Woolly Pine Adelgids – Pineus spp.

Woolly Pine Adelgids -Pineus spp.

Common Name: Woolly Pine Adelgids

Latin Name: Pineus spp.


The bug overwinters as an immature on the tree. As the temperature warms, they exude waxy substances like fuzzy tufts all over their body. Little clusters of eggs are deposited in the clumps in the early spring. Crawlers emerge from the tree and travel to different regions of the tree, or they are blown or carried to new hosts.

Host plant:            

Eastern white pine, Sometimes on Austrian and Scotch pine are common host plant.

Damages caused by Woolly Pine Adelgids:

This adelgid feeds on pine and spruce bark. They have a woolly appearance and may be mistaken for furry aphid species.

Adelgids of pine bark develop fuzzy or cottony white masses on the trunk, branches, or twigs. Under the white cloth, the adelgids are black and short-legged. On the trunks of trees, heavy infestations might resemble snow. Adelgids are found at the base of needles, on shoots rather than on trunks of seedlings and young trees. Hands frequently become yellowish (chlorotic). Severe adelgid infestations can cause tree stunting or mortality.

Life history and habits:

The Pineus pini life cycle is anholocyclic in Western Europe. Throughout the year, colonies can be found on the smaller stems and shoots of pine, with three or more generations each year. Pineus pini survives the winter as young forms hatched in early October. Immature forms can be observed in November, and these continue in their second or third instar until the following spring when they mature into sistentes. In March, they begin to deposit their eggs. In the second half of April, the egg clutches attain their maximum size. Large clusters of eggs are deposited, resulting in significant discrepancies in hatching dates between the first and final eggs. In May, numerous clutches of Pineus pini eggs with sistens on pine were photographed.