Which aphid is known for affecting walnuts?

The walnut aphid is specifically associated with walnuts and is known for its detrimental effects on walnut trees. This aphid feeds on the sap of the leaves and shoots, which can lead to reduced photosynthesis, stunted growth, and in severe cases, tree decline. The walnut aphid is particularly noteworthy because it can cause significant economic damage to walnut crops, making it critical for growers to monitor and manage its populations effectively.

In contrast, the dusky-veined aphid primarily affects other plant species, the greenhouse whitefly is more commonly known for impacting a variety of crops, mainly greenhouse plants, and the bandwinged whitefly is also not a primary pest of walnut trees. Each of these other pests targets different plants or crops, which distinguishes the walnut aphid as the primary concern for walnut growers.