Answer: Wow! It's a lot of work to transplant that many trees! If these were bareroot transplants, then they may well have suffered shock during the transplanting process, especially if roots dried out at any stage of the process. If the weather is dry and windy, the trees may transpire (the process of drawing water from the soil and evaporating it from the leaves) more water than you have been supplying them, or they haven't yet produced enough new roots to take up the moisture they need. Trees do better with a slow-release nutrients, provided by mineral dusts (black rock phosphate, bone meal, greensand) and compost, than those provided with a water-soluble fertilizer.
I'm not sure if fall-transplanted trees will have enough time to grow adequate roots to support them through a high-country winter. My instinct is that spring transplants will fare better. Your best bet is to consult with the county forest service (you'll find them listed in the white pages under US Dept. of Agriculture) and learn the preferred practice in your region. They'll also be able to better advise you on how much moisture your trees need based on the soil type and transpiration rate. Best of luck with your new forest!
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