I returned to the office this week after a week-long vacation with many questions from homeowners to identify a mysterious disease affecting magnifying trees in their landscape.
A little research led to the conclusion that the trunk and branches were colorful, clustered, distorted growth, and the black, dusty substance on the leaves came to a conclusion – a magnifying glass with mold.
Magnolia (Neolecanium cornuparvum) is one of the largest and most visible insects in the Ohio landscape. Have you ever heard of scales? Although not like most insects that we think will affect trees on the surface, scales are insect-like.
Often on tree branches and trunks a soft and shiny brownish-brown or slightly soft-orange color and a smooth outer layer appear on the branches of the tree. In the pop-up pop-up pop-up pop-up pop-up pop-up pop-up pop-up pop-up pop-up pop-up pop-up pop-up pop-up pop-up pop-up pop-up pop-up pop-up pop-up pop-up.
This type of damage weakens branches and growing branches, impeding growth. Leaf development can also stop the formation of a thin layer. Growing scales are usually covered with white mela wax and can be seen in white color and appearance. A constant diet and severe epidemics can kill a mature tree.
A second problem with insect scales is the secretion of excess vegetable juice as pure adhesive. When the scales are eaten, the tip of the honey drips and coats on nearby leaves and branches, creating an ideal environment for the growth of a black fungus called mildew.
In most cases, soy mildew is considered harmless and even more harmful, but when photosynthesis is a barrier, it can cause problems when it completely covers the surface of the leaf. An infected magnifier can plow anything under it with honeycombs, especially benches, bird baths, garden paintings, and sidewalks. The honeycomb can also attract ants, bees, wasps and flies.
The main target of this pest is various species of magnolia. Sugar, star and lily magnolia species are the most vulnerable and most susceptible to serious outbreaks. Other species, such as the pumpkin tree and southern magnolia, are less likely to be affected by magnolia.
Magnolia measures winter temperatures, such as small, dark neoplasms on shoots that are 1 to 2 years old. In the spring, when the temperature warms and the juice begins to flow, the amount of nephrite begins to melt. The males are small (about 5 inches) and turn white. Women’s scales are large, and in early June they should be brownish-purple and yellow-brown in early summer and covered with white wax.
In late July and August, they are known as adult females. Small movers emerge as mobile and begin to look for a suitable place to eat and stay until winter.
Although there are many predators and parasites known as magnolia, they are often ineffective in suppressing the population.
Magnolia measurement effective control and management involves three main strategies: purchasing pest-free plants, using summer or vegetable oils, and regular chemical control options.
The treatment strategy should be related to the most vulnerable level of insect development. The most effective timing is from the end of August to the beginning of September when visitors are new. Soil wells are also an excellent alternative to control, using systemic pesticides designed for early May control.
See the following resources for more information on Magnolia scale and soft mold
Ohio State University Extension Fact Sheet ENT-61-Magnolia Scale https://ohioline.osu.edu/factsheet/ENT-61
University of Kentucky Extension Intology: ENTFACT-431-Magnolia Scale https://entomology.ca.uky.edu/ef431
Bookmark Yard and Garden Online – Be an Alarm for Magnolia Scale
https://bygl.osu.edu/node/1803
Bookmark Yard and Garden Online – Magnolia scale is squeezing and dripping honey
https://bygl.osu.edu/node/1316
For help with inquiries, contact your local major horticultural volunteer program or the Ohio State University Extension Office.
Visit https://mastergardener.osu.edu/about/ohio-mgv-county-programs to find your local major gardener volunteer program
Visit https://extension.osu.edu/lao#county to find your local extension office.
Heather Nikir is a professor of Star County Extension in Agriculture and Natural Resources for Ohio State University (OSU) Extension. OSU Extension is the distribution arm of the College of Food, Agriculture and Environmental Sciences (CFAES) in each of Ohio’s 88 counties. Contact her at 234-348-6145 or at neikirk.2@osu.edu.