Birth Of Soil (1948)

[Music] this is topsoil to mankind topsoil means food and life it exists only upon a small savoured fraction of the Earth's surface and it averages the depth of only six inches your life depends upon the six vital inches it takes nature from ten to thirty human generations to produce a single inch of topsoil a single inch since the days of Columbus topsoil is not just a collection of minerals and chemicals it is alive it can be injured and it can die this desert in New Mexico was once good grazing lands but over blazing destroyed the protecting grass allowing wind and range of scatter the soil and destroy it forever roughly one quarter of the land in the United States is suitable for cropland we have learned about one-tenth of our original heritage and damaged more than one half of what remains some of it seriously we are losing each year by bad management and the resulting erosion the equivalent of nearly half a million acres which are rivers carried down to the sea what is this heritage we are losing and why is it so important where did it come from here are the materials nature uses to build topsoil air sunlight and rock with water as its lifeblood however Nietzsche faced organises these elements into a form that life sinew many agencies and forces bring about these changes and one of these is temperature at the foot of this cliffs this great mass of rock was broken apart by expansion and contraction due to changes in temperature here the same process has been carried a step further yet another process is the grinding of the rock here the clear green eyes of a glacier with its enormous weight moves down the mountainside the glacier acts like a giant file up on the rock already the ice shows streets from the particles of rock torn from the mountains at the foot of the glacier we find the ice covered with a blanket of raw ground from the mountains faced with the passing of time the glacier melts and then rock particles are released as we see here the broken rock is dropping from the face of the glacier splashing into the water of a glacial lake the rock particles are carried down hill by a stream formed by the melting ice water continues the grinding process and by the turbulent action of the current the particles of rock are reduced to ever find our side here the Glacial scream carries ground up rock into a clear Brook to be deposited later in the valley sand or gravel water plays another role it dissolved minerals from the rocks leaving the less soluble part to stand out the dissolved minerals become available for plant food now an entirely new set of forces goes to work here in HS pioneers the tiny lichen can gain a foothold even on the face of a barren Rock pass it from the lichen roots dissolved minerals from the rock these lichens absorb moisture from the air they grow reproduce and die there remains often mixing with dust and sand produce a seed bed in which higher forms of plants can grow these in turn die and contribute their substance to the seed bed until on a bare rocky ledge we find organic matter deep enough to support a small tree these simple plants have enacted the floor our eyes are most astounding gamma they have taken dating organic rock and air into their own living bodies and here is a miracle of life as this beam rises from its seed bed the cells in its stem respond to the light turning the leaves toward the Sun and now the heart of the miracle the chlorophyll the miraculous green coloring matter in the lead captures energy from the sun's rays the plant takes elements from the air and from the soil and build them with the help of this energy into its own living body the leaves follow the Sun through the day presenting their broadsides to its Ray's until it sinks in the West then the stems relax and the leaves group below the surface the roots reach into the soil and from it absorb but the dissolved materials which are carried up and eventually built into the plan ninety-five percent of the plant is made of elements originally contained in the air some of these come to the plant by way of the soil in the form of water and nitrogen compounds the other five percent originates in the soil itself and into this body of n eight elements the plant has locked the sun's energy the key and spark of life when the plant dies it lays on the Earth's surface this store of energy and the elements taken from the soil now moves bacteria and in take millions of them to the ager break up the plant mixing it into the earth and in this process of decay the dead plant becomes available as food for other plans mr. king substance also forms a spongy human we can absorb water without this humise the rain that sinks into the raw soil keeps right on thinking washing the valuable minerals out of the soil in a process called lychee but with this humise the soil acquires not only a new plant food but for the first time adequate power to absorb and store water with its life-giving minerals underground the worms do their part by eating the rock particles digesting them and casting them up of the surface several tons to the acre each year thus enriching the surface and replacing the minerals used up by the plants step by step the characters the soil has changed the dark topsoil has taken shape if we plant seeds in two boxes one of topsoil the other of subsoil here is what we find nearly double the growth in tops or a partial measure of the difference between the fertile soil our country started with and the man-made desert we are fast building for ourselves and so from an environment in which pioneer lichens were barely able to exist life serves up a richer environment where plants can find the energy to elaborate higher form to grow rich in burien each new form helping to prepare the way for the next this then is nature's gift to us living topsoil a link in the chain of life which began with nature's raw materials the sun's energy the chlorophyll in the plants living tops or that thin precious blanket averaging only six inches deep which we must conserve for nature will not give those inches a second time those vital int that mean the difference between death and life for mass [Music]