QuestionI have a 4 year old weeping cherry tree that has been under attack by Japanese beetles. I have hand picked some of the bugs off but it got to be too many, so I decided to spray the tree. I used an organic product called Neem. Shortly after spraying in noticed that about 20% of the leaves turned yellow and are falling off. Is this a result of the bugs or the spray or possibly something else. Any recommendation is appreciated.
AnswerIt is more than likely the oil. If the weather there has been hot or if the product was applied when the temperature was hot as in later in a day then the oil tends to burn the leaves. If only 20% of the leaves are effected there is not a a real concern. Water the tree during times of dry weather and the tree should see no effects of the burning. Oils are best used in the early spring or early morning hours.
