The woolly alder aphid, scientific name Paraprociphilus tessellatus, refers to a small insect species belonging to the family Aphididae that infests and feeds on the sap of alder trees, primarily the black alder (Alnus glutinosa). The term "woolly" comes from the aphid's fluffy and white waxy appearance that covers its body, granting the insect a distinctive appearance.
Adult woolly alder aphids are quite small, measuring around 1-2 millimeters in length. They exhibit a typical aphid body structure, characterized by soft bodies with six legs and two short antennae. They have piercing-sucking mouthparts that are used to extract nutrients from the alder tree's phloem vessels.
These aphids typically reproduce asexually through a process known as parthenogenesis, allowing females to give birth to live nymphs without the need for fertilized eggs or mating. This reproductive strategy enables rapid population growth and colonization of host plants.
Infestations of woolly alder aphids can lead to notable damage to their host trees. The aphids weaken the alder's growth by diverting vital nutrients and using the excess sap for their own sustenance. Additionally, their feeding activity often triggers the secretion of honeydew, a sticky substance that can further harm the plants and attract other pests, such as ants or wasps.
The control of woolly alder aphids typically involves natural predators such as ladybugs, lacewing larvae, or parasitic wasps, as well as insecticidal soaps or horticultural oils.
