The 159 acre Hendrickson Canyon NRCA contains Wahkiakum County's last high quality, mature and old growth western hemlock forest, with trees 100 to 120 years old and scattered older trees.
The forest is significant because there are few remnant stands of mature or old growth forests remaining in the Willapa Hills and because it contains a high quality representation of the western hemlock/Oregon oxalis community type. (Wahkiakum County)