Weather Forecast


Wind and asphalt are tough on trees

Q: I landscaped my entire front yard using a beautiful Japanese maple as the focal point. Three days later, we had the high, cool winds that lasted for two days. However, I'm sure the temperature never dipped below 55 degrees. The side of the tree that caught the wind now has leaves that have dried and shriveled up, although all the branches seem healthy. What can I do to nurse this tree back into shape?

A: Just give the poor thing a good watering once or twice a week, but don't overdo it.

Q: I've had a wisteria for six years, but it is has never blossomed. I am going to move it to see if I can get it to bloom. It usually has stems about 12 feet long. I tried trimming it last year because I read somewhere that might help it to bloom, but it didn`t. Do you have any suggestions?

A: If you don't have to move wisteria, don't do it because it does not transplant well. To get it to bloom in its present location, back off on the nitrogen fertilization and try some indiscriminate root pruning. This usually shocks the plant into flower production.

Q: My twin-trunk river birch is old, but very healthy. It is planted less than 10 feet from my asphalt driveway that now has extensive root damage. I have two questions. When replacing the driveway, can I cut off the roots that are doing the damage? It didn't damage the foundation, but veered off to start a path under the driveway.

A: I consider this a rather unusual occurrence, but roots will follow the path of least resistance. There must have been some kind of micro-channel in the soil and under the drive that contributed to this happening. Knowing the root system of birches as I do, I would remove the damaging roots and place a copper screen along the edge of the drive where the roots penetrated. This will discourage the tree from doing it again.

Q: I just purchased some tulips, hyacinths and daffodils. They are in bloom in the pots, so I would like to plant them. What would happen if I were to plant them now? Would they bloom next year?

A: Plant them now using the pots and all. If you try removing them from the pots to plant, I'm afraid they will start wilting. After they are finished blooming and the foliage has died naturally, remove the plants from the pots and plant them where you want. They should bloom next year, unless you live inside the Arctic Circle!

Q: I decided to uproot a lilac tree and put it in a pot. I am wondering if transplanting it will affect the plant's health.

A: If this is a mature lilac you will be uprooting, you might be wiping out too much of the root system to keep the plant alive in the container. Feeder roots for mature plants are concentrated at or toward the growing tips. The larger, woody roots function mostly as support and transport of the water and nutrients these fine root hairs pick up and send to the growing regions of the plant. I would think twice about transplanting because you don't unintentionally want to kill the plant. If you want a potted lilac, buy one in a container from a local nursery.

To contact Ron Smith for answers to your questions, write to Ron Smith, NDSU Department of Plant Sciences, Dept. 7670, Box 6050, Fargo, ND 58108-6050 or e-mail