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Usnea longissima

Overview
PNW Range:
  West sideOccasional
  East sideNone
  Immediate coastOccasional
  Alpine or subalpineNone
Habitat: In Oregon and Washington usually on riparian trees, both conifers and hardwoods, at low elevations, but seldom in broad open valleys; most abundant in a narrow band transitional between the mountains and foothills.
Substrate: Bark and wood.
Comments:
Synonymy: none
Usnea longissima - Branches
Branches
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Usnea longissima - Habit
Habit
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Usnea longissima - Branches
Branches
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Usnea longissima - Field appearance
Field appearance
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Usnea longissima - Branches
Branches
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Usnea longissima - Field appearance
Field appearance
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Scale: Bar=1mm unless noted
Growth Form
Fruticose: Almost always
Foliose: Never
Crustose: Never
Appressed Foliose: Never
Fluffy Foliose or Strappy: Never
Dangling Hair: Almost always
Erect Hair: Never
Appressed Hair: Never
Stalks With Squamules: Never
Stalks: Never
Squamules: Never
Single Holdfast: Rarely
Dangling Nets: Never

Upper Surface
Upper Surface Color    (Dry) 
   Pale Yellow Green: Almost always
   Pale Green: Almost always
Upper Surface Tomentose: Never
Upper Surface Pruinose or Scabrid: Never
Upper Surface with Network of Ridges: Never
Upper Surface with Pseudocyphellae: Never
   Upper Surface with Holes into Cavity: Never
Cilia on Margins: Never

Interior
Inside (Medulla) Yellow or Orange: Never
Central Cord: Almost always
Hollow Stalks or Hollow Lobes: Never
Gelatinous: Never

Photobiont
Green Algae Primary Photobiont: Almost always
Cyanobacteria Primary Photobiont: Never
Internal Cephalodia: Never
External Cephalodia: Never

Chemistry
Usnic Acid: Almost always
Cortex KC+ Yellow: Almost always
Medulla P+ Orange or Red: Rarely
Medulla K+ Orange or Red: Rarely
Sexual Reproduction
Perithecia: Never
Apothecia: Rarely
   Mazaedium: Never
Disk Color    (Dry) 
   Disk Pale Greenish: Almost always
   Disk Brown or Tan: Almost always

Asexual Reproduction
Isidia: Never
Soredia: Never
Lobules: Never

Usnea Specific
Papillae: Never
Branches Cigar Shaped: Never
Central Axis Pale Yellow: Never
Cortex Reddish in Part: Never
Central Axis Thick: Almost always
Main Branches Nearly Unbranched: Almost always
Branch Surface Wrinkled: Sometimes
Fibrils Abundant: Almost always