I live on Long Island, New York. I have 17 arborvites along one side of my property planted together. They are about 15 feet tall and were there when I bought the house 7 years ago. They have always been very healthy looking until the end of last winter when I noticed they were browning and dropping needles, apparently from the inside out. I have been told it's everything from shedding due to lack of water to pests. We did have another group of arborvites on the other side of my property that were browning when we first bought the house. At night, there were many small moths swarming the trees. These trees were removed. I see no moths on my current one's.

Now the odd part, only my side is browning, the side that faces my neighbors is still green and healty looking. My side faces North. Any ideas?? THANKS!! Would hate to lose these.