Virginia Entomologist 6:1998



A couple of things to be on the lookout for:

Spruce Mite

Spruce mites are active already in Lynchburg based on a sample from last week, so the rest of the state is probably also seeing some activity. It would be a good idea to start scouting non-pine conifers for the presence of these mites. See the scouting guide in Pest Management Guide 456-017, pages 196-199 and page 207.

Tropical Soda Apple

This noxious weed has not been found in Virginia but the USDA has records for North Carolina and Tennessee. Mr. Ray Ebbett who is working the ID Lab this summer has prepared a fact sheet and collected some web links on this new pest. Take a look at:

http://www.ento.vt.edu/Facilities/OnCampus/IDLab/NewPests/TSA/TSA_Main.html

(Tropical Soda Apple is part of the Federal Survey Program that I help coordinate so I get to deal with weeds from time to time)

Sweet Potato Weevil

This is another pest we are looking for this summer. Like TSA it has not been found in Virginia but has the potential. We have records from North Carolina but as far as we know it has not been found in the Commonwealth. I am looking for cooperators to hang traps in each of the following counties/cities: Virginia Beach, Suffolk, Isle of Wight, Brunswick, Southampton, Greensville, Sussex, Accomack, Northampton and the Experiment Station in Painter. I am hoping maybe a Master Gardener in each of the counties has sweet potatoes planted in their garden and is willing to hang a couple of traps in mid-July and send the traps back in late September (this would be a nice return for all the MG talks I have given over the years). Please contact me if you are interested in helping out on this survey either at 540/231-4899 or idlab@vt.edu

Regardless see the link for SPW:

http://www.ento.vt.edu/Facilities/OnCampus/IDLab/NewPests/SPW/SweetPotatoWeevil.html


Insects to be on the Lookout for in May
(resent completed update)

Eric Day
Manager, Insect Identification Laboratory

Insect:Host(s)      Description                   Treatment timing*
FIELD AND VEGETABLE CROPS
 
Aphids:             Look for small soft-          Cut out and destroy small
Any crop but in     bodied insects causing        localized areas on plants or
particular cru-     the leaves to be stunted,     treat with an insecticide
cifer crops         yellowed, and/or curled.      labeled for aphids and that
                                                  particular crop.
 
Black Cutworm       Medium to large cater-        If more than 5% of the plants
and other           pillars cut off plants        are cut, control with an
Cutworms:           at the base. Inspect          insecticide or bait is
Many crops but      newly planted seed beds       warranted.
in particular       and newly set plants.
corn
 
Flea beetle:        Small black beetles jump-     Spray with Sevin when damage
Corn, eggplant,     ing like fleas when dis-      becomes severe.
and many other      turbed form the leaves of
crops               a plant. They scrape the
                    upper epidermis layer off
                    the leaf and sometimes the
                    fruit, leaving a brown scar.
 
Imported            Velvet green caterpillars     Treat when caterpillar
Cabbageworm:        with a faint yellow stripe    populations reach a threshold
Cabbage, broc-      down the back and a row of    of one worm per plant, repeat
coli, cauli-        yellow spots on each side.    every 5 to 7 days as needed.
flower, and         Full grown larvae are about
other crucifers     32 mm (1-1/4 inches) long.
 
Root Maggots:       White legless maggots         Usually a planting time soil
Many vegetable      feed on small roots and       insecticide is needed but a
and field crops,    tunnel into large roots.      soil drench after plants have
particularly        Plants with damage fail       been set may be effective.
crucifer crops      to develop properly.          Replanting is effective
                                                  because there is usually only
                                                  one generation of maggots and
                                                  the second planting is not
                                                  attacked.
 
 
FRUIT INSECTS
 
Codling Moth:       Pinkish-white caterpillars    If using pheromone traps,
Apple and pear      enter fruit at calyx end      treat if you exceed 5/trap/
primarily, but      and tunnel all the way        week.
cherry, peach,      to the core. Adult moths
plums, apricots,    are grayish-brown with
and similar fruits  irregular golden brown lines
are attacked        on the forewings. 1/2-3/4"
                    wingspan.
 
European Red        Mites are very small and      This mite is resistant to
Mite: Apple         range from red to green.      many miticides, so make sure
pear, plum,         Foliage turns a sickly        that the chemical you will
prune, and          bronze color as if covered    use is effective. A dormant
many other          dust.                         oil applied at the 1/2" green
trees and                                         leaf stage or earlier in the
shrubs.                                           spring is important also.
 
Green Apple         Pale green nymphs on the      Treat when 50% or more of the
Aphid:              underside of leaves and       shoots are infested.
Apple, pear         new shoots, often a pro-
                    blem on trees with exces
                    sive shoot growth due to
                    overfertilization.
 
Spotted Tenti-      Young mines are serpentine    Treat young mines with Vydate
form Leafminer:     changing to oval. As the      or Lannate if more than 3
Apple               larvae get older they form    mines per leaf on average.
                    the leaf into a tentlike
                    structure.
 
 
ORNAMENTAL INSECTS
 
Azalea Stem         Look for tips dying back      Treat mid-May and mid-June
Borer: Azalea,      and yellow legless grubs      with an insecticide or cut
rhododendron,       up to 1/2" long boring in     out and destroy dead and
mountain-laurel,    twigs and trunk.              dying tips as noticed. Use of
blueberry                                         a borer paste in the holes
                                                  will give some control also.
 
Boxwood             Adults are out April to       Apply insecticides for
leafminer:          early May. Infested leaves    adults; apply systemic
Boxwood             often appear blistered and    insecticides in early to
                    discolored. See the March     late June to control larvae.
                    1990 issue of the Plant
                    Protection Newsletter for
                    more information.
 
Bronze Birch        Look for the top of the       Treat mid-May, and early-,
Borer: Birch,       tree dying back and up        mid-, and late-June; spray
cottonwood,         to 1" long flat-headed        trunk and branches heavily
poplar, aspen       borers under the bark.        and leaves lightly.
 
Camellia Scale:     Scale is light to dark        Treat May 10 and 20 and/or
Camellia            brown, 1/10" long and         Sept. 10 and 20.
                    oyster-shaped. Crawler
                    dates are May 1-June 5;
                    and Sept 15-30.
 
Dogwood Borer:      As many as 50 white cat-      Treat mid-May, repeat at
Dogwood, some       erpillars with brown          6 week intervals 2-3 times.
times pecan         heads living under rough-
                    ened areas of the bark.
 
Dogwood Twig        A slender lemon-yellow        In early to mid-May, apply
Borer: Dogwood      beetle grub feeding in        an insecticide spray to
elm, viburnum,      the center of twigs. As       control the adults. Prune out
and many fruit      it feeds it makes small       and destroy infested twigs.
trees               holes to the outside for
                    the protrusion of frass.
 
Eastern Tent        Look for conspicuous egg      Pick off egg masses before
Caterpillar:        masses circling twigs.        they hatch. Treat with an
Many fruit trees    These egg masses will be      insecticide as soon as the
but in particular   black in color and quite      leaves have emerged enough
cherry              shiney as if varnished.       to retain the insecticide.
                    The small black hairy
                    caterpillars will hatch
                    out in April and feed on
                    the newly emerging leaves.
 
Elm Leaf            Newly hatched larvae are       Control newly hatched larvae
Beetles: Elm        yellowish with black mark-     in late-May and early-June.
                    ings, adults are olive
                    green with two black lines.
 
Euomymus Scale:     Females are dark brown,       Treat May 20-25 and
Euonymus,           oyster-shaped, males are      and Aug 5-15.
bittersweet, and    elongate and white.
some ivy ground     Crawler dates are May 5-
covers.             June 10 and Aug 1-25.
 
Florina Hemlock     Cast skins give trees a       Treat May 20-25 and
Scale: Hemlock      white-washed appearance       June 5-10.
fir, spruce, yew.   with many scales on the
                    undersides of needles.
                    Scales under close examination
                    are yellow in color.
                    Crawler stage peaks
                    May 15-June 20.
 
Hickory Leaf        Galls shaped like             No control is needed on established
Stem Gall:          bullets develop on the        trees as these galls do not harm
Hickory.            petioles and shoots.          large trees seriously.
                    Leaves with galls fall        Young nursery stock can in
                    off the tree prematurely,     some cases be killed and an
                    causing concern by the        insecticide applied just as the
                    tree's owner. Galls are       leaves open may be warrented.
                    formed by aphids.
 
Lace Bugs:          New damage will not be        Lace bugs overwinter as
Andromeda, oak,     apparent yet this year,       adults on deciduous plants.
azalea, walnut,     but last season's damage      Treat in late May and repeat
rhododendron,       appears as stippling          in June and July. On evergreens
sycamore.           and brown droppings on        lace bugs overwinter in
                    the leaves.                   the egg stage.
 
Lilac Borer:        Look for the white borer      Control adults with an
Lilac, Ash,         3/4-1" long just beneath      insecticide in early
privet.             the bark.                     May and repeat six weeks
                                                  later. Borers can be killed in
                                                  their burrows with borer paste
                                                  or a long flexible wire.
 
Oystershell         Scales are dark brown         Treat May 5-10 and/or
scale: Most         and oyster shaped. They       July 15-20.
fruit trees and     can build up to extreme
ornamentals.        numbers at times and almost
                    cover twigs and small
                    branches. Crawler dates:
                    May 1-20 and July 15-25.
 
 
Pine Needle         The female scale is white     Treat May 5-20 and/or July 15-20.
Scale: Nearly       and about 1/10" long. Its     Single infested branches can be
all species of      shape varies but is usually   pruned out.
pine as well as     wider at one end. The male
many other ever-    is smaller and has 4 parallel
greens.             ridges down the center.
 
 
 
Southern red mite:  Damage is seen as finely      Treat in late April to early May
Holly, pyracantha,  stippled leaves with a        and late September to mid-October.
azalea, camellia,   yellowed, chlorotic, or
rhododendron, and   russetted appearance.
other broad-leafed
evergreens.
 
Spruce mite:        Small mites, 1/50" long,      Spray with a miticide in mid
Arborvitae, spruce, cause a yellow stoppling      May and early fall.
juniper, hemlock.   on the leaves and die-
                    back of the lower branches.
                    in severe cases older branches
                    may turn brown and die.
 
 
White Peach Scale:  The Female scale is white     Treat May 1 and 10, Jul
Most fruit trees    with a yellow mark on the     5-15, September 1-10.
and many            center and has a rounded
ornamentals         shape. The male is solid
                    white and elongated in shape
                    Crawler dates are April 25-
                    May 15, July 1-15, and
                    August 20-September 15.
 
 
White Pine Weevil:  The larva is a yellow,        Prune and destroy infested
Pines and spruces.  legless grub that feeds       shoots in May and June.
                    under the bark on the
                    terminal leader. The leader
                    wilts and droops in the
                    spring indicating the
                    presence of the grub.


* See Virginia Pest Management Guides for recommendations on insecticides and rates. Use insecticides only when high population levels demand control action. Most plants can support small populations of pest insects.
Eric Day
Insect Identification Laboratory
Department of Entomology
215 Price Hall
Virginia Polytechnic Institute and State University
Blacksburg, VA 24061-0319
(W) 540-231-4899
Fax 540-231-9131

See my lab homepage:

http://www.ento.vt.edu/Facilities/OnCampus/IDInfo.html