in other words
august28
2012
Diggin in the Dirt: Fall Pests Arrive
By Chip Bubl
Oregon State University Extension
Service
Columbia County
The OSU Food Preservation
Hotline will be available Monday,
Tuesday, Thursday, and Friday from
9am until 4pm at 1-800- 354-7319 until
October 12, 2012. In addition, you can
call our local OSU Extension office at
503 397-3462 with food preservation
questions and to get your pressure canner
tested.
Vegetable topics
This has been great corn
weather. Many gardens have corn in full
tassel. All you need to do now is keep
the water going, fertilize with something
like urea or blood meal along the corn
row if the leaf color is too yellow-green
and wait for harvest. That waiting isn’t
easy.
I have had several calls about
blossom end rot on tomatoes. This isn’t
surprising given the heat recently. There
is a rumor going around that tomatoes
need to be under-watered to produce the
best (or earliest) crops. This isn’t true!!
All you will do is increase the blossom
end rot. If the soil is short of moisture,
especially in a high temperature stress
situation, the plant can’t move enough
calcium to support both the leaves and
developing fruit. The lack of adequate
calcium causes the end rot. The biggest
fruits are often the most affected. Liming
isn’t enough. The plant roots need
enough water to move it around.
It is easy to have too many
zucchinis, cucumbers or green beans.
However, it is important to continue
to remove the fruit from the plants.
Otherwise, new flower and thus fruit
production is slowed. Keep the plant
picked and your plants will produce
longer.
The fall webworm arrives, as does the
alder flea beetle
I’m sure you have noticed the
brown webbing in many trees recently.
This is the work of the fall webworm.
The adult is a moth that is active from
late June through July laying
eggs in
all manner of trees. The eggs are laid on
the underside of leaves. Alders, apples,
cherries and willows are commonly
affected but the potential host range is
very large.
Alder leaf beetle larva and damage.
The eggs hatch about ten days
after being laid and the larvae spin webs
around the foliage. These webs protect
the caterpillars from predators. As the
caterpillars grow, they can consume a lot
of leaves. But does this hurt the trees? I
have seen severe infestation of a cousin
to the fall webworm (the western tent
caterpillar) totally defoliate alder trees in
the Alston/Delena area only to have the
trees recover completely a month later
after the caterpillars stopped munching
and pupated. The same thing is true of
the fall webworm. The pupae stop eating
in mid September and stay of sight until
the adult moths emerge next June. The
tree damage is cosmetic and short-lived.
No spraying is required.
As many natural populations
go, there is an ebb and flow to the fall
webworm. Diseases, birds and insect
parasites take their toll on the webworm
populations. As the webworm outbreaks
get bigger over a few years, the parasite
populations follow slightly behind. Then
the webworm cycle crashes and so does
the predator base, starting the boom and
bust cycle all over again.
The alder flea beetle was
widespread in a lot of Columbia
County this year. Alders had a lot of
leaves skeletonized by both the larva
and adult of this insect. The small,
black, worm-like larva rained down on
homes, gardens, and landscapes. The hot
weather of several weeks ago seemed
to knock a lot of the larva off the tree.
Since they don’t eat much but alders,
they seemed a bit disorientated to be
on the ground. But perhaps they were
just getting ready to pupate in the soil
beneath the leaf litter. There they stay
until they emerge as small, metallic black
with blue tinges adult beetles about 10
days later. The adults then fly back up
into the alders and eat some more. Then
they over winter and next spring emerge
to eat, mate, and lay eggs on the leaf
undersides to restart the cycle. As
with the tent caterpillar, no control is
needed. Alders will recover. Numbers
of alder flea beetles are higher this year
than they have been for many years.
That won’t last, either. Flea beetle
larva photo courtesy of Robin Rosetta,
OSU Extension entomologist.
9
offer is really important.
The Extension Service offers its
programs and materials equally to all
people.
Free newsletter
The Oregon State University
Extension office in Columbia County
publishes a monthly newsletter on
gardening and farming topics (called
County Living) written/edited by yours
truly. All you need to do is ask for it and
it will be mailed to you. Call 503 397-
3462 to be put on the list. Alternatively,
you can find it on the web at
http://extension.oregonstate.edu/
columbia/ and click on newsletters.
Contact information for the Extension
office
Oregon State University Extension
Service – Columbia County
505 N. Columbia River Highway (across
from the Legacy clinic)
St. Helens, OR 97051
503 397-3462
Email: chip.bubl@oregonstate.edu
Share your extra fruit and vegetables
with the Food Bank. What you can
COME ONE, COME ALL
Help support Logger Athletics
Greenman Field
August 30th from 6-8 pm
VHS Cheerleaders will be hosting a cleanup
day to get ready for the 2012 Football
Season. A grant from True Value Hardware
has enabled us to get paint and supplies.
The cheerleaders have already cleaned up and prepped
the field and stadium. VHS is looking for community help
in finishing up the project.
Please gather in the stands at 6pm if you are able to help.
For more info: Cheer Coach Denise Way cheercoachdee@gmail.com
or Betsy Miller bmiller@vsd.k12.or.us
Offers Good Through August 31, 2012