PLANTS AEE INFLUENCED BY SOIL 207 



part of the plant -substance is water. The water is not 

 only itself plant -food, but it carries other foods into the 

 plant and transports them from tissue to tissue. However 

 rich a soil may be in mineral plant -foods, it is inert if it 

 contains no moisture. The character of the plant is often 

 determined more ~by the moisture in the soil than ly all the 

 other food materials. Note how rank the plants are in low 

 places. Observe how the weeds grow about the barn where 



355. "Lodged" oats. On rich ground the grain is often broken by wind and rain, 

 the plants having grown so heavy as to be unable to support themselves. 



the soil is not only rich but where moisture is distributed 

 from the eaves. Contrast with these instances the puny 

 plants which grow in dry places. In dry countries irriga- 

 tion is employed to make plants grow vigorously. In 

 moist and rich soil plants may grow so fast and so tall 

 as not to be able to withstand the wind, as in Fig. 355. 



347. PLANTS ARE INFLUENCED BY THE EXPOSURE OF THE 

 PLACE IN WHICH THEY GROW. The particular site or out- 

 look is known as the exposure or aspect. The exposure, 

 for instance, may be southward, eastward, bleak, warm, 



