Rare lichens in park among many varieties in area

Sean C. Morgan

Of The New Era

Hobart Nature Preserve is the home to at least three rare plant species, including Methuselah’s beard lichen.

Lichens are unusual in general, but Methuselah’s beard is even more so, hanging from tree branches like a fragile light-green, almost white, thread.

The lichen (usnea longissima) is locally fairly common but generally rare east of the Cascades, said Alice Smith, a botanist with the U.S. Forest Service Sweet Home Ranger District. It generally occurs in riparian areas below an elevation of 2,000 feet, growing in single strands unlike any of its closest relatives.

All lichen species in genus usnea produce usnic acid, which is an antibiotic, Smith said. Sweet Home Ranger District has had a number of people harvest other members of the genus for the acid, primarily for transport to Germany.

“We are like lichen heaven,” Smith said. “This is the place to be if you like lichen, the west side of the mountains.”

Lichens include a huge number of species, more than 1,000 in the Northwest, Smith said, and they share a number of features that make them rather unusual in the plant kingdom.

First off, they are not just plants. They combine characteristics of three different kingdoms into a single organism.

They share qualities of fungi, and some even share characteristics with bacteria.

One group of lichens acts like cyanobacteria, which fixes atmospheric nitrogen directly into the lichen, encouraging it to grow.

Their plant qualities are most similar to algae.

From the fungus side, it receives its physical structure, Smith said, while “the algae lets it photosynthesize.”

During this time of year, lichens are dull, almost lifeless dried husks of stems and leaves hanging loosely among tree branches.

Get one wet, and it can turn a bright green quickly, she said, dipping a chunk of lichen into a bowl of water to demonstrate.

Lichens are biologically active while wet, she said, with small mounds of spore becoming visible.

During the summer, they are dormant. During the winter rain, they grow.

“Little pieces break apart in the winter storms,” Smith said. Also spreading with a heavy spore, those small fragments latch onto branches and rocks and start growing.

They spread slowly because of the way they reproduce, and it “takes them a long time to colonize a stand,” she said.

Lichens will grow almost anywhere, as long as it has the environment it needs to survive. That means they are often found in dead trees.

That leads to a common misconception, Smith said, that lichens are bad for trees. People see a dead tree full of lichen and assume the lichen killed the tree.

Smith has fielded calls from people who say lichens are killing their tree, Smith said. It’s not the lichen hurting the tree. It’s something else.

The bottom line is they grow on almost anything, she said. Some will even grow on abandoned cars. They take nothing from the tree. They take their nutrients directly from the air, so they have no need to be rooted in dirt.

They also grow directly on the surfaces of rocks, usually in a circular rosette pattern.

As long as the media is still enough, they’ll grow on it, Smith said. Trees provide a place where they can easily access the nutrients they need from the air and rainwater.

About the most danger they present to trees is when they are wet. As they absorb water, they get heavier and could conceivably break a branch.

Some lichens, such as the lungwort, generally grow in forests more than 100 years old, Smith said. Bone lichens tend to do well in young stands. They are identified by being white on top and black on the underside while growing tiny tube-like leaves or fronds.

Lichens have a variety of uses beyond medicinal. They also serve as air quality meters.

One way to study air pollution is to sample lichens in a particular area for toxins, Smith said. Absorbing their nutrients from the air, they absorb toxins easily. In heavily polluted areas, the toxins will kill them, although some varieties are hardy and will take over in heavily polluted areas.

“Within a mile of Brownsville, the trees are orange,” Smith said. They are covered in lichens that have absorbed sulfur from a nearby mill.

Ideally, “you want to live in an area with leafy” lichens, she said.

Another lichen gets its name from its use, Smith said. The wolf lichen has been used in the past to poison wolves. The lichen is common at high altitude on the east side of the mountains. The lichen, containing vulpinic acid, would be wrapped in meat and left for the wolves.

Dried wolf lichen also is used ornamentally, often used for its bright yellow color for making wreaths.

Frutocose lichens, which resemble hairballs in tree branches, are often edible for animals, Smith said. “I’ve seen elk eat from them and pull them right off the trees.”

Douglas squirrels and birds use the lichens to build nests, she said, and Native Americans used the black tree lichen, also called the edible horse hair lichen, in a variety of recipes.

The Tsimshian, Blackfoot and Salish peoples would bury layers of the lichen with leaves in earth pits and steam it, eating it with onions, fish eggs or berries. Other tribes used it as a fiber for clothing or shoes. The Salish people mixed it with grease and rubbed it on the navel of newborn babies, presumably to prevent infection, while the Nez Perce tribe used it to treat indigestion and diarrhea.

A myth of the Okanagan placed the origin of the lichen with the Coyote, when his hair braid became tangled in a tree, he cut it loose and said his valuable hair should not be wasted.

“After this, you shall be gathered by the people,” he said. “The old women will make you into food.”