Transcript AG-FS-03.451-10.2 Forest Insects 6-9-04 PP2

Georgia FFA
Forestry CDE
Insects
By: Josh Fleming Jenkins Co.
FFA Advisor
May 2007
Insects List
•
•
•
•
•
•
•
•
•
•
Ambrosia Beetle
Aphids
Bagworm
Black Turpentine Beetle
Conifer Sawflies
Cicada
Eastern Tent Caterpillar
Fall Webworm
Gypsy Moth
Insect Gall
•
•
•
•
•
•
•
•
•
Ips Engraver Beetle
Locust Borer
Nantucket Pine Tip Moth
Orangestriped Oakworm
Pales Weevil
Pine Webworm
Scales
Southern Pine Beetle
Southern Pine Sawer
Ambrosia Beetle
D
A
M
TOP
VIEW
ID TIP: Note Points on Abdomen
A
G
E
FRASS
1/16” to 1/4” long, stout bodied; the mature color is dark reddish brown
Ambrosia Beetle
Damage from beetle
boring into tree trunk
Ambrosia Beetle Larva
Inside Tree Trunk
Aphids
• Description of Adult1/32 to 1/4 inch long
Soft-bodied, pearshaped.
Varying in color from:
red, yellow, green, blue
brown, gray, or black.
Nymphs resemble
adults but are smaller
and lack wings.
Aphids
Sooty Mold, a black, sooty growth on needles, leaves
and/or branches is sometimes found growing on the
honeydew that is excreted by Aphids. Some types of
ants can be seen collecting the secretions of the Aphid.
Bagworm
Adult females don’t fly and are
confined to the bag for life, males do
fly and will locate females in the fall
to mate. The bagworm can extend
out of the bag to feed, but will retract
The bag that encompasses the bagworm is back into the bag when threatened.
made of silk, portions of leaves, and
Often found in bald cypress, junipers,
twigs, the bag can be 2’’ long or more.
arborvitae, and other conifers
Black Turpentine
Beetle
Side View
Top View
Black Turpentine
Beetle
Pitch Tubes from this beetle are about the size of a quarter and are seldom found more
than 10’ off the ground. This beetle prefers to enter a tree through some type of
damaged area: Mechanical Damage, naval store operation, and lightning are common
points of entrance into a tree. Outbreaks are often preceded by drought.
Conifer Sawfly
Loblolly
Pine Sawfly
Larva
White Pine
Sawfly Larva
Red-headed Pine Sawfly Larva
Just a few
examples of
the different
types of
Conifer
Sawflies
which affect
Georgia
Trees.
Introduced Pine Sawfly Larva
Conifer Sawfly
Adult Red-headed Pine Sawfly
Sawfly adults are broad-waisted wasps, and the
female has a serrated ovipositor which allows
them to saw little slits in the needles where eggs
are laid. Once the eggs hatch, the larva begin to
feed on the foliage of the host plant. Some species
have one generation per year, while others may
have 3 or more generations per year. The larva
stage of each generation will severely defoliate
the host plant, especially with more than one
generation per year.
Cicada
Adult
Shell
• Cicada’s come in 2 major
varieties, Annual or periodical.
Annual cicada’s are present
each year, and their shells can
be seen on tree trunks
occasionally. Periodical
cicadas emerge once every 13
or 17 years. 17 year cicadas
usually occur in the northern
US, and the 13 year cicadas
usually occur in the southern
US. In Georgia, the last 13
year brood occurred in 1998,
and the last 17 year brood
occurred in 2004.
Cicada
Female cicadas damage trees by ovipositing on twigs and small branches. Eggs are
laid in the Y shaped pits of living twigs. Each pit may contain up to 20 eggs. A
female may lay up to 600 eggs. Once they hatch the nymphs drop to the ground,
burrow underground, locate a suitable rootlet for feeding and begin to suck juices
from the roots as they develop into an adult. This process may take up to 17 years
from start to finish. At the end of the cycle, the Adults will emerge between May
and June.
Eastern Tent Caterpillar
A Silk “Tent” will house the
larva as the feed on tree
foliage. These tents can be
found in the forks of limbs
and branches and are used as
a base for feeding larva,
which venture out to
different branches to feed.
Full grown caterpillars reach
about 1.6’’ in length. Color
varies, but generally have black
heads, mid-dorsal white stripe,
and lateral white stripes between
each pair of legs.
The adult moths are
light brown with 2
diagonal white stripes
across the back side
of the wings.
Eastern Tent Caterpillar
Total defoliation
of the tree foliage
can occur with
large broods of
the Eastern Tent
Caterpillar.
The egg mass of this caterpillar is Infestations of
this size warrant
laid on twigs of the tree species
drastic control
that is a suitable hosts for this
measures to
insect. Common host trees are
ensure that fruit
cherry, apple and plum trees.
Control of this insect ranges from crops are not lost
for the current
removing egg masses from the
year.
tree, hand picking caterpillars
from the tree after hatching, or
using chemical control.
Fall Webworm
The Fall Webworm is a very common pest to Pecan, Sourwood, and Persimmon
trees. This worm will construct large, unsightly webs made of silk around the
leaves that it is feeding on. Often these webs will cover entire branches and may
contain hundreds of worms. This insect can cause sever losses to commercial
growers, but for most individuals, the problem is ugly webs present in their trees.
Fall Webworm
The Fall Webworm adult varies in appearance, usually being an all white
moth, but it can have light brown coloring on its wings. The Pupa of the
moth is dark in color and is around 3/8” to 1/2” in length. The activities of
the Fall Webworm larva go mostly unnoticed until late summer or early fall
when the grey silk nests begin to appear in the host trees.
Gypsy Moth
The Gypsy Moth Caterpillar is a serious spring defoliator of forest and shade trees. The
Egg mass can be seen on tree trunks and branches. The caterpillar can be found in the
spring of the year feeding on tree foliage, usually Oak Trees, and is usually 1.5” to 2”
long. The caterpillar can be identified by a series of blue and red dots along its back.
The male Moth is brown in color, with large feathery antennae, the female is white in
color with some colored markings on the wings. This pest has been eradicated from
Georgia 3 times since 1991, but new infestations are easily sparked when people
unknowingly transport egg masses, caterpillars, or pupa from infested areas.
Insect Gall
Plant Galls can be caused by numerous different insects. The gall itself can be caused
by Chemical Secretions from adult insects while laying eggs, or an abnormal reaction
from the plant to the saliva of the feeding larva. Often times it is easier to identify the
insect by the gall, than actually seeing the insect. The location of the gall on the plant is
very useful in identifying the insect. The following link will connect you with a table,
which will aid in identifying insects from their galls.
Forest Health Guide for Georgia Foresters - Gall Insects
Ips Engraver Beetle
The Ips Engraver Beetle can easily be
identified by its scooped out rear end
when compared to the Southern Pine
Beetle. This beetle carves long tunnels
into the tree trunk, just beneath the bark.
This insect does not always produce
pitch tubes on the trees it feeds on, but
boring dust can often be seen on tree
bark. If a pitch tube can be seen, it
usually occurs on the bark and not in a
crevice. These beetles prefer to infest a
stressed tree, but will infest healthy trees
during an outbreak.
Locust Borer
The cause for concern from the Locust Borer
is the large grub like larva stage. These
insects feed on live wood, therefore will not
enter debarked trees. This is one reason why
when logs are decked after harvest for long
periods of time sever loses can occur.
Nantucket Pine
Tip Moth
Adult Moth on
pine needle,
adults are about
1/4” in length
with 1/2” wing
span, with
irregular brick red
and copper
patches on wings.
Larva
Feeding at
base of
needles.
This moth causes the most damage to recently planted
pines up to 15 ft in height. Loblolly and shortleaf
pine are the favored hosts, but the moth will infest
slash and longleaf if conditions are favorable. Sever
stunting and deformation of younger trees can result
from repeated attacks of this pine tip moth.
Orangestriped Oakworm
Orangestriped Oakworm
The orangestriped oakworm feeds on various oaks and
sometimes birch and hickory. Mature caterpillars are just
over 1 ½ inches long, black with eight longitudinal orangeyellow stripes. They also have two black spines on the
second thoracic segment and smaller spines on each
succeeding segment.
Pales Weevil
Weevils that debark pine seedlings are
the pales, and pitch-eating. These
weevils damage seedlings by chewing
bark from the stem above and below
the ground. Seedlings are often girdled.
Damage can be prevented or reduced
when conditions favoring their
development are avoided. Debarking
weevils are attracted to recently logged
areas with pine stumps.
Adult weevils deposit eggs in roots of
freshly cut pine stumps or buried
slash. The larvae hatch in a few days
and begin feeding beneath the bark.
Upon emergence the new adults will
seek out seedlings to feed on. The
newly emerging weevils and older
adults attack seedlings planted on or
adjacent to these cut over areas.
Pales Weevil
Guidelines to reduce weevil damage:
1. Delay planting one
year on cutover pine sites
if harvest cannot be
completed before July.
2. If planting cannot be
delayed the seedlings
should be dipped in an
approved insecticide or
top sprayed in the nursery
before lifting.
3. Delay cuttings/
thinnings that are
adjacent to recently
planted pines until the
seedlings are 3-4 years
old.
4. Planted seedlings can
be sprayed in the field
with an approved
insecticide if weevils
begin to appear.
Pine Webworm
Caterpillars are approximately 3/4 inch in length at maturity; tan to gray with two
darker longitudinal stripes along each side. The larvae feed on the needles
constructing masses of frass bound together with silk on the seedlings. These masses
of excrement are usually 3 to 5 inches long surrounding the twigs and enclosing the
basal portions of the needles. No control is necessary.
Scales
Scale insects can be injurious to pines in seed orchards and a nuisance in Christmas tree
plantations. This group of insects is very large; containing minute and highly
specialized individuals. Different species attack different parts of the host, branches and
twigs being frequently infested. After the first molt the females lose their legs and
antennae and become immobile and sessile. A waxy covering is then secreted over their
body. This covering may be in the form of powder, plates or drops of resin. The females
remain under the covering where they lay eggs and give birth to living young. The eggs
are never laid in the open. There may be one to six generations per year varying with
species and geographical location.
Southern Pine Beetle
Southern Pine Beetle
• The southern pine beetle is the
most destructive pine bark beetle
in the South. Randomly flying
females locate susceptible trees,
which are called focus trees.
• The SPB attacks all species of
southern yellow pines including
eastern white pine. It is
particularly destructive in over
mature and overcrowded stands.
Outbreaks are cyclic and are
usually preceded by drought or
flooding.
• Trees are killed when thousands
of adult beetles bore underneath
the bark to feed and lay eggs. The
female beetles construct winding
S-shaped galleries in the
cambium while feeding and
laying eggs. Adult beetles carry
blue stain fungi and these fungi
once introduced into trees will
proliferate into the sapwood
stopping water movement within
the tree.
• The usual signs of attack on the
outside of trees will be pitch tubes
in bark crevices when formed.
Southern Pine Sawyer
Insects that attack and bore into living trees or freshly cut logs are generally referred
to as wood borers. Softwood species are most often used for log homes, and include
pine, spruce, fir, hemlock, northern white cedar, western red cedar, and cypress. In
warm weather, freshly cut logs of all softwoods are frequently attacked within a few
days after tree felling. These beetles do not infest logs that have been debarked;
therefore, rapid utilization of felled logs is essential to prevent attacks. Logs that are
decked for several weeks often sustain heavy attacks from these beetles.
THE END!!!
Created: May 2007