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Adult squash bugs are flattened in appearance and approximately
one-half to three-fourths inch long. Gray to black in color,
adults are winged, with orange and brown stripes visible on the
edges of the abdomen. Eggs are one-sixteenth inch long and
yellowish-brown to brick red in color. Upon hatching, nymphs are
wingless, pale green to white, with red legs, heads and
antennae. As nymphs mature, they become more gray in color with
black legs. Adults overwinter in plant debris around fields or
wooded areas. Young nymphs that are present in late fall when
temperatures begin to decrease will freeze and die off. In the
spring, adults emerge as temperatures warm. At this time they
fly in search of fields and begin mating. Females lay eggs
individually in clusters of seven to 20 on the undersides of
leaves; each cluster is laid in a "V"-shaped pattern formed by
two leaf veins. Egg laying usually begins in mid-June and
continues into summer. Eggs hatch in one to two weeks in late
June and early July. Young nymphs feed in groups on the
undersides of leaves. Squash bugs have five nymph stages in our
area and reach maturity in five to six weeks. Adults emerge in
late summer and continue feeding until the first frost.
Damage to host plants is caused by both adults and nymphs.
Young nymphs feed in groups near where they hatched, while older
nymphs feed on the entire plant. Squash bugs suck nutrients from
the leaves, disrupting the flow of water and nutrients. As they
feed, small yellow specks develop on the leaves and later turn
brown. Severe feeding may cause entire leaves to turn brown and
die. Feeding by the squash bug also causes plants to wilt. Vines
wilt from the point of feeding to the end of the vine. Leaves
turn brown, then black and eventually die. Wilt symptoms
resemble symptoms of bacterial wilt, a disease of cucurbits.
However, if squash bug populations are controlled soon enough,
wilted plants should recover. Plants infected with bacterial
wilt would continue to wilt and die. Both nymphs and adults also
feed on the fruit. Severe damage may cause the fruit to be
unmarketable.
Control of squash bugs is difficult. One way is to remove the
eggs from the leaves. Of course, some have hatched out already.
Sprays of pyrethroids, such as bifenthrin, are effective against
at least the younger nymph stages. The organic control has been
sabadilla dust, but beware: Sabadilla dust is one of the most
toxic things you can handle.
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 Ragweed time
If you're one who usually suffers from the fall allergy season,
you know the symptoms all too well. Many people blame goldenrod as
the culprit, when it is mostly ragweed problems. In our area, we
have two types of ragweed. The most noticeable is giant ragweed.
Giant ragweed, also called horseweed, can grow well over 10 feet
tall. It is very noticeable as one of the few weeds that grow taller
than our Illinois corn. The other type of ragweed is common ragweed.
It is generally less than 6 feet tall and not nearly as noticeable.
Ragweeds tend to bloom in late summer. The period can range from
mid-August to mid-September. They put out a lot of pollen when they
bloom. The amount of pollen is one problem, but the shape of the
pollen is the other. The shape of the pollen is more jagged and
sharp along the edges, making it more of an irritant than other
types of pollen.
Add in the usual ragweed problems, alternating wet and dry
conditions, and early leaf drop, and we have the recipe for an
allergy sufferer's nightmare. There are also several leaf molds that
are at work, and that compounds the allergy problem.
What can you do? One, try to eliminate ragweed in your particular
area. Two, avoid the mid- to late morning period in the great
outdoors. This is when more pollen is released. Three, you can stay
indoors (or in office or car) with air conditioning. And, if your
problems are particularly troublesome, talk to your doctor. There
are prescriptions and over-the-counter products to help alleviate at
least some of the symptoms.
This has probably been one of the worst years in history. This
year's season started almost a month earlier than normal and even
eclipses the past two years. So take some comfort in the fact that
next year will probably be better. I've said that the last two years
in a row, but there is always hope!
[Text from file received from
John
Fulton, University of Illinois Extension,
Logan County Unit]
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Low-life squash bugs and allergy-inducing pollen producers
