On Defining a Weed
| Common Mullein Verbascum thapsus The common mullein, exotic and invasive in our area with a rather plain flower, is a weed by almost any standard. However, the dense basal leaves provide habitat for all sorts of small animals, the fuzzy leaves illustrate a drought-tolerant adaptation, the flower spike attracts many pollinators, and finches feed on the seeds. |
| In planning for maintenance of the Hooker Oak Nature Study Area, we found ourselves facing the question: What is a weed? That is easy to answer. A weed is a plant (perhaps even an animal) where it is not wanted. Unfortunately, the immediate consequence of that answer is a more difficult question.....What do we want?..... where? That leads to a still more basic question.....What is the purpose of a nature study area? Probably everyone who has thought about it has a slightly different concept. I would like to share mine. A nature study area is a place where kids can observe natural things going on. Where a diversity of living organisms can be observed. Where animals can be seen interacting with other animals and with plants. Where a teacher could send a student with a simple question to be answered by first-hand observation. "What different mechanisms disperse seeds?" "Does a particular wildflower grow more vigorously when isolated or crowded?" "Does it make a difference if it is crowded by other individuals of the same species or different species?" "Is there more than one kind of tadpole in the pond?" "How many kinds can you see?" What is the difference between them?" "Do black birds feed differently than starlings?" "What is the purpose of a flower?" "Why are flowers different shapes and colors?" "Do different flowers attract different pollinators?" If we are trying to achieve those goals, we obviously have to create an environment which is suitable for a diversity of life. We must choose plants and a maintenance pattern to support the purpose of the area. If we want the kids to be able to find a variety of seed dispersing mechanisms, we have to include plants like: dandelions with parachute seeds; poppies with explosive seed capsules; foxtails with clinging seeds; raspberries with small armored seeds within a delectable fruit. If we want to attract birds for study, we have to include cover, water, and food. The best cover may be a tangled mass of vines or bushes. Food will include the myriad of seeds produced by annual "weeds", the messy fruits of mulberries and persimmons, the insects living in dense vegetation. If we want to keep chorus frogs (tree frogs) around, we have to have dense patches of vegetation for cover and lots of "bugs" for food. The primary goals of a nature study area may conflict with our usual sense of beauty and order. It is important that the area remain attractive. After all it helps define our school for visitors. But it is more important that it remain interesting (= educational). That is presumably the whole purpose of a school. |
