Specimen 8: Polytrichum commune

Figure 1: P. commune loosely grouped together. 

Figure 2: Four sided capsule of P. commune with green spores inside.

Figure 3: Acrocarpus gametophyte with very tall sporophyte (Magnification x8.4)

Figure 4: Long lance shaped leaves with costa and small teeth. (Magnification x24)

Name: Polytrichum commune
Phylum: Bryophyta
Family: Polytrichaceae
Common Name: Common Haircap Moss
Collection Date: September 10, 2015
Habitat: Bog area, on ground.
Location: Triangle Lake Bog State Nature Preserve, Ravenna, Ohio
Description: Tall, acrocarpus moss about 6 cm tall. Individual branches squished together tightly like a mat. Leaves lance like.  Tall sporophyte (about 4 cm tall). Leaves are about 6 cm long.
Collector: Linden Glaze

Key used: McKnight, Karl B. et al. 2013. Common Mosses of the Northeast and Appalachians. Princeton University Texts, New Jersey

Keying steps:
Key Features Path to the Keys (pg. 16):
Key Feature 1: Growth Form.... Acrocarp
Key Feature 2: Leaf Shape.... lance-like leaves, acrocarp
Key Structure 3: Midrib..... lance-like arcocarp with midrib... Key II pg. 342

Key II: Acrocarps with lance like leaves (pg. 342)
1. Plants yellow green, with shoots loosely associated, midrib present..... 3
3. Not submerged in water, found on soil,,,, 4
4. Leaf surface not wavy when wet.... 9
9. Leaves mostly greater than 4 mm..... 10
10. Wet leaves thick, stiff and opaque when held to the light when wet, resembles pine needles, midrib difficult to see... 14
14. Leaf margin toothed expect along the base...... 17
17. Capsules 4 sided like a box..... 19
19. Capsules with a disk at attachment to stalk..... Polytrichum commune (pg 57)