We came across these galls on a wild rose plant last week, and Eliza insisted I do a blog post about them. So here you go.
Insect galls on prairie wild rose – TNC’s Platte River Prairies, Nebraska.
Galls like this are formed when an insect lays an egg on or in a plant and the feeding of the recently hatched larva stimulates excess growth of plant tissue. The result is that the plant creates a little structure that contains both food and protection for the young larva. The most familiar example of this in prairies is the goldenrod gall, which can be seen in just about any prairie containing goldenrod plants. In this case, a wasp laid eggs on this wild rose (Rosa arkansana) plant and inside each of the resulting galls is a tiny white larva.
More galls on the same plant.
For much more information on galls and the insects that create them on wild rose, click here.
The wind finally let up enough to do some close-up photography last weekend, so I went to a small prairie here in town and wandered a bit. Among numerous curiosities was the abundance of a tiny iridescent fly. I had to try quite a few times to get a decent photo of one. (They kept flying away!)
A tiny fly on milkweed – Lincoln Creek Prairie, Aurora, Nebraska.
Not long after I got the above photo, I was ready to call it a day, and started walking back to the truck. I was hot and tired, but was drawn to a particular patch of milkweed. As I closed in, a small movement caught my eye. It was another of the shiny little flies. But in a bit of beautiful symmetry, it was being eaten by a shiny little spider!