Hemlock woolly adelgid is described as which of the following?

• A. White cottony tufts on bark, twigs, and foliage; multiplies rapidly.
• B. Cone-shaped galls on terminal twigs.
• C. Piles of pitch at buds.
• D. Defoliates Douglas firs in moist conditions.

Answer: (A)

White cottony masses on the bark, twigs, and sometimes foliage are the hallmark sign of Hemlock woolly adelgid. These fluffy tufts are produced by the insects as they lay eggs and feed on the tree’s sap, and populations can grow quickly in suitable conditions. Seeing these cottony masses is a clear clue that hemlocks are infested and at risk, especially since the insects reproduce rapidly and can cause tree decline over time.

The other descriptions don’t fit this pest: cone-shaped galls on terminal twigs point to different gall-forming organisms, piles of pitch at buds indicate resin flow from other injuries or pests, and defoliation of Douglas firs in moist conditions describes a separate defoliator affecting a different species.