Integrated Pest Management for Christmas Tree Production: A ...

CLIPBOARD/FLAT SURFACE
Hold a clipboard or another fl at surface
under a branch to collect mites, aphids,
or other insects dislodged by tapping the
branch (Fig. 15). The back of a clipboard
that has been painted to have one half
black and one half white is very useful when
beating trees to detect pests. The inside
back cover of this manual is a good fl at
surface to use.
PRUNERS/POCKET KNIFE
Growers may need to clip symptomatic
twigs or branches to observe them more
closely for signs of insects, mites, or disease
spores. Collecting samples for identifi cation
by a diagnostic expert (Fig. 16) may also be
necessary.
BOTTLES/PLASTIC BAGS
Occasionally, growers need to collect samples
to examine at a later date or send to a
diagnostic laboratory. In addition to bottles
and plastic bags for collecting samples,
having a method of labeling the specimens
(permanent marker, adhesive labels, etc.) is
also helpful. Any sample collected in alcohol
should be labeled with a pencil-written
tag inserted into the vial.
Monitoring Tips
1. During the growing season, a scout
should be monitoring fi elds weekly to
look for evidence of pests, diseases, and
other problems.
2. If possible, scout on cloudy days. The
muted sunlight makes it easier to observe
chlorotic, or yellowed, symptoms
in the fi eld. Some pests are also more
visible in subdued light.
3. When monitoring blocks for problems,
scouts should walk through the fi eld
while keeping an eye out for obvious
problems. They should also select nonsymptomatic
trees in a random pattern
to inspect more closely. For these trees,
be sure to look at the inside for discoloration.
4. Prune a few twigs from the interior
and lower portion of the tree for closer
inspection.
5. Tapping branches over a fl at surface
will dislodge insects and mites, making
them easier to see (use the tapping
sheet at the back of this manual).
Trapping
Several types of insects can be monitored
using traps. The traps are usually baited with
pheromones (insect-produced attractants)
or other chemicals (Fig. 17) and placed in
the fi eld. They are designed to hold the
insect until the trap can be checked by
a scout. When monitored regularly, the
collection data can help with the timing
of control applications. Traps are used for
monitoring purposes, not control. For more
information on trapping, see Appendix E.
Sticky cards are another type of monitoring
tool used to trap insects. These
adhesive-coated index cards, which come
in various sizes and colors, may be used
to monitor the emergence of small pests
(Fig. 18). For example, in the case of some
scale insect pests, 3-by-5-inch sticky cards
are used to attract the adult male life stage.
The cards are attached with clothespins
to scale-infected tree limbs before the
expected time of emergence. Cards can
then be monitored regularly.
Figure 18. Yellow sticky cards used to trap
fl ying adult male scales. Courtesy of Cathy
Thomas, PDA
Diagnosis
Proper identifi cation of the pests that
have been found through the monitoring
process is an important next step in the
pest management process. With training,
experience, and the use of printed and Web
resources and guides, growers or scouts can
usually make an accurate diagnosis. For
diffi cult samples, consult an expert or a
diagnostic lab. Regional inspectors for the
state department of agriculture and county
extension educators can be very helpful in
obtaining necessary expert assistance. For
contact information for select agencies, see
Appendix K.
Figure 15. Tapping branches
over a white notebook or fl at
surface to dislodge and observe
pests. Courtesy of Brian Schildt,
PDA
Figure 16. A good set of pruners.
Courtesy of Joseph O’Brien,
USDA Forest Service, Bugwood
.org (#5044044)
Figure 17. White pine weevil
trap. Courtesy of Cathy Thomas,
PDA
IPM BASICS ............................................................................................................................................................................................................................................................................................ 11