Swales are used to help water trees at the root. It is suggested that you should grow nitrogen fixing trees. These trees are said to bring nitrogen back into the soil through the help of bacteria from like beans do. For a quick blog about this go to “Beans – The Nitrogen Booster!!”
Below is a list of nitrogen fixing trees
- Black Locust
- Eastern Redbud – (Zones 4-9) Click here to see more information found in Fast-growing trees.com.
- Autumn Olive
- Kentucky Coffee Tree (Zones 3-8) Click here for more information found in Fast-Growing Trees.com
Arkansas is in zones 6-8 so Eastern Redbud and the Kentucky Coffee Tree would be good choices for the Ozarks. For more information go to “Introducing Nitrogen Fixing Trees: Solution to curing N2 deficiency” article from Permaculture News.Org