Answer: Based on your description I just can't tell if your plants are over or underwatered or have done a bit of normal fall shedding -- and unfortunately based on a description I can't tell if the color change you are describing now is a normal response to cooler temperatures or a sign of a problem. There are many types of arborvitae on the market and "Pyramidal" is used as a descriptive term rather than indicating a specific variety. For this reason I can't tell you if yours is one of the types that normally browns in winter or not -- some do. The ultimate size is also an unknown for the same reason. I'm really sorry I just can't be more helpful. You might want to discuss the plants with the nursery where you purchased them and possibly also with your local County Extension (285-4630) to see if they can give you a more specific identification of the problem (if any) and suggested remedies.
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