Jeff
Red roots for junipers are perfectly normal. Nearly all woody plants will have darker roots as the roots age, but there are exceptions here too: Buxus species have white roots even when massive. Some species even have black roots (Diospyros or persimmon, Corokia). Nearly all healthy roots will have a very thin outer skin which when scraped lightly with your fingernail will reveal white or lighter wood underneath. Healthy roots will have clearly bright and vibrant color under this skin. Dead roots will be brown underneath and look like wet dead wood.
For many species, only the growing tips are white, and the length of the white tip varies by species, nutrition and even the time of the year. Most people don't examine roots nearly enough. Nurseryman make it a regular practice to tip a can over and gently knock out the rootball to examine the roots. When you make a habit of doing this, you will gain a lot of experience of what to look for in a healthy rootball.
Brent
EvergreenGardenworks.com
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