Okay, so the season is winding down for some, but for the American Goldfinch (Spinus tristis), it is just beginning. In Massachusetts, goldfinch nestlings have been recorded from July 28 to September 28.
These beautiful yellow songbirds delay nesting until late summer when thistle, their favorite food, comes into bloom, ensuring an abundant and reliable supply of seeds for their young. Goldfinches also use the down from thistle to line their nests, along with the “fluff” from cattails, willow catkins, dandelions and grasses. They build cup-shaped nests in the vertical fork of a tree or large shrub, often choosing elderberry, maple, willow, dogwood and fruit trees.
Late summer and fall flowering plants are a major food source for goldfinches: sunflowers; marigolds; coreopsis; asters; black-eyed Susans; anise hyssop; globe thistle; and coneflowers. Providing thistle seed or nyjer in a thistle sock (goldfinches love to cling and pick out the seeds one by one) or thistle feeder is also a great help.
Hang the sock or feeder high enough to discourage cats and be sure to provide clean water in a birdbath or fountain nearby. Keep water sources away from shrubs; cats are masters of ambush.
Finally, if you’re interested in creating a habitat for birds, know that burdock is dangerous for goldfinches. While feeding on the seeds, they can become entangled in the burrs and die. Don’t plant burdock and remove any plants you may find. Goldfinches will thank you.