The difference between them is the Pure Sine Wave inverter produces a better and cleaner current. They are also considerably more expensive. You might find it practical to get a small Pure Sine Wave inverter for any special need you may have, and also a larger Modified Sine Wave inverter for the rest of your applications.
Elm Trees can live over 100 years in their natural environment.
Elm Leaf Beetle image licensed under CC. The female beetle lays eggs on the leaves of elm trees. The larvae and the adult beetles eat the leaves. The larvae crawl down the tree and hide when it is time to change to adult beetles. In some areas of the country, there are two or three generations during the summer.