Mole crickets are insects that live underground and damage plants by chewing on stems and roots. They have enlarged digging legs that allow them to burrow. Males build underground tunnels to amplify their mating calls. Most mole crickets have wings but remain underground. They overwinter as adults and lay eggs in spring that hatch into nymphs that resemble adults but lack full wings. Nymphs mature through summer and become adults in fall. Mole crickets attack many seedling crops and can kill plants by cutting stems at the soil surface. Cultural, chemical, and biological controls can help manage mole cricket populations.

1. Mole Crickets
Family : GRYLLOTALPIDAE

3. Common Mole Crickets
Gryllotalpa sp.
– Mole Crickets have characteristic digging forelegs.
Males produce songs and build burrows to amplify
their love song.
– Their antennae are shorter than body. When dug up,
they do not leap away like other burrow-inhabiting
insects but dig their way back underground with
powerful strokes of the forelegs.
– Most of mole crickets have developed wings and are
capable fliers.

4. Mole Crickets
Biology & Lifecycle:
– Adults and larger nymphs chew on stems of seedlings
and smaller plants at the soil surface.
– The mole cricket has one generation each year and
overwinters as adults. which lay eggs in April through
early June.
– Nymphs grow slowly through the summer months and
start becoming adults in September. Most eggs are laid
in late spring through early summer.
– Females of both species lay clutches of eggs in
underground egg chambers.

5. MaleFemale

6. Environmental Factors:
mole crickets are present year-around,
with adults and large nymphs
overwintering. but inactivated by cold
temperatures and drought (they burrow
deeper underground).
Irrigation during drought allows them to be
active
Flooding forces them to migrate to higher
ground.

7. Adult:
– Adults are large, about 3 – 4 cm, with wings longer
than body
– Both adults and nymphs have enlarged and toothed
forelegs for digging.
– Expanded femurs (base of the hind legs) for jumping,
although only nymphs jump.
– All species have soft bodies, with the middle body
section protected by a hardened cover (pronotum).
Immature:
– Nymphs range from less than 3mm at hatching to
about 2.5 – 3cm several months later, resembling the
adults but without trace of wings in the first 4 instars
and with small wing buds in later instars.
– The number of molts varies from 6 to 9 .

8. Mole cricket life cycle

10. Host range & damage:
– Mole crickets attacks seedlings of eggplant, sweet
pepper, tobacco, tomato, potato, and cabbage.
– Mole crickets kill plants by girdling and severing small
plants at the soil surface. Severed plants may be
pulled below ground to be consumed.
– Mole crickets cause more damage to turf and pasture
grasses than tomato and pepper in greenhouses
because of the use of soil fumigants , and soil
solarization.
– Mole crickets disturb roots and desiccate plants by
tunneling .

11. Seedling severed at soil surface by mole cricket feeding

12. Monitoring
Scouting:
– Galleries (tunnels just under the soil surface,
like miniature mole galleries) are evidence of
presence.
– Dead plants are evidence of activity.
– Mole crickets may be flushed from the soil by
flooding a small area with a 0.5% soap
solution.
– No thresholds have been developed.

14. Cultural Control
Transplants:
– Use larger transplants with larger stems.
– Use un-perforated plastic films for 2 weeks before
transplanting aids in killing mole crickets in planting
beds.
Field Manipulations:
– Mole crickets can quickly invade fields cleared of
crickets with fumigation or other methods. Therefore,
locate fields away from sources of mole crickets (such
as Johnson grass or Bermuda grass pastures) and
plant in large blocks with proportionally little edge.

15. Chemical Control
– The use of broad spectrum soil fumigants or
soil solarization under plastic film kills mole
crickets in the planting bed; however, crickets
survive in the untreated area between rows
and can re-invade the treated planting beds.
– Commercial insecticides baits can be applied
between beds to control residual crickets.

16. Natural Enemies
– Application of Entomopathognic Nematodes
(Steinernema sp. & Heterorahbditis sp. ). -
Populations of this nematode is harmless to non-
target organisms •
– Beneficial wasp Larra bicolor is recorded attacking
mole crickets. The wasp lays eggs on pest mole
crickets, and the wasp grubs that hatch from the eggs
kill the mole
– The parasitoid Ormia depleta was recorded in It is
attracted to the calls of male mole crickets and has
resulted in reduced mole cricket injury.

17. EPN attacking Mole cricket

18. Larra grub on mole cricketLarra wasp stinging and ovipositing
on mole cricket