Tobacco Budworm is a serious pest of many garden flowers, cotton, tobacco, cannabis and hemp. It is closely related to the Corn Earworm (Heliothis zea) and feeds on flower buds and ovaries, leaving them mangled or completely bored out. Adult moths are usually light green with some appearing browner or tan in color. Larvae, the damaging stage, vary from greenish-yellow and reddish-brown or even black with paler stripes running lengthwise on the body. Tobacco budworm eggs are spherical with a flattened base and white or cream color. The eggs are laid on blossoms, fruit and terminal growth where hatched larvae have easy access to food.
Damage: Larvae hollow out buds, leaving behind molted skins and feces. Their entrance holes and the residue contained in them can invite diseases like rot, spoiling the crop. Later season damage results in fruit being made unusable. Where buds/fruit are limited, budworms will also feed on foliage.
Controlling Tobacco Budworms: Control options are limited and timing of treatments is essential to minimizing damage.
- Release Trichogramma moth egg parasites (especially T. pretiosum) at the first sign of adult moths. Repeat releases while adults remain active.
- Applications of Bacillus thuringiensis kurstaki (DiPel, Thuricide) will kill caterpillars once ingested; however, timing these applications for optimal control can be difficult on crops where the budworms enter buds or fruit.
- General predators like ladybugs, assassin bugs and green lacewing are known to feed on corn earworm eggs, making them a possible biological control for tobacco budworm eggs.