Additional Papers. 313 



fills in rich top soil around the roots, being careful to work the soil well 

 in among- them and under the butt of the tree. The soil should be moist, 

 but not wet, and free from large stones. Tread the earth or firm it with 

 a rammer as soon as there is two or three inches of soil over the roots', 

 so that there will be no air spaces about them ; if there are air spaces the 

 roots will dry out and the tree will die. Never i)ut stable manure into 

 the holes, as it causes drying out.' If the soil is very dry, water may be 

 put into the hole after the roots are covered, and allowed to soak away 

 before the rest of the soil is put in. 



After the hole is filled, the ground about the tree should be covered 

 with a mulch of straw or coarse stable mianure. This will prevent the 

 soil from baking or drying out. 



Pruning. — After planting the tree, its top should be trimmed back 

 in order that it may develop symmetrically and to counterbalance the loss 

 suffered by the roots. It is better to cut back the side-branches than to 

 cut off the entire top of the tree. The pruning should be done with prun- 

 ing shears or a sharp knife, which will leave a smooth surface and not 

 injure the bark. 



HOW THE TREE GROWS. 



* When once well planted in a favorable location, the tree is generally 

 able to supply itself with the necessary food and to maintain itself by 

 growth. Some of the more important phases of growth may be men- 

 tioned. 



Absorbtion of IVatcr. — The greater part of the supply of water is 

 obtained through the roots from the soil. It is not the large, woody roots 

 which absorb the water, but the fine, fibrous roots. The fine young roots 

 are covered with root hairs which readily absorb water through their thin 

 walls and pass it upward to the tree through the larger roots. The pre- 

 cautions against drying while transplanting are necessitated by the deli- 

 cate structure of these small roots, because they readily lose water through 

 their thin w'alls when exposed to dry air. 



A good mulch of straw or coarse stable manure is usually sufficient to 

 keep the ground moist during the summer. In extremely dry weather, 

 however, the tree should be watered and the ground under the mulch 

 kept loose by stirring it from time to time with a hoe. If there is a 

 heavy sod about the base of the tree, it should be cut away, and some 

 lengths of drain tile be put vertically into the ground several feet from 

 the tree. The water may be advantageously supplied through these tiles ; 

 merely watering the turf does not usually help the tree. 



Transpiration, or the Giving up of Water Throngh the Leaves. — 

 The water which is taken up by the roots rises through the trunk and 



