Question: A foul-smelling liquid is oozing out of the trunk of our oak tree and is attracting hornets and butterflies. Is this something we should be concerned about?

Answer: This is referred to as slime flux or wet wood. It is caused by a bacterial infection within the tree. As a result of this infection and the presence of sugars within the tree, fermentation takes place. Pressure builds up from the production of methane gas inside the tree. Therefore, it begins to ooze and bubble out of the tree as the pressure increases. Yeast bacteria often take over, and a beer-like smell is produced. There is no treatment that will stop this. In actuality, it is a mixed blessing. Slime flux raises the pH and creates an unfavorable environment for the growth of wood decaying fungi. That is a good thing. Trees that are stressed from injury and disease tend to be more subject to infection. Examine your tree closely for those conditions. Hose down the area with water to reduce the smell, and close that bar down if the insects get a little too rowdy.

Question: There are dead branches in my trees and limbs growing over the house. Do I need to wait until winter to have them removed?

Answer: Summertime is a great time to do this work. Dead limbs are easier for a tree service to see when the tree is in full leaf. Live limbs can also be removed without fear of harming the tree. With that said, poor pruning practices that include topping, improper pruning cuts, or the removal of over 25% of a tree's leaf surface is not recommended. Dryer summer soil conditions allow for less damage to your lawn too.

Question: Why are the leaves on my dogwoods trees curling up and turning white?

Answer: They are infected with a summer disease called powdery mildew. It is a fungus that loves warm summer nights and high humidity. As a result of this infection the leaves appear to be dusted with baby powder but will not wash off. Infected leaves curl, turn yellow, and drop off. However, the tree will not die despite it’s sickly appearance. Controlling this leaf disease requires the application of a fungicide every 7-10 days starting in early spring. That was months ago. It is too late now. Besides, it is time consuming and difficult for most homeowners to follow. My dogwoods are infected too if that is any consolation. I pick my battles and that is not one of them.

Question: The branch tips of my hydrangeas are covered in what looks like cotton. What is this?

Answer: It is a waxy substance produced by an insect called a leafhopper. There are many species of leafhoppers that feed on the sap of plants. You may dislodge a few by slowing taking your finger and running it through the wax. It is then you will learn how they earned their name. The best way to remove them is by using a garden hose to wash them off. A spraying of insecticidal soap or a homemade version will work too.

Rett Davis is a retired Alamance County Extension Director and Certified Arborist. You can email your questions to Rett_Davis@ncsu.edu.