| Roger Batt and Jeffrey Pettingill discuss the biolological control agent available for Musk Thistle. Jeffrey believes the bugs were first released in the early 1970's, but not in this location. He notes that it has managed to migrate everywhere when it gets older as a flying beetle, and almost every flower in the top of these plants will have the bug in there. They find a live Rhinocyllus beetle on a rosette on the ground and get one on Roger's hand where the camera can see it. Jeffrey notes that the bugs hatch in the soil and when the Musk Thistle seeds are germinated they will climb up the stem and mate, deposit their eggs in the base of the flower and the pupa will hatch and crawl up into the flower and start eating. They will eat the flowers at the top of the stem, but not the ones lower down. The implication is that the seeds from the lower flowers will produce seeds that will allow the bugs to have a food supply next year. Jeffrey says this is "Population Dynamics."
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