farmergiles

Thrips (aka thunderbugs, greek- thysanoptera) are a common pest found in mj grows, both indoors and out.
Both the plural and singular is thrips. If there is just one it is still called a thrips.



These insects can cause harmful unsightly damage to plants. They can also act as a vector (carrier) for plant viruses.
Some species of thrips feed on insects or animals but we are concerned with the varieties that eat plants.

The first indication of thrips is often leaf damage.



It can be difficult to distinguish between thrips damage and spider mite damage. Thrips damage tends to have more of a shiny silver appearance.

They cause damage by rasping holes in the plant and sucking the sap.

Both larvae and adults feed on leaves and buds.
Just to add insult to injury they leave faeces everywhere too.

The length of the thrips life cycle varies with temperature- if temperature is lower the life cycle slows down.
However in the right conditions the life cycle could be 10 days or less enabling them to reproduce and develop resistance to insecticides quickly.
A female adult thrips can lay up to 300 eggs.

Mostly they lay eggs by making a hole in the plant and laying the egg there. The egg hatches then goes through larva, prepupa and pupa stages (the number of stages depends on the species) before becoming adults.





Thrips are mostly found on the leaves and flowers but they can also be found in soil around the base of plants.

Most adult thrips have wings, with distinctive fringes. Their greek name thysanoptera means fringe wing.
Not all thrips can fly. The ones that can fly are not good flyers but they can easily drift around on air currents.

Thrips are small, usually the adults are less than 2mm. The adults and larvae can just about be seen with the naked eye. They can move quite quickly.

Random facts about thrips
-They only have one mandible, on the left hand side.
-Fidel Castro has alleged that the US had dropped thrips onto Cuban crops as a form of biological warefare.
-The word thrips is also greek and means wood louse.

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farmergiles

The best way of avoiding thrips is to avoid them in the first place.

Some thrips can fly. Some of the non- flying varieties can drift on air currents. Some kind of filter on air intakes will prevent them being sucked into a growspace.

If any new plants are introduced to a grow from elsewhere, they should be carefully quarantined and scrutinised for pests. That way any pests can be dealt with before they infest the whole grow.

Thrips (and many other pests) are difficult to control on flowering plants, particularly in late flowering when many insecticides cannot be safely used so close to harvest.
So they should be kept out of any flowering space/garden at all costs.

Thrips are present in many places in the wild. If a grower goes out tramping the wilds and woods, they should shower and change clothes before going anywhere near a grow.

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farmergiles

First it is necessary to identify them. They can be a bit difficult to identify initially as they are quite small.
A 30x magnifier will show them- they can move quite fast though.
The damage looks as though the chlorophyll has been stripped from the plant. It cannot be repaired.
Unlike mites, thrips leave small specs of fecal matter on the pants.

Most thrips live in the soil at some stage in their life cycle so they are vulnerable to eradication within the soil.

Keep in mind that they tend to acquire resistance to many insecticides and go through a variety of different stages. So using different methods in combination or sequence may well be a good plan.

-Plant Sprays
Any insecticide which works on flying insects will kill the adults. However this may well not kill the eggs, larvae and pupae so treatment will need to be repeated as the subsequent generations emerge.
Because they become resistant to many insecticides quickly, eradication in this way can be tricky.

Soap spray works pretty well for the adults. Safers soap or other brands can be purchased from garden stores. A dilute solution of non-anibacterial dishsoap can be used just the same.
Plants should be watered 20 minutes or so before application to avoid the stomata on the leaves clogging with soap.
Spray the plants thoroughly. Wash off after 20 or 30 mins.

When using any sprays, always turn the lights off. Water + HID bulb = bang!

-Diatomaceous earth (DE) can be used to cover the top of the soil (or other medium), this dries out the exterior of thrips or any other insects in the soil, killing them.
The DE will probably have to be removed to water the plant, otherwise it may smother it.
So DE may need reapplying.
I'm not sure all thrips spend time in the soil.

-Commercial insecticides
There are many preparations available.

Those Containing spinosad are probably the most effective for thrips.
Spinosad is a nerve agent effective on certain insects only, thrips, fleas and lice are vulnerable, ladybugs and mites are not.

Also azadirachtin products like Azatrol work well.

Pyrethrium or neem products can be effective but the thrips tend to become resistant quickly.

Beware of using insecticides on plants late in flower. Especially insecticide which is not labelled food safe.

Always follow the safety instructions, wear protective clothing if necessary. Beware of inhalation in enclosed spaces. Follow the manufacturer's guidelines for application.

-Predators
Predators are great as they avoid the risk of contaminating the crop, unlike some insecticides.

Ladybugs and lacewings eat thrips. But because of the thrips' small size and the way the like to hide in out of the way crevices, these predators may not eliminate thrips entirely. They will help keep the numbers down.

There are species of mites (amblyseius cucumeris),


predator wasps


and predatory thrips that feed upon and kill thrips. These can be purchased and released onto a grow.
Care should be taken that the predators can survive in the temperature and humidity conditions in the grow. For example, some predator mites cannot survive if humidity is too low. Consult the vendor before purchase.

Whatever method you use, use it thoroughly. Don't give them a chance to adapt.

Garlic repels them, garlic can be planted around a grow.
The colour yellow attracts them. Avoid having any yellow plants or objects around an outdoor grow.

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Cultivate a stoic calmness

Jester4yall

So with your vast bugology you know you can never leave right.


But for real good info

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In matters of style, swim with the current; In matters of principle, stand like a rock. -Thomas Jefferson

You will encounter many distractions and many temptations to put your goal aside: The security of a job, a wife who wants kids, whatever. But if you hang in there, always following your vision, I have no doubt you will succeed. - Larry Flynt

farmergiles

It's like Royston Vasey!

__________________
Cultivate a stoic calmness

Jester4yall

I'm not gonna lie I gotta google it

__________________

In matters of style, swim with the current; In matters of principle, stand like a rock. -Thomas Jefferson

You will encounter many distractions and many temptations to put your goal aside: The security of a job, a wife who wants kids, whatever. But if you hang in there, always following your vision, I have no doubt you will succeed. - Larry Flynt