We have a tree we planted about 2 years ago. During certain periods of the year, its leaves start to look burnt at the edges. I always thought it would be because of amount of rainfall or sunshine, until we started to remove the burnt, very damaged leaves and I happened to look at the underside of the leaves, and found a bunch of incredibly alien looking insects I had never seen before. It was here that, I believe I am correct, and hope...that I realized they are the reason the leaves start to die. I still do not know what they are, but there were just toooo many of them underneath the leaves it looked bit a gross, especially I noticed, the leaves that displayed the most damage. It may not look like much in the green photo, but there were dozens of them. The tree is Tacoma Stans. I did not find pests for it on the internet...so far For now, all I can think of to help the plant, is to dislodge them with water at a high pressure and see if they come back too quickly. I dont know if they have wings, I could not see any flying. It also looks as if they had a needle or something on their face. I took some not too great photos. Thanks!