Question
One particular oak tree in the backyard has a thick web spanning half of the circumference, yet all the way up to the top of the tree.  What is it, and how do we get rid of the Web?  I can attach an image soon...  Thanks

Answer
You can send a picture to [email protected] with a  subject line of "Allexpert question pictures" and I will
try to ID the problem.

Good pictures.

The webs on the trunk is bark lice.

Bark Lice are more properly called Psocids (pronounced "SOSS-sids"). They are also called tree cattle because of their habit of living as a group on the bark of hardwoods, particularly oaks, and have been reported locally on citrus trees.  Large numbers of adults and nymphs are occasionally observed on tree trunks often living underneath the fine silken webbing they construct.  These insects do not attack the tree, but feed on lichens, fungi, and dead animal and plant matter.

Peer carefully under the thin webbing that is found on tree bark, and look for the one-quarter inch long adult Psocids, which are brownish-black in color. Their wings will be brown with some white markings, and appear like a roof over their body.  The younger nymphs will be smaller and look like the adults except that they are wingless. Eggs are small and are whitish in color.

Usually, the first noticeable sign of the presence of this insect is the fine silken webbing. The bark lice secrete this as a protective covering on the bark.  This silken webbing has a silvery sheen and may cover parts of the tree trunk and large limbs.  When the webbing is pulled off, it is not uncommon to see hundreds of these insects.  This webbing is not found on the twigs or leaves, and looks different than webbing produced by destructive caterpillars.

The adult female psocids lay their eggs in clusters or piles on leaves, branches, and the trunks of trees.  Upon hatching, the nymphs begin to feed on dead animal and plant matter, lichens and fungi.  They are usually gregarious, which means the adults and nymphs will remain together under the silken webbing.  When the webbing is removed, they usually all move away in a group - they  are commonly called tree cattle because of this herding habit.

Webbing barklice are found throughout Florida, and along the Gulf coast from Texas and along the Atlantic coast north to South Carolina.  They are distant relatives of the booklice, which are household pests that can consume wood and paper products.  These outside Bark lice are not a threat to either the inside environment or to Florida Yards.   Populations of these tree cattle rise and fall with the seasons - cooler weather kills off many in the winter, and as springtime temperatures rise, food sources increase, and more webbing appears.  The greatest populations are found in the fall before the onset of cooler weather.

Managing your Tree Cattle
No control measures are recommended for these insects.  If the property owner objects to the webbing of these insects, a strong blast of water from a hose will dislodge them from the tree.  But as scavengers, they perform a valuable function in consuming excess accumulations of lichens, dead bark, and other materials found on the outside of the tree.  On trees that are regularly sprayed with insecticides for other pests, psocids will rarely be seen.  If the homeowner does insist on removing these insects, a Pest Control Operator may be contracted to apply a legal insecticide. If left alone they will soon disappear.