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| Grasshoppers have
been a crop pest since the beginning of time and are
mentioned in the Bible (The Biblical locusts were a
species of Grasshopper) And the LORD said to Moses,
"Stretch out your hand over Egypt so that locusts
will swarm over the land and devour everything
growing in the fields, everything left by the hail."
So Moses stretched out his staff over Egypt, and the
LORD made an east wind blow across the land all that
day and all that night. By morning the wind had
brought the locusts; ... (Exodus 10;12 - 13)
Grasshoppers can be a serious pest in
the garden depending primarily on environmental and
seasonal factors. Exceptional populations of grasshoppers occur when weather, predators,
parasites and pathogens combine in a way that allows more-than-usual
numbers of eggs and nymphs to survive. A wet / cool spring, with
temperatures below 65 degrees, results in less eggs hatching. A warm,
dry spring will result in more grasshoppers in the fall and makes
grasshopper control a necessity for gardeners.
Grasshoppers, being extremely
mobile are difficult to control. Grasshopper eggs
begin hatching in late Spring and early summer. The
immature grasshoppers ( nymphs) feed on tender grass
and succulent plants in the area where they hatched.
As Grasshoppers develop they spread to adjacent
areas such as your Garden and feed on an
increasingly-diverse variety of plants. Grasshoppers
chew almost any type of leaves, but generally prefer
softer vegetation. They'll favor lettuce, for
example, rather than tougher material, such as tree
leaves. As far as vegetables go, they prefer
lettuce, carrots, and onions. If given a choice,
grasshoppers usually avoid squash, peas and tomatoes
leaves. (They do, however, like tomato .)
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If grasshopper control is a major problem
, besides planting the softer vegetables that grasshoppers
prefer, a good strategy is to plant early-maturing varieties
of other crops that you can harvest before mid -to -late
August.
Grasshopper nymphs live for up to 2 months, after
which the adults appear and continue feeding until they are killed by
cold weather. While adults are busy reproducing and laying eggs, nymphs have only one
focus... To Chow down on your Lawn and Garden. Damage caused by grasshoppers appears as irregular
holes at the edges of leaves.
Natural Controls
Some insects commonly feed on
grasshoppers. Blister beetles feed on grasshopper eggs - but
you really wouldn't want them around just for the sake of
grasshopper control as they also bite animals and humans
leaving nasty little blisters.
Many birds feed on grasshoppers. - But
birds will also feed on many of your ripe garden crops . You
will have to judge whether using birds in a grasshopper
control scheme is actually advantageous. If you believe it
would be then consider that many birds hunt by watching for
movement from a comfortable perch, if your not concerned
with birds also eating your crops you could put multiple
perches such as trellises, posts and other upright
structures to attract birds who will assist in grasshopper
control as well as controlling other garden pests.
Adult robber flies are common predators of
grasshoppers during summer . Composite flowers such as
dandelion, chrysanthemum, yarrow, sunflower, dahlia and
zinnia attract robber flies as well as predatory wasps and
other beneficial insects including pollinators. I
generally have sunflowers scattered randomly in advantageous
spots, not just for grasshopper control but they have other
benefits as well.
Praying Mantids
are an adored beneficial insect and a general predator of
most pest insects including grasshoppers.
Young grasshoppers prefer sheltered spots
of dense vegetation, it is here that they fall prey to
spiders, toads, ground beetles, and other predators.
Patches of dense mixed grasses and flowers can serve as
early-season traps for young grasshoppers.
Horehound ,
cilantro ,
and calendula
are herbs that repel grasshoppers. Planting a border of
these plants , or having them scattered around the garden
area will help keep grasshoppers at bay. Garlic not
only repels vampires and the opposite sex but it also repels
grasshoppers - Garlic oil
also serves as a deterrent of grasshoppers as well as other
Garden pests - it must continuously be reapplied.
Managing Grasshoppers with Baits and
Sprays
Sprays and or baits are a successful
grasshopper control only if properly used, they must be
applied to developing stages of grasshoppers and
concentrated at egg laying sites . Ability to control
grasshoppers declines as the grasshoppers mature and
scatter.
The most effective grasshopper controls are baits that contain
Nosema locustae
a single-celled protozoan that infects and kills most species of grasshoppers,
locusts, and some crickets. It is non-toxic to humans, and animals. Nosema
locustae Should be applied early in the season.
Nosema locustae
is sold under the trade names of NOLO Bait or Semaspore. Only young grasshoppers
are susceptible, and it is ineffective as a grasshopper control after adult
migrations have occurred. It is also fairly slow acting and does not equally
infect all grasshopper species. It may effect some varieties of Praying
Mantis.
Baits containing
Sevin
are also somewhat effective. Bait formulations are made by
mixing the insecticide with a grain favored by the
grasshopper and it kills off any that feed it.
Sevin
baits become ineffective after a rainfall and must be
reapplied.
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