Scale Insect on Mango Tree
Scales are small, stationary, shell-like insects on leaf, stems or fruit surfaces. They are flat or pear-shaped, white or grey. There are several kinds of scales that can be found on the upper or under surface of leaves. The female scale lays 80-200 eggs depending on temperature. After hatching, up to 80% of the crawlers become males. Their life cycle is 35-40 days in summer or 70-85 days in winter.
Mango scale can be seen all year round because of overlapping generations throughout the year. The pick time is during flowering in spring or in harvest time. Scales can damage trees by feeding from the sap and releasing poison. In the infested area, leaves turn pale green or yellow and ultimately die.
Prune to decrease scale population and to open canopy for spray penetration and sunlight. There are beneficial insects such as ladybugs and lacewing that are natural predators of the young larval or crawler stage.
Spraying systemic pesticides or mineral oil is effective to control scale. Use chemical control when the population is low to prevent population increase and only if monitoring shows significant live scale activity.