spider mites

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TreeChopper1

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Have been seeing alot of blue spruces in my area dying because of spider mites. Do you guys have any suggestions? I appreciate the help.
 
If you catch them fairly early then there are much less expensive alternatives to avid.

You might try Suspend SC insecticide mixed with Hexagon df. Does a really good job this time of year. Later in the summer you may need to go to avid when you're dealing with heavy infestations of mature mites.
 
ID your mite, both 2 spotted and (obviously) spruce mite attack spruces. One is warm weather one is cool weather, treatment timing varies. If your treating for spruce mite in July, "your closing the barn door after the horse got out".
 
They are 2 spotted . I had the University of Iowa do tests at their lab and the told me early July is the optimum time to treat for them.
 
Tastar is OK very high rate=cost, as compared to a product that is formulated to eliminate the pest only in a desired stage of life. Avid very expensive but highly effective, hexagon lower cost and sterilizes only the female harmful mite but should be applied before damage is noticed.Now if your called in and mite damage is obvious ya talstar or avid, next year early application of hexagon and better-cheaper results. personally i never use talstar in any rate if mites might be an issue, just not worth the risk cause a lower rate of talstar will cause a might outbreak.
 
Avid would cost app $45. per 20 gal.
Talstar 1 would cost app $9. per 20 gal.
Hexagon I don' t know, but I will call my supplier tomm.

Woodville are you saying it will cause an outbreak due to ... ? You will be doing re-treats.
 
google cut and paste results

Physical and Chemical Controls. Spraying plants for spider mite control may provide some temporary relief, but is not recommended as spider mites can reproduce quickly. Insecticidal soaps and/or horticultural oils can be helpful when not phytotoxic. Pesticides can provide short-term control, but spider mites can develop resistance so they are not recommended as a long-term solution. When possible, keep temperatures below 75 degrees Fahrenheit. If pesticides are used, waiting at least two weeks before releasing biological control agents is advised.

Biological Control. Ongoing releases of biological control agents can help prevent spider mite outbreaks and reduce use of and resistance to pesticides. As a general rule, making several small releases over time rather than one single release is recommended for best results.

Predators. There are several species of predator mites and insects available for spider mite control. Some species are better adapted for warmer, drier environments; other species survive best in cooler temperatures with higher humidity. Contact a supplier of biological control organisms for more information about how to choose the right biological control agents for your needs.

Phytoseiulus persimilis. Known for quick control of spider mites, P. persimilis reproduces faster than spider mites and actively seeks out spider mite nymphs and adults. Prefers 60-85 degrees F 55-65% RH.

Neoseiulus californicus. Although not as quick-acting as P. persimilis, N. californicus can survive longer without prey. Recommended for all kinds of indoor and greenhouse situations. Prefers various temperature and humidity levels.

Stethorus punctillum. These tiny beetles are gaining popularity as reliable spider mite predators. They thrive in a broad range of temperature and humidity levels.

Orius insidiosus. Also known as minute pirate bugs, O. insidiosus is a tenacious general predator well adapted for dry and warm weather, the kind of weather spider mites thrive in. Prefers 60-80 degrees F/40-70% RH.

N. fallacis - Prevent and Maintain
Mixed Mites - Prevent, Control, and Maintain
F. acarisuga - Control and Maintain
P. persimilis - Control and Maintain
S. punctillum - Control and Maintain
N. cucumeris - Prevent and Maintain
I. degenerans - Prevent and Maintain

Chemical controls can also be effective, but great care must be taken as spider mites can easily develop resistance to many pesticides.
 
Great post Elmore!!

I was thinking specifically about a situation I saw yesterday here in Austin, where the temps are running 98-99 rh 65% and the mites are doing damage in island trees. These spruce are in poorly draining soils, in heat islands with little root zone, the year after a severe drought. Biological controls can be successful if the clients are willing to pursue a program, however in this particular case it is a strip mall that called pretty late into an infestation.

Will look into Stethorus punctillum as they may be able to tolerate the heat.

:bowdown:
 

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