Archive for the 'Galls' Category

17
Sep
08

Goldrenrod Galls – Sept 17 2008

Here are good examples of insect galls on goldenrod

The top bushy gall is caused by the goldenrod gall gnat which stops further stem growth.

Other galls are the spherical bulges lower on the stem of the plant called goldenrod ball galls.  Created by the gall fly larva, these homes are invaded by birds in the winter like chickadees and downy woodpeckers.  It’s even possible to identify which type of bird ate which larva by the hole that is left on the gall.  These larva are also invaded by ice fisherman who use the larva as bait.

The goldenrod gall moth also produces a gall that is elliptical in shape.  Here’s a how it avoids freezing to death in the winter.

Goldenrod seems to have a difficult life.

If you’re interested in more information I’d suggest “The book of Field and Roadside” by John Eastman.  It’s an excellent resource concerning plants and there common insect associates.

For more on goldenrod galls