Sustainability

Spider chases insect away

Animals that interfere with farming include all those that damage cultivated plants. Most of the farmer's efforts go just into fighting and restraining the innumerable phytophagous animals, mostly insects, but also mites, nematodes, birds, mammals and others that take advantage of the produce grown by man, thus causing remarkable economic damages. Phytophagous animals are all those insects that feed on plants and cause, therefore, irreparable damages to the whole cultivation unless removed or killed before it is too late. Every phytophagous insect has however some natural enemies, which are parasites, predators and micro-organisms that give it diseases. These enemies are used to restrain pests in a way that is safe for both man and the environment and is called "biological fight". For instance, other predatory mites are used to restrain the red spider, a mite that damages cucumbers. The biological fight does not completely destroy the harmful species, but reduces the number of its members. This establishes a balance between the prey and the predator, which allows these plants to grow safely.