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JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



especially after every rain. In ordinary seasons the cultivation should 

 continue until the autumn, hut in seasons of excessive rainfall the cultiva- 

 tion may stop late in the summer to givo the wood a chance to ripen for 

 winter. 



In dry seasons cultivation is more imperative than in wet. As the 

 trees become large enough to shade the ground, which they will do very 

 quiekly if well tended, less cultivation will be required after four or five 

 years, when they will need but little. In most cases it can be done away 

 with entirely ; a good mulch of old straw will meet all requirements. 



During the first and socond years the trees will be benefited by cutting 

 off the side branches, to keep them from forking and to force an upward 

 growth. After that they should shade each other enough, so that side 

 branches will not form. This work may be done in the spring or summer, 

 not later than July or in the late autumn. Pruning late in the summer 

 forces ii late growth that will not mature before winter. 



If left to themselves, no matter how thickly planted, the stronger 

 trees gradually out-top the weaker ones, and thus Nature does her own 

 thinning. However, better results are obtained by thinning out the nurse 

 trees when the trees become crowded : these may be used for planting 

 elsewhere. This haves the trees standing four by eight feet apart, and 

 in time these will need further thinning. 



List of trees for timber plantation, with description, follows, including : 

 White Ash, American Elm, Basswood, Silver Maple, White Willow, 

 Golden Russian Willow, Box Elder, Burr Oak. White Poplar, Hackberry, 

 American White Birch. 



For street planting the Elm is usually looked upon as the best tree, 

 though at the present time the Box Elder and the Cottonwood are more 

 extensively used in North Dakota. The Elm combined with the Carolina 

 Poplar and Box Elder make a good combination. On the outside of the 

 walk, plant the Carolina Poplar and Elm alternately, leaving twenty feet 

 between the trees ; on the inside of the walk, plant the Box Elders opposite 

 the Poplars, At the end of fifteen or twenty years the Poplars should be 

 removed, leaving the Elm and Box Elder alternating on opposite sides of 

 the walk, with a space of forty feet between the trees of each row, and a 

 tree for every twenty feet along the walk. 



Trees for street planting should be nursery-grown if possible, and in 

 all cases should be headed high ; the trunks should be straight, and two 

 inches or more in diameter, except Carolina Poplars, which may be smaller. 

 It is difficult for very small trees of most varieties to grow tall and 

 symmetrical when set in an open and exposed place ; they should 

 preferably be grown in the nursery long enough to give them an established 

 form and character. 



In order to prevent the trees, when old, drooping and getting in the 

 way, the lower branches should be cut away while small. This process 

 increases the rate of growth of the upper and outer branches, and gives 

 what is needed, a tall spreading tree. 



The Elm has a tendency to an irregular or even sprawling habit of 

 growth ; this should be corrected by cutting back the extending branches, 

 making the top symmetrical. The typical street tree is one headed high 

 enough not to interfere with traffic, and to allow an open view between 



