concerning one of nature's wheels, such as soils, or water, or birds, or 

 wildflowers; but, for real understanding we must consider the total 

 landscape. Plants can be only the starting point, certainly not an end. 



The functions of plants as society feels them is our concern here. 

 Let us pre-view some of the obvious functions of vegetation, and some 

 not so obvious. 



Without plants there could be no people. 



Without plants the whole earth would be a desert. Man is a great 

 manufacturer, and through the misapplication of his power he has 

 manufactured- well over 50,000 square miles of desert in the United 

 States. He did it by preventing plants from functioning. 



Without plants there would be no humus-laden topsoil, no pro- 

 ductivity worth mentioning. 



Without the continuous service of plants, animals would exhaust 

 the oxygen of the air. 



Without plants there would be few reliable springs, few constant 

 streams, few clear rivers, few long lived lakes. 



Without plants past and present there would be no great indus- 

 trial regions depending on freshwater, no cities, no coal, no oil, no gas. 



And, let us repeat, without plants there could be no people, no you 

 and I. 



We have in these statements considered plants at the zero point. ^ 

 As we move the amount of vegetation upward toward the maximum, 

 the related factors move upward with it, until we have the richest 

 possible natural environment such as the frontiers man found, 

 and such as formed the basis of this richest of nations. We may go 

 even farther, and on certain areas exceed nature as by irrigating 

 arid lands or supplying missing soil minerals in certain regions. 



Today, the maximum vegetation is only a memory on vast acreages 

 of our country. The headaches of man came thick and fast when it 

 dropped to the fifty per cent mark or thereabout. 



A single phrase plant deficiency will help answer all the fol- 

 lowing questions, each of which indicates a flaw in the social order of 

 in an. 



1. What causes our streams to be muddy? 



2. Why do once permanently flowing streams become intermit- 

 tent streams with alternate floods and dry beds? 



3. What makes people think the climate is getting drier? 



4. Why are we forced to spend, above and beyond the natural 

 necessity, hundreds of millions on flood control? 



5. Why are new flood crest records being set from time to time ? 

 (I. Why do reservoirs for water supply, power, navigation and 



recreation fill up with mud ? 



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