Nurseries should be scouting poly-houses for pest problems
Recent heat waves have given insects a jump-start this spring, so pest problems we usually don’t see until early May could happen in the next two weeks. Nurseries will find insects in the poly-houses and container holding areas much earlier than usual.
In poly-houses, watch for outbreaks of aphids by looking for the cast skins (like dandruff), check for spider mites by looking for stippling and yellowing of infested foliage, and look for broad mites by being alert for new shoots that turn black. Check suspect infestations of spider mites by placing a white piece of paper under branches and rapping the branch sharply over it, dislodging mites onto the paper. Broad mites are too small to see without a microscope, so send samples to MSU Diagnostic Services to confirm infestations. The following insecticide products can be used when damaging infestations are found.
Marathon, Tristar, Flagship, Safari, or Aria can be used as a soil drench to prevent problems with whiteflies, aphids, mealybugs or soft scales.
Aphids: Aria, Azatin, Benefit, BotaniGard, Decathlon, Discus, Distance,
Endeavor, Enstar II, Flagship, Kontos, Marathon, Ornazin, Orthene 97,
Precision, Safari, Tame, Talstar, Tristar.
Spider mites: Akari,Avid, Floramite, Hexygon, Judo, Kontos, Ovation, ProMite, Pylon, Sanmite, Shuttle-O, Tetrasan.
Broad mites: Avid, Akari, Judo, Pylon, SanMite.
Broad mites are less than 0.3 mm (smaller than a period in font size 12 print).
New Guinea impatiens Photo Credit:Leanne Pundt
Saliva Photo Credit: Leanne Pundt
Broad mite symptoms
Swedish Ivy distortion of leaf edges
Downward curling of leaves
Green peach aphids.
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