Brittany Teller

EFFECTS OF MANAGEMENT ON GARLIC MUSTARD (ALLIARIA PETIOLATA) FITNESS. Brittany Teller¹, Tiffany Knight¹, Ecology Department, Washington University, St. Louis, MO¹.

Garlic Mustard (Alliaria petiolata), an invasive plant species, increasingly threatens forest and woodland understories where it outcompetes native species in Missouri and in many similar areas of the midwest and plains states. The most non-toxic and reliable way to remove garlic mustard is by manually removing the plant and its root system from its stand. However, this process is often subject to human error that affects both the survival and reproductive success of the target garlic mustard to an extent that was previously unknown.

In this study, six similar garlic mustard plants were subjected to one of six treatments inspired by human error in early and late treatments with fifty replications. Plants were either: pulled completely and left in the original stand, clipped at 50% early and late, clipped at base early and late, or subjected to a control treatment. The treated plants were monitored throughout the growing season and were finally harvested to measure average seed weight and number of seeds produced.

Garlic mustard plants that were pulled and left lying above their original stand produced just as many fruits as control plants at half the weight. Plants that were clipped at 50% early in the growing season continued to grow and produced fewer seeds at lower seedweight than the control plants. All other monitored plants, such as those that were clipped at the base or clipped at 50% late in the season, did not produce new fruits and died, assuming that the reproductive parts of those plants were disposed of properly. Future research will examine and compare germination rates of the aforementioned seeds.