PRACTICAL POLLENATION 



trees that no longer depend upon insects for the 

 fertilization of their flowers. 



On the other hand there are little cowering 

 plant-waifs that nestle close to the earth and 

 which, in quite a different manner, also assert 

 their independence. 



The trees that have thus revoked the treaty of 

 alliance include such familiar forms as the pine, 

 the oak and the walnut. 



These trees, and a goodly number of their 

 fellows, long ago declared against further coop- 

 eration with the insect, and adopted the method 

 of producing large quantities of pollen and 

 scattering it in the air to be carried by the wind 

 to the pistillate flowers, which in some cases grow 

 on neighboring branches and in other cases on 

 quite different trees. 



The method is in one sense wasteful, inasmuch 

 as it involves the production of vast quantities of 

 pollen, only an infinitesimal portion of which will 

 ever come in contact with a receptive pistil. And 

 of course the production of this pollen must draw 

 heavily on the energies of the living substance of 

 the tree. 



But on the other hand the tree that thus 

 depends upon the wind rather than upon the 

 insects is under no necessity to develop large 

 and conspicuously painted flowers. Nor need it 



[67] 



