Definition - What does Parasite mean?
A parasite is an organism that lives on another organism and derives all of its nutrients at the expense of the host.
Parasites can be a huge problem for gardeners and come in a variety of forms.
MaximumYield explains Parasite
A parasitic plant should not be confused with an epiphyte plant. Although epiphytic in nature, a parasitic plant does not harmlessly grow on the host plant and derive all of its nutrients atmospherically. A parasitic plant gains all of its nutrients off the host plant and can kill it if left the plant is left untreated.
There are around 4,100 known parasitic plant species in the world and most will attach and attack another specific species of plant. Parasitic plants are known to be very discriminatory with the species they infect. The Colorado wildflower pterospora andromedea, for example, is frequently the only victim of the parasitic fungi of mycorrhizae.
There are also parasitic insects. The most common and prevalent of these are aphids, which can infect nearly any plant. Parasitic wasps, moths, and worms are also major problems for gardeners and agribusinesses.
Although known as the cabbage moth, this parasitic insect can infect and destroy entire fields of all cold crops.
There are many treatments for parasitic insects, including anything from a simple washing of a houseplant in order to remove aphids, to a wide selection of commercial insecticides.