Insecticide For Magnolia Scale

Magnolia scale is known to be the most dangerous insect pests affecting magnolia plants. Their scales are a bit tricky to identify as they look like fungus. These insects tend to grow vegetatively on various parts of the tree. They feed on the sap and release vast amount of honeydew. Not only do magnolia scale cause direct damage, but also carry infectious diseases that attack plants. In this article, I will touch upon several tips for using insecticides against these pests and help you get rid of them.

Insecticide For Magnolia Scale

Magnolia scale has become an increasingly common problem on magnolia trees in Wisconsin.  Popular magnolia species such as star magnolia (Magnolia stellata) and saucer magnolia (Magnolia x soulangiana) are very susceptible to this insect.

Appearance: Adult magnolia scale females are shiny brown, elliptical and convex in shape, and up to 1/2 inch in diameter.  They can be mistaken for plant buds on the twigs.  When alive, females are soft and leave a reddish stain when crushed.  Immature magnolia scales are called nymphs and an early mobile nymph stage is called the crawler stage.  Crawlers are yellow to reddish-brown in color and have an elliptical shape, but tend to be more flattened than adults.  As nymphs mature, they secrete a white mealy wax on the outside of their bodies.  This wax tends to disappear by late August.

Symptoms and Effects: Magnolia scale is a soft insect that sucks plant sap, and excretes large amounts of drippy, sticky honeydew.  Honeydew provides an excellent growth medium for sooty mold fungi, and these fungi can give affected leaves and branches a black, sooty appearance.  In addition, honeydew and sooty mold can stain lawn furniture and other items in the vicinity of an infested tree, and sugars in honeydew can attract wasps and ants.  Magnolia scale can also cause slow growth and, on trees that are heavily infested, substantial weakening of branches, branch dieback, and eventual tree death

Life Cycle: Magnolia scale has one generation per year and overwinters as nymphs on one and two year old branches.  Nymphs mature in early June, when adult females begin to lay eggs that hatch in late August.

Control: Control of magnolia scale can be challenging.  Only young, mobile crawlers are easily controlled.  If you decide to use spray treatments for control, select a product that contains bifenthrin, carbaryl, cyflulthrin, horticultural oil, insecticidal soap, malathion, or permethrin.  Proper timing of the application of these products is critical.  Apply spray treatments in late August or early September and follow with a second treatment 10 to 14 days later.  Systemic insecticides, such as those containing imidacloprid, have also been effective in magnolia scale control, but such products must be drenched into the root zone in early May.  Finally, dormant oils can be used for control, but must be applied in March, before buds open.  Be sure to read and follow all label instructions of the insecticide that you select to ensure that you use the insecticide in the safest and most effective manner possible.

Insecticide For Magnolia Scale

Magnolia scale is a sap-sucking insect that is native to Asia. It was introduced to the United States in the early 1900s and has since spread throughout much of the southern states, including California, Texas, Louisiana, and Florida. The magnolia scale typically appears on magnolia trees during the summer months, but it can also be found on other non-magnolia species as well as some conifers.

The magnolia scale is pale yellow-green in color with a circular body and six legs. It prefers warm weather, so it spends most of its life cycle in its egg stage until spring when it matures into an adult female scale. The adult female will begin to feed on the tree and lay eggs that hatch into young scales by late spring or early summer (depending on temperature). These young scales will spend their entire lives feeding on the tree’s sap until they overwinter as adults in late fall or early winter.

Magnolia scales produce honeydew which attracts ants and sooty mold fungus that can damage plants’ leaves and flowers. The honeydew also attracts bees and wasps which pollinate nearby plants while visiting for nectar or protecting their nests from predators.

Insecticides can be used to control this

List Of Insecticide For Magnolia Scale