Conifers will continue to lose moisture through their needles throughout the winter due to osmosis to the surrounding air. This water loss cannot be replaced due to the frozen soil. Water loss is exacerbated by wind, warm winter days, or reflective radiation from nearby surfaces. Damage is not often evident until the spring, and will present as browning of needles with live buds.
Establishing a fall watering program to boost tree moisture levels is important. Establish mulch in the drip zone if lacking. Cambistat can be used for chronic issues to harden the petiole of the needle and reduce evaporative water loss. Root growth stimulants will increase water absorption in the root zone.
Apply every 3 years. $10/inch trunk diameter