THREE COMMON KENTUCKY GRASSHOPPERS
AND THEIR NATURAL ENEMIES
By D. Shanklin, L. Townsend, R. Bessin, Extension Specialists
University of Kentucky College of Agriculture
Grasshoppers are familiar to most people; their large "jumping legs" easily identify them.
Worldwide, grasshoppers are some of the most
serious agricultural pests, most often due to their
direct feeding on the harvestable portion of the crop.
However, in the United States, pest outbreaks occur
most often in the western U. S., or following drought
in other, generally wetter regions, including
Grasshoppers are insects in the Order Orthoptera.
They have an incomplete life cycle, i.e. there are only
three stages in its life cycle: the egg, the nymph, and the
adult. The nymphal stage can be distinguished from the adult by the nature of the wings. Nymphs have nonfunctional wing pads whereas adults have fully developed, functional wings. The adult wings are folded over the back when not in use.
Most adults have two pairs of wings: parchment-like
front wings, and membraneous, fan-like hind wings.
Mouthparts are the typical chewing type, and a pair
of short cerci (appendages) are present at the end of
There are 3 species of grasshoppers that are the most
common in Kentucky: the redlegged, the two-striped,
and the differential grasshopper.
Ranging in size
from 1/2 to 1-3/4 inches, all three common species are
from the Family Acrididae. They all have threadlike
antennae that are shorter than the body. The
ovipositor of females is short and the tarsi (feet) are
three-segmented. Acrididae generally have a median
spine or tubercle (raised area) on the prosternum (area
behind the head), and most have a vertical face or
In Kentucky, the impact grasshoppers have on the
health and economics of the crops grown in
the state varies with the crop, and within the season.
Generally, in Kentucky, small grains such as wheat
are harvested in the early summer long before
grasshoppers are large enough to do much damage.
In the fall, grasshoppers have disappeared before the
small grains emerge. However, corn and soybeans
may have localized problems with this pest.
be it conventional, minimum, or no-till, is an
important factor. In conventional tillage situations,
grasshoppers are usually not a problem until
midsummer, and usually occur along field edges.
In no-till, the grasshoppers may occur early in the
season, but may be distributed across the field, especially if
the field was in pasture or fallow before planting.
Kentucky's three common grasshopper species
overwinter in the egg stage. Laid in masses of 20 to
130 eggs, they are placed in packets below the soil
surface. Generally, eggs are laid in uncultivated
ground in the fall and begin to hatch the following
spring. There is typically only one generation per
REDLEGGED GRASSHOPPERS Melanoplus
The redlegged grasshopper's upper surface is red-brown to brown in color, with a dull yellow-green
under surface. The wings are colorless, and the hind
legs are red with black stripes. They are
approximately 1 inch long when full grown.
The eggs begin hatching in early spring. Nymphs
molt five to six times (40-60 days). Although
solitary, it is generally the most prevalent of the
grasshoppers. When disturbed they either hop
vigorously to one side, or fly swiftly and noiselessly
straight ahead, suddenly dropping to the ground.
Distribution and abundance of this insect is impacted
greatly by climatic conditions, primarily humidity. It
occurs in pastures and meadow, along roadsides, and
borders of cultivated fields. Rarely it is found on dry
hillsides. Under climatic conditions where rainfall is
low (less than 30 inches/year), the redlegged grasshopper
can be a very destructive pest of clover, alfalfa, and
soybeans. Its feeding can completely defoliate
legumes, or expose seeds to pathogens. When
populations are high, it attacks almost any plant.
TWO-STRIPED GRASSHOPPER Melanoplus
The two-striped grasshopper's upper surface is dull
olive brown and a pale under surface that is pale
yellow to green. A narrow yellow stripe extends
from behind each eye to nearly the tip of the wing
covers. When full-grown this grasshopper is a
little more than 1 inch long. It is the most common
of the early summer grasshoppers. When disturbed,
it usually leaps vigorously and noiselessly for a short
The red locust mite, a natural enemy of
all life stages of grasshoppers, causes a great deal of
mortality in the two-striped grasshopper because it is one of the first species to to emerge in
the spring and it matures more quickly than other
grasshoppers (see Natural Controls).
Similar to the redlegged and differential grasshopper,
the two-striped grasshopper is found upon bottom lands, along the edges of
cultivated fields, at the margins of woodlands, and on
shaded mountain slopes. Unlike the redlegged
grasshopper, the two-striped can be found in both
moist and dry locations. The female seems to prefer
compacted soil, such as that found along roadsides,
as a site for egg laying.
DIFFERENTIAL GRASSHOPPER Melanoplus
The differential grasshopper's upper surface is dark
brown to olive green, the under surface is yellow. It
has clear, glossy hindwings. The chevron-like black
stripes on the large portion (femur) of the hind
legs are very distinct. This species is the largest of
the three; adults are 1-1/2 to 1-3/4 inches long.
The differential grasshopper avoids very dry habitats,
and shows a preference for cultivated lands. Alfalfa
and clover are particularly suitable for its
development; the eggs are often oviposited on field
margins. It has reported to injure grass, alfalfa,
indian corn, beets, orchard trees, mulberry, poplar,
and catalpa trees, and even grape vines. Preference
for cultivated lands make the differential grasshopper
of concern to farmers.
SCOUTING FOR GRASSHOPPERS
- CORN -- Grasshoppers are found in nearly all fields,
but are seldom a problem. They are more common
during the mid to late summer. To determine whether grasshoppers may become a problem, the question one needs to ask is: ARE THEY FEEDING ON THE
FOLIAGE OR ON THE EAR? Corn plants can
tolerate a considerable amount of leaf feeding
(>35%) before economic losses occur.
- TOBACCO -- Grasshoppers are found in many
fields, but are seldom a problem. IS THE FEEDING
THROUGHOUT THE FIELD, and ARE THE
GRASSHOPPERS STILL PRESENT?, are two
questions to ask before spraying the entire field.
- VEGETABLE CROPS -- While they are commonly
found in most crops, they are rarely a problem.
When scouting vegetables for grasshoppers, it is
important to determine if they are attacking the
marketable portion of the crop.
IN GENERAL, grasshoppers are a problem along
field margins, near areas of recent of mowing, etc.
The USDA-APHIS program in rangelands considers
at least 8 adult or an equivalent number of nymphs
per square yard as an economic infestation level that
Synthetic insecticides such as Asana, Sevin,
Malathion, and Diazinon are recommended for
control. Flaky wheat bran treated with Sevin, or
Nosema locustae is recommended when control is
needed near water or near threatened and/or
endangered wildlife. Nosema locustae (Noloc), is a
naturally occurring bioinsecticide which has been
developed for grasshopper control. It is a registered
protozoan microbial insecticide.
Natural enemies (living organisms which use
grasshoppers as a nutrient source) are the reason why we
generally see only localized outbreaks of grasshoppers.
Many natural enemies are specialists on orthopterans,
while others are generalists, using grasshoppers as
one of many hosts.
Fungi attack grasshoppers. A diseased grasshopper body
may be soft, with fungal bodies evident to the naked eye.
The red locust mite, Trombidium locustarumRiley is an important natural enemy. This mite feeds
on the egg stage, and will also attach itself on various
parts of nymphs and adults. The red locust mite
uses its mouthparts to suck up the fluid from its
host. A mite-infested grasshopper drags itself
around, eats little, and dies early.
worms, a type of nematode, are a notable natural
enemy also. Infested grasshoppers rarely produce
young (see ENTFACT 613, Horsehair Worms). Other types of
nematodes are natural enemies too. Nematode eggs
are laid on plants, and are eaten by grasshoppers. The
young nematodes burrow through the wall of the
stomach, and with high levels of infection/infestation
they can cause death, primarily due to dessication.
There are several dipterous parasites of grasshoppers,
including Tachinidae and Sarcophagidae fly species.
Tachinidae flies oviposit eggs on the nymph or adult,
and the emerging tachinid larvae eat their way into
the body of the grasshopper. Parasitized grasshoppers have soft, flabby bodies, and are slow
moving. Generally, parasitized grasshoppers die
earlier and do not reproduce. Sarcophaga sp., flesh
flies, attack in a manner similar to Tachinidae flies, although the
maggots do not kill the host.
Egg predators such as bee flies, blister beetles
(Epicauta pennsylvanica), and Scelionid wasps are
important natural enemies, too. Ground beetle adults
and larvae feed upon the eggs. Vertebrate predators
such as skunks, shrews, moles, salamanders, toads,
and snakes feed upon grasshopper eggs too.
Predation of nymphs and adults by toads, snakes, and
birds (hawks, blackbirds, crows, bluejays, prairie
chicken, mockingbirds, and bluebirds), have an
impact on the population too, although they feed
primarily during the summer season.
REDLEGGED ---- hind leg is red with black stripes --- prefers humid environments
TWO-STRIPED ---- narrow yellow stripe extends from behind each eye to nearly
the tip of the wing covers --- prefers humid environments
DIFFERENTIAL --- chevron-like black stripes on the large portion (femur) of the hind
legs ---- prefers humid environments and cultivated fields
CAUTION! Pesticide recommendations in this publication
are registered for use in Kentucky, USA ONLY! The use of some products
may not be legal in your state or country. Please check with your local county
regulatory official before using any pesticide mentioned in this publication.
ALWAYS READ AND FOLLOW LABEL DIRECTIONS FOR SAFE USE OF ANY
This page is maintained by Pat Dillon, Department of Entomology, University of Kentucky.
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