26 AGRICULTURAL AND MECHANICAL COLLEGE OF TEXAS. 



ing for tree wounds. Liquid asphaltum, and preparations containing 

 it, are also efficient dressings, but they must be applied when hot. A 

 good grade of heavy lead paint will be found to give good results. In 

 any event the dressing must be renewed from time to time if checking, 

 due to the drying out of the wounded tissue, exposes the wood surface. 



In a plantation the trees will prune themselves to a limited extent, 

 but some species when planted for fence post material should be arti- 

 ficially pruned in order to secure clear stems. One may remove side 

 branches to the desired height but care should be exercised to make 

 the cuts clean and not to prune so heavily .that the future growth of 

 the tree is lessened. In a shelterbelt the trees should not be pruned, 

 as density is the main requisite. Sprouts should be removed from the 

 base of a tree in any type of plantation. 



Street trees are particularly liable to outside injuries. Such injuries 

 when caused by horse bites, vehicles or any outside influence may be 

 prevented by surrounding the tree with a suitable guard of wire, wood 

 or iron. In many cities iron gratings are placed over the openings at 

 the base of the trees to prevent injury by continual trampling of the 

 soil. Overhead wiring often rubs the limbs and causes serious injury 

 both by bark abrasions and the effect of electric currents A strip of 

 wood placed on the limb at the point of contact will prevent such injury. 

 Eaising or lowering grades around established trees will probably result 

 in their death by diminishing the supply of water and air or by ex- 

 posure. When filling around trees use rocks for the first few layers 

 and then cover these with soil or else build up a wall around the trees, 

 leaving an air space of a foot or more between. When grades are low-, 

 ered there is probably no remedy except the replanting of such trees 

 as are not too large. Gas from leaking mains will soon impregnate 

 the soil around the roots and kill most trees. By stopping the leak, 

 removing the gas saturated soil and replacing it with fresh material 

 the tree may be saved if the injury is not too serious. 



When parts of a tree are diseased or wounded reasonable tree repair 

 is justified provided the value of the tree warrants the expense. Wounds 

 should be creosoted and tarred, but diseased portions of the tree should 

 be thoroughly cleaned and filled with cement or asphaltum. Each seri- 

 ous case usually demands a distinct method of handling and for this 

 reason one should avoid fakers and never trust the future welfare of 

 his tree to any but competent operators. 



Insect and fungus enemies are everywhere present and constant watch- 

 fulness is necessary to protect the trees. Since fungi gain entrance 

 principally through wounded surfaces protecting the trees from out- 

 side injuries will generally prevent this trouble. Insects present a more 

 difficult problem. The insect enemies of a tree may be grouped into 

 three general divisions the leaf eaters, the sucking insects and the 

 wood borers and because of their entirely different feeding habits each 

 group requires special methods of control. The time when the insect 

 is most vulnerable usually differs for each group and further compli- 

 cates the situation. In general, spraying with an arsenate of lead solu- 

 tion (one pound to ten gallons of water) will effectually control leaf 



