Diminutive Decoratorsby Mary Jasch
Got lichens? You're breathing clean air! "On an ash tree growing in the city you wouldn't have any of this. When you come here, the trees have a completely different energy." - Glenn We head for the Cedar Swamp Trail and spy a boulder with two kinds of rock tripe - brown rubbery smooth rock tripe and bumpy toadskin. Along the gravel road to the swamp, the hunters brake for a patch of mixed Cladonia species -- spiky little urchins with brown or red caps, some forked, some with powder horns strutting above their squamosa -- all worth crawling on your knees for. Soon, a pink lichen in the mold group! Tiny treasures! On a nearby tree, bright yellow crustose next to a silvery species laden with apothecia - tiny tart-like fertile structures that release fungal spores. Lichens on the roadway, lichens on soil that prevent wind erosion, on trees, rocks...everywhere. When lichens are in an environment where they grow vigorously, they'll grow on almost anything. They want moisture and bright light, and have preferences for substrate, such as pH, nutrient quality, and the nitrogen-rich bark of ash, walnut, apple. Some prefer conifer bark for its lower pH. One species grows on rocks underwater in fast-flowing, clear, streams at high elevations. The blue-grey color on Atlantic white cedar, Smullen says, is a Lapraria species consisting of powdery granules. Lichenologists debate whether Lapraria is only a juvenile stage that dies. But if so, how does it reproduce? And I thought it was just the color of cedar. A turkey-like peppered rock shield lichen covers a rock with moss. The sensitive-to-sulfur-dioxide hooded tube lichen hangs from Mountain Laurel. When it reproduces, its inflated lobes burst open like trumpet lips covered with powdered sugar. Tarts on a dying red maple wait to erupt. “As a tree dies it releases nutrients, so lichens grow vigorously on branches that are dieing," Glenn says. “They need light, so branches with no leaves or needles support more lichens. They grow with only the water of the dew. The algae becomes hydrated and photosynthesizes for two hours before the dew evaporates." On trees, lichens are epiphytes or they grow on each other. On rock, they dissolve minerals and create soil. They provide a nice base so that if a moss spore or seed falls on a lichen rather than bare rock, it's more likely to germinate and grow. “A lichen may end up dying as a result of a spore germinating and covering it up. On that micro scale, we can understand how succession takes place," says Glenn. Lichens aggregate soil particles. The hyphae penetrate soil, providing a netting that helps prevent erosion. They do this on a finer scale than plants do. Some lichens have root-like rhizines. Others are “soil crusts," forming a hyphael network on the soil surface. The relation of lichens to air quality is its most determining survival factor. They grow in high nitrogen areas including trees in horse pastures where they pick up volatile ammonia, under bird perches and around feeders. “Lichens are just out there," Glenn explains. “If you imagine trying to display sensors over an area the lichens are out there as air quality sensors. They are useful indicators of pollution. If the air is clean, as pollution develops, they drop out of less favorable habitats." “The ruby-throated hummingbird makes its nest of cinnamon fern hairs, spider webs, then the female picks off the lobes of Punctelia and Flavoparmelia and camouflages the nest. The lichens also repels water," says Smullen, New Jersey Mycological Association member. Lichens on boulders placed in the landscape are short-lived or grow very slowly, up to 1 millimeter a year. They grow best under a forest canopy. Plants, whether they're trees or grass, increase the moisture level through transpiration, as opposed to paved surfaces. But for those who insist on having moss and lichen-encrusted boulders in their gardens, Glenn gives this advice: 1. try to reproduce the original micro-climate or those lichens will not last long 2. re-orient the boulder the way it was in the wild. If the lichens were facing north, face them north in your yard. Was the boulder in the open or under trees? If you want lichens in your garden, place a rock where you can feed the birds who, in turn, will give it a little fertilizer. But if you want to see some real beauties, take a walk on a wooded trail, a little off the beaten path. Bring a hand lens and prepare to spend some time peeking at a colorful world in miniature. LICHENS OBSERVED ALONG THE KUSER NATURAL AREA and CEDAR SWAMP TRAIL, High Point State Park, 1/2/07 compiled by Dorothy Smullen Foliose on bark Flavoparmelia caperata common greenshield lichen Punctelia rudecta rough speckled shield lichen Punctelia subrudecta powdered speckled shield lichen Parmelia sulcata hammered shield lichen Pseudevernia consocians antler lichen Hypogymnia physodes hooded tube lichen (sensitive to S02 pollution) Physcia milligrana mealy rosette lichen Phaeophyscia sp. (white medulla) Parmeliopsis subambigua (collected as unknown - best id- pale underneath with brown short rhizines, pustular soredia clusters all over lobes) Foliose on rock Flavoparmelia baltimorensis rock greenshield lichen Xanthoparmelia conspersa peppered rock shield Umbilicaria mammulata smooth rock tripe Lasallia papulosa toadskin lichen (pustules on surface) Fruticose on soil Cladonia rei wand lichen (brown apothecia) Cladonia coniocraea powderhorn lichen Cladonia chlorophaea mealy pixie-cup Cladonia cristatella British soldiers Dibaeis baeomyces Pink earth lichen or pink mushroom lichen Crustose thallus and fruticose apothecial stalks Cladonia ciliata? Crustose on bark or rock Candelariella sp. ? Bacidia sp. ? Ochrolechia sp. ? |
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