| Show t THE ROCK LICHEN A Remarkable Soil Maker OUR MOUNTAINS OF BY J H PAUL DIRECTOR OF NATURE STUDY IN THE STATE NORMAL The world Is a farm and the air all and water are the first but not the only plowmen Son Soil is natures product made ready for tor the operations of ot hu human human human man agriculture long before man touches It with plow or spade The ox oxygen oxygen gen of the th air all in the presence of mois moisture moisture moisture ture corrodes and eats away the metal metallic metallic lic veins and the ores of various kinds mingled with the solid rock which forms the crust or solid soUd part vart of the earth For the earth is isa a rock cov covered covered ered in most places with a thin ex extremely extremely thin layer of soil soli Its lower places also are covered with water the oceans The oceans and the other waters wear this rock into stones gravel sand and finer powder Dowder called clay lay and silt The carbon dioxide of the air attacks the rock especially the limerock and dissolves it in the rain rainor or water that contains the carbon dl di Plants attack the rock with their acid roots and both dissolve and rend them apart Microscopic organisms called spores the seeds of minute al algae algae algae gae and fungi germinate and grow to together together together gether on rock surfaces and dissolve and pulverize the hard rock into fine powder The rain enters the crevices of The rock dissolves out the rock ma material material ti Cerial and freezing In winter rends the rock apart till it is split off 0 in scale like pieces of all sizes Wind rain rivulet and river carry mix and spread out this soil material Beetles enrich it by burying bUring organic matter and the bodies of small ani animals animals animals mals beneath the surface Ants plow and work it up in m making their homes Angleworms pulverize it into fine pow powder powder powder der and mix it with the decaying leaves which they eat The burrowing ani animals mals gophers rabbits chipmunks squirrels badgers etc turn up the soil and transport it for short distances T V Every movement of tree roots of un unde de r Und or surface water every change of temperature heat frost etc contributes to the pulverizing and grinding up process Numberless mi microscopic microscopic plants called bacteria set to work upon the manure of animals and change it into forms in which the thela la larger ger plants can an use it Then nature covers the soil with vegetation that Springs up by reason of seeds trans transported transported transported ported to every corner of the earth Hain or dew irrigates the crop Bees and other flying fi insects the flowers so that the seeds will ill ripen Birds and toads keep leep dow down a the Insects that would otherwise destroy every crop i in n natures great garden And so soman soman s o oman man is able with the aid of these and other natural laborers to gather a crop from his small gardens gar gardens gardens dens while natures vast product is raised to 10 feed the unnumbered hosts of animals not used by man Problem of the Rocks Next time you ou go into one of our canyons pause before a large rock mass there and consider how it might be converted Into a soil surface fit to support a growth of vegetation You Tou might ask how this can be done Can man with wi h plows even een with steel plows sledge hammers crowbars etc convert this rock into soil soli He can cannot cannot cannot not but nature has ways of doing this vast ast and apparently impossible piece of or work ork This rock and in fact all rock certain natural agencies seem de determined determined to form fonn into soil It requires greater power Dower than man has at his hist command to transform these solid t barren rocks Into hi to plant food Man ran can neither JeIther plow pl w nor successfully sow saw seeds here herd They would only blow away a It is useless to try Seeds Already Sown Yet if we stop ston to to look at the rock with a microscope we shall find that it is not altogether barren for when we look closely we find that something has already alread been sown there The pioneer laborers before belore de described described described scribed have just begun the work It was far from finished when they left It It Seeds have been scattered here by b nature and are not to be wasted Float Ing about In the air are countless numbers of spore dust substances that correspond corre pond to the seeds t bf f other plants The minute spores and cells ceUs of these strange forms of vegetation that make up the lichen are carried upon every breeze and travel around the whole globe The resulting vegetation which can be seen on every old rock rockwall rockwall rockwall wall roof and tombstone and on the rock rack masses mn es of all our mountain tops furnishes one of the most Interesting and instructive chapters of nature study Photographic marks on rocks are usually lichens the hard coating of green yellow ellow gray and black mos mos a U as it is generally generall called ailed ad hering to rocks long exposed Is com composed composed composed posed of lichens The spores or fine dust from i which they grow are i o 0 light that they the cannot settle unless the air is very quiet and even then the least breeze will ill disturb them But they the are somewhat sticky and tills this quality enables them to remain when once they alight so that the they cling to bare rock A As soon as settled they the begin to grow They are the first tra traces e s of vegetable life lICe to put In an appearance upon UDon recent lecent streams of lava laU The lava laa lichens are just like helpless stains of dust and are art no noticeable noticeable only onh to those who look out for them Upon first acquaintance we not discover or even suppose that they would be at all dangerous to hard rock for they the look perfectly lifeless However they are art very ven much alive and are not at all like the ant which comes and goes when its work is done The lichen on the contrary comes to stay slay and It never leaves until It Is bodily displaced by more important members of the plant kingdom In Intact fact tact lichens are simply the advance guard of the vegetable host with which nature natura has planned to break down sooner or later the hard barren sur surface surface face of the rocky rock crust rust of the tho earth and to convert It into productive soil This is a process to be sure which requires years ears and decades for its completion com completion completion In the case of the lava rock it must first cool and great numbers number of the lichens have been scorched to death in their attempt to settle upon the masses They The have also at some time found the rock too glossy gloss and have failed to secure a lodgment lod ment thereon being blown blon away as fast tast as they the came But others con continue continue continuo to arrive until with help of or the pioneer laborers they the soon roughen the rock rook and are able to fix themselves with so firm a hold that neither wind windor 1101 or rain can dislodge them Then they t ey begin to grow x Food of the Lichens Do you you suppose that at least these plants contrary to the general rule must live on air all and water Not at atall atall atall all they are good feeders and consume con consume consume sume more mineral minerai matter than any an another other plant of their size The rock soon crumbles down enough to enable them to fasten themselves upon it and to top p send fend nd their threadlike arms into the tiniest crevices They are arc like the seaweed In one re ref f 4 r V V VV t r i P C Cs Cof s 1 Common species of Lichens A an erect branching form r rm lichen Shell C Os Bt B a spreading over the bark of tree for they the have no roots These are the organs as all know through which plants usually take up UD their food Unlike all other plants the li lichens lichens lichens chens do while the others do not feed directly upon rock Other plants would starve where the lichens thrive While some lichens are at first fiat only mere stains even these contrive to tomake tomake make mak a living JIving out of the rock wherever they can gain a footing Of course they do not take up the rock particles they dissolve the tho rock They are so strongly acid that they are able to dis dissolve dissolve solve and take up from the rock the main food they the need The color of these plants Is steely gray gra rusty rust brown bright yellow and orange They are harsh to the touch They remind one of minerals more than vegetables Sometimes over a fifth of their substance consists of solid goUd matter which they have literally eaten from the rock surface They Prepare Soil As the lichens grow gro and die year ear after year ear they prepare in time a soil suitable for mosses the second class of living soil makers These grow grO and die with the lichens To Together Together Together gether they the form with the dissolving and crumbling rock a deeper soil But the mosses absorb much moisture and where there Is moisture frost trost and the atmospheric gases can better get at their especial work in soil making Then as the mosses and lichens grow and die In their turn they make malte true soil and prepare the way for other plants which grow upon their mould for now the soil formed partly of or organic organic organic ganic materials will support plants of larger size Here in la the arid arld west you ou will see seethe Seethe seethe the alum root a small saxifrage with red leaves and a of or pretty pinkish flowers follow following followIng followIng ing close upon the mosses and lichens Look up along the sides of any of our canyon cliffs and you will see this lit little little littIe tle tIe plant in every rock crevice in which it can find a foothold Then come small grasses and other plants plant or shrubs which prepare the way for tor larger and larger kinds until the firs pines and cedars put in an appearance and after them the maple willow cottonwood box elder etc Lessons on Lichens Perhaps no better objects can be had for tor the teaching of real physical geog geography geography I raphy than mountain rocks covered with lichens The specimEns are easily found they are curious looking and I often beautiful the lessons they l lare are not single facts but general laws j The work is well adapted to the ca capacity Capacity of seventh and eighth grade pu pupils pupils pupils pils Materials Six or more different rocks with different kinds of lichens clinging to them Aim To discover the work of the first plant sour soil makers I Preparation A walk over the mountain moun mountain mountain tain side with a rock hammer and I basket to collect specimens I Method Hand the rock specimens to I Ith the th pupils Ask what they see there thereon on Tell them these are arc not mosses mosse which have distinct leaves and stems while these are fiat flat masses of vegetable substance without distinction of leaf stem or root These are lichens which die ate the first among the living agencies that begin the manufacture of soil for tor forthe forthe the growth of other plants What Lichens Are Subject matter for the school lessons on lichens will not be found in ht the textbooks In general it may be said that lichens grow gr w everywhere but are most numerous In this region on the higher mountains probably because they are crowded out by other plants lower down We have said that they come from small bodies called spores that are always floating in the air and are sometimes carried by wind currents in great numbers Scientists have put up wet screens and have caught these ried nod particles Cell groups of algae pollen grains and the spores of all aU sorts of mosses and fungi were soon collect collected ed upon apon the moist surface in the little litte grooves or depressions on the screens If at these Ulese places the small groups cf CC algal cells meet with the ing spores of the fungus the I meshes that grow from the fungus will trill enfold the algae and a sort of oC com cm compound i pound vegetable growth will be he pro produced produced This confederacy of or the tha two 1 small smaIl forms terms growing In union we t term rm rma a lichen which is not truly one plant but two of ot different orders Many lIany of or the spores of ot small fungi may thus grow on rock surfaces wherever wherever wherever ever the tho air all Is not too dry but ot rot fo 50 0 many kinds of algae The different lich lichens lichens lichens ens are sensitive e in respect to their mineral food tood however and different sides of or the same rock often exhibit several sev ral varieties of lichen The w writer riter r has collected in the Uinta ranges as 19 many man perhaps as six different t minds kinas from the various exposures of or un on sine ter terminal t minal minaI projecting mass of The algal cells cens are colored boies nd Impart the various and often otten beautiful hues tr to the rock lichens The fungi un 1 are composed of threadlike urns which enmesh the colored ces ceis ce js The mass nass called caned a lichen is therefore compose 1 I of large numbers of fungi with wit interlacing inter interlacing Interlacing lacing colorless threadlike branches and similar large numbers o of algae composed of quantities of green reen or ar arother 1 other colored cells Groups of Lichens There Thre are five fie groups of oC lichens first those clinging to rocks are called crustaceous lichens These are the kind we speak of here the soil soli mak makers makers makers ers whose work ork Is so conspicuous so L 4 i j jA I V r I A Lichen Aerial A Lichen n Natural Ue Size SUI Natural sue DIZe interesting so Indispensable to our welfare Second are the lich lIeh lichens ens n lich resemble crumpled leaves and stand out to the naked eye like the leaves of or the mallow manow when folded only much smaller A third th rd group called the lichens have stems sterns In lit appearance apP arance like small shrubs A fourth group are called the beard lichens These may ma sometimes be e e seen hanging from the bark of oC old trees A fifth group is called the gelatinous lichens When moist these resemble dark olive green or almost black lumps lum s of wrinkled wrin wrinkled wrinkled kled or wavy jelly jell All An of or these have havethe havethe the partners algae and arid fungi associated but to the naked eye ee thee the two have every ever appearance of oC being one growth Two Strange Partners The two plants that form the lichen can bt be b distinguished only under the microscope to the naked eye they ther ap ape appear appear pear pear as one plant and are collectedlY called caned a lichen The fungus takes food from the rock for its branches are acid and will eat cat into the hardest stone It takes taken no food from the air The al algae algae algae gae takes food from the air all and water from the fungus which the latter lauer holds in a fashion The algae then works storks these foods up into starch sugar etc as the higher plants do doThe doThe The fungus which rives Jives only on or organic organic ganic material now uses this food made by the algae The living together er of two plants in this manner is called symbiosis The fungus lives upon the algae as a parasite When separated from each other these plants are delicate united they are so hardy I that their distribution ranges from the equator to the pole and they live upon crystalline rocks baked earth the bark burk and in other places w whereon hereon no I 1 other form of plant life is possible In certain Alpine and desert regions lichens form fonn the characteristic vegetation lion tion and in the far north they afford rich pasturage to the reindeer and ca caribou caribou caribou The manna of history may have been lichen showers Ce Certain tain species are still used as food tood in northern countries Litmus and va various various various rious pigments including the famous purple and blue dyes d es of the east are derived from lichens Blown about in masses mases |
