If you walk through parts of the Blue Hills where trees give way to roads or fields, you’ll find goldenrod. Since goldenrod is a native species, you would correctly assume that it provides excellent nutrition to insect pollinators and herbivores. But you might not guess that goldenrod is the host site for a small bug called the goldenrod gall fly (Eurosta solidaginis). The female injects its eggs into the stem. When the larvae hatch, they begin to eat, producing a chemical in their saliva that creates a lump, or ‘gall’ that the larvae will live in. The gall not only provides shelter but food as well.
To find them, visit some of the large stands of goldenrod and check for small lumps on the upper stems. If you check inside you might even find the white larvae.