Fall is here. Leaves display their brilliant colors as September wanes into October. Days shorten in the journey from equinox to solstice as the rising sun creeps south along the horizon from October, through gray November into snowy December. Then it seems to say, enough, halts and turns north once again. Life on the prairie prepares for this long rest during the cold winter in Wisconsin. Animals produce the young of the next generation, then find a way to survive by burrowing underground or into a safe crevice, leaving the scene all together, or just toughing it out. Hibernation, migration, toughness. Plants, of course, are stuck in one place, and must survive by different strategies. The shorter days and colder temperatures somehow signal the plants that the time is ripe to prepare. Most perennials actively lose their leaves and enter their own form of hibernation. Metabolism above ground grinds to a halt, water is shed, while sugars are concentrated into a sort of antifreeze to protect the exposed parts of the plant. The annuals put their faith in the many seeds they disperse into the surroundings. Abscission, dormancy, seed dispersal. All of this in the final act on the prairie. But wait, not all is done quite yet! One of the stars of the final act has just come on stage- the Asters!
Asters bloom much later than most plants on the prairie and are very important sources of food for many insects preparing for winter. Go see for yourself- most of them are covered with a wide variety of native bees! And they are out there in force with many varieties popping up along the road, in fields, and on the prairie. But asters can be tough to identify. They are kind of like the warblers of the birding world that many of us must relearn each year when they come through. Most of the other plants on the prairie emerge in the excitement of spring or summer, commanding our attention and making us eager to identify them as they grow and bloom. But asters come late in the game and might miss our attention as we rake the leaves, tidy up the garden, and take down the flower baskets preparing for our own winter.
But they are too beautiful and important to go unnoticed! And noticing something often involves seeing it in enough detail to being able to identify it. How should this be done for those pesky asters? Well, some start by grouping them into white vs blue/pink/purple. Then, in what habitat they are growing. Next, by looking at the flowers- how wide, how many petals, then the leaves- are they heart-shaped, clasping, do they have teeth, are they hairy? Is the stem hairy? The book, Wildflowers of Wisconsin and the Great Lakes Region by Black and Judziewicz, and the website Minnesota Wildflowers are excellent resources. Eventually, however, it can become second nature and a glance at the overall form mixed with a few details can be enough for identification of many aster species.
Here's one that many of us know and love- the New England aster (with a couple of bumblebees):
Now, here's one for you to try to identify:
A birds eye view:
Height about 42 inches. Stem not hairy:
Flower white with a hint of blue, diameter about 0.5 to 0.75 inch with about 10-12 petals:
Heart-shaped lower leaf about 5 inches long, 2.5 wide, smooth texture:
A magnifying loupe to look for hairs- minimal on central vein:
There are your clues. Maybe stop here, get out your references, and see if you can identify this aster before the answer appears below.
As mentioned above, most asters will have a bunch of native bees foraging on them. Here are two common ones that were on our particular aster.
A metallic green sweat bee, one of the Augochlorini tribe:
Another sweat bee, maybe Halictus ligatus:
So, what is the aster above? It is Commom Blue Heart-Leaved or Wood Aster, Symphyotrichum cordifolium!
Now go out there before it’s too late and enjoy the rest of the asters while they are still in full bloom and feeding all those native bees!