These Mites Rain Down To Save Your Strawberries | Deep Look

Two tiny mites duke it out on strawberry plants throughout California. One is a spider mite that sucks the juices out of the delicious crop and destroys it. The other, persimilis, is a crafty predator that growers drop by the thousands from high-tech drones to protect their fields.

DEEP LOOK is an ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Explore big scientific mysteries by going incredibly small.

Individual spider mites are barely visible, about the size of a grain of salt, but together they cause huge damage to crops around the world. They suck sap from the leaves and stems of crops and houseplants, leaving yellow or dry rusty leaves and tangles of fine silk.

Farmers can use pesticides to knock them back, but spider mites quickly develop resistance, making them particularly stubborn pests.

So many farmers turn to biological control agents. One of the most popular is another type of mite commonly called persimilis. This predatory mite hunts down spider mites and their eggs.

But spreading the tiny hunters over vast agricultural fields is a challenge, so some growers are turning to companies like Parabug to disperse the predators by air using drones.

Now, entomologist Christian Nansen and engineer Zhaodan Kong at UC Davis are looking at ways to automate this entire process of crop protection. They’re developing a strategy using drones armed with special cameras to detect changes in the way sunlight bounces off plants' leaves.

Software using machine learning algorithms would then read the subtle changes in the leaves' reflectance and come up with a diagnosis about what was causing the stress. If the system suspects a spider mite infestation it could then summon a second drone, packed with predatory mites. The team is working on developing software to accurately drop the predators right on the trouble areas.

“The idea is that these natural predators are like tiny paratroopers coming in on the drones,” said Nansen, “with a special eye in the sky that sees exactly where they need to go.”

--- What are spider mites?
Spider mites are not insects. They're arachnids, more closely related to spiders and ticks.

--- How do I get rid of spider mites?
One of the best ways to get rid of spider mites on houseplants and garden crops is to spray the plant with water to knock the mites off. There are pesticides that will kill them, but spider mites have a knack for becoming resistant. Oils are also used to smother the mites. Biological control agents like predatory mites can be particularly effective.

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Samurai Wasps Say 'Smell Ya Later, Stink Bugs' | Deep Look

How Ticks Dig In With a Mouth Full of Hooks | Deep Look

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🏆Congratulations🏆 to these 5 fans on our Deep Look Community Tab for identifying the sharp mouthparts of the Persimilis mite - chelicerae!

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Yann Cohen
RandomAlex
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ZeGamingCuber

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[DIOsNotDead]

persimilis look like tiny little strawberry clones with legs, as if the strawberry was the mother ship and they get deployed to destroy invaders

[definingcomedy]

I am here eating my strawberries knowing that sacrifices were made for them to reach my house safely. RESPECT to the mites. 💗

[terramater]

So tiny, yet so important! Just like we repeatedly preach: every single species plays its role in this world.

[pendadenda]

Props to the mites and the camera man who shrunk himself intensely and filmed this for us.

[justarandompenguin]

I love the fact that, as times go by, farmers find ecological, more natural ways to deal with pests and such problems. Like those guys in Thailand that use ducks to clear pests from rice paddies.

[marlin]

"Eat the vegetarians" said Persimilis

[izzy]

That's way better than developing stronger pesticides.

[bazookallamaproductions]

this is like some sort of action movie plot.

this is EXACTLY the weirdass content i subscribed for.

[noaht]

“Looks like meat’s back on the menu, boys!”

[dmitrimikrioukov]

Lady bugs also eat spider mites. And the red mites that you find under rocks in spring and autumn are also predators, they do the same thing.

[CJCroen]

As someone who enjoys strawberries, I salute the Persimilis and their sacrifice.

[koko_law]

Persimilis mites: "JUSTICE RAINS FROM ABOVE!"

[RexRagerunner]

Persimilis: *deployed*
Pesticide: We weren't expecting special forces.

[jekblom]

"hunting down the unwanted vegetarians."

I know that feel.

[Yassir.A.P.]

"Need backup. Calling in air support at strawberry field!"
"Roger that."

[frostbitetheannunakiiceind]

Farmer: *"I use the mites to destroy the mites"*

[simonbelmont]

drones done wrong: military or spies
drones done right: protecting crops using ecofriendly alternatives

[StrangerApex]

I really love Laura's sweet voice explaining us calmly

[joemontemayor]

Entomologist here! I actually work with twospotted spider mites and persimilis on my research project! Persimilis are widely used in strawberries here in Florida as well and Parabug operates down here too. Great footage, love seeing mites get some recognition!

[cromcorgetti]

"You know who else has mites? You!"
Aight, gonna sprinkle me some predator mites on my face