Why do the leaves of the umbrella tree produce oil?

main reason

Insect pests, to be more precise, are caused by the excrement of scale insects.

feature

This kind of insect reproduces very quickly and reproduces a large number at a time. This is not difficult to understand. If there are only a few of them, it is impossible to cause any serious situation. This pest can occur 3 to 5 times a year, and they can overwinter. In March of the following year, they become active and begin to harm plants. Most of them gather on the leaves of plants, and they specifically choose new and tender leaves to suck the sap of the plants to survive. The color of the leaves will also change from the original light green or dark green to gray-green. Finally, the sap is sucked dry and the entire leaf will turn yellow. In addition to making the leaves extremely greasy, their secretions can also cause other plant diseases, such as sooty mold.

Solution

If you find it, you can spray it with a special pesticide first, and then wipe the leaves with a clean cotton cloth dipped in detergent water. Be sure to be gentle with your movements, but you can wipe it a few more times. Finally, wipe it again with clean water to prevent the residual detergent water from damaging the leaves. If the situation is serious, you can cut off the branches and leaves and burn them. When winter comes, the plants should be pruned and all diseased branches should be removed.