Question
My 3 year old Hawthorne tree has leafed out but the bark below the canopy looks dry and is peeling off. It is a smooth brown color underneath. I see white "fluff" and ants under some of the loose bark. The tree is about 9 feet tall. I live in Denver, Colorado.  Is this normal or should I do something to protect the tree from any damage that has or will occur.  Thank you.

Answer
Sounds like aphids. The bark as the tree grows will become rougher and some what peel. The aphids are small soft bodies insects that feed on plant juices of the leaves and sometimes under the bark scales. The ants are coming to and feeding on the sticky substance (honeydew)secreted by the aphids. The ants will actually tend the aphids so they will make the substance that is high in sugar content. The fluff is a waxy material produced by some of the aphids species. Generally called cottony aphids. Some of these type insects are called bark lice also.


Check with your local nursery/garden type store for an insecticide for aphids. This is a common problem on plants and are easily treated with an insecticide.