Location: Emerging Pests and Pathogens Research
Project Number: 8062-22620-005-02-A
Project Type: Cooperative Agreement
Start Date: Sep 25, 2015
End Date: Sep 24, 2020
1. Document the survival and longevity of spotted and meadow knapweed seed in the soil seed bank, and monitor the population demography of spotted and meadow knapweed in order to understand how various life stages contribute to population growth. 2. Determine the effect of habitat and biocontrol agent damage on plant performance and field densities of black and pale swallow-wort.
1. Seed of spotted and meadow knapweed placed at various soil depths in pots sunken into the ground will be assessed for germination and seed survival rates up to eight years after burial. Monitoring plots will be established within field populations of spotted and meadow knapweed in which individual knapweed plants of different life stages will be mapped/marked and annually censused for survival, growth and fecundity for three years. Soil cores will be taken to assess seed bank numbers. 2. Tagged juvenile plants of pale and black swallow-wort within three habitat types will be annually censused for survival and time to first seed production. Potted swallow-wort plants will be subjected to different densities of insects in combination with plant competition in a quarantine greenhouse. Insect agents approved for release will be mass-reared under quarantine conditions and released into field cages and in the open field. Swallow-wort reproduction and densities, insect damage, and other flora will be monitored.