The Bull Creek Foundation, in partnership with A Rocha, is using the summer sun to help eliminate a patch of invasive grass in a meadow near Bull Creek. At our June work day, volunteers met at the Stenis Tract to spread thick plastic sheeting over 38 square meters of invasive King Ranch bluestem grass. We are testing the effectiveness of solarization: using transparent plastic and ground moisture to trap the sun’s radiation and raise the temperature of the plant material and soil that is covered. In effect, solarization creates a ground-level greenhouse. In this case, the goal is destroy plants, not nurture them.
Previous work, including a Girl Scout Gold Award project, showed that manually pulling King Ranch bluestem followed by reseeding with native plants is effective. Ideally, solarization will also show good results while being much less labor intensive.
King Ranch bluestem grass, which is native to China, has spread widely across the U.S. since its introduction in the late 1930’s. It grows rapidly, reducing the diversity of native plants. That, in turn, reduces the diversity and numbers of wildlife.
Solarization with transparent plastic works well under full sun. Covering invasive plants with black plastic can be more effective in shaded areas. Instead of overheating the plants, black plastic kills undesirable plants by starving them of sunlight.