Oregon Field Guide

Crayfish Invasion; Lichen; Heritage Trees; Conservation Dogs

Season 22 Episode 2210 | 29m 15s  | Video has closed captioning.

Crayfish Invasion - Eastern crayfish invade Oregon rivers through a surprise route. Lichen - Lichen can teaches us volumes about the quality of the air we breathe. Heritage Trees - Portland's Heritage Tree program recognizes and preserves trees with special significance. Working Dogs for Conservation - A conservation dog uses his amazing sense of smell to help a researcher find rare plants.