Q. I was advised to spray
my nectarines and peaches with a garden pesticide containing pyrethrum to kill thrips.
Would you still eat the fruit once this chemical has been applied? And if I
spray it, will the fruit not be deformed?
my nectarines and peaches with a garden pesticide containing pyrethrum to kill thrips.
Would you still eat the fruit once this chemical has been applied? And if I
spray it, will the fruit not be deformed?
 |
| Thrip damage to netarine. |
A. If the label for this
pesticide does not have fruit trees or gardens on the label, then it should not
be used for that purpose. This is a legal response, not a technical response to
your question.
pesticide does not have fruit trees or gardens on the label, then it should not
be used for that purpose. This is a legal response, not a technical response to
your question.
Nectarines, not peaches, are deformed and scarred mostly
because of the feeding damage on the skin of the fruit by Western flower
thrips. These insects are tiny but when there are hundreds of them all feeding
on the skin of one nectarine, they rip and tear at this so badly that the fruit
becomes deformed and scarred horribly. Killing off the thrips prevents fruit
deformity and scarring.
because of the feeding damage on the skin of the fruit by Western flower
thrips. These insects are tiny but when there are hundreds of them all feeding
on the skin of one nectarine, they rip and tear at this so badly that the fruit
becomes deformed and scarred horribly. Killing off the thrips prevents fruit
deformity and scarring.
Strangely enough, thrips damage does not occur on peaches
so they will not have to be sprayed. Evidently the hair on the peach skin is
enough to interfere with the feeding damage by these extremely small, flying
insects.
so they will not have to be sprayed. Evidently the hair on the peach skin is
enough to interfere with the feeding damage by these extremely small, flying
insects.
By the way, thrips are so primitive they don’t have wings
like most insects. They have “sticks” that come out of their body with hairs on
them. They are very poor flyers and can’t travel very far.
like most insects. They have “sticks” that come out of their body with hairs on
them. They are very poor flyers and can’t travel very far.
 |
| /Thrip. Not my picture but don’t remember where I got it. |
On the label of the pesticide it tells you how many days
you must wait before picking fruit. This is called the “Re-Entry Period” or
“Days before Harvest”.
you must wait before picking fruit. This is called the “Re-Entry Period” or
“Days before Harvest”.
 |
| Years ago I had to find out if the damage was because of thrips so I put this fine mesh insect netting around an apricot tree. The fruit was not damaged. It was due to thrips. |
There is a lot of science that goes into that label. It’s
not guesswork. It does not mean that the pesticide is totally gone. It means
that a reasonable amount of the pesticide has been degraded by our weather and
the EPA has deemed it “safe to eat” if the fruit is washed before eating.
not guesswork. It does not mean that the pesticide is totally gone. It means
that a reasonable amount of the pesticide has been degraded by our weather and
the EPA has deemed it “safe to eat” if the fruit is washed before eating.
As far as the insecticide goes, it is called a synthetic
pyrethroid and does a good job killing most insects including those in the
home. However, on thrips it does not do a great job. Spinosad is much better to
use and organic to boot.
pyrethroid and does a good job killing most insects including those in the
home. However, on thrips it does not do a great job. Spinosad is much better to
use and organic to boot.
 |
| Doesn’t say it in the common name but this contains spinosad. |
But Spinosad is lethal
to bees so spray only when there are no flowers present in the tree or beneath
it and bees have gone home for the day. This will be at dusk. Rotate this spray
with Neem oil and soap sprays.
thank you for sharing such a nice content thrips damage your plant slowly and they die ultimately and your yield is gone now I came to know why it is very important to save your plants from thripsthrips here you can find some additional information which you may seem useful too. thanks
The NIH, with billions in funding, disagree with what you say.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3324680/
The University of California IPM mentions that pyrethrins work but I have had no success spraying pyrethrins on grapes and controlling leaf hoppers. The reason I like Spinosad is because it will also control the grape leaf skeletonizer which coincides very nicely with the first application needed for grape leaf skeletonizer. You can get early control of leafhoppers using Spinosad knocking the population back but not control the adult leafhoppers at all. I have noticed this with my own applications on grapes. Spinosad is permitted on grapes but it has no effect on whiteflies. So the three big problems on grapes in southern Nevada are grape leaf skeletonizer starting in about April, followed by whiteflies starting about June and thirdly leafhoppers with young ones beginning about April and continuing through the whole summer. If you don't get leafhoppers under control they will be back the following years. There are so many different pyrethrins out there (resmethrin, permethrin, cypermethrin, etc. which do you use? Try the original pyrethrin and let me know if it works on leafhoppers.