Happy Mystery Monday! Can you guess what is pictured in photo #1?
The answer to last week’s mystery is cypress twig gall midge, Taxodiomyia cupressiananassa, pictured in photo #2.
Nope, they’re not pinecones! The spongy, powdery balls encasing the cypress twigs pictured are caused by the larvae of a tiny fly, the cypress twig gall midge. Female twig gall midges lay a cluster of eggs on young cypress leaves. The growing maggots induce the midrib of the leaf to swell into a gall. A single gall can contain a dozen or more larvae.
The galls are most noticeable in late Spring and Summer, appearing as white or greenish-white.
Insecticide is not recommended because the galls do not harm the tree and there is no good, practical treatment for controlling them. Gall midge outbreaks are somewhat sporadic and a tree that was heavily infested with galls one year may have only a few galls in subsequent years.
Mystery Monday is sponsored by the Spy Newspapers and Adkins Arboretum.
Mary Ann Brown says
The insect shown in Monday’s photo is the Milkweed Tussock Moth caterpillar.