Eastern Hemlock
Flat short needles with pale undersides, tiny hanging cones, and drooping twig tips identify Pennsylvania’s state tree.
Artwork inspired by Daniel Garber
Eastern hemlock creates a darker, cooler forest than many deciduous trees. Dense evergreen shade moderates stream temperature, while roots, woody debris, and long-lived trunks structure ravines used by fish, birds, and invertebrates. Needles attach by tiny stalks and appear two-ranked along slender twigs.
Hemlock woolly adelgid feeds at needle bases and can kill trees, leaving white cottony patches visible on twig undersides. Do not move infested branches or firewood. Report new infestations through local forestry guidance and look beyond the individual tree: losing hemlock can warm water and change an entire ravine community.
- Needles
- Flat with two pale underside bands
- Cones
- Small and hanging
- Pennsylvania link
- Official state tree
Quick guide
- Turn the twig
- Two white stomatal bands show beneath each needle.
- Check the cone scale
- Hemlock cones are much smaller than spruce or pine cones.
Recognize and observe
- Turn the twig
- Two white stomatal bands show beneath each needle.
- Check the cone scale
- Hemlock cones are much smaller than spruce or pine cones.
- Search for adelgid
- White woolly masses cluster at needle bases.
- Protect the watershed
- Clean gear and avoid moving suspect plant material.
Good to know
Eastern hemlock is not the poisonous herb called poison hemlock. One is a coniferous tree; the other is an unrelated flowering plant.
Notice these
- Flat with two pale underside bands
- Small and hanging
- Official state tree