Cottony camellia scale
Also see Armored (hard scales) for additional scale insects.
Soft scales:
Soft Scales Found on Trees and Shrubs - The following are examples of commonly found scale insects that infest deciduous, broadleaf, and evergreen plants.
A scale infestation is indicated by sooty mold on leaves, yellowing of leaves, and twig dieback. This scale is most obvious from May through June when white egg sacs may be found in twig forks. Heavy infestations over several seasons may kill plants. Overwintering immature scales (nymphs) are about 2 mm long, gray, and are usually found in twig forks. This scale primarily attacks azalea and rhododendron but has also been found on andromeda, maple, arborvitae, willow, poplar, and hackberry. There are 2 generations a year in Maryland.
![]() Cottony taxus scale on yew |
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![]() Cottony maple scale |
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A native soft scale that feeds on different species of shade trees, including maple, hawthorn, dogwood, sycamore, and linden.
Fruit lecanium scale
Fruit lecanium scale on twig
Photo:Bugwood.org
Contrary to its name this is a native scale. It has a varied host range but prefers maples, oaks, and ornamental fruit trees.
Preferred host is American elm but will infest Zelkova.
Indian wax scale covering
Has a large host range which includes Chinese
and Japanese hollies, euonymus, spirea, and boxwood.
A difficult scale to control. Pruning out infested stems
and branches and gently scraping the scale
covers off bark are recommended.
A native soft scale with a wide range of host plants. They include dogwood, magnolia, maple, oak, redbud, and many others.
This native scale is one of the largest in size. It feeds only on magnolias.
A native soft scale that can be found on evergreens like arborvitae, yew, and possibly on juniper and cypress.
Pine tortoise scale differs from other scale insects that occur on pine. Mature female covers are 1/4 inch long, hemispherical and dark brown to black with light brown to cream colored mottling. Males are small and inconspicuous. This soft scale attacks Scotch, jack, Virginia, Austrian, Swiss mountain, red, white loblolly, shortleaf, slash and Chinese pines. It has one generation and overwinters as immatures on twigs. The damage symptoms first appear as honeydew, followed by sooty mold build up on branches. Needles turn yellow and branches eventually die. Small pines on exposed sites may are most susceptible and may be killed. To monitor for this pest, look for ants (seeking honeydew), honeydew, and sooty mold near branch terminals. In the spring the large females are found at the base of needles on twigs. Crawlers usually hatch the last two weeks of June.
Main host is Norway spruce but will infest other types of spruce. Similar looking to the buds of spruce trees so they often go undetected. They are often clustered in groups at the base of new growth.
![]() Dieback on shrub from scale insects |
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![]() Sooty mold on yew |
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Scale insects are difficult to control. To manage a scale infestation, prune out branches with severe symptoms. Parasites generally provide control of many scale infestations. To protect parasites, avoid spraying with insecticides during the summer. If treatment is necessary, spray the tree with a dormant rate of horticultural oil during the dormant season to control overwintering scales. Also keep trees and shrubs watered during droughty periods and do not overfertilize.