Club Root is neither a fungus nor a bacterium and so has an odd lifecycle. It stays as resting spores in the soil until conditions are met where it germinates to produce swimming swarm spores that seek out roots where they enter through the root hairs. Once inside the roothairs, they produce a different type of swarm spore until the hair bursts and the swarm spores infect other parts of the root causing the swelling and distortion. Resting spores are then produced in the swellings to be released into the soil. Clubroot is a common disease of Cabbages, Broccoli, Cauliflower, Brussels Sprouts, Radishes, Turnips, Stocks, Wallflowers and other plants in the Brassicaceae family.