Under-watering

September 2012

I have a screen of seven mature arborvitae that are scorched on their south sides; the north sides are lush and green. I have used soaker hoses about once a month letting them run for a total of 8-9 hours moving the hoses every 2 to 3 hours to cover the entire root zone. The next day this is repeated on the north sides. They were faithfully sprayed for bag worms this spring and I see no infestation. On the south sides the needles are brown from the tops of the trees to the bottoms and from side to side and fall off when gently brushed. Some of the needle bearing twigs are still pliable but most are dry and brittle. Should I keep watering or are they unsaveable?

Once a month in a summer like we had was probably not enough to keep them healthy and thriving. If an evergreen goes brown from the tip of the branch to the trunk, it usually means that particular branch is dead. I would say you have a tree that is half dead and half living. Could something have been sprayed on the south side? Needle-type evergreens like arborvitae don’t rebound well. As I see it, you have three options. You can continue to enjoy the screening from the healthy north side of the plant, replant entirely, or plant something on the south side to mask the dead branches..

May 2012

We have four large (20 feet tall) Japanese maple trees in our front bed. They are 15-20 years old and have seemed very healthy. Last week, my across the street neighbor cut down one of his Japanese maple trees in his front yard because it had died. Seemed like it died fairly quickly, just a year or two and it was gone. He has another one also in his front yard that is has some dead major branches. Then, I took a closer look at my trees and discovered that they all have many dead branches, although they are small branches, no major ones. I am concerned that there may be some kind of disease. What should I do?

Japanese maples were hit hard by last summer’s extreme heat and drought. If they weren't watered, they may have died or had some major damage. My neighbor had a large old Japanese maple that is totally dead this year. Plants that were stressed would be more susceptible to insect and disease attacks. Check out the trees, looking for any holes or splits in the stems or leaf spots on the foliage. Remove any dead branches. A little thinning never hurt a Japanese maple. Water when dry and hope for the best. If you do see signs of insects or diseases, take a sample in to your local extension office.