As nighttime temperatures dip toward freezing, the trees are starting to show a little color. It’s just the beginning of the most colorful season of the year —
Warm days and cold nights signal plants to cease photosynthesis and begin breaking down the chorophyll pigment in their leaves to unmask other, colorful light-gathering pigments.
Fall weather and decreasing day length signal animals to begin making preparations for winter — either storing food (like the squirrels have been doing) or eating like crazy to get fat enough to migrate south. Waves of warblers and other small songbirds have been moving through the Twin Cities recently, and some wind up in the backyard, looking for insects on late-blooming plants.
Large flocks of Yellow-rumped Warblers move quickly through the vegetation, but occasionally stop to pose for a photo.
Only a few species of perennial plants are still flowering here, like this Showy Goldenrod that is buzzing with several species of insects.
Pollinators looking for a late autumn meal of nectar and/or pollen crowd onto a Showy Goldenrod plant that stands out in a field of Little Bluestem grass. In addition to the bumblebees, two species of hoverfly, a beetle, and a small wasp were foraging here.
New England Aster was buzzing with Pink-edged Sulfur butterflies, bumblebees, and hoverflies.
Seed-eating migrants might find a banquet waiting for them too, as perennial plants put forth their seed crops.
Canada Goldenrod seeds are buried in the wispy tendrils that help disperse the seed around the prairie.
Perennial grass seeds are ripe for the taking as well.
With all the rain late this summer, I hope this will be one of the most colorful fall seasons in recent years. But that depends on the day-night temperature differences in the next few weeks. So, stay tuned for more posts on fall color later.