Extension Fact Sheet

email: uge1067@arches.uga.edu

BAGWORMS, MITES, SCALES

During November and December the homeowner should inspect and treat shrubs for the following insects:

ARMORED SCALES

(see picture below)

Host Plants:                  Boxwood, Gardenia, Holly, Juniper

Identification:                Scales secrete a protective hard waxy covering over their bodies. Female scales are small (1.3 to 1.5 mm), flattened and disklike.  They lack legs, antennae and eyes and can vary in shape and color.  The winter is spent as eggs, which the female deposits under her shell before she dies.  The eggs hatch in the spring and the crawlers anchor themselves to new plant growth, remaining in one place until they move to mate.

Damage:                      Scales weaken plants by sucking its fluids causing the leaves to turn yellow or  grow weakly.  A high population of scales gives the plant area a crusty appearance and may kill the plant.

Control:                       Spray Boxwood with Dormant Oil one or two times.  SprayGardenia with Dormant Oil one or two times.  Spray Holly with Dormant Oil two times. Prune out heavily infested parts.  Chemical control is effective in spring and   and  summer. 

BAGWORMS

(see picture below)

Host Plants:                  Arborvitae, Juniper, Maple, Various Conifers

Identification:                The female is wingless and grub like with tiny, useless legs. The male is a small, brown, hairy moth with clear wings.  The winter is spent as eggs in the mother’s bag.  They hatch in May & June, mature during August and September and mate.  The young worm secretes silk and forms a bag which  enlarges as the worm grows.

Damage:                       Defoliates plants.  Severe infestation can kill conifers in one or two seasons.

Control:                        Prune out infested twigs and branches at this time.

Chemical control is effective in June and July.

SOUTHERN RED MITE

(see picture below)

Host Plants:                   Azalea, Camellia, Holly, Juniper, and Rhodedendron

Identification:                Female is 0.38 mm long and resembles a small spider.  The abdomen is dark  reddish or brown, with a pale midstripe.  It is a “cool weather mite” and     reproduces rapidly in the spring and fall.  It is almost inactive in summer and winter.

Damage:                      The mite feeds on the lower leaf surface and infested leaves turn gray or brown and may fall from shrub prematurely.

Control:                       Spray with Orthene TTO, Horticultural Oil, or Insecticidal Soap one or two times at a two-week interval.

SPRUCE SPIDER MITE

(see picture below)

Host Plants:                   Juniper, Spruce, Hemlock, Arborvitae

Identification:                The mite resembles a small spider.  It is 0.38 to 0.42 mm long, almost black with a pale midstripe.  Two red eyespots are conspicuous.  Mites overwinter as eggs laid at the base of the needles.  They hatch in April and May, have several  nymphal stages, and do maximum feed and reproduction in fall.  Inactive in hot weather.

Damage:                       Considered the most destructive spider mite in the United States.  Feeding  causes needles to turn yellow or brown and drop off.  If a serious infestation, the plant may be webbed.

Control:                        Spray with Orthene, Diazinon, Malathion, or Insecticidal     Soap.

Spruce spidermites life stages

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The University of Georgia and Ft. Valley State University, the U.S. Department of Agriculture and counties of the state cooperating. The Cooperative Extension Service offers educational programs, assistance and materials to all people without regard to race, color, national origin, age, sex or disability.

Leah Wilson 11/02/02