In urban areas salt is regularly used to maintain streets throughout winter. While it is beneficial in eating away ice and snow, it can be particularly damaging to trees. As vehicles drive by, salty slush and water is often sprayed onto trees the line the streets. The browning needles are a possible indication of salt damage. It is best to contact a certified arborist, such as Local Arborist, to properly diagnose your tree and implement a plan for prevention and restoration.