HOW SOILS ARE FORMED.

Dominion, Volume 3, Issue 890, 9 August 1910, Page 8

HOW SOILS ARE FORMED.

■ :"'■■...*'Speaking on the formation of;soils an said at IVildinj;:- >!; , : .;.. .'"The'whole mineral or . inorganic' pbr-' .jfion has. been derived from the gradual '.'•. of rock 'through' thV'uifliiv •encc.of water, frost,'air, heat, and cold; : ithe hardest-of rocks, gradually crumbles 1 ■away.under the influence of. naturo and j-y'whenj blended with decayed vegetable and ■:. animal matter forms. a soil capable of growing: plants. -The soil thus produced '...'':.partakes. of the chemical 'character! auU ■''. icoinposition.'of the'rock from which it. !". fhasibeen derived./If the rock. be . a f'-' jßands'tpne. the soil is sandy, if claystono ;;ttt'is-:inoTe!orless a still clay, if,a lime- . etone-, it is more or less 'calcareous. ■.-:.> "After, the crumbling of.the rocks vari-i .'■: : (Ous;lbw :fdrms.of- vegetable!'- life settle fnpori the mineral fragments, and as they ■■ -fdecay'.become available for future growth; ■•'.■■ rthese.'/processes are. continually repeated And are always in progress, and in this .. fway there gradually accumulates a rich : ' humus.- ■.'•■;;'■:;,. "Fertility :of soils is therefore to -a , jgreat extent due to the organic residues left by previous generations of plants -■'. mixed-with certain mineral -. substances,' . .tho.most important of which are'.phosjphoricacid and potash." : . ' _ •;■,. . :,..