|
|
Learning Landscapes |
|
|
|
Learning Landscapes |
|
Controlling weeds poses a special dilemma because, once a weed infestation is identified, it is often already so large that containment is difficult and expensive. Biological control (using organisms such as introduced insects or diseases to suppress populations) is effective in slowing the spread of weeds but generally cannot eradicate the infestation. Manually pulling weeds or using machines to dig them up is effective with smaller infestations if done carefully to avoid spreading seeds. Herbicides can be effective in controlling weeds and stopping their spread especially when infestations are detected early. Land managers generally take an integrated approach, using a combination of these methods.
A special emphasis is placed on early detection of infestations and prevention of new infestations. Educated citizens who can report these new, small infestations will make a major difference in the national effort to control the spread of invasive weeds.
Combining educational programs focusing on invasive weeds with weed eradication efforts is one way to help students learn to identify invasive weeds in their community and to help eradicate the weeds at the same time. One such program, Scotch Thistle Days, was hosted annually by the Bureau of Land Management, The Forest Service and other organizations in central Utah. Each spring for 6 years, about 200 junior high and high school students divided into small groups and spent a day digging and cutting Scotch thistle plants in a remote area. There they learned about - and saw for themselves - the ecological impacts of invasive weeds to the surrounding wildlands. After 6 years, the student volunteers were no longer needed. The program is being continued, however, for its educational value.
While field work is perhaps the most effective way to teach students about invasive weeds, there are a number of classroom activities that can also be used to introduce the topic. Studying invasive weeds will complement units on ecological systems, plant reproduction, or native versus non-native species. Lessons on weeds invasions can illustrate for students how the interrelationships of elements in a natural functioning ecosystem can be thrown out-of-balance by an invading species, what the consequences of that can be, and what can be done about it.
