78 
EASTERN SHADE TREE CONFERENCE 
available nutrients in the lower soil levels together with large quantities 
of water. A combination of the injection method with crowbar feeding 
may be advisable in cases of greatly weakened trees. 
I wish to conclude with a few remarks on the composition of tree 
fertilizers and the rates of feeding. It is apparent that a great diver¬ 
gence of opinion exists upon what constitutes a really satisfactory fer¬ 
tilizer for shade trees. This is not strange and has not been settled for 
crop plants or fruit trees. The materials best suited for one section with 
heavy soils may not be the best adapted for regions with light sandy 
soils. We are all aware of the beneficial effects to be secured from nitro¬ 
genous fertilizers. The requirement for phosphates and potash is less 
firmly established on many soils. When trees growing on a variety of 
soil types and degrees of fertility are to be fertilized it appears that a 
mixed fertilizer is to be preferred. Many complete fertilizers with 15 
to 20 units of plant food should prove satisfactory. The nitrogen con¬ 
tent should be from 5 to 10 per cent. 
The amount of fertilizer to be used depends on the condition of the 
tree, the nature of the soil and seasonal factors. Some of the recom¬ 
mendations made in the Middle West where heavy soils prevail and 
where the summer drought is more common and severe than in the East 
have been found to be excessive in Connecticut. A 10-8-6 fertilizer 
when used at rates based on a pound for each foot in height, branch 
spread and inches of trunk circumference has severely injured and killed 
sapling sugar maples, silver maples and catalpas at the Bartlett Tree 
Research Laboratories. Our findings were that a pound of ‘fertilizer 
per inch of trunk circumference or slightly more was an effective rate. 
The object of shade tree feeding is not to force excessive vegetative 
growth but rather to maintain trees in a good state of growth with 
healthy green foliage so that the trees are able to resist the normal 
unfavorable climatic conditions that prevail in summer and winter and 
to satisfactorily cope with injury and disease. 
TREES ON CITY AND VILLAGE STREETS 
By C. E. Van Fleet, Superintendent of Fire Alarm , Mt. Vernon , N. Y. 
Officers , Members and Guests of The Eastern Shade Tree Conference: 
On behalf of the International Municipal Signal Association origi¬ 
nally known as the International Association of Municipal Electricians, 
organized in 1895 with the object of co-operating in the formulation of 
standards for the safe installation and most efficient operation of munic- 
