Along State Route 315 in Delaware, Ohio is a nursery that apparently occupies a larger tract of land than needed for their commercial plant-growing purposes, so they planted a nice assemblage of native and almost-native prairie species there for us to enjoy as we travel that pleasant road. One of them is compassplant, Silphium laciniatum (Asteraceae), a huge, dramatic, and long-lived perennial that, while a signature element of tallgrass prairie in much of the midwest, might not be native this far east. (The single putative Ohio compassplant station, in the far south-centrally located Lawrence County, has a history suggestive of an accidental introduction. We do, however, have oodles of prairie dock, S. terebinthinaceum, which is just as good.)  

 

Indeed, this hardy warm-season grass, especially productive even on marginal sites, is being developed as a bio-energy crop, mainly for the production of ethanol. Because it is a naturally occuring species that now has "cultivar" genotypes which might have ecological properties different than those in the native populations, researchers at the Ohio State University are hard at work investigating the potential for gene flow from the cultivated plants to native prairies. Today I visited a test plot where a variety of switchgrass plants are being grown for gene flow experiments, and saw that some of the plants are in flower.

Switchgass (Panicum virgatum) flowers, like those of all grasses, are tiny. The perianth (sepals and petals) are reduced to two tiny swellings that push open a little pair of leaf-like bracts (a lemma and a palea) that enclose the sexual parts of the flower. Being wind-pollinated, grass flowers lack showy parts. The pollen-producing anthers are pendent, held by slender flexible filaments that enable the pollen to be cast into the breeze. Plumose stigmas serve as excellent wind-borne pollen-snaggers.

The bulrush genus Scirpus consists of tall, tufted sedges with many small cone-like spikelets arranged in a terminal cyme. They look fluffy! There are 8 species in Ohio, all native. While they all have bristles surrounding their achenes, two of them have especially long bristles, so they look especially fluffy!! These are wool-grass, Scirpus cyperinus, and stalked bulrush, S. pedicellatus.

Here they are together, slightly "posed." (The S. cyperinus on the left was plucked and carried over to be held next to the S. pedicellatus.)

This isn't the evil invasive purple loosetrife. It's lovely winged loosestrife, Lythrum alatum (Lythraceae), a delicate native plant occasionally seen in wet prairies, marshes, fens, and along shores of ponds.

Winged loosetrife flowers typically have 6 petals (unusual for a non-monocot!) and six stamens. Winged loosetrife illustrates an unusual flower variability called "heterostyly" that is found in only a few species. 


The flowers come in two different types distinguished by the length of the style (the upper portion of the female part of the flower, i.e., the pistil).

The long-styled "pin" flowers have six short stamens, located within the throat of the flower.

An individual plant bears only one type of flower, and pollen from one type of flower is unable to fertilize flowers of the same type as its own. Thus the plants are not merely self-incompatable, but they are incompatable with half of the plants in the population!

The particular type of heterostyly exhibited by winged loosetrife, wherein there are two style morphs, is "distyly." Other members of the genus, including the evil purple loosetrife, Lythrum salicaria, have an even more intricate "tristylous" heterostyly. This was of great interest to an obscure 19th century biologist named Charles Darwin.

The 2010 Ohio Botanical Symposium, held in late March, was awesome and fun and informative. We marvelled at the best botanical finds of 2009, gasped in horror at the status of the hemlock wooly adelgid, found out why there are so many sedges in Ohio (and elsewhere), explored the secrets of pollination, and followed in the footsteps of E. Lucy Braun though the restoration of Agave Ridge Prairie.

Among the highest of the highlights of the Symposium was the keynote speech, "Bringing Nature Home," by University of Delaware Professor Douglas W. Tallamy, author of a book by that name, subtitled "How You Can Sustain Wildlife With Native Plants." This address was a transformative experience for many in the audience, and, more to the point, for their suburban lawns.


Dr. Tallamy, an entomologist, explained that wildlife diversity in North America could be enhanced tremendously if the vast acreage covered by suburban lawns and gardens were more productive of insects. Here's how he so aptly puts it on his informative web site http://www.plantanative.com/


...and it could be incredibly annoying to our neighbors to have a big "weed patch," so let's do it!

Here's a shot taken from an upstairs window looking down on a very boring backyard just a few weeks after the Symposium. If you look closely, you might be able to make out some thin stakes set a few feet apart. These stakes mark the boundary of of our future BNH Garden!