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How to control a thrips infestation

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AndrewAZ:
I think I brought them onto my property after buying some rose bushes at the big box stores.   I've tried a whole bunch othigs, trimming off infected branches,  need oil.  Been trying for over a year and no luck.

pagnr:
I had thrips on Persimmon trees in containers. It is important to spray the undersides of the leaves, where the larvae are clustered.
See if you can see larvae on the leaf undersides. These can be easier targets than the adults.
You need to rig the sprayer nozzle to point upwards, possibly a long wand will help ( more so if you are also fighting Gnomes and Trolls ).
Also they have a life cycle where they moult in the soil, then reemerge as adults, so you need to repeat the spray process to interrupt the lifecycle.
You can knock a lot of larvae off with a water spray.
I used Pyrethrum and Neem sprays. Possibly Hort soap sprays would work.
It useful to have a spray nozzle set up like spray painting every leaf, low volume, mist, wide fan.
As the larvae were moulting in the pot soil, a fertiliser application with wetting agent, a surfactant ( basically a safe detergent ) seemed to interrupt them too.

Millet:
Pagnr, gave you good information.  I use a horticulture oil spray for both thrips, scale, mealy bugs, and aphids,  Works well.

jbclem:
I have what I think are thrip nymphs/larvae, visible with a handheld 10-15x LED microscope.  They are torpedo shaped, translucent enough so that you can watch their excrement go from inside to outside, dropping as lines of small dark green blobs.  They are on my seedling vegetable plants in an indoor growing area and are hard to find because there aren't that many of them compared to the number of lesions (and blobs) they create.  I'll occasionally  spot one or two in an area where there are lots of the dark green excrement blobs.  They are in the same size range as spider mites, but move around a lot more than the spider mites and are no where near as numerous.  I've never seen their eggs or an adult thrip.  Does it sound like these are thrip larvae?  I've looked them up and some photos seem to confirm this.

I've been spraying them with Safer's Soap and that seems to work...but they keep coming back. Would Safer's Soap act as a safe surfactant if I mixed it with fertilizer to use in the soil as mentioned? 

Pagnr, could you tell me which spray nozzle you've found most useful for reaching the underside of leaves?

pagnr:
Pagnr, could you tell me which spray nozzle you've found most useful for reaching the underside of leaves?

Using a small 10 litre sprayer with a pumped handle to pressurise, pretty common type.
I found it most useful to have an extension to double the wand length and/ or also a longer hose from the tank to the wand.
It makes it easier to wave around, and also not move the spray tank so much, or have to lift it.
Also an elbow bend on the nozzle end, easier to point upwards.
If you can adjust the spray pattern of the fitted nozzle to a wide fan, that can make coverage easier without having to look too hard.

Irrigation mister nozzles can give a wide fan, with less spray volume used. Might need an inline filter fitted to stop clogging the finer nozzle hole.
Or be careful when mixing to strain out lumps, and shake tank to prevent slugs forming.
Brass nozzles on screw threads can be fitted to the plastic nozzle on the sprayer.

Not sure I have seen Thrip larvae moving much, seem to cluster under the leaves on the main vein. Infested plants are often silvery looking from the feeding activity. Adults and larvae were present at the same time. However there are a lot of species, so couldn't be sure they all behave like that.

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