QuestionQUESTION: the flowers fell about 1 week ago. I went to prune it and saw holes,brown patches on the lower branches. Also, I noticed that the bark was chipping off and the branches are very weak. I found something that looked like a nest on the top of the center trunk. I dug it open with the blade of my lopper; it was so hard. Inside as I dug in there was an insect that looked like a beetle, but it has no legs. It is reddish brown with some black circular rings that bring it to a sharp point on one end. The other end is wider and has a small indentation that holds some king of stinging gel. I know that because i felt it when I picked him up. I believe it is this insect that is destroying the bark and weakening the branches. Also, brown patch like insects are destroying the leaves. We had a very cold and snowy winter that lasted until the beginning of April, followed by weeks of rain and unseasonably cold weather. What can I do? I love this tree.
Thank you,
Elise
ANSWER: Sounds like a couple of different problems--A borer insect has infested the trunk and a leaf eating has infested the foliage. Spray the trunk with an insecticide called Merit or Onyx. These will kill the insect in the trunk and prevent others form attacking. The foliage sounds like Japanese beetle feeding. The foliage should be sprayed with an insecticide called Orthene. This will kill the beetles feeding on the foliage. There are many other insecticides that will control Japanese beetle if you can not find Orthene,
Many insecticides are labeled for Japanese beetle control on landscape plants. Examples include acephate (Orthene Turf, Tree & Ornamental Insecticide), carbaryl (Sevin and many other brand names), cyfluthrin (Bayer Advanced Garden Multi-Insect Killer Concentrate), lambda-cyhalothrin (Spectracide?Triazicide?Soil & Turf Insect Killer Concentrate), esfenvalerate (Ortho Bug-B-Gon Garden & Landscape Insect Killer Concentrate), and permethrin (Spectracide?Bug Stop Multi-Purpose Insect Control Concentrate and many other brands). Neem extracts (Bon-Neem) deter Japanese beetle feeding but may not be adequate against high populations.
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QUESTION: I planted a 12' River Birch in my front yard in the spring. Twice,now, a great many leaves turned yellow and dropped off. Also there were many small offshoot branches that were leafless and brittle, so I pruned them. The tree was planted by professionals. I live in eastern Massachusetts. We had two weeks of rain after the tree was planted. Then blistering heat. Then 2 more weeks of rain. During the times when it was not raining, I watered the tree every day using drip irrigation. Also, an environmental company that I use, deep fertilized the tree, and a day later the leaves turned yellow and fell off. But the second time it happened, it was after deep watering. Do you know what is happening?
Sincerely,
Elise
AnswerSounds like stress from the lack of water and the fertilizer. A couple of things could cause the leaf drop. A tree this large needs more water than a drip line can give it especially river birch (they need more water than other tree species). I would water the tree with 1 inch of water--place a pan under the tree and turn the sprinkler on and when the pan has 1 inch of water in it stop. Do this every third day unless it rains. This will increase the root growth and next year it will not need as much water. Also if you have not done so mulch around the tree with not more then 3 inches deep of organic mulch not piled up on the trunk. Mulch out to about 2-2 1/2 feet around the tree. This will help hold moisture around the roots.
The fertilizer burned the new roots and fertilizing is not recommended for the first year after planting then only a cup per inch of trunk diameter scattered around the tree.
