Anyway, back to flocking!
Stick a couple of the trees into a scrap piece of styrofoam and spray your glue down from the top of the tree only in order to cover only the top half of the branches.
Quickly move over to your pile of flocking and sprinkle some down from the top covering the branches.
Turn the trees over upside down and gently tap the bottom to shake off any excess flocking on to the clean newspaper.
Repeat in any necessary spots. But again irregularity makes it look natural. After the glue has dried spay them with a clear matte lacquer for protection.
Here is another tip: cheap unscented hair spray is almost all clear matte lacquer. Just in different packaging. The cheaper it is the more lacquer it contains.