112 AS CALIFORNIA FLOWERS GROW 



ter if he devastate a mountain side and rob the 

 future generations of food. His moral right lies 

 with his own conscience. California has so small 

 a rainfall that we need to be more careful of our 

 forests than do Oregon, Washington, or our Atlantic 

 sisters. 



Trees really conduce to a greater rainfall. Their 

 millions of cool leaves, elevated above the earth, 

 form a condensing influence of the moisture in the 

 air. You can see how they work if you hold a cold 

 cover over a steaming pot and turn the floating 

 steam into drops of water. The trees themselves 

 send out some moisture into the atmosphere. Have 

 you ever breathed on a looking-glass and seen the 

 moisture that came from your lungs? Well, the 

 leaves of a tree are its lungs, and these billions of 

 lungs are breathing out moisture all the time. If 

 you wish to prove it, place a dry glass over a grow- 

 ing plant, or take a leafy twig and place it through 

 a card, with its stem in a glass of water, and its 

 leaves above the card enclosed by a dry glass. Put 

 it in the sunshine, or even in the light, and see what 

 will happen in an hour's time. 



This habit of the trees keeps the atmosphere near 

 them moderately cool in the heat of the day. How- 

 ever, they do not always lower the temperature, 

 for at night, when the earth is giving out the heat 

 it gained from the sun during the day, the tree foli- 



