Mountains intrigue me and I feel fortunate to have always lived around them. I’m fascinated not only by their beauty, their influence on global and local weather patterns, their geologic makeup and topography but also by the tremendous forces created by our dynamic planet that result in their formation: the upthrust and tilting over fault lines, volcanic bulges and breakthroughs, and of tectonic plates crashing and grinding into one another. I am also fascinated by the processes that wear them down. With the exception of volcanic action and the build up of lava, the forces of weathering away are easier for us to witness.
The following is an educational fiction story of how the process of soil building initiated on mountain slopes, over time, helps to change the face of a mountain in the northern latitudes at altitudes of 6,000 to 8,000 feet.
Chapter 1: Melt Waters
The last star of morning faded from the purple skies as ever so slowly the sun broke over the eastern horizon tinting snowcapped mountains a delicate pink. As the sun rose higher, the cold alpine air gave way to warming spring rays that cut through the chill and began soaking into the debris, dust and silt particles strewn atop the snow. Microscopic flotsam: pine needles, bits of moss, tiny seeds and dust had blown in on the winds and now collected warming solar rays that melted surrounding snow crystals. Drop by drop the melting waters carved veins into the packed snow layer atop the mountain’s rocky surfaces.
The thaw eventually reached into the higher snowpacks and remnants of ancient ice fields clinging to the granite hillsides. Trickles of melt water seeped into the glaciers’ crevasses, washed over their craggy brows and dislodged rock-strewn chunks that gathered momentum and cascaded down the mountainside causing an avalanche of snow, ice, silt and debris, twisting and tearing up all in its path until slamming to rest against the landscape below. Little by little the slowly moving glaciers slipping along on thin layers of melting water carved away the mountain: eating, digesting pulverizing all in its path; its fine silt or rock dust settling into the other trickles and waters that fed into creeks, streams and rivers flowing down the mountain.
Other hydrologic forces helped to break apart even more of the mineral rich rock across the alpine terrain. Moisture from the melt waters, the atmosphere and rains squeezed into fissures within the rocks, turned to ice at night, expanded and chipped away at the stone. It is not unusual on a warming spring day, to hear rocks clattering together and/or careening down the talus slopes as the expansion process breaks them apart and gravity continues the momentum of dragging them downhill.
Chapter 2: Lichens
On the dimpled surfaces of the rocks, crusty and leafy tan, greenish, gray and/or occasionally orange lichens soaked up the moisture like thirsty sponges. In a symbiotic partnership with green algae, the lichen housed and secured footing while the algae found protection from drought. Some lichens form a weak acid which eats into the rock. Slender fungal strands grow into the stone’s face and pass minerals to the algae which through photosynthesis and absorption of moisture produces food for itself and the lichen layer. Thus lichens helped to corrode and decompose the rocks setting the stage for other vegetation. Over the centuries, by-products from the life cycles of these primordial fungal and algal relationships mixed with rock dust to form primitive soils. Moss spores borne on the high altitude winds found nourishment and moisture within the shelter of the leathery lichens and gravely soils. They grew and formed emerald green mats which helped to speed up the soil building process, adding humus in which alpine plant seeds sprouted.
As the springtime temperatures warmed, blustery breezes played over the mountainside evaporating more of its moisture. The gusts blew about an outcropping of gravel and sand near the remains of a fire-blackened stump where a mottled and barred, brown and white-colored ptarmigan was dusting in a shallow depression. The bird scratched and scooped the grains of sand and grit over its feathery body. It stood and shook the dust from its hide, dislodging a molting feather. It shook again and took stiff-legged steps about the outcropping in search of bite-sized bits of grit to aid its gizzard in grinding down the food it ate. The wind tousled its feathers, then blew stronger, forcing the ptarmigan to seek cover. Before flying to shelter, the bird squatted and expelled a pile of coarse poop, then blurted off towards a clump of low willows and alders in a nearby gully. Walking among the sturdy branches it nibbled off the greening buds while waiting for the coming storm it sensed about to happen.
Like many mountain storms, clouds swept across the sky and piled up on the mountain peaks shrouding them in heavy mists. The ptarmigan continued foraging until forced to seek protection from a heavy downpour. It sheltered at the base of the willows while all around the rain released rich, earthy smells. The heavier drops of rain splattered the outcropping where the poop sat. Much of its softer parts disintegrated, washing into the sandy soils. The remaining weed seeds might swell with the potential to sprout and follow the power of gravity downward in search of nourishment.
Farther down the mountainside, fed by the glacier and melt water drainage, a forest seep housed a number of rodents and birds. Also growing were stunted aspen, alder and willows. Over the years, their leaves, aided by a host of soil organisms, had helped in forming the topsoil in which grasses, herbs, alpine flowers and low growing shrubbery and stunted trees took root. Mice feeding on the berries, grass roots, and tender barks found a safe haven to raise their families. Deer, elk and an occasional bear might also find temporary shelter within the seep’s environment affecting it by browsing, rooting about, passing urine and defecating rich scat.
Chapter 3: Summer Storms
As the spring’s rainy season climaxed, the fragile environments scattered across the mountainside prepared for summer’s heat. Mosses and lichens dried out and once again became leathery patches and tinder-dry lumps upon the rock faces. Grasses hastened through their growth cycle.The waxy coatings on the evergreen needles helped slow moisture loss and preserved a tree’s life but the leaves browned and turned crisp on deciduous trees and shrubs.
Summer rainstorms could turn potentially disastrous conditions into lifesaving ones by replacing precious moisture. At other times, storms could turn violent. The blackened stump near where the ptarmigan dusted was a remnant of such destruction. During the storm that resulted in the fire-scorched stump, lightning had slashed the skies with enormously powerful bolts of intense heat.Thunder rumbled loudly throughout the valleys. A tall double-tipped fir took a direct hit and burst into flame. The explosion sent showers of sparks into neighboring trees making living torches of their resin-filled branches. Glowing sparks fell onto the forest floor where dried grass and other debris kindled the fire and allowed it to spread widely across the mountainside in all directions .
Strong winds formed in the fire sending tongues of flame racing upwards. Plants lost their moisture, shriveled and were consumed. Insect bodies burst like popcorn and vaporized in the heat. Animals caught in the maelstrom fled or huddled in terror, their bodies singed of fur and feather. Thick smoke choked the forest and ashes swirled about the flames staying aloft in the fiery drafts. Elsewhere, fires followed the pitchy roots of fir and pine deep into the earth.
As the storm system passed over, it also brought rain but the blazing conflagration was too intense to be affected. Eventually another storm carrying with it more moisture arrived. At first, its water droplets vaporized before hitting the blaze but the rain fell heavier and cooled the flames allowing drops to fall lower and affect the fire itself. Steam rose from the blackened stumps and rivers of ash trickled down charred tree trunks. The smell of charcoal was overpowering.
The black-skinned earth continued belching smoke throughout the remainder of the summer. Hot spots deep in the roots of the pines and spruce persisted in smoldering until the drenching fall rains and heavy snows of winter snuffed them out.
Chapter 4: Spring Renewal
And when the gentle renewing winds of yet another spring blew across the mountainside, seeds and fungi spores were carried into the blackened forest. Aided by warm rains and the moon’s pull, the honeycombed heads of morel mushrooms pushed through the ash-covered earth. Grit and ash covered their ridges and pits. As the fungus matured, flies laid eggs that hatched into maggots. These grubs digested the mushrooms’ mass. The rotting caps and stems sunk to the ground and aided in the renewal of the soil.
Soil building was slower on the more exposed, rocky sites. Blistered by the intense heat of the fire, all life save the most microscopic would have to wait for winds to deposit soil, birds to drop seeds, lichens to etch the rocks and for the rains and snows to leave moisture through many seasons
By summer, grasses and annuals had begun to sprout where the fire had been less intense. Tall spikes of fireweed eventually marched across the burned areas. Their magenta-colored flowers attracted wild bees that hauled the rich nectar to safely hidden hives.
Standing snags, their bark partially burned away, became sentinel posts from which hawks watched for unguarded movements of smaller creatures. Over time a variety of crusty, leafy, branched, powdery and filamentous lichens and mosses grew on the snags’ sheltered sides giving them even in death, another living experience. Raspberry bushes sprang up among the charred remains of other trees toppled by the fire. The bushes offered safe havens for mice and other small creatures scurrying about searching for the fallen fruits and seeds.
The rain following the fire and subsequent downpours eroded sections of the fragile, steeper hillsides on which little vegetation remained to slow the process. Rivulets of ash and mud formed during spring runoff until plants grew and developed their root structures into the rich veins that locked together the soil. Through time, the deltas of soil and ash grew thick with grasses, then alders, aspen and birch which set the stage for heartier cedar, pine and spruce trees.
Potentially, over time, streams meandered along fern-lined beds and silent deer drank from their clear waters. Overhead, owls sought shelter in the cool shadows and squirrels gathered cones. Several species of grouse found nourishment in the abundant bud life, rabbits sought shelter among the thickets and bobcats and cougar staked out hunting territories. Little, if any but a few silent, remains of standing snags covered with lichens and drilled with woodpecker holes, remained as evidence of the flames that once seared the mountainside.
And so it continues. Through eons of dust, centuries of spring rains, summer storms and fires and winters of rest, the cycle of building soil helps sustain the life of a mountain.