swelling of scarlet ok twigs

[capecodtree]

I have several clients with scarlet oaks that are in decline. twigs in the canopy are swollen along their length,fairly uniformly. I suspect a wasp and am leaning towards systemic control. I pruned out the deadwood last fall and most of the swollen twigs. the tree has not leafed out well this spring and the client is very concerned. any ideas? there are other mature scarlet oaks on the property and in the area with the same symptoms. thanks, jim

 

[Raintree]

Do they look like horned oak galls?

View attachment 240892

 

[capecodtree]

scarlet oak

no, its a fairly uniform swelling along the length of the twig 2-6" long, 1/2 to 3/4" in diameter.

 

[Raintree]

The Callirhytis wasp can cause elongated galls on oak twigs.

View attachment 240912