The mite was introduced into North America from Europe in the early 1900s and is now established in most fruit-growing areas. Males are smaller, lighter in color, and have pointed abdomens. Overwintering eggs are round, bright red, and have a small stalk, approximately the length of the diameter of the egg, arising from the top. Summer eggs are pale and translucent. Overwintering eggs are laid in groups on roughened bark, in crevices and cracks, and around bud scales on twigs and branches.
Eggs begin to hatch at prepink bud stages and continue throughout bloom.
Young mites move to newly opened leaves where they feed, mature, and reproduce. The rate at which mites develop is primarily temperature dependent. Hot, dry weather favors development, while cool, wet weather delays mite activities. Each female is capable of laying 35 eggs during her average life span of 18 days. Eight to 10 generations occur during the year.