Detailed Explanation of Pest and Disease Control Methods for Rhododendron scabrum

1. Pest: Red Spider Mite

Pest introduction: The female adult of this pest has a body length of about 0.3 mm, is dark red in color, somewhat oval in shape, with a raised back and 4 pairs of legs, dark red. The male adult is wedge-shaped, flat, and bright red. Multiple generations can occur each year. The adults overwinter in the roots of the plant and mainly cause damage on the underside of leaves near the midrib close to the petiole. From June to July each year, during periods of high temperature and little rain, as well as during droughts, they reproduce relatively quickly, and their numbers are also relatively high at this time. When the damage is severe, the affected leaves become rather withered and then fall off.

Control methods: Generally, when carrying out control, we can use manual control. After April, we should check frequently. If red spider mites are found on individual leaves, they should be removed promptly and burned. Alternatively, chemical sprays can also be applied.

2. Pest: Lace Bug

Pest introduction: This pest is also called the stink bug. It is a major pest of Rhododendron scabrum. Adults or nymphs gather together and parasitize the underside of the plant's leaves, sucking its sap and causing damage, resulting in relatively many pale white small spots on the leaves. At the same time, many dark brown insect droppings and shed skins can also be seen on the underside of the leaves. This will seriously affect its growth, cause its leaves to fall early, and also affect its flowering.

Control methods: Generally, at the beginning of winter, clear away fallen leaves and some weeds near the flowering plants, then bury or burn them to eliminate some overwintering adults. Chemical control can generally be carried out. In addition, it should be placed in a relatively cool location, which can reduce the appearance of the insects.