When water stains appear on your marijuana suddenly, or similar to the spots after the water stain is dry, try to wash it with a watering can. If you can’t wash it off, it is very likely that your marijuana has been infested by leaf miners.
When the leaf miner starts to invade the plant, these tiny larvae will burrow into the leaves, causing many white spots on the leaves, which look like they have been watered too much or burnt.
When they grow up a little bit, the distance of movement will increase. While they swim among the leaves, they eat the plant tissues in the middle of the leaves, forming traces of water flow on the leaves.
These tiny bugs will survive in the middle of the leaves until they enter the nymph or adult stage.
After the marijuana entering the flowering stage is attacked by leaf miners, these channels will turn brown, as if withered.
Leaf miners are not a certain type of insects, but a collective term for insects that can penetrate into leaves.
for example
Larva of Leafminer Moth
Larva of leaf miner
The line image of leaf miner activity in the leaf layer is like a map, so it is also called map worm. The thinner end of the line is where it initially hatched. It will eat all the way to the end. The more it eats, the more food it draws, the wider the drawing will be. Some map worms can emerge all the way to the end, and the trajectory of these larvae. Like a river, their lives flow hurriedly from childhood to a short period of maturity after emergence.
Mature leaf miners lay their eggs on the leaves, usually near the veins. After the eggs hatch, the larvae burrow into the leaves and eat the material in the leaves. This is indeed a very successful reproduction strategy. The larvae can avoid natural enemies. And the attention of careless growers. The larva can be seen hiding in the leaf through the sun, and it bites out a space around it. This is the home of the leaf miner larva. They will enter the next life stage quietly in this space.
Prevention method
- The most effective way is to prevent adult insects from approaching your cannabis. Use insecticidal lamps and insect nets to isolate adult insects, which can effectively prevent leaf miners from entering.
- Pyrethroid insecticides and abamectin insecticides, these two agents can penetrate the leaves and kill the leaf miner larvae in the leaves.
- Put the leaf under the light, spot the position of the leaf miner, and pinch it to death with your hands.
- Set up sticky boards in the planting space to stick all kinds of leaf miners.
In general, the control of leaf miners is to prevent adults from laying eggs on plants, and it is not difficult to control these adults. The leaf miner larvae are not very harmful and will not cause fatal damage to hemp, and their mobility and transmission ability are not strong. If there are a lot of leaf miner tracks in the leaves, just pick the leaves and throw them away.