The southern red mite is considered by some to be the most significant and widespread spider mite pest of broad-leaved evergreens, primarily plants in the Ericaceae and Aquifoliaceae families. While it was first described in North America, it may be native to parts of Asia. The southern red mite is known at least from the United States, Brazil, Italy, Japan, Korea, the Netherlands, and Paraguay. It is considered widespread on broad-leaved evergreens in the eastern United States. The mite overwinters as red eggs on host plant leaf undersides. If the mites are not managed, by the summertime eggs become very abundant. Summertime eggs are a darker red than those found in the winter. Multiple generations can occur per year; however the southern red mite may be most abundant during periods of cooler weather. Therefore, population densities can be the most abundant in the spring and fall. Prolonged periods of high humidity also favor the southern red mite. During the height of the heat of summer, most of the population is in aestivation (a summer time dormancy) in the egg stage (Johnson and Lyon, 1991). Adult males and females are similar in size, with females being slightly bigger (approximately the size of a period). Both require magnification to see, such as a hand lens. Southern red mites are reddish brown and darker in color than most other common spider mites, with translucent coloration on the body nearest the head.
The southern red mite feeds on the undersides of host plant leaves. This feeding causes bronzed or stippled foliage. On occasion, it is possible for leaves to become distorted if they are fed upon while young and still expanding. It is primarily a pest of azaleas and camellias. Some sources report that populations of southern red mite may disappear when new spring growth develops.
A hand lens may be required to detect the presence of southern red mites during cooler parts of the growing season, particularly with high humidity. Look for the mites themselves, eggs, cast or shed skins, and webbing. Look for damage to the foliage, such as stippling or bronzing that is visible from the upper side of the leaf. Another technique for monitoring also includes shaking foliage over a white piece of paper or other similar surface. This makes seeing the mites easier, even with magnification. With the naked eye, the southern red mite may look like tiny, red dots (about the size of a period) moving on the paper. Focus scouting efforts during the spring and the fall and plan management accordingly.
Syringing, or spraying mite infested foliage with a heavy stream of water, may help knock the spider mites off their host and provide management on ornamental/specimen trees or shrubs. If done on a regular basis, syringing can have the same effect as strong rain events which help dislodge the mites and reduce the severity of their feeding. This option will not reverse feeding damage (bronzing) that has already occurred.
Populations of southern red mite can be impacted by natural predators. Of those, some information is known about their predatory mite (Phytoseiidae) natural enemies. Laboratory studies of Iphiseiodes zuluagai, Euseius citrifolius, and Amblyseius herbicolus have been conducted and revealed that the adult female life stage of each of those species are the most effective at eating the southern red mite, prefering to feed on their larvae. However, the nymph, adult male, and larval life stages of each of the predatory mites will also feed on southern red mite (Franco et al., 2007). Much of this research, however, has been done in the context of coffee plants. In Brazil, the southern red mite is known as the coffee red spider mite.
Abamectin (NL)
Acephate (NL)
Beauveria bassiana (NL)
Bifenthrin (NL)
Chlorpyrifos (N)
Chromobacterium subtsugae (NL)
Cypermethrin (NL)
Etoxazole (N)
Fenazaquin (NL)
Gamma-cyhalothrin (L)
Hexythiazox (NL)
Horticultural oil (L)
Insecticidal soap (NL)
Lambda-cyhalothrin (L)
Malathion (L)
Metarhizium anisopliae (robertii) (NL)
Neem oil (NL)
Spinosad (NL)
Spiromesifen (L)
Tau-fluvalinate (NL)
Active ingredients that may be applied systemically include: Abamectin (injection), acephate (injection), Metarhizium anisopliae (robertii) (soil drench), and neem oil (soil drench).
When used in a nursery setting, chlorpyrifos is for quarantine use only.
Make insecticide applications after bloom to protect pollinators. Applications at times of the day and temperatures when pollinators are less likely to be active can also reduce the risk of impacting their populations.
Note: Beginning July 1, 2022, neonicotinoid insecticides are classified as state restricted use for use on tree and shrub insect pests in Massachusetts. For more information, visit the MA Department of Agricultural Resources Pesticide Program.
