The tall weed next to Gail with the yellow flowers is Tansy Ragwort. It is an invasive plant unintentionally introduced in Oregon in the 1920's. It is native to Eurasia, and prefers pastures, logged areas, and disturbed ground. It was responsible for killing thousands of cattle and horses until bio controls were implemented in the 60's and 70's.
Cinnabar Moth larvae were brought in from Eurasia as well as a type of flee beetle, and a seed head fly. You can see how the larvae have decimated this flower head. When they run out of food, they eat each other.
Cinnabar Moth larva at work.
Last year, Gail and I pulled up all the flowering Tansy Ragwort along the forest service road we hike on almost daily - about a two mile stretch. We pulled the plants before the flowers matured and threw them on the road to be run over by vehicles. We did this over several weeks just for something to do that we thought might make a difference. This year, the Ragwort is back at least as much as last year. We're leaving it to the caterpillars this time. However, we've only seen the larvae in one small area. The Cinnabar Moth is a pretty red and black. I hope to get pictures soon.
You might remember the little white spider I recently posted. Well, this is another one. They are tiny, about an eighth of an inch long, and hide in flower heads where they ambush pollinators like butterflies and bumblebees.
It is the Goldenrod Crab Spider.
This tiny arachnid uses its large front legs to grab onto its prey and then immobilize it with its venom. It does not use a web. They can change color over several days to match the flowers that it is in. It is very common in the Goldenrod plant, hence its name.
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