Anyone know what these ganja loving grubs are in the earth?  i am in hua hin and they seem to be eating my roots, plus the roots of my friend's plants who lives nearby.

 

what are they, and any good ways to make them go away?

 

 

Hard to identify the exact species of grub (beetle) but can say, with surety, that it’s not an Eurasian Hemp Borer, thankfully. It could be: Japanese Beetle, European Chafer or June beetle.

 

The “go to” solution is Not recommended. Neonicotinoids is a systemic insecticide that will stay in the plant. Cannabis, a hyperaccumulator plant that will uptake the insecticide where it will remain in the dried flower and leaves. Do NOT use this in any form with cannabis.

 

Look for Milky Spore powder as an organic alternative. It’s is the bacterium of Bacillus Popilliae or Paenibacillus Popilliae. It is highly effective. Water it into the soil and the bacterium will kill the grubs, leaving no residue or unnecessary uptake by the plant. You can find a form of Milky Spore Powder in a good agricultural or garden supply store. It might be available on Lazada. Here are a couple of pics of like products…
 

 

Two other biological control agents for beetle grubs that are definitely available in Thailand;  

(the pics attached are from products on the shelf at an ag shop in MaeJo, Chiang Mai.) 

 

https://biocontrol.entomology.cornell.edu/pathogens/Metarhizium.php

 

https://en.wikipedia.org/wiki/Beauveria_bassiana

 

IPM preventive management methods can include sanitation, cleaning up piles of wood and green waste, netting compost piles and the soil surface around your plants where adult beetles emerge from pupa stage and fly to new sites to breed and lay eggs that become the larvae that feed on the plant material. 

if beetles, bacillus thuringiensis kurstaki works against them.

On 8/3/2023 at 1:59 AM, indyo said:

if beetles, bacillus thuringiensis kurstaki works against them.

B.t. maybe, but not kurstaki, that's specific for lepidoptera, moth larvae. Use that for budworms.

Other strains of B.t. can affect beetle larvae, if you can get them to eat it. 

 

National Pesticide Information Center:

How does Bt work?

Spores made by Bt damage the gut of insect larvae after the larvae eat them.² The insect gut must have a pH of 9.0 to 10.5 (high pH) in order to activate the toxin.^2,10 This is different from the human gut, which has a low pH and is more acidic. The activated toxin breaks down the insect's gut lining. The insect larva dies of infection and starvation.^10,11,12 Death occurs within 1-5 days.^10,12 Young insect larvae are most affected.¹

Each type of Bt toxin is specific to the target insect family.^2,3 Some strains of Bt toxins are also toxic to nematodes.¹

 

Common types of Bt strains:

• Bt israelensis controls immature mosquitos, flies, and gnats.²
• Bt aizawai and Bt kurstaki controls caterpillars of moths and butterflies.²
• Bt tenebrionis and Bt japonensis control beetle larvae.^2,3
• Bt san diego controls beetle larvae.³

look like a good fishing bait !!!