We have, finally, to consider through what agency the proposed cultivation of trees in the city of New York can be accomplished most rapidly and successfully. Three methods may be suggested, viz.: 1. Encourage citizens each to plant and cultivate trees on his own premises. 2. Organize voluntary "tree-planting associations," which shall aid citizens or undertake to do the work at a minimum cost. 3. Place the work under the entire supervision and jurisdiction of public authority. The first method has been on trial from the foundation of the city, and its results are a few stunted apologies for trees which are useless for sanitary purposes and unsightly for ornamentation. The average citizen is entirely incompetent either to select the proper tree or to cultivate it when planted. Tree-planting associations have proved useful agencies in exciting a popular interest in the subject, and in aiding citizens in the selection of suitable trees and in cultivating them. The Tree-Planting and Fountain Society of Brooklyn, under the very able management of its accomplished secretary, Prof. Lewis Collins, is a model organization of the kind, and has accomplished a vast amount of good in this field in that city. But it may well be questioned if we have not reached a period of sanitary reform in cities when a work of the kind we contemplate in New York should not be undertaken by the strong arm of the city government, as a matter of public policy, and carried steadily forward to its completion. The growth of the greater city is far too rapid in every direction to await the slow movements of the people under the pressure of voluntary organizations. The best work can be done in those outlying districts where the streets are as yet but sparsely built upon, and the soil has been undisturbed. Again, it is of the utmost importance that a work of this kind, which will largely prove one of city ornamentation, should be under the exclusive direction of a skilled central authority having ample power and means to harmonize every feature of the work from the center of the city to its remotest limits. Finally, the successful cultivation of trees and other vegetation in our streets can be successfully carried on only by experts in the art of tree culture, who devote their entire time and energies to these duties, and are sustained by the power of the city government. Mr. Frederick Law Olmstead remarks, "Not one in a hundred of all that may have been planted in the streets of our American cities in the last fifty years has had such treatment that its species would come to be if properly planted and cared for." Mr. Richards, in the paper referred to on Tree Planting in the Streets of Washington, makes the following statement: "The selection, planting, and care of all trees in the streets of Washington are under the direction of the District authorities; individual preferences and private enterprises are not allowed to regulate this improvement, as is generally done in