We focus too much on tree growth. Thus, because of the hierarchy, when we focus on growth, the tree's defense against pests is diminished. If trees grow fast, they can not defend themselves so they die young. An example is Cottonwood. If trees grow slowly, such as the Oak, they live a long time.
Trees are like people - live fast, die young.
John Ball is an Assistant Professor of Arboriculture at South Dakota State University at Brookings.