Certain scale species, for instance, are more likely to infest trees and shrubs, while others are more comfortable making a feast out of common houseplants. Scale insects vary dramatically in appearance, from very small organisms (1–2 mm) that grow beneath wax covers (some shaped like oysters, others like mussel shells), to shiny pearl-like objects (about 5 mm), to animals covered with mealy wax. Crawlers are small (<1/32”) and flattened, looking like dust on the plant surface.   Male soft scale appears grayish to white and can look similar to mealybugs. Examples of trees and shrubs that can become infested with scale are arborvitae, azalea, birch, boxelder, euonymus, honeylocust, juniper, magnolia, oak, pine, yew, and many others. Scale infestations spread when crawlers walk or are blown by the wind to nearby plants or plant parts. In Florida, black scale is found on citrus (Citrus spp. It is more prevalent in non-coastal areas than along the coast. Description, life cycle, damage and control options. Each species of scale has specific plants they are associated with. Rosen et al. ), and many popular landscape plants. (1971) reported damage on olive trees in Israel due to outbreaks of the black scale. Whitish or yellowish patches on leaves, stems, or branches is a common sign. Originally from South Africa, this scale is now distributed worldwide. Soft scale damages the plant by sucking sap from the plant. Scale insects feed on leaves or branches of many ornamental plants grown in landscapes and nurseries. Over time, the plant can become more chlorotic-looking, and new plant growth can be stunted. Scale bugs attack a variety of plant life, and different species target different types of plants. If not treated, your plants are at risk of numerous plant diseases or branch death. Scale range in size from one to five millimeters and, in certain life stages, can be difficult to see without magnification. Adult females are almost always immobile (apart from mealybugs) and permanently attached to the plant on which they are … Heavily infested plants are often covered with small, disklike or waxy coverings, and underneath each covering is the scale organism feeding on the juices of the plant. Plant architecture is an important feature for scale host selection and it appears that the black scale prefers trees with dense branching, especially when the trees are planted close together. It also leaves behind a sticky excretion called honeydew. It is one of several pests that can affect hibiscus. How to Deal with a Scale … After an armored scale crawler begins to feed, it becomes very flat and covered with a clear wax shell. They attach themselves to a plant and feed by sucking fluids through straw-like mouthparts. A plant which is suffering from scale infestation may show signs of premature leaf drop or yellowed leaves. Black scale (Saissetia oleae) is classified as a soft, plant-sucking scale insect. ), cultivated olive (Olea europaea L.), avocado (Persea americana Mill. The azalea bark scale has been recorded in the eastern United States and also in Belgium, Germany, and Russia. Black scale is a major citrus pest in Southern California but occurs only occasionally on citrus in the San Joaquin Valley, mostly on grapefruit or on trees near olives. Black scale (Saissetia oleae) insect pest of olives, citrus and gardenia, distributed throughout Queensland. Host Plants: – These insects have been found on more than twenty different plant species including blueberry, andromeda, arborvitae, azalea, hackberry, hawthorn , maple, poplar, rhododendron, sweetgum and willow. Introduction. Animal biosecurity and welfare Plant biosecurity Invasive plants and animals Enhancing biosecurity capability and capacity in Queensland Biosecurity policy, legislation and regulation When scales feed underneath the leaves, yellow spots often appear on the tops of the foliage. The black scale, Saissetia oleae (Olivier 1791) (Hemiptera: Coccidae) is an important pest of citrus and olive trees. The scale blends in well, so the actual insect may not be very apparent. Weakened plants may lose vigor and become more susceptible to injury caused by drought, severe winters, attack by other insects, or infection by diseases.