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The past couple of weeks, when the magnolia blooms were in the
pink-bud stage, spruce spider mites became active. These mites
are one of the major downfalls of spruce in our area. Spruce
spider mites, along with other spider mites that attack
evergreens, are active in the spring and fall. This is opposite
of the two-spotted spider mite that is active during the heat of
the summer. Heavily attacked trees often lose branches and can
even be killed. Even the loss of branches can render an
evergreen worthless in the landscape. To determine if you have
spruce spider mites, hold a piece of white paper under a branch
and shake it. The mites will look like moving dust specks on the
paper. They will also leave a green streak if rubbed on the
paper, and that's a good way to distinguish them from dust or
plant material. If mites leave a red streak, they are predatory
mites. These predatory mites eat the bad mites, so high numbers
will control your problem. Many times, there will be some fine
webbing, like spider web, visible on the needles as well.
Spruce spider mites can be controlled with sprays of
acequinocyl, bifenthrin, cyfluthrin, insecticidal soap or summer
oil spray. The soap or oil sprays will require a second
application about a week later to give good control. These mites
normally remain active until mid-May, but the cool conditions
thus far may extend their life cycle this year.
Other spring pests are also indicated by the saucer magnolia.
During the bloom stage, going on now, the ash plant bug, fall
cankerworm, spring cankerworm, Fletcher scale, leaf crumpler,
eastern tent caterpillar, juniper webworm and Zimmerman pine
moth are susceptible to control. As we get to the petal-fall
stage, European pine sawfly, gypsy moth, hawthorn mealybug,
honeylocust pod gall and willow aphid become susceptible to
control.
Some plants are great indicators of insects. The plants and
insects develop at the same temperatures. It just took somebody
like Mr. Orton to put it all in print.
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Master Gardener plant sale
This Saturday the Master Gardener plant sale will make its annual
appearance. The sale will be from 9 to noon in the Exhibition Building
at the fairgrounds. Enter the fairgrounds through the south gate by
the caretaker's trailer. I know they have been busy this year with
several varieties of day lilies, rhubarb, hostas, geraniums and many
more. The group does the annual sale as a fundraiser for their many
activities and to help beautify the community.
Reminders
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Mow the grass as
it is needed. Try to remove no more than one-third of the leaf
blade to do away with catching or raking grass.
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Broadleaf control
is just around the corner for many weeds. Look at early May for
control.
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Grub control is
largely unsuccessful in the spring because of large grub size
and a short life cycle. Look to August and September for grub
control.
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Moles are active,
but controlling the grubs won't help much now. For control, look
to a noose or scissor trap or one of the soft baits with poison.
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The average last killing frost date is
about May 5 for our area, and many gardening charts use May 10
for planting tender crops in our area.
[By
JOHN FULTON,
University of Illinois Extension, Logan County] |
