The University of Wisconsin-Madison operates a 1260-acre arboretum that includes areas of prairie, savanna, marshland, and deciduous and coniferous forest. Much of the arboretum has been restored with some 300 species of plants that used to be prevalent in the area before the arrival of European immigrants, including my own ancestors, in the mid-19th century. In my childhood years, annual grandparent visits frequently included a visit to “the arb” – probably for short walks from the Visitor Center in some of the nearby gardens. This time, during a visit with my brother, he suggested a walk in the southern section of the Arboretum, just south of the beltway, with a primary destination of Greene Prairie, a 50-acre prairie planted by prairie expert Henry Greene in the 1940’s and 1950’s.
Although only a relatively short section of the walk was actually in Greene Prairie, the multitude and diversity of the wildflowers made up for the short distance. One of my favorite wildflowers, found near the edge of the prairie near a savanna, was the dotted horsemint (Monarda punctata), which featured swirls of delicately colored, spotted blossoms.
The primary access point for the southern section of the Arboretum is a small parking area immediately next to the beltway: the Grady Tract parking lot, located on land that had previously belonged to the Grady family before the University acquired it. Several walking trails wind through the areas that have been restored to deciduous and coniferous forest, oak savanna, and prairie. Our 2.1-mile loop path is shown in the GPS track image, where the orange dot denotes the parking lot. We traversed the loop clockwise.
The elevation changes are quite gentle, with only about 100 feet separating the low and high elevations and less than 200 total feet of ascent and descent.
As is typical for July in Wisconsin, the day was warm, though I think both the temperature and humidity were below average. Nevertheless, the forest areas were shaded and pleasant to walk through. The trail angles away from the beltline and, although traffic noise was apparent initially, it faded surprisingly quickly as we walked.
Quite early in the walk we encountered a bittersweet nightshade (Solanum dulcamara), with blue-purple petals and a characteristic yellow “beak”.
Our next find was some flowering spurge (Euphorbia corollata). The white petal-like structures are actually bracts, with the tiny flower in the center of the bracts.
In the same area we found some showy tick trefoil (Desmodium canadense). The picture shows the blossoms, which are indeed showy. It turns out that there is another tick trefoil that looks very similar. I have made the identification on the basis of other pictures that show details of the leaves, which have three lobes as suggested by the term trefoil. The showy tick trefoil has stipules – the small structures that occur on some plants at the base of the leaf stem – that have a lanceolate, or pointed, shape. And the leaf stems, or petioles, are shorter than in the other species. This is the first time I’ve made a species identification based on this kind of detail about the plant’s structure – and had the photograph(s) to support my identification!
Near the edge of the forest we encountered a few woodland sunflowers (Helianthus strumosus). It is a wondrous mystery that these flowers, which thrive in a woodland habitat, can find areas that have just the right amount of sunlight. This one was like a bright beacon in a patch of sunlight in the shaded woodland.
Also near the edge of the forest we found some common yarrow (Achillea millefolium). I have seen the same species numerous time and places in California, and it is always interesting to me to find the exact same species thousands of miles away. The Latin species name, millefolium, means thousand leaves. It was also interesting to note that the feathery characteristic of the leaves (see upper right of the picture) was much more pronounced than the yarrow plants I’ve seen on the West Coast.
Other fairly common flowers found in the forest include common St John’s wort (Hypericum perforatum), heal-all (Prunella vulgaris), and wild bergamot (Monarda fistulosa), which was also prevalent in the prairie. We also saw some goldenrod, which I think may be Canada goldenrod (Solidago canadensis); this is a rather tentative identification since there are something like 24 species of goldenrod found in the area and several look quite similar. However, Canada goldenrod may be the most common and widespread of the goldenrod species.
After we had covered about 1 mile we emerged into Greene Prairie and found a wonderful open area chock full of beautiful wildflowers and tall grasses. In this picture the nearby forest is in the background.
Almost immediately I spied a group of Japanese beetles feasting on an unsuspecting, unidentified young budding plant.
A common prairie wildflower, noted on several walks during my visit, was rattlesnake master (Eryngium yuccifolium). The round, compact flower heads are quite distinctive.
Another unusual flower that was prevalent in Greene Prairie is prairie blazing star (Liatris pycnostachya). I had been getting used to seeing flower stalks that bloom sequentially from the bottom to the top, but in this case the flowering proceeds from the top to the bottom of the several-inch-long stalk. This plant belongs to the aster family, which characteristically means the flowers are composites, with ray and disc flowers. The blazing stars – there are several species in Wisconsin – have no ray flowers, only disc flowers. But the most surprising thing is that the wildflowers I have seen in California parks – and also called blazing stars – tend to be bright yellow and look very different from Midwest blazing stars!
A fairly common prairie wildflower is lead plant (Amorpha canescens). The leaf pattern suggests that it is in the pea family, and it is. In fact, it is actually a shrub. Many of the plants we saw seemed to be nearing the end of their blooming cycle; this one was not quite as far along. The individual flowers are quite small, only about 1/8 inch long, with orange anthers.
Along a short section of trail we found several nodding onion (Allium cernuum) plants. With the long naked stems and blossom structure it was easy to identify them as onion, and nodding was a particularly apt description of the flower head cluster.
Nearby and close to each other were two types of prairie clover, both of which bloom from the bottom to the top of the elongated flower head. One was purple prairie clover (Dalea purpurea).
The other was white prairie clover (Dalea candida). Both specimens I photographed had nearly perfect tutus at the base of the flower head.
In the prairie area we also saw a couple of giant, or great, St John’s wort (Hypericum ascyron) and at least one, if not several, types of phlox.
To our delight we found some turk’s-cap lily (Lilium superbum). I seem to especially enjoy the bright color of the recurved petals and sepals (3 each), as well as the fat brown anthers dangling below the petals and sepals. Of course the spots vary from individual to individual flower.
As we approached the edge of the prairie and the transition to savanna area, we found quite a few dotted horsemint (Monarda punctata). The first characteristic I noticed was the distinctive pinkish bracts that occur in several layers up and down the main stem. It was only after I had taken numerous pictures, more or less top-down views, of the bracts that I noticed the rows of smaller blossoms almost hiding between the layers of bracts. These blossoms are shown above, in the first picture in this post. The plant is, indeed, in the mint family, and the blossoms are reminiscent of other mints I have seen elsewhere. I thought this was a fantastic plant.
Near the dotted horsemint there were a few small, bright yellow flowers. I think they are evening primrose (Oenothera sp) though I was unable to make a species identification; there are at least 10 evening primrose species found in Wisconsin and I did not find descriptions for more than one. I should note that the blossoms were not much bigger than 1/2 inch in diameter, much smaller than the most common type of evening primrose in Wisconsin.
After leaving Greene Prairie we walked through a forest area at the west edge of the Arboretum toward the parking area. Along the way we saw a few Deptford pinks (Dianthus armeria) and some yellow wood sorrel (Oxalis stricta). Wood sorrel plants often have clover-like leaves: three leaves, each with two lobes and a visible stem up the center between the lobes. The yellow wood sorrel blossoms are only about 3/8 inch in diameter; the tip of my finger serves as an informal field ruler.
For such a short walk, barely over 2 miles, I was pleasantly surprised at the variety of wildflowers we saw. We had seen some of them on previous walks, but several were new finds, which I always enjoy. As I learn more about the local ecology, I have a growing appreciation for the work done at the Arboretum to restore areas to their pre-settlement state.