TREES AS GOOD CITIZENS 
196 
snugly wrapped around the trunk in a way to fill all the 
crevices of the bark. Over this there should be placed a 
5 inch strip of building tar-paper, tightly drawn and 
securely tacked at its overlapping ends. The sticky 
substance is then applied to this paper. It should be 
renewed when it becomes dry or covered with dust or 
insects, as its stickiness is its one point of efficacy. 
It should not come in contact with the tree, although 
occasionally it is recommended to apply such material 
directly to the trunk high enough to be above persons 
passing. There is danger from a girdling effect due to the 
hardening of the material (Hopkins, U. S. Dept, of Agr.) 
and due to the penetration of possible injurious substances 
in the material. A sticky fly-paper may be used, over 
bands of cotton and with the edges securely bound with 
string. 
Safeguards against insect attacks are as important in 
their way as the application of remedies after the attacks 
have taken hold. Much damage may be prevented by 
advance precautions. Among the most important steps 
of this character is the providing of good cultural condi¬ 
tions and careful attention to all pruning, or accidental 
injuries and cavities. 
Since trees which are strong and healthy are in best 
position to resist insect attacks, it is important that weak¬ 
ened trees should be stimulated by enrichment of the soil. 
This may be accomplished by applying nitrate of soda, 
stable manure, or other fertilizer containing nitrogen. 
This stimulus, combined with pruning and frequent culti¬ 
vation, will produce new vitality and prove helpful in 
enabling a tree to combat its insect enemies with its own 
forces. 
