Question

pine   QUESTION: I have 3 pine tree but only one does this. Why is my pine tree cones on the ground brown and shreded bare and all the needles are brown on the ground?

ANSWER: The debris is the work of squirrels. Perched high in the tree, they are eating pine seeds from the pine cones and dropping the gnawed cones to the ground. The cones contain seeds between the "leaves" of the cone and the squirrels are gnawing the cone to get to the seed.

The brown needles dropping is normal for pines--the pines are evergreen meaning they have two sets of needles and as the newer green needles mature the pine will shed the older needles. This gets the tree ready for the new needles next spring. There should be green needles left on the branches if not the tree itself is dying.

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QUESTION: can anything be done to deter the squirrels

Answer
The problem usually is an over population of animals so a population reduction in my mind is needed. However I would ask
Category:  Wildlife Damage Control
Steven V. Matthews   
He is the expert in this area.

http://www.allexperts.com/el/Wildlife-Damage-Control/