The accompanying cut (No. 1) was made from samples 

 taken on June 21, 1910, from a field of oats growing on the 

 station grounds at Fargo. Fig. 1 represents the growth 

 taken six rods north from a windbreak twenty-seven feet 

 high, and fig. 2 is a fair average of the growth twenty rods 

 north. The land has received the same treatment for the 

 last five years. Previous to that the land on which number 

 1 was grown had a crop of clover, which may have made 

 some difference in its favor. 



Awaiting further evidence upon this question we can at 

 least be sure of the general proposition that hot winds are 

 damaging to crops of all kinds and that trees are more or lesr 

 effective in stopping such winds. 



The injurious effects of windbreaks result only when 

 orchard fruits, particularly plums and apples, are so closely 

 enclosed by heavy planting as to prevent a free circulation 

 of air. This condition may favor the development of certain 

 diseases, like apple blight and plum pocket, tho at the present 

 rate of tree planting in North Dakota there is little need to 

 take alarm on that account. 



KINDS OF TREES 



An ideal tree for windbreaks is one of dense, rapid growth, 

 that is at the same time hardy and long-lived. As it is impos- 

 sible to get all of these qualities in perfect degree in any one spe- 

 cies, it is usually advisable to use a combination of two or three 

 different kinds to get the best results. For instance, the cot- 

 tonwood is hardy and grows rapidly, but it is not long-lived 

 when planted thickly and its growth is not dense enough to 

 do much toward checking the wind. The Norway poplar and 

 the Carolina poplar being both forms of the cottonwood, are 

 open to the same objections. They may be planted in single 

 rows not nearer than twelve feet to the other trees to give 

 height to the windbreak, while the slower growing and more 

 permanent species are getting started. For this purpose they 

 should be set eight feet apart, removing every other tree at 

 the end of five or six years. 



Certain strains of the*balm-of-Gilead are even better for 

 this purpose, as the growth is fully as rapid and more dense. 

 Other forms of this species are small and weak in growth and 

 sucker badly, making them unfit for any kind of planting. 



