Spring is considered the best time for woodland wildflowers, when the forest floor is still flooded with sunlight. A few woodland wildflowers wait until late summer to make their appearance, though. They tend to be taller, with lots more leaf surface to capture the sunlight that still filters through the canopy of tree leaves. A recent walk through Hertz Woods just south of Nevada on 11th Street rewarded me with a nice display of several late-blooming species. Areas that benefitted from brush clearing work earlier this year had the most flowers. They included lots of bright yellow Jerusalem artichoke, a sunflower with large, rough leaves. It’s roots have finger-sized tubers that are quite edible and are similar to potatoes. Please don’t dig up any of our lovely parks or preserves to harvest them, though. Also present in more limited numbers were some yellow giant hyssops, a tall square-stemmed mint with a terminal cluster of pale yellow flowers. The yellows contrasted nicely with stands of blue tall bellflower. The latter is also known as crane’s bill for the long, gently curved pistil structure in the flower’s center. White snakeroot was also present in several areas with its little white cotton ball flowers. Goldenrods and some woodland asters will soon join the show.
Most of the wild fruit is done for the year, but some of our woodland edges offer tasty wild plums. Wild plums are smaller than their domestic cousins at little more than an inch in diameter. They don’t get to that deep purple color, either, but ripen to yellow or orange-red. The skins are tougher, but the golden yellow pulp around the central pit is just as juicy and sweet, if not sweeter than, their domestic kin. I used to pluck a few to snack on right from the mower seat as I mowed by some plum thickets at McFarland Park years ago.
Most grasses need lots of sunlight to thrive, but a couple of species are adapted to woodlands where enough light still filters in. Bottlebrush grass and Virginia wild rye were both heading out along the paths at Hertz Woods. Bottlebrush gets its name from its unique seed head with long-awned seeds sticking straight out from all sides just like a bottlebrush. Good stands of bottlebrush grass are kind of rare since most of it was grazed out long ago when the majority of our woodlands were grazed tight to the ground all summer long. Finding it is a good indicator that the woodland where it is growing wasn’t grazed heavily and probably hasn’t been grazed in many years. Indicator plants like that tell us that an area is probably worth visits at other times of the year when more uncommon plants might still be found.
Although late summer and fall woodlands offer their own special charms, it’s the prairies that attract the most wildflower attention this time of year. Many species of grasses and flowers are blooming right now on native remnants like Doolittle Praire south of Story City and Pohl Prairie just west of the Ames High School. Planted prairies like those at many of our parks and along some of our highways also wait until mid to late summer for their most spectacular displays. Several species of blazing stars (Liatris) grow in Iowa prairies and are among people’s favorites with their wands of delicate lavender flowers. Few plants are more popular with butterflies and other insects, either. A variety of sunflowers join tall compass plants with their yellow flowers waving as much as six feet high. Blue and white asters of several species will soon join them. White flat-topped clusters of mountain mint also attract lots of insects
Tall prairie grasses wait until late summer to send up their colorful seed heads. Big bluestem is a dominant on most central Iowa prairies (especially if they were burned in the spring) with its reddish purple "turkey foot" seed heads waving head-high or taller. Indiangrass is best seen at sunset, when its plume-like seed heads shine like new copper pennies.
You may need to wear long pants and put on some insect repellant, especially if you take a wildflower walk in the evening. Don’t wait until next spring to enjoy our wildflowers, though. You’ll miss some spectacular displays of interesting native plants if you do.