow- Farm Show
ing for Market. June. p. 9. 20088 Kenwood Trail
3) Gregoire, Terry (ed.) ProCrop 1998. Area P.O. Box 1029
Extension Specialist/Cropping Systems, Lakeville, MN 55044
Devils Lake, ND. http:// 800-834-9665
www.ag.ndsu.nodak.edu/aginfo/
procrop/ins/grassp05.htm
INTERNET RESOURCES
4) http://www.agric.gov.ab.ca/pests/
insects/ 62010120.html#management http://www.ianr.unl.edu/pubs/insects/
nf328.htm
Grasshoppers — Clear-winged Camnula Hagen, A., J.B. Campbell, D.L. Keith. A Guide
pellucida. Information maintained by Jim to Grasshopper Control in Cropland,
Jones. Revised December 6, 1995. NebGuide, Cooperative Extension, Univer-
5) University of California Statewide IPM sity of Nebraska-Lincoln. #G86-791-A.
Project (ed.) UC Pest Management Guide-
lines, University of California Statewide
IPM Project. Updated December 1997.
PAGE 4 //GRASSHOPPER MANAGEMENT
5. http://www.nysaes.cornell.edu/ent/biocontrol/ IFM
pathogens/entomophaga_grylli.html 1422 N. Miller Street Ste. 8
Weeden, Shelton, and Hoffman (eds.) Bio- Wenatchee, WA 98801
logical Control: A Guide to Natural Enemies 800-332-3179; FAX 509-662-6594
in North America. Cornell University.
M&R Durango, Inc.
http://www.aes.purdue.edu/AgAnswrs/1995/ P.O. Box 886
7-14Treat_Grasshoppers.html Bayfield, CO 81122
Ag Answers, a collaborative effort of Purdue 800-526-4075; FAX 970-259-3857
University and The Ohio State University.
Gardens Alive
http://www.ext.colostate.edu/pubs/insects/ 5100 Schenley Place
05536.html Lawrenceburg, IN 47025
Granshaw, W.S., and J.L. Capinera. Grass- 812-537-8650; FAX 812-537-5108
hopper Control. Colorado State University
Cooperative Extension. SUPPLIERS O. BEAUVERIA
http://128.227.103.60/txt/fairs/50667 BASSIANA
Florida Agricultural Information Retrieval
System. Troy Biosciences, Inc.
2620 N., 37th Drive
http://www.ag.ndsu.nodak.edu/aginfo/ Phoenix. AZ 85009
procrop/ins/grassp05.htm 800-448-2843, 602-233-9047; FAX 602-254-7989
Pest management information from the Na-
tional IPM Network, a cooperative effort of Hydro-Gardens, Inc.
the NC Coop Extension Service and the NSF P.O. Box 25845
Center for IPM located at North Carolina State Colorado Springs, CO 80936
University. 719-495-2266 or 888-693-0578; FAX 719-495-2266
or 800-694-6362
http://ndsuext.nodak.edu/extnews/procrop/
ins/grassp05.htm The Green Spot, Ltd.
Gregoire, Terry (ed.) ProCrop 1998. Area Dept. of Bio-Ingenuity
Extension Specialist, Crop Production, Dev- 93 Priest Road
ils Lake, ND. Nottingham, NH 03290
603-942-8925
http://www.agric.gov.ab.ca/pests/insects/
62010120. html#management
Alberta Agriculture, Food and Rural Devel-
ROW COVERS
opment American Agrifabrics
1282 Old Alpharetta Road
SUPPLIERS O. NOSEMA LOCUSTAE Alpharetta, GA 30202
800-565-5151; 803-772-3222
Planet Natural (formerly Bozeman Bio-Tech)
1612 Gold Ave Gardens Alive
Bozeman, MT 59715 5100 Schenley Place
800-289-6656 Lawrenceburg, IN 47025
Fax: 406-587-0223 812-537-8650; FAX 812-537-5108
Harmony Farm Supply & Nursery Harmony Farm Supply & Nursery
3244 Hwy. 116 3244 Hwy. 116
N. Sebastopol, CA 95472 N. Sebastopol, CA 95472
707-823-9125; FAX: 707-823-1734 707-823-9125; FAX: 707-823-1734
//GRASSHOPPER MANAGEMENT PAGE 5
6. Peaceful Valley Farm Supply
PO Box 2209
125 Springhill Blvd.
Grass Valley, CA 95945
530-272-4769; 1-888-784-1722
Original publication by Radhika Bala
Updated by Nancy Matheson
NCAT Agriculture Specialist
September 2003
IP145/111
The electronic version of Grasshopper Management is
located at:
HTML
http://attra.ncat.org/attra-pub/grasshopper.html
PDF
http://attra.ncat.org/attra-pub/PDF/grasshopper.pdf
PAGE 6 //GRASSHOPPER MANAGEMENT