What insecticide is best for killing tent caterpillars?

Bacillus thuringiensis or neem as botanicals and acephate or carbaryl as synthetics are best for killing tent caterpillars.

Specifically, Bt can be effective against the younger instars of the caterpillar stage of the moth in question (Malacosoma americanum) whereas neem efficiently controls older members of the tree-defoliating larvae. Chemical, non-organic, synthetic insecticides which contain acephate or carbaryl as active ingredients will eliminate the defoliating consequences of the invasion but without the more environmentally friendly after and side effects of botanicals. Treatments whose active ingredients include malathion or methoxychlor ratchet the environmental impact up further even though they also get the job done.