13 September 2025

We’ve entered Seed Season in which late summer flowers set seed just in time for migrating sparrows and finches to eat them.

At top, wild bergamot’s (Monarda fistulosa) petals are gone and the central disc looks like a cluster of tiny pipes. American goldfinches have been busy pulling seeds out of them so the pipes may be empty by now.

Below, in Schenley Park I found pilewort a.k.a. American burnweed (Erechtites hieraciifolius) sporting both seeds and flowers. The flowers are tight green bundles with pistils and anthers protruding. The seeds are on filaments than float on the wind like dandelion fluff.

Pilewort is a native annual in the Aster family that loves disturbed soil and, according to Wikipedia, “is most abundant in areas that have been extensively disturbed, like where severe fire, timber harvest, or bulldozing has occurred.” This big clump of pilewort is growing in bulldozed debris.

At Sewickley Heights Park masses of bearded beggarticks (Bidens aristosa) glow in full bloom along the Pipeline Trail.

When they go to seed they’ll be annoying if you brush against them. Their seeds are the classic “hitchhikers” that latch easily onto your clothing.