DES MOINES, Iowa  — Summers will be a steamier in neighborhoods across the country as crews cut down millions of trees in an effort to stay ahead of a small, shiny bug.

In cities like Waterloo, Iowa, workers are in the midst of taking out 4,000 ash trees that tower over homes and shade city streets. The same is happening in big cities and small towns from Pennsylvania to Colorado as officials respond to the emerald ash borer, an insect native to Asia that is killing ash trees in at least 22 states.

Amid the roar of chain saws, there may be hope for some ash trees. New treatments are available.

Cities like Milwaukee and Chicago are treating thousands of trees with insecticides rather than removing them.