Submitted to: Concise Encyclopedia of Temperate Zone Tree Fruits
Publication Type: Popular Publication
Publication Acceptance Date: 9/12/2002
Publication Date: N/A
Technical Abstract: A pest is considered to be an organism in direct competition with humans for a valued resource. Pests have the potential to lower yields and reduce marketability of agricultural products. There are five categories of pests that can cause economically important damage in orchard ecosystems: arthropods, disease-causing pathogens, nematodes, vertebrates, and weeds. A particular type of damage can be caused by a single organism or by interactions between several organisms such as arthropod- or nematode- vectored diseases. Ultimately, damage in a particular orchard ecosystem is caused by organisms belonging to all categories, leading to economic losses.