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Cetraria merrillii

PNW Range:
  West sideCommon
  East sideCommon
  Immediate coastNone
  Alpine or subalpineOccasional
Habitat: Well-lit branches in forests and on more open, exposed trees, such as Pinus albicaulis on rocky ridges; also in treetops of moist low-elevation forests; present at all forested elevations.
Substrate: Bark and wood, mainly on twigs of conifers (especially Pinus contorta, Larix, and Pinus albicaulis); also on shrubs, especially manzanita.
Synonymy: Kaernefeltia merrillii, Tuckermannopsis merrillii
Cetraria merrillii - Habit
by B. McCune
Cetraria merrillii - Apothecia
by B. McCune
Cetraria merrillii - Branches
by B. McCune
Scale: Bar=1mm unless noted
Growth Form
Fruticose: Never
Foliose: Almost always
Crustose: Never
Appressed Foliose: Rarely
Fluffy Foliose or Strappy: Almost always
Dangling Hair: Never
Erect Hair: Never
Appressed Hair: Never
Stalks With Squamules: Never
Stalks: Never
Squamules: Never
Single Holdfast: Never
Dangling Nets: Never
Lobe Width (mm): 0.6 (± 0.3)

Upper Surface
Upper Surface Color    (Dry) 
   Dark Green: Sometimes
   Black: Rarely
   Olive Black: Commonly
   Olive Brown: Sometimes
   Olive Green: Sometimes
Upper Surface Tomentose: Never
Upper Surface Pruinose or Scabrid: Never
Upper Surface with Network of Ridges: Sometimes
Upper Surface with Pseudocyphellae: Never
   Upper Surface with Holes into Cavity: Never
Cilia on Margins: Never
Lower Surface (Foliose)
Lower Surface Color    (Dry) 
   Olive Black: Almost always
   Olive Brown: Sometimes
   Olive Green: Sometimes
Veined Below: Never
Rhizinate Below: Sometimes
   Rhizines Squarrose: Never
Tomentose Below: Never
Cyphellae: Never
Pseudocyphellae Below: Never
Papillae Below: Never

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

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

Sexual Reproduction
Perithecia: Never
Apothecia: Rarely
   Mazaedium: Never
Disk Color    (Dry) 
   Disk Black: Almost always

Asexual Reproduction
Isidia: Never
Soredia: Never
Lobules: Rarely