BEES IN TURF
Prepared by: S. Bambara, R. Brandenburg & J. Baker, Extension Entomologists
CAUTION: This information was developed for North Carolina
and may not apply to other areas.
BEES IN TURF
There
are many common species of solitary bees that nest in individual
holes in the ground. They are all good pollinators. These bees range in size form 1/2 to 3/4 inches
and may be a variety of colors such as blue, green, copper or metallic
reddish-brown. They may belong to one of several groups of bees such as
the membrane bees, digger bees, sweat bees, mason bees and leafcutter bees
(Colletidae,
Halictidae, Andrenidae, Anthophoridae,
Megachilidae) and occur across the state. During the evening hours, females excavate
nesting burrows that reach six or more inches in depth. Some of these bees line
the burrow with a water-proofing secretion for protection from moisture. Small mounds of
excavated soil may appear around each nest opening. When bees are numerous, many
holes may be in closed proximity, creating a "citylike" aggregation. Each hole
belongs to an individual female. During the day, the active females collect
pollen and nectar to carry back to the nest to form a "ball" 1/8 to 14
inch in diameter that is placed within a "cell" excavated in the side of
the burrow. A single egg is laid upon the pollen ball in March, April or
early May. After hatching, the larva feeds on pollen and develops within
the cell into a new generation of bees. The new generation emerges the
following year in March or April. At this time, mating takes place and
bee activity begins to pick up as the nesting cycle resumes. Though adult
bees feed on nectar, none store honey as such. Solitary, ground nesting
bees play a vital role in ecological systems, especially in pollination
of crops and wild plants. Solitary bees are valuable pollinators and should
not be destroyed unless there is some compelling reason.
Ground-nesting bees generally prefer nesting in areas with morning sun
exposure and well-drained soils containing little organic matter. Burrows
are excavated in areas of bare ground or sparse vegetation. These bees
usually avoid damp soils. Damage to lawns and turf is usually minimal and
control is often sought because the bees are perceived as a danger or annoyance.
Solitary bees are not programmed to sting people and there is no mass attack as might be found
with honey bees or yellowjackets. A person might be stung if handling one roughly or if one was caught in clothing. Mowing and other outdoor activities can
be continued with little problem. However, with very large aggregations,
the faint of heart may prefer to avoid the area for 4 to 6 weeks while nesting is taking
place.
PEST MANAGEMENT
Cultural control methods include heavy watering or irrigation with a lawn
sprinkler during the nest- building period to discourage nesting. Tilling
of soil to destroy tunnels may help a little, but establishment of dense
turf is probably the best discouragement to further nesting. Applications
of heavy organic matter could be included as a soil amendment, if practical,
when tilling the soil. If the soil or location is not conducive to a healthy
lawn, using ground covers or heavy mulches may be an alternative solution.
Mulches may be used on bare patches caused by heavy traffic where grass
will not grow.
CHEMICAL TREATMENT
If chemical treatment is desired, recommendations for insecticides approved
for control of these insects in home lawns can be found under Bees and Wasps
in INSECT CONTROL IN HOME LAWNS in the NC Agricultural Chemicals
Manual. Recommendations
for insecticides approved for use on sod farms, golf
courses or other commercial sites can be found in COMMERCIAL
TURF INSECT CONTROL in the NC
Agricultural Chemicals Manual.
For additional information on insect control and pesticide use, contact your
county Cooperative Extension Center
.
Recommendations for the use of chemicals are included in this publication
as a convenience to the reader. The use of brand names and any mention
or listing of commercial products or services in this publication does
not imply endorsement by the North Carolina Cooperative Extension Service
nor discrimination against similar products or services not mentioned.
Individuals who use chemicals are responsible for ensuring that the intended
use complies with current regulations and conforms to the product label.
Be sure to obtain current information about usage and examine a current
product label before applying any chemical. For assistance, contact an
agent of the North Carolina Cooperative Extension Service in your county.
Other Resources
© 2001 NC Cooperative Extension Service
Prepared by: S. Bambara, R. Brandenburg & J. Baker, Extension Entomologists
ENT/ort-100, March 2002 (Revised)
Last reviewed by the webperson January, 2008.