No, not fresh water. But salt water from oceans or water with soap in it is toxic to caterpillars, which would make them die.
Yes, diatomaceous earth can effectively kill caterpillars by dehydrating and damaging their exoskeletons.
yes
Yes, neem oil is an effective natural insecticide that can kill caterpillars by disrupting their growth and development.
You step on it :D
Because they didnt do anything to you.
No. Explanation: Caterpillars eat leaves which contain a lot of moisture.
You can effectively kill caterpillars on plants by using natural predators like ladybugs or by applying insecticidal soap or neem oil. Make sure to follow the instructions on the product label for best results.
To remove caterpillars without harming them try spraying them away with the garden hose or pick them off by hand. Mix together a teaspoon of dish soap with a half a gallon of water and spray on plants to keep caterpillars from coming back.
if you keep them safe, yes, but if your trying to kill it just step on it.
we kill all the caterpillars, then complain theres no butterflys
Caterpillars eat vegetation. If they are numerous, they can kill plants over wide areas.You're probably not old enough to remember the 'tent caterpillar' problem we had in the northeastern US.
Sure. You could drown them in it; use a full bottle to smash them with... It's not magically extra-special-toxic to caterpillars, though.