Background Information
Bryophytes' most important role in the forest is to retain moisture. They can hold at least twice as much water as their weight. In fact, their whole life revolves around moisture. Bryophytes grow on tree trunks and catch the water falling down through the canopy. When the water reaches the soil there are bryophytes there to absorb it. In addition to retaining moisture, bryophytes also hold the soil together.
Bryophytes have two parts to them, one is haploid, and one is diploid. The green fluffy part of the moss is the gametophyte which is haploid. The part of the moss with a stalk and urn shaped hat is the sporophyte which is diploid. There are two kinds of growth forms for Bryophytes that will be discussed.
There are a few reproductive structures to know when talking about bryophytes.
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Kindbergia (or Eurhynchium)-
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Kindbergia oregana could be the state moss because it is so prevalent on the forest floor. This moss is a pleurocarp with a
fern-like appearance, and with its leaves bent away from the stem. Kindbergia praelonga is another species commonly encountered in the forest. It is smaller than K. oregana. The leaves are not as regularly branched from the stem as in K. oregana. The capsule is cylindrical. This genus grows on the ground, on logs, over stumps, and on the base of trees. These two species are considered large mosses. Isothecium is a pleurocarp with variable growth forms which makes it hard to identify. Normal shoots will look elongate and threadlike. The leaves are toothed on the more robust branches. At the place of attachment to the stem, the leaves will look as if they are clasping the stem. This species grows on rocks, rotten logs, and tree trunks. Isothecium stoloniferum ( also called Isothecium myosuroides)is one of the more common species found in PNW forests. Isothecium cristatum is an additional species one might encounter, but this bryophyte has a different appearance when it dries compared to I. stoloniferum. The capsule is upright and cylindrical.
Polytrichum is very charismatic because it resembles little trees. This bryophyte is an acrocarp with needle like leaves. Polytrichum juniperinum has reddish tips on its leaves called awns. It likes to grow on disturbed soil or can be found on a rock. Other species of this bryophyte will have a whitish awn or no awn at all. Species such as: Polytrichum commune, Polytrichum strictum ,or Polytrichum piliferum can be found in the Willamette National Forest. Most of these species can be very tall for mosses (up to 15 centimeters). In addition, both female (left photo) and male plants (right photo) can be found in the forest. The capsule will be upright and have 4 ridges.
Dendroalsia abietina will be the species observed in the Willamette National Forest. Dendroalsia abietina has two different appearances based on whether it is wet or not. The branches are arranged symmetrically on either side of the common axis. This is one of the larger bryophytes. When the bryophyte is wet, it resembles plumes of feathers. When dry, the individual shoots curl up into a fiddlehead. Capsules are nearly embedded in the underside of the shoot. This bryophyte grows in clumps on tree trucks and rocks.
Plagiomnium is a genus with many species such as: Plagiomnium venustum,, Plagiomnium medium, and Plagiomnium insigne. The two former species will have contorted leaves when dry. This genus can look like other genera such as Rhizomnium and Roellia so be cautious when identifying this genus. The shoots of this bryophyte can get up to 4 centimeters tall. There will be brown root-like appendages at the base and the leaf margins will have teeth. The capsules are droopy and smooth. Plagiomnium can be found growing on trees, rotten logs, soil or rocks.
Hylocomium splendens is a beautiful bryophyte with stair-step morphology. Each step is a year's growth which means this bryophyte can be dated. Hylocomium is considered one of the large bryophytes with stems getting up to 4 centimeters long. Each shoot is branched multiple times giving it a heavy feather-like appearance. Hylocomium grows in mats on logs, rocks, or humus soil. The capsules are oblong and at an upward slant.
Homalothecium is a yellow-green pleurocarp with straight leaves. Species commonly found in Willamette National Forest are Homalothecium fulgescens (left) and Homalothecium nuttallii (right). This genus could be misidentified as Brachythecium when wet, but when dry it has glossy distinctly upcurled branches. Homalothecium has pointed leaf tips and may, or may not, have teeth at the leaf bases. Homalothecium grows on logs, tree bases, tree trunks, and rock. The capsules are upright.
Neckera is a genus that is quite common in PNW forests on conifer and hardwood trees. The shoots look flattened with small and large branches, depending on the species. Neckera is a pleurocarp with brownish green, pale green, or pale yellow-green shoots. This genus can form large hanging mats on tree trunks. It is also found on rock occasionally. Neckera menziesii and Neckera douglasii are the two most common species in the Willamette National Forest. This genus has small to immersed capsules.This genus could be mistaken for Antitrichia. Macroscopically, Antitrichia has fluffy, bushy shoots, whereas Neckera has flat shoots. Capsules are cylindrical, and within the shoots.
Niphotrichum elongatum used to be named Racomitrium canescens and some books use the second name. This species is a yellowish, greenish acrocarp with tufted shoots when wet (right photo).
Niphotrichum grows in think carpets on the ground. The leaves have white tips called awns. When dry the species shrivels up and the awns are bent (left photo). Niphotrichum elongatum can be found growing on soil, rock, gravel, and sand. I have found this species in abundance along forest roads. Capsules are upright and pointed when young. Leucolepis menziesii (also called Leucolepis acanthoneura) is one of the large, dendroid, or umbrella bryophytes in the WIllamette National Forest. The leaves have teeth on the margins and the reddish brown stems have white scales. The shoots can get up to 7 centimeters tall. The capsules are smooth and droopy. Leucolepis menziesii grows on logs, soil, and boulders, and sometimes on tree bases.
Rhytidiadelphus is a large bryophyte which covers the forest floor and tree bases. This bryphyte is a glossy green color with a reddish stem. The species found in the forest are: Rhytidiadelphus squarrosus, Rhytidiadelphus triquetrus, and Rhytidiadelphus loreus. Rhytidiadelphus squarrosus is different from the other species by its large downward curving leaves that clasp the stem at the base..Rhytidiadelphus triquetrus is distinguishable by its shaggy shoots and triangular leaves. This genus can be found on logs, soil, humus, and grassy areas. The capsules are horizontal and oval shaped.
Porella is a liverwort, not a moss. It is a large leafy liverwort to be more exact. The leaves are entire or toothed and they overlap like shingles on a roof going up the stem. This genus of liverwort has two kinds of leaves, underleaves and regular leaves. The underleaves are very small and hard to see. The liverwort grows on trees in moist habitats. There are actually a few species found in Oregon but we will focus on Porella navicularis. Porella navicularis has entire leaves and underleaves that can be seen rather easily. The capsules are different from those of mosses and are rarely noticed without a hand lens.
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