THE TREES 39 



While tlie roots are spreading out under the 

 ground in search of water which is taken up into the 

 leaves, the leaves themselves, besides making over 

 the water-food into sap, help to provide the roots 

 with water. For they are arranged like the shingles 

 on the roof of a house and shed the rain-water from 

 the trees so that it will fall upon the ground directly 

 over the place where the finest rootlets, with the most 

 active mouths, are growing. Isn't it wonderful how 

 a tree is planned? The most active rootlets are 

 directly under the place where the leaves shed the 

 water. The tree cannot go about to get its food and 

 drink, so by dripping rain to the ground just over its 

 rootlets the tree helps itself to get the needed supply 

 of water. 



Upon the ground near the trunk of the tree, where 

 the older roots carry the water instead of sucking it 

 up, the rain does not fall in great quantities. You 

 have seen the dry places left on the sidewalk 

 near the trunk of a tree when it has rained; and 

 you know how the rain will beat down upon your 

 umbrella from the leaves at the outer edge [of the 

 tree. 



Some leaves, like those of the oak and maple, are 

 smooth and glossy, and shed the water quickly, and 

 some are hairy like the mullein, where the water 

 stands upon the leaf in great drops. Too much water 

 would interfere with the work of the leaf by clogging 

 up the tiny pores through which it breathes, and so 

 most of the breathing is done by the under side. 



Have you ever noticed how different the under side 

 of a leaf is from the upper side? The color is differ- 



