soil, MOIS riRK AND PRKI-ARATION OF SOIL. •; f} 



(^i,') Allow tlicm III slaiul imlil the surface of tlic soil 

 ill can No. I isdiy. WVig-li a^'ain, and compare willi [A. 



{//) Carctully (lit;' down into llic soil of cacli can, and 

 measuie the distance from the snrface to a layer of 

 moist soil. Compare these distances In which can 

 would the contiilions be better adapted to sui-face-feeding 

 plants' In which to deep-feedins: plants? //c?7i' does 

 the water escape ? Out of wliich can has it escaped 

 most slowly ? Most rapidly? Why? In which can the 

 air most freely enter the soil? In outdoor soils of these 

 three conditions, which would noTC allow the water to 

 pass into it least freely ? Which of these soils represent 

 a rolled soil ? Which a loosely tilled soil ? How would 

 a rain affect each of these soils ? Why is it necessary to 

 till the soil about growdng plants as soon as possible 

 after a rain ? What is the condition of soil in the field 

 in early siiring? Flow 

 does early spring plow- 

 ing affect the evapora- 

 tion of soil moisture? 



(/) Compare these 

 mulches, and record 

 your o'u'/i c o n c 1 u s i o n s 

 upon the teachings of 

 this experiment. 



Tillage for surface- 

 feeding roots may be 

 deep when the plants 

 are quite youncr, but''"'- ^f^-— to sho 



^ DEEP AND SUA 



when they have made 

 considerable growth plowing must necessarily 

 be shallow to avoid destroying the roots (Fig. 

 26), which sometimes reach from row to row. 

 Cultivation should not be repeated until the 



26. TO SHOW THE EFFECT OF 



ALLOW TLOWINC;. 



