now PLANTS GROW. 165 



clover and Indian corn have any more weight of roots than June grass. They 

 probably do not contain more. 



The roots of a two-year old peach tree in light soil were found seven feet 

 four inches long. In dry light soil, this season, we pulled up one parsnip three 

 feet long, and another three and a half feet long. Small roots were even longer. 



The noted buffalo grass on the dry western prairies is described in the agri- 

 cultural reports at Washington as having very short roots, but Mr. Felker, one 

 of our college students, found they went down seven feet. 



The roots grow best Avhere the best food is to be found. They grow in 

 greater or less quantity in every direction. If one finds good food, it flourishes 

 and sends out numerous branches. Many of the smaller roots of trees die 

 every autumn when the leaves die, and others grow in spring. Near a cherry 

 tree in my yard was a rustic basket without a bottom, filled with rich soil. 

 On removing the basket and earth, cherry roots were found in large numbers 

 near the top of the soil. They had grown full of small branches where the 

 soil was good. Roots in soil will grow up just as well as down. 



Every wood-chopper knows that we can tell the age of trees in our climate 

 by counting the rings or layers of wood on the stump. The cells which make 

 up the stem are larger early in the year than they are near the close of the 

 year or time of growth. 



The stems of Indian corn and of palms do not have much wood in their 

 structure. What they have is in the form of woody bundles or threads scat- 

 tered without order throughout the stem. We cannot tell the age of a palm 

 tree by its diameter, but can tell approximately by its height. The woody axis 

 of a tree is a series of cones placed one over the other, like a lot of funnels, 

 except that the last one is the longest and completely covers all the rest. We 

 may tell the age of a young apple tree or peach tree by counting the scars left 

 each spring where the hard bud-scales fall off. It was once thought that the 

 heart-wood was entirely dead and served no purpose to the tree except to give 

 it support, but later researches show that "living processes" go on to some ex- 

 tent in the heart wood. The growth of wood in our trees is confined entirely 

 to the cambium, or new layer, each year. 



Most flower stalks grow up, but some hang down or bend down and push 

 themselves into the soil to ripen seeds, as do the peanut and some poli/galas a.nd 

 wild beans. 



Still, most, if not all, young stems grow up and the roots turn down. Vari- 

 ous attempts to explain this on mechanical principles have all failed. We can- 

 not tell why they grow as they do any more than we can tell why young ducks 

 take to the water. 



LEAVES 



when very young appear as a little projection of one piece, — as they advance 

 woody bundles or frame work are developed. Leaves have been called the 

 lungs of plants. In a certain way they are a temporary stomach as well as 

 lungs. Yet I have known a graduate in a Greek and Latin course to cut off 

 the leaves from his grape vines to let in the sun to ripen his grapes in Septem- 

 ber. Leaves are a chemical laboratory, a factory to assimilate raw materials 

 ready for plant fabric, — to build up all parts which grow. 



Leaves put the plant in close proximity to the air and light of the sun. They 

 regulate to some extent the escape of water, which comes up from the roots. 



