Popis: |
We studied effects of fertilization and time of cutting on the regeneration of cutleaf teasel (Dipsacus laciniatus L.) at the Mascoutin Recreation Area at Clinton Lake, Dewitt County, Illinois, for two growing seasons. D. laciniatus is an exotic European invasive species that infests natural habitats across much of the United States and southern Canada. We established fourteen 5.0-m × 5.0-m paired plots, seven fertilized and seven unfertilized. Each set of paired plots was assigned one of seven cutting treatments, including no cutting, or one of six cutting times from 3 June to 10 August 2002. We measured stem height, number of heads per individual plant, number of seeds per head, and seed viability. We found no significant difference between plant heights or number of heads per individual in fertilized versus unfertilized plots. Reproductive success significantly increased when D. laciniatus had more time to grow after cutting. If cutting occurred before flower buds opened in early July, no sig... |