Pests of Dogwood

Cornus officinalis and fruit borers (Cornus cornus borer, Cornus officinalis)

Fruit moths mainly feed on fruit flesh, and the pest rate is relatively high. The damage is more serious during the fruit ripening period.

Generally, when fruit borers appear, you can spray 5000~8000 times diluted 2.5% cypermethrin or 2000~4000 times diluted 20% cypermethrin for prevention and control. Alternatively, you can disinfect the soil or use vinegar and dichlorodiphenyltrichloroethane to make poison bait to kill adult moths.

The second is to process the fruit promptly after harvesting and not store it for too long to reduce the spread of pests.

Cornus officinalis and the great moth (debt-avoiding moth)

The larvae of the giant moth feed on the leaves. In severe cases, they can eat all the leaves of the Cornus officinalis tree. This will weaken its growth and reduce the number of fruits.

Generally, when large moths appear on Cornus officinalis, they can be killed manually. After the leaves fall in winter, they can be combined with pruning and picking off the sacs hanging on the branches. You can also install black lights to lure and kill adult moths. Spraying is mainly used for prevention and control during the pest outbreak period, spraying 2000~3000 times diluted 10% pyrethroid or 1000 times diluted 40% oxydemeton-methyl. Biological control can also be carried out.

Cornus officinalis and the wood looper (bridge-building insect)

The larvae of the wood looper feed on the leaves, causing the branches to become bare, weakening the tree's growth and producing fewer fruits.

July is the peak period for larvae, so it is necessary to spray 1000 times diluted 90% dichlorodiphenyltrichloroethane for prevention and control. In early spring, you can dig up the soil to kill the pupae or disinfect the soil to prevent the pupae from emerging.

Dogwood and Leafhoppers

The adult leafhoppers suck young branches and leaves, which can seriously cause branches to dry up and leaves to fall, affecting the growth of trees.

The prevention and control method is to spray 2000 times diluted 50% phosphamide emulsion or 5000-8000 times diluted pyrethroid drugs.

Cornus officinalis and thorn moth

The larvae of the spiny moth feed on the leaf flesh, affecting the vigor of the tree, causing flowers and fruits to fall, and reducing yield.

If the ears of Cornus officinalis appear, you can use lights to lure and kill them, or eliminate the overwintering cocoons. Chemical control can also be used, such as spraying 5000-8000 times diluted cypermethrin or 1000 times diluted 80% DDT.

Dogwood and Scale Insects

The most common scale insects are the Paramecium scale and the Oyster scale. The nymphs suck sap, affecting the growth of trees.

Generally, when scale insects attack Cornus officinalis, you can introduce natural enemies or carry out manual control, or use 1000 times diluted 40% omethoate emulsifiable concentrate, spraying once every 7 to 10 days, for a total of 3 times.