DACF Home → Bureaus & Programs → Maine Forest Service →Forest Health & Monitoring → Invasive Threats to Maine's Forests and Tree → Hemlock Woolly Adelgid →Hemlock ID
Quick Key to Identifying Hemlock
Hemlock Description (Forest Trees of Maine)
More Needle Characteristics
Needles have 2 white "racing stripes" on the underside. Fir needles have similar stripes.
Bark Characteristics
Narrow, rounded ridges, covered in thick scales
Cinnamon red to gray in color
Crown Silouette
Conical to egg-shaped (more or less); fine branches give this tree a lacier appearance than spruce, fir or pine. The topmost branch often points away from the prevailing wind.
*OTHER LOOKALIKES: Douglas fir, a widely planted tree, also has single needles, flat in cross-section, attached on a stem but the twig is smooth (does not have raised bump). Douglas fir needles are arranged in a spiral around the twig (making it appear bushy) while hemlock needles are arranged mostly in a single plane (making the twig appear flatter). Yew, a widely used landscape tree/shrub, has single needles that look very similar to hemlock. However, it lacks the white lines apparent on the undersides of hemlock and fir. (Back to Key)