Are our evergreens dying?
We purchased an acreage on which there are approx. 5 acres of evergreens and cedar. Alot of the evergreens have lost and are still losing their needles. Do they have a disease and if so, is there something we can do to stop this? Will the dead branches come back?
Evergreens in South Dakota have had a tough few years. Considering the size of your lot and the variety of species there could be any number of things wrong with your trees.
Most evergreens go through some autumn needle drop, where they shed their older needles (http://byf.unl.edu/web/byf/EverNeedleDrop, http://learningstore.uwex.edu/assets/pdfs/A2614.pdf). This is a normal process and this could be what is happening on some of your trees.
The biggest cause of evergreen decline has been the drought of 2012. Trees that did not get any supplemental water this time have been turning brown. I started getting calls in early spring and they've continued all summer and fall. This is also a common topic in Dr. John Ball's tree pest alerts (http://sdda.sd.gov/conservation-forestry/tree-pest-alerts/).
For trees that you think have a disease, it would be easier to diagnose them if you have some close up pictures of the symptoms (oozing bark, wounds on the tree, evidence of pests, etc.).
Branches that are all brown will not get new needles. The trees in your first and third pictures look like they've lost a lot of needles and it might be more than they can survive.