Q. I have a pomegranate tree planted by birds about 20 years
ago. I never had bug problems on this tree before 2011. In 2012 it produced about
150 pounds of pomegranates. In 2013 the tree did not produce any fruit at all.
This year the tree is loaded again but it is infested with those little red
bugs that I think will turn into those ugly creatures you have been talking
about. We don’t want to use poisons. Have there been any new developments for
control?
A. This particular bug, the leaf footed plant bug, is a
growing problem for Las Vegas gardeners. The only way you will have a good crop
of pomegranates, and most likely pistachios, is to spray.
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| Leaffooted plant bug on pomegranate |
The two choices
you have are to spray with a conventional insecticide, which you call a poison,
or spray with some sort of “organic” spray which I guess you might call
non-poisonous.
you have are to spray with a conventional insecticide, which you call a poison,
or spray with some sort of “organic” spray which I guess you might call
non-poisonous.
Conventional
insecticides leave a longer residual on the plant so you do not have to spray
as often. Most organic sprays must be repeated more often because they don’t
have much of a residual or none at all.
insecticides leave a longer residual on the plant so you do not have to spray
as often. Most organic sprays must be repeated more often because they don’t
have much of a residual or none at all.
One of the
most effective “organic” sprays is soap. You can make your own soap sprays but
for most people I would highly recommend buying insecticidal soap already made.
The soap used to make insecticidal soaps is less damaging to plants than
grabbing scented Ivory liquid and using that.
most effective “organic” sprays is soap. You can make your own soap sprays but
for most people I would highly recommend buying insecticidal soap already made.
The soap used to make insecticidal soaps is less damaging to plants than
grabbing scented Ivory liquid and using that.
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| Safers insecticidal soap |
Insecticidal
soaps, to be effective, must be sprayed directly on the insect. They have no
residual. When these bugs die from the soap, new ones will come in and invade
their territory so you have to re-spray frequently.
soaps, to be effective, must be sprayed directly on the insect. They have no
residual. When these bugs die from the soap, new ones will come in and invade
their territory so you have to re-spray frequently.
The most
effective time to spray soaps is toward dusk when bugs have settled in for the
night. Soap sprays are not selective. They will kill any insect that comes in
direct contact with your spray, good or bad.
effective time to spray soaps is toward dusk when bugs have settled in for the
night. Soap sprays are not selective. They will kill any insect that comes in
direct contact with your spray, good or bad.
Organic
sprays containing pyrethrum, an insecticide derived from either Dalmatian or
Persian chrysanthemums, will probably work well. However, pyrethrum is a
poison. Use it carefully and wear protective clothing.
sprays containing pyrethrum, an insecticide derived from either Dalmatian or
Persian chrysanthemums, will probably work well. However, pyrethrum is a
poison. Use it carefully and wear protective clothing.
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| Pyrethrum farmer in Kenya |
Synthetic
or manufactured sprays that chemically resemble pyrethrum, which you would categorize
as a poison, are probably going to be effective as well. Scientists “tweaked” the
chemistry of pyrethrum to give it more “knockdown power” and last a little
longer. These are called synthetic pyrethroids.
or manufactured sprays that chemically resemble pyrethrum, which you would categorize
as a poison, are probably going to be effective as well. Scientists “tweaked” the
chemistry of pyrethrum to give it more “knockdown power” and last a little
longer. These are called synthetic pyrethroids.
Chemical
names in the ingredients will say things like “Permethrin” or “pyrethroid”. These
chemicals emulate natural pyrethrins but are manufactured and as such are not “organic”.
If you decide to go conventional, then look for these names in the ingredients.
Make sure the label permits you to apply it to fruit trees.
names in the ingredients will say things like “Permethrin” or “pyrethroid”. These
chemicals emulate natural pyrethrins but are manufactured and as such are not “organic”.
If you decide to go conventional, then look for these names in the ingredients.
Make sure the label permits you to apply it to fruit trees.
What actual harm do these insects do? I have a pomegranate tree that is over thirty years old and is prolific in its fruit production. These insects have appeared on the tree in almost all of the 20 years I have lived here and I have yet to see any damage directly attributable to them. I will be very interested in your response.
In small numbers, they don't cause a lot of problems. In large numbers their feeding can cause fruit and nut drop on pistachios or cause them to form "blanks", no nut inside the kernel. In extreme cases a total loss of fruit and nuts for that year.
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I have the same problem with these bugs on my three pomagranite trees. It is said they could affect some nut trees also, does that include Walnut trees?