Solutions for yellow, brown leaves to keep trees alive
Q: I planted a live oak tree two weeks ago. It was looking good until we had a rainstorm and now the leaves are turning brown. What do I do now?
A: Check to be sure the roots aren't standing in water. If so, dig spoke trenches to get the water to drain away from the roots. Check to be sure that it isn't planted too deeply. If it is, then pull the excess soil/mulch away from the tree until you reach the crown, which is the point where the trunk becomes the root system. If it is neither of these problems, then all I can suspect is a lateral movement of some herbicide into the root system that is killing the tree.
Q: I have had my jade indoors for about five years. A week ago, I moved it outside to a shady spot under a pine tree. We have had very hot and humid weather this week, but also some rain. The plant now has very red stems and the leaves at the tips are getting soft. Any suggestions?
A: I would say that you have nothing to worry about. The plant is responding to the change in environment. Keep in mind that the genetic hardwiring of this plant is in the tropical regions of South Africa, so it shouldn't buckle under any hot temperatures in North America. Just don't allow the plant to dry completely, but also don't overwater it. Remember that jade is a succulent.
Q: We have an arbor that we would like to grow grapes on, but my daughter only likes green grapes. Is there a variety of green grape that would be suited for this purpose and this region? Also, I would like to know about a raspberry bush I could grow in this area.
A: The only one I know of that has a chance of growing in Jamestown is the edelweiss because it was produced in Minnesota. A couple of good raspberries would be latham, which ripens in early summer, and Redwing, which is a fall-ripening variety.
Q: My grapevine is finally producing fruit, but now I have discovered that Japanese beetles love the leaves. My husband has sprayed with Sevin. However, I have found that a few of the leaves have little, furry growths on the backs of the leaves. This may be impossible for you to diagnose, but I am grasping for help. Our Extension Service people have moved from the area, so now I don't know who to show this problem to for assistance. Thank you for any help you may be able to give me.
A: This could be rust spores developing. See if you can locate a Bordeaux mixture on the local market to use to keep this fungus from spreading.
Q: I have a 5-year-old autumn blaze maple. It was a 12- to 14-foot tree I purchased from a nursery and came in a pot. The tree appears to be growing and healthy. However, the leaves are very yellowish green. Any ideas as to what is wrong?
A: If the tree has been in its present site for that long, then it is suffering from either iron chlorosis or nitrogen deficiency. You can try correcting it with applications of an iron-based fertilizer, such as one containing iron sulfate or any other iron-containing fertilizer available on the local market. The nitrogen needs of the tree should be met with normal lawn fertilization. Ignoring this will lead to the eventual premature death of the tree, so work on getting it corrected at your earliest convenience.
To contact Ron Smith, write to Ron Smith, NDSU Department of Plant Sciences, Dept. 7670, Box 6050, Fargo, ND 58108-6050 or e-mail firstname.lastname@example.org.