As I walk through our parks I am struck at how many things there are that I can’t give a name to! That’s the genesis of this blog series. If I start to learn some of these things, why not share them with the readers of this series? The group (or taxon) that gives me the most trouble is the grasses. They all look the same! And as you walk through your parks, you may notice as I have that there are plenty of similar-looking grasses.
Grasses do look a lot alike, so taxonomists use diagnostic characteristics to tell them apart. Those are distinguishing characteristics, like a certain color in a certain part of the grass or a certain type of seed. But those characteristics won’t make any sense without knowing the parts of a grass. Then one can use what’s called a dichotomous key, which is a tool used to determine the identity of an unknown species by answering a series of questions that are broken down into two choices leading one to the correct species.
And so if you are walking through your parks you may come across the very common grass called barnyard grass (Echinochloa crus-galli (L.) Beauv.) [ECHCG]. Also called panic-grass or watergrass, it is a summer annual that reproduces by seeds that germinate in early spring to mid-summer. It’s part of the Echinochloa crus-galli complex. Taxonomists often include many similar species and varieties into a complex to indicate a high degree of similarity between many species or due to the complexity of the group, but generally it means a group with similar-looking species or varieties.The distinguishing characteristic of barnyard grass is the inflorescence of its spikelet. It is found along ditches and other areas with moist soil. It’s considered a common weed and grows best with rich soils and so is found in disturbed sites with enriched soils. It doesn’t seem to be a pest plant in our parks. It’s part of the complex of species that live along the trails and streams.
Many grasses make up the species of our parks and play very fascinating, complex, and unknown roles. They provide forage for small mammals and mulch after winter has killed them. See the bottom of this post for a quick guide to the different parts that make up a grass plant.The roles of all the species in our parks are constantly unfolding before our eyes. As the seasons come and go, the grasses and other plants change in complex and exact manner and sequence. As you go through the parks, notice how many of the same types of species are in one place. For example, how many species of grasses are in one site versus another site and why? Or how many different species of trees are in one place versus another? Sometimes the answers are obvious–it’s wet or dry, it’s sunny or shady, it’s disturbed or forested. But sometimes it’s baffling!
We have many more plants drying up in the press and will be telling you about more soon. Next up we have ragweed! Many of you know that as the plant that causes hay fever and despise it, but maybe it has some good uses…stay tuned! And remember if you have a picture of a plant you can’t identify please send me a few pictures and tell me where you saw it and I will try to identify it!