Byron U.

Evergreens and the issues you have asked about. 

1.) When you notice brown on the evergreen it does not necessarily mean it is failing.  Pines regrow their needles ever three years and they will die from the interior out when this occurs. 

2.) Yellow does not mean it needs more water. As a matter of fact when your Junipers and Arbor Vitae turn yellow you are supplying to much water.   They prefer a deep water 1 time every 14-21 days depending on the soil.  (once they have been established)

2.b) When they start to turn brown and 'twiggy' they are lacking in the water department. Water when your finger is dry after sticking it into the soil at a 90 degree angle.  For best result 4-6 inches of the top soil should be checked.

3) Soil density really affects the growth of evergreen shrubs. You should get the soil tested to see what the composition on it is.  Landscapers tend to just use the plants you want and the soil condition isn't accounted for. For instance areas close to the lake, have more clay in their soil which makes for slow drainage, where as north Orem in on a river bed and is extremely rocky. This creates excessive drainage.

4.) Whole sections of branches on evergreen trees will die back if you do not us the correct techniques to prune them. 

5.) My tree's grow so slowly is there a way to speed their growth up? Unfortunately no but there are ways to encourage growth in certain areas.