A reader from Xingguo County, Jiangxi Province, wrote in to Wang Peilan: I have grown over 100 potted crab claws, and I’ve noticed many white spots on the flattened leafy stems. The scion part of the plant has almost completely died, and even the rootstock (cactus or triangular arrow) has also withered. Is this a pest or a disease? How can I prevent it? Answer: Based on the samples you sent by mail, it appears to be an insect infestation rather than a disease. The main cause is damage from scale insects. You can see both white shields and waxy coverings on the plants. Scale insects are particularly difficult to control because they have a thick waxy layer that protects them from most insecticides. This makes them a persistent and hard-to-eradicate pest. To prevent further infestations, consider the following steps: First, when purchasing plants like crab claws or fairy fingers, make sure to thoroughly inspect the scions and rootstocks (such as cacti or triangular arrows) for any signs of scale insects. If you find any, remove them immediately to prevent the infestation from spreading to other plants. Second, avoid placing your cactus or related plants near infected ones. Keep them separate to reduce the chance of scale insects moving from one plant to another. Third, ensure good air circulation and proper lighting. Healthy growing conditions help plants resist pests more effectively and reduce the likelihood of infestation. Fourth, if you spot a small number of scale insects, use a soft brush to gently remove them. You can also scrape them off with a bamboo stick or rinse them away with clean water. For live insects, using transparent tape can be an effective way to lift them off. If the infestation is severe, you can spray the plants with a solution of 50% malathion EC diluted at 1000 times, or 25% DBP WP at 2000 times, or 40% emulsifiable concentrate at 1000 times. Make sure to spray both sides of the plant evenly for best results. These methods have proven very effective in controlling scale insects. North Pacific Squid Ring,Seafood Squid Ring Frozen,Frozen Food Squid Ring Zhoushan Xifeng aquatic co lid. , https://www.xifengaquatic.com
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