Winter Asters 2

by Carl Strang

Yesterday I shared the three species of asters common at Mayslake Forest Preserve that were relatively easy to identify in their winter form. Today’s conclusion focuses on the remaining three species that are relatively common at Mayslake. These were a little trickier. First, I remembered the location of a cluster of a woodland species, the side-flowering aster.

Side-flowering aster in winter.

Side-flowering aster is a woodland species, which helps limit the possibilities as most asters grow in open habitats. I am tempted here to call in a birder’s term, “jizz,” the overall intuitive impression given by a species. This aster has a delicate sprawling appearance. Up close, you can see the feature that gives the species its name.

Side-flowering aster heads are arrayed along the top of the stem.

The heads are oriented upward along the horizontal arrays, so that they are all on one side of the supporting stem.

Side-flowering aster in bloom.

Hm. This photo doesn’t show the array very well. At least you can confirm it’s an aster. Let’s move on. The most challenging identifications were those of panicled and hairy aster. Both have linear or strap-like, stemless leaves, and array their flowers in similar ways. But would the latter’s hairiness persist into winter? After scrutinizing a lot of plants without satisfaction, I went to a place where I remembered seeing hairy asters in bloom. I was relieved to find them distinctive.

I didn’t compress this photo as much as I usually do, so you should be able to see how hairy the stems are.

The stems were hairy indeed. They also were thicker than those of most other aster species, and more of their leaves were holding on among the seed heads. Much more common were the asters I concluded were panicled asters. Like the hairy aster, at least some of their leaves hang onto the stem, mainly among the flowers.

This panicled aster was exceptional in retaining several of its lower leaves. Most have fallen off by mid-winter.

I find myself less confident with this one because I am identifying it mainly by process of elimination. It lacks the distinctive leaves of New England, Drummond’s and heath aster. It grows in open areas and is much more robust than the side-flowering aster. Finally, its stems are smooth to rough but not hairy.

Panicled aster is distinguished mainly by its middle-of-the-road appearance.

Finally, here is a panicled aster as it looks when flowering.

White flowers are common with panicled aster.

In these two posts I have shared the results of my attempts to identify winter asters. I am confident that some of the information is good, but the standard caution that should be applied to information you encounter on the Internet goes double here. If you find this topic interesting, I encourage you to try your own hand at winter plant identification.