Insects are amazing. Some are able to stimulate plants to grow a shelter for their developing larvae. These growths on plants known as galls.
After the eggs that are laid on the plant hatch, the larvae start to eat. The chemical compounds they secrete stimulate the unusual plant growth.
Since discovering an additional type of gall in Eliza Howell Park, this seems a good time to showcase several kinds found here. (Kathy Garrett, another Eliza Howell nature enthusiast, called my attention to the fact that the word “gall” is found in the word “gallery.”)
This gall is the most recent find. It is on some Staghorn Sumac shrubs. Inside the galls are developing aphids.
Near the river each summer are patches of tall Cutleaf Coneflowers (also called Green Coneflowers).
At the base of the flower on some of these coneflowers are large galls, made and inhabited by tiny midges.
A fascinating gall is occasionally seen on wild grape vines. It resembles a bunch of filberts or hazelnuts and each is a midge “nest.”
Every year, I find small growths on the midrib of different white oak species. They are present now and will remain until fall. These galls house young wasps.
While most species of goldenrod are not yet blooming, they are growing rapidly. Some stem insect galls can already be seen.
These galls are home to eggs and larvae of a type of fly and are often easier to find in the winter when the leaves — and the larvae — are gone.
The stems of Swamp White Oak or Bur Oak are sometimes the location of a different wasp gall, Oak Bullet Gall.
These wasps are able to stimulate the oak to ooze sweet sap, attracting other insects to patrol the galls and prevent attack by predators.
The last stop on today’s tour of the gall gallery is at photos of blackberry canes, where I often find a small number of large galls on stems. These are also the home of small wasps.
Every year — more like every week — I become more and more impressed by the wonderful world of insects. Tiny unidentified flies and wasps and aphids and midges stimulate the growth of galls — and stimulate as well as my sense of wonder.
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