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Season 22, Episode 10

  • Aired: 02/17/2011
  • 29:15
  • Rating: TV-G
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.
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Season 22, Episode 10
Season 22, Episode 10
Crayfish Invasion; Lichen; Heritage Trees; Working Dogs for Conservation
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