THE FUNGI 



285 



parasites. The order of the government to destroy the bar- 

 berry bushes during the late war is an instance in point. These 

 barberries were known to be infected by one phase of the wheat 

 rust, which winters on wheat straw or stubble. By destroying 

 the barberry the government hoped to eradicate this dangerous 

 pest. Recent orders of the government, looking toward the con- 

 trol of shipments of bulbs and nursery stock from Holland and 



INCOME 



I. FROM SUN 

 ENERGVv ' 



2. FROM AIR V 



CO* \. 



OUTGO 



NON-GREEN ORGANISMS 



GREEN PLANT 



FIG. 158. The organic food cycle 



other European countries, are interesting indications of the 

 awakening of the country to the great danger and commercial 

 importance of fungous diseases to our ornamental and food plants. 



THE ORGANIC FOOD CYCLE 



From what has been learned concerning the life of the fungi 

 the student is prepared to understand more clearly the relative 

 position of the fungi and the green plants as regards the food 

 supply of all organic life (Fig. 158). We have seen that the 



