the bug or worm is coming out at night time....this is an active nut tree....try making a mix of 1 teasp of liquid hand soap and water and spraying the tree...you will have to double or triple this....spray on and under the leaves and around the ground. if it is crawling up the tree...you could use 3 inch wide tape on so the sticky side goes around the tree and the sticky sides meat and cross 1 inch over do 3 more lines....the worms & bugs will get caught then you can see what this is. if this does not work....the you have to get sevin and check the directions to see if this tree is included on the list. wear long old clothes, hat, mask, goggles & gloves.........keep children & pets away from this until dry.....in the fall do dormant oil as this smothers any eggs in the bark that has been laid.