Bryophytes and Lichens: Small but Indispensable Forest Dwellers . What is a Bryophyte? What is a Lichen? Bryophytes are the small Lichens are dual organisms green plants commonly consisting of a fungus and an known as mosses, liverworts alga or a cyanobacterium. and hornworts. Compared to The fungus provides the alga plants, they have primitive with structure, protection, nutrients, and water absorbed . tissues for conducting food foliose lichen. and water, and they lack a yellow specklebelly. from the atmosphere and the protective outer surface to Pseudocyphellaria crocata. substrate (e.g., soil, rotten maintain water balance. Somelogs, examples tree branches). of In Most bryophytes, because return, the alga provideslichens carbohydrates are, the fromscientific photosynthesis they lack tissues such as to the fungus. Algae from some lichens grow independently liverwort. name follows the common roots, obtain their water of the fungus, but in lichen form, the algae can inhabit conehead liverwort. more challenging environmentsname: than when growing alone. through Somedirect surfaceexamples contact of Conocephalum conicum. withbryophytes their environment. are, the scientific Most lichens can reproduce asexually. They either produce Duringname dry follows weather the they common have the capacity to withstand specialized propagules containing both partners, or parts of the lichen simply break, allowing both the fungus and the completename: dehydration. Bryophytes that are dry may appear dead but will regain normal function when moisture is alga to disperse together. In some lichens, the fungal available. Instead of producing partner reproduces sexually by releasing spores, but the seeds, bryophytes can either partner alga must be present in order for a lichen to reform. reproduce sexually by means of spores, or asexually when small Lichens are grouped into three categories of shape: pieces break off and grow into foliose (leaf-like), fruticose (shrub-like), and crustose (growing closely attached to a surface). new individuals.

fruticose lichens.

hornwort. dotted hornwort . Anthoceros punctatus. Devil’s matchstick. clustered coral. Pilophorus acicularis. Sphaerophorus globosus. mosses. crustose lichens.

juniper haircap moss. Polytrichum juniperum. bullseye lichen. Douglas‘ neckera. Placopsis gelida. Neckera douglasii . map lichen. Rhizocarpon geographicum. U.S. Department of the Interior USGS FS-154-02 U.S. Geological Survey December 2002 Cryptogams. transport from the roots, plants Bryophytes and lichens, begin to close the small pores collectively referred to as in their leaves that allow non-vascular cryptogams, gas exchange. This con- are important components of serves water at the expense forests and other ecosystems of reduced photosynthesis. around the world. They are In the humid conditions especially conspicuous in created by cryptogams, forests of the Pacific North- plant leaves lose less water west. Despite their small so they can keep their pores size, cryptogams are open longer and continue abundant, and by draping photosynthesizing. tree branches and trunks and Nutrient Cycling. carpeting the forest floor, Lichens play an especially logs, and rocks, they provide important role in forest . much of the unique aesthetic nutrient cycling. Low soil appeal of Pacific Northwest nitrogen is typically a forests. Their combined limiting factor for plant biomass on some rainforest growth in Pacific North- trees may exceed the biomass west forests. Lichens with of leaves or needles on those cyanobacterial partners, trees. A close look at a single such as seaside kidney branch or tree trunk provides ( ) only a hint of the enormous Nephroma laevigatum and lettuce lung ( diversity of these organisms. Lobaria ), are able to ‘fix’ Washington’s Olympic oregana . nitrogen. This means they Peninsula alone is home to more than 1000 species. can convert nitrogen gas Bryophytes: Lichens: directly from the air to a Without cryptogams, the forest The various habitat niches Liverworts Foliose would lose much of its visual of a big leaf maple, from the usable form, something that Hornworts Fruticose beauty and many essential ground through the canopy, vascular plants cannot do. Mosses Crustose contain a diversity of Many lichens grow on tree ecological functions that cryptogams. These resident cryptogams provide. cryptogams, in turn, benefit the maple branches, but may be knocked by fixing nitrogen, and moderating to the ground during storms. Hydrology. loss of water and nutrients. Some common species are: Left side from top When these lichens decom- Bryophytes absorb water to bottom — Graphis scripta, Frullania pose, the nitrogen leaches into like sponges. Moisture nisquallensis, Antitrichia curtipendula, the soil and becomes readily Anthoceros punctatus. from fog and rain is Right side from top to bottom — available for other plants. collected by cryptogams Ramalina farinacea, Porella navicularis, Lichens and bryophytes growing on branches in courtesy of Erik Ackerson Rhytidiadelphus loreus, Peltigera britannica. concentrate various nutrients the canopy, tree trunks, deposited from the atmosphere, and the ground. Consequently, . Δ Seaside kidney which in turn become available cryptogams slow the rate at fixes nitrogen. to other plants when they are which water is lost from the When the outer layers are eaten by leached by rainfall. Many forest ecosystem. In addition, animals, a bright organisms depend on lichens yellow interior is . they reduce erosion, a process Δ for food. This is another way revealed. that can that can wash away seaside kidney in which nutrients assimilated soil nutrients, damage the Nephroma laevigatum by lichens cycle in the forest. forest floor, and adversely Rodents eat ground-dwelling affect the integrity of streams. lichens, whereas elk and deer are Microclimate. especially fond of nitrogen-rich Water stored in bryophytes and lichens lichens such as lettuce lung. A evaporates slowly, and helps to maintain bright yellow color on seaside . a humid environment in forests long after kidney is an obvious sign of rainfall has ceased. This is important not consumption by animals; the outer only for the growth of cryptogams, but rich layer has been eaten, which also for plants. As evaporation of water exposes the less succulent and from leaves exceeds rates of water courtesy of Erik Ackerson less nutritious yellow interior. Intriguing Facts About Bryophytes and Lichens. Δ

Δ It has been esti- Native mated that lettuce Americans lung provides an made the average of 3.2 poisonous kilograms of nitrogen horsehair each year for each lichen edible hectare of Pacific by steaming lettuce lung Lobaria oregana Northwest forest. courtesy of Erik Ackerson it in a pit . oven for two . days.

Δ Some horsehair lichen Bryoria fremontii bryophytes, common witch‘s hair such as Alectoria sarmentosa and Bryoria sp. Sphagnum Lichens, such . moss, can Δ as common witch’s hold up to . hair, frequently Δ The age in seven times obtain moisture years of stair- their weight from fog, helping it step moss can in water. . thrive near the be determined . by counting . .. timberline on Mt.

Sphagnum sp. Hood in Oregon. the number of Δ stair-step moss “steps.” Seemingly lifeless lichens and Hylocomium splendens bryophytes become photosynthetically active within minutes after wetting. ochre disk crust Ochrolechia laevigata courtesy of Erik Ackerson

A variety of bryophytes and roof screw moss Δ Tortula ruralis lichens are able to grow on a surface (substrate) as inhospitable as rock. . . Δ The work of a botanist! Δ Exploring the realms of Alder bark is naturally red-brown cryptogams often entails a but appears white because it is covered by lichens, such as the ochre disk crust.

very close examination of courtesy of Erik Ackerson the subject matter.

Many invertebrate animals, such as some insects, make their homes in mats of bryophytes and lichens. Invertebrates hiding amongst these cryptogams are a food source for various birds that may also take advantage of the natural Many species such as the marbled murrelet (left), rufous hummingbird

nesting sites afforded by cryptogams or use Hamer courtesy of Tom (above), and winter wren (right) use them as a source of materials for nest building. mosses for nesting material.

Shelter. Special Species Discovered on the Olympic Peninsula. Δ Goblin gold – . Some rare bryophyte and lichen species have been found Some of the largest recently in and near Olympic National Park, northwestern and healthiest known Washington. populations of this rare moss are on the Δ Flag moss – Olympic Peninsula. This moss has been found only goblin gold three locations in Washington. Schistostega pinnata .

Δ Bent-kneed four-tooth – This rare moss is found in association with decayed logs and other . large woody debris.

flag moss Discelium nudum . old-growth specklebelly Δ Old-growth specklebelly – bent-kneed four-tooth Pseudocyphellaria rainierensis A Pacific Northwest endemic, Tetraphis geniculata this lichen occurs only in very old forests. Over twenty .

new locations have been discovered on the Olympic Δ Common scissorleaf – Peninsula, some with large, healthy populations. A rare liverwort found in forested coastal bogs. Δ Northern fan coral – This lichen was not previously known . from the lower 48 states, but is now found in the Olympic National Park. common scissorleaf northern fan coral Herbertus aduncus Bunodophoron melanocarpum .

. Conservation. Many impoverished Bryophytes and lichens lack bryophyte and lichen many structural barriers communities in the cat-tail moss common to plants that limit eastern United States are Isothecium myosuoides entry of water, gases, nutrients recovering thanks to cleaner air in the last few decades. and harmful substances. Many The greatest risks to the vast biodiversity repre- species are sensitive to air sented by moss and lichen communities are poor air pollution and have been used as quality and loss of critical habitats. These issues are common witch‘s hair biological indicators of change. mainly societal, and the fate of these special organisms Alectoria sarmentosa Sensitive species exposed to is a factor to consider as people make individual pollutants have a stunted, aberrant appearance, and slowed decisions that shape our world. growth rates. Common witch’s hair is a sensitive species commonly found in Pacific Northwest forests. Contacts Martin Hutten (email: [email protected]). Photography, except as noted, by Martin Hutten. Andrea Woodward, USGS Forest and Rangeland Ecosystem Science Center, 600 East Park Ave., Produced in partnership Port Angeles, WA 98362 (ph: 206-526-6282 ext. 332; with the National Park Service. email: [email protected])