Psocid Barklice nymphs travel in large groups and look troublesome, but their diet of exterior plant material make them good tree cleaners.
The term 'lice' tends to make people uneasy, but these are not the blood-sucking lice normally associated with the human body. Apart from their small size, they have nothing in common with human lice. Psocid Barklice are chewing insects and they do a stand up job of eating fungus, lichen, algae, broken bark, and other plant debris off of tree trunks. They prefer damp areas where the humidity helps foster growth and degradation of their food. Their nymphs often congregate around an area of the tree with algae or lichens on it and remove that patch, then move on to another. Like most large groups of adolescents, they tend to cause apprehension in observing adults, but Psocid Barklice are harmless. They do not sting or bite people and they do not harm the tree they are gleaning from.
Look for them in forests and wooded areas. Conifers and deciduous trees are both likely to have them if trunks are laden with growth. Psocid Barklice are active from spring to autumn in colder states and provinces, and all year in warmer southern areas. Adults are winged and may be seen near nymphs.
Scientific Name: Cerastipsocus venosus
Size (Adult; Length): 3mm to 6mm (0.12in to 0.23in)
Note: An insect's reach is not limited by lines drawn on a map and therefore species may appear in areas, regions and/or states beyond those listed above as they are driven by environmental factors (such as climate change), available food supplies and mating patterns. Grayed-out selections indicate that the subject in question has not been reported in that particular territory. U.S. states and Canadian provinces / territories are clickable to their respective bug listings.