Since you mentioned "brown needles" I am going to assume we are talking about a pine tree - please correct me if I am wrong. What type of pine is it? After your tree was transplanted, what care did you provide it with regards to water, fertilizer and mulching? I am just wondering if maybe it suffered from transplant shock? When was it transplanted?
Secondly, are all the needles on your pine tree brown? Are entire branches brown or just the tips? Is it only brown on the bottom branches? Is the new growth turning brown? When did the needles start browning? Needles will sometimes turn brown after a cold dry winter, in such a case it just needs ample water and general care.
There are many reasons for browning pine trees, such as root rot, fungus/blight (fungicide would be applied), and pests such as pine tip moths (insecticide would be applied), just to name a few. Many of these causes are discussed in the links below.
Winter can be harsh on the gardens, plants and trees.
Since we are just entering spring, allow your trees to wake up before judging if you have lost a tree.
Here are a few links that may be of help.
I think you are talking about 2 different trees. A newly planted tree will be the most vulnerable.