Dial environmental failed to diagnosis a fungus on one of my evergreens (20-year old), which ultimately resulted in the tree having to be cut down. What's worse, your arborist gave all of my trees a clean bill of health only one month earlier. The diagnosis was made my a delivery man from our local nursery who was delivering a tree earlier in the spring-- he noticed it immediately. When I notified DE, they were slow to respond. In terms of the mosquito control-- the service is spotty. One gentlemen does a great job, the others-- no so much. I have used DE for many years, but after my contract is completed, I will not use them again.