|Goldenrod Ball Galls|
Here is a picture of a Goldenrod Gall Fly larva snug in its home/pantry.
Notably, the larva excavates an escape tunnel (see a picture of the larva's escape tunnel here) to just below the gall's exterior skin. The larva does this in the fall, then overwinters in the center of the gall. During the winter it survives multiple freeze/thaw events. In the spring the larva pupates. When the young goldenrod plants are growing the gall fly hatches, crawls up its tunnel, inflates its face balloon (ptilinum - see a few pictures here, or here), pops open its escape hatch, and enters the goldenrod patch to find a mate in order to ensure the process is repeated.
|Goldenrod Gall Fly - Eurosta solidaginis|
However, there's a good chance a parasitic wasp may emerge from a gall in the spring instead of the gall fly since many of the galls are parasitized. Also, Chickadees and woodpeckers are often seen (and heard) extracting the gall's inhabitants.
Ball galls can vary in size.
Some stem galls are not round but elliptical spindle-shaped, these are caused by moth caterpillars.
There are several species that cause these galls like Epiblema spp. and Gnorimoschema gallaesolidaginis. I believe the latter species was the maker of the gall pictured below. The photo below shows the cross section of a gall of the Goldenrod Elliptical Gall Moth and its empty pupal case.
In the photo below there are "bunches" of bunch galls. These leafy clumps on the mains stem are home to goldenrod bunch gall midges.
|Goldenrod bunch galls|
Another kind of goldenrod bunch gall is pictured below.
Here is one of those bunch galls with an empty pupal case.
Many other insects are found in the bunch galls alongside the gallmakers or their parasites. These fellow campers, or, "inquilines" make themselves right at home in the leafy galls.
The picture below of "Goldierod and the Three Galls" illustrates the the three gall types I've mentioned.
At the risk of being galling, here are a couple more examples of galls associated with goldenrod.
These minute galls look like green seeds among the goldenrod's flowers..
I believe they are Beaked Flower Galls caused by Schizomyia racemicola. I found them growing in the little goldenrod patch in our fencerow.
An orange larva is visible through the hole.
Here is a picture of the little guy through the hand lens.
For me, one of the most fascinating goldenrod galls is the Black Blister Gall caused by a gall midge - Asteromyia carbonifera.
Just think...the midge lays an egg and also infects the leaf with its fungus....
Ah, but this is just a sneak peek.
A quick stroll through the patch.
With all the gall makers, the inquilines, and the parasites, the goldenrod patch is an ecological goldmineWhat a great place to be galling!