Ball moss can be controlled using three methods: picking, pruning or spraying. Each method alone may not provide adequate control. Using a combination of all three methods results in the most thorough treatment.
Picking involves physically pulling each plant off the tree. This method can be very effective, but is extremely tedious and labor intensive. It can also be quite dangerous without the use of a cherry picker. Please use caution and practice proper safety techniques if employing this method.
Pruning consists of cutting and removing the dead, interior limbs from the tree and/or lightly thinning the canopy. The majority of the ball moss is growing on the dead, interior limbs; therefore, by removing these limbs, you physically remove the majority of the ball moss. As mentioned above, ball moss prefers areas with low sunlight intensity. Light thinning of the canopy (if necessary) allows more sunlight to reach the interior of the tree, discouraging future infestation. When pruning oaks, make certain to paint all pruning cuts immediately to reduce the risk of oak wilt.
Spraying involves applying a chemical to the tree in a foliar spray. Kocide 101 provides adequate control. Do not exceed the recommended rates for this chemical. Higher concentrations of this chemical can actually damage the tree. The ball moss will shrivel up and die in 5 to 7 days, but will remain in the tree until the wind or rain knocks it out. For this reason, it is recommended to prune out the deadwood first. In doing so, you remove the majority of the ball moss from the tree and practice proper tree maintenance at the same time. Neither picking, pruning nor spraying will remove all of the ball moss from the tree, but these treatments can benefit the tree and certainly make you feel better.