San Jose Scale is a common insect pest that affects various fruit trees, including apple, pear, peach, plum, cherry, and other stone fruit trees. It is caused by the tiny parasitic insect, Quadraspidiotus perniciosus. San Jose Scale is considered a serious threat to fruit production and is widely distributed across temperate regions around the world.
The scale insect appears as a small, round, grayish-brown bump on the branches, twigs, and fruit of infested trees. These bumps are the protective covers beneath which the scale insects feed on the tree sap, depriving the host tree of essential nutrients. Due to their small size, San Jose Scale infestations often go unnoticed until they become more severe and damage the tree.
Infested trees exhibit symptoms such as yellowing leaves, stunted growth, weakened branches, and reduced fruit production. In severe cases, the scales can cause premature dropping of the fruit and weaken the tree, making it more susceptible to other diseases and pests.
Control of San Jose Scale involves applying horticultural oils or insecticides during the dormant stage to kill the overwintering scales. Precise timing and effective coverage are crucial in managing this pest. Regular inspection of the trees and timely intervention are necessary to control and prevent the spread of San Jose Scale.
Implementing integrated pest management strategies, including regular pruning to remove infested branches and proper cultural practices, can help reduce the risk and impact of San Jose Scale infestations on fruit tree growth and yield.
