SHADE TREES. 



187 



ment and holds the guard in place. The use of any guard around trees 

 is more or less of a nuisance, but at the present time they have to be 

 applied to street trees. Planting inside of the sidewalk or on wide 

 tree belts will obviate much of the use of tree guards 

 in the future. 



uij 





Fertilizing Trees. 



Trees, like agricultural crops, respond to tillage and 

 treatment with fertilizers and manures, but there are only 

 meager data relative to the specific effects of the various 

 chemical constituents in fertilizers on shade trees. From 

 what is known regarding their effects on other crops, and 

 from their limited use on trees and shrubs, it is evident that 

 they may be applied with a reasonable degree of success. 



Wood ashes have been used to some extent for treating 

 shade trees, also bone meal, nitrate of soda and potash in 

 the form of muriate or sulfate. Any good complete fer- 

 tilizers, such as those adapted to lawns, should prove 

 valuable for trees. Wood ashes, which are not so easily 

 obtained as "formerly, are of benefit to lawns, and there is 

 no reason why they should not prove suitable for trees. 

 A certain amount of nitrate of soda, at the rate of 150 to 

 200 pounds per acre, may be used to good advantage, but 

 care should always be used not to apply it too freely. 

 The nitrate of soda stimulates wood production, and, like 

 Ume, helps to give a deeper color to the foliage; but an 

 excess produces symptoms of malnutrition in many crops 

 which usually takes the form of an abnormal development of 

 foliage. Bone meal is slow to become available, but it 

 does not injure plants when applied freely, and makes a 

 good fertihzer. Pulverized sheep and cow manure are 

 valuable lawn fertihzers, and even though the price is 

 rather high for the plant food contained, they supplj' organic 

 matter and therefore have an especially beneficial effect on 

 the soil. They can be applied freely without danger of 

 harm. 



While trees will respond favorably to judicious treatment ^vith fertilizers, 

 it must be borne in mind that no fertilizer can take the place of cul- 

 tivation. Fertilizers should be applied where the feeding roots are located, 

 and these are confined largely to an area corresponding with the spread 

 of the foliage and not close to the trunk of the tree, as imagined by many 

 persons. This also holds true for tillage, i.e., the whole area surrounding 

 the tree should be cultivated to some distance beyond the spread of the 

 foliage. As the tree develops in size the smaller feeding roots become 

 less abundant near the base of the tree, although cultivation and feeding 

 have a marked tendency to induce root development wherever they are 



Fig. 60. — Clin, 

 ton tree guard, 

 with hose pro- 

 tection at top. 



