Bug Index


 Assassin Bug

Bigeyed Bug

Boreal Firefly




Giant Diving Beetle

Giant Stoneflies

Giant Water Bug

Ground Beetles

Honey Bee


Ladybird Beetle



Pirate Bugs

Praying Mantid

Predatory Mites

Rove Beetles


Syphid Fly

Tachnid Fly

Yellow Jacket



Resembling house flies, tachnid flies are 1/3 to 1/2 inch in length and may be brown, gray or black in color. There are many species, most of which are predators. They eat such pests as: cutworms, codling moths, tent  caterpillars, cabbage loopers, and gypsy moth larvae.These large flies are terrific pest controllers in the garden. 

Adults are identifiable by lots of course bristles covering their abdomens. They resemble houseflies but are usually mottled black, grayish, or brownish instead of brightly colored. Females lay eggs on the bodies of host insects or on plants. The larvae mature inside the unsuspecting host insect, usually killing it. The fully grown larvae then drop from the host and pupate in the soil. 

Tachnid flied prey on a variety of insects including: caterpillars, beetles, sawflies, borers, and green stink bugs - to name a few. These valuable flies can be attracted to the garden by planting flowers and herbs such as dill, parsley and Queen Anne's Lace. They also love spearmint.

Tachinid fly larva is yellow. Females lay their tiny white eggs on or near a host like caterpillars, corn borers, cutworms, sawflies, grasshoppers and armyworms. One survival mechanism is the female can literally glue it's eggs to the host. One female can lay up to 6,000 eggs. They can go through a complete lifecycle in 3 weeks meaning an abundance of garden allies all season. The larva, which is gray to white, then enter the host, feeding off of them, parasitizing them to death. When done feeding the larvae drop to the ground, pupate and emerge as adults in June to September. The tachnid fly is a very important beneficial insect.