The yellow spots merge and turn brown. If SSM damage is allowed to continue, the general color of the tree foliage can turn yellow and rusty orange. Mite-damaged needles are more likely to drop off in the fall or after the tree is harvested. Pest description . The SSM in Fraser fir is a small, red to almost black-colored mite.
Young mites are smaller than the adults and have six legs.
When immatures molt, they may appear to be dead as they go into a resting stage before they shed their old skin. Adults are larger and have eight legs. The eggs are small and round with a single hair coming up through the center. All life stages are present through the growing season. The SSM overwinters as an egg though during warm periods in the winter, live mites can be active.