Note to readers, attached is the complete final report for FNE94-037.
Each of the materials used in this study succeeded in keeping the understory relatively weed-free. The quackgrass made a quick reappearance in the hay mulch, as expected. The wool mulch postponed the reemergence but quackgrass was visible in four weeks from initial application and continued to push through all summer. The quackgrass under the newspaper/hay was killed by lack of light and physical barrier. In the middle of September the paper had lost its integrity and new rhizomes were able to grow through. The cardboard was effective in killing the quackgrass roots as evidence of dead roots found in the final test pit. The cardboard also prevented the new invasive roots from emerging as they could not push through the cardboard thickness of all three types of cardboard.