382 HORTICULTURE, FORESTRY, FLORICULTURE 



Russian mulberry, osage orange, persimmon, and shittimwood. 

 These lists do not include all of the best timber trees that might be 

 grown in the Middle West, for many valuable timber trees will not 

 endure such severe exposure as a windbreak is subject to. 



In the establishment of a windbreak wisdom is required in the 

 placing of the different species. A windbreak composed of more 

 than one species is usually the most effective. An excellent method 

 of arrangement is to place the shortest trees in the outside row 

 (toward the prevailing wind), to plant a somewhat taller species 

 next to them, and to place the tallest trees in a third row on the side 

 adjacent to the buildings or the area which is to be protected. This 

 causes the wind to strike the trees as it would strike the face of a 

 steep hill ; deflecting its course upward. If the tallest trees of the third 

 row consist of a flexible species, such as cottonwood, European larch, 

 white willow, or honey locust, they will bend before the wind, and 

 act as a cushion to deflect it upward and over the object to be pro- 

 tected. A satisfactory windbreak 5 rods in width, for the protection 

 of the north and west sides of a farmstead and adapted to Minnesota 

 and the Dakotas, is as follows: Plant 13 rows of trees, parallel to one 

 another and 6 feet 10 inches apart. The first two rows on the north 

 and west edges of the belts should consist of Russian wild olive, the 

 third and fourth rows of arborvitse, the fifth and sixth rows of box- 

 elder, the seventh and eighth rows of white elm, the ninth and tenth 

 rows of white willow, and the remaining three rows of common cot- 

 tonwood. Such a plantation, when mature, will appear like a wall 

 with a sloping top, the highest side being where the cottonwoods are 

 planted. 



Carrying out this same principle for Oklahoma and Texas, with 

 a change in the position of the plantations to afford protection from 

 southwest winds, the following method is advised : The first two rows 

 on the south and west edges of the belts should consist of Russian 

 mulberry or Osage orange, the third and fourth rows of Chinese 

 arborvitse, the fifth and sixth rows of black locust, the seventh and 

 eighth rows of green ash, the ninth and tenth rows of white elm, 

 and the remaining three rows of honey locust or common cotton- 

 wood. 



In southern California, where the damaging winds come from 

 opposite points of the compass (from both the southwest and north- 

 east), a good plan for a windbreak is one in which the tallest, most 

 flexible trees will be in the center rows, so that the species on either 

 side will slope downward toward the outside edges of the belt. For 

 such a windbreak 2 1 /2 rods wide and consisting of 7 rows of trees, 

 the following arrangement may be suggested : Eucalyptus of the spe- 

 cies best adapted to the site should form the three rows in the middle 

 of the belt, the next row toward the outside on each side should be of 

 Monterey pine (Pinus radiata) , and the two rows occupying the two 

 edges of the belt should be Monterey cypress (Cupressus macro- 

 carpa.) This same arrangement may be used on a belt 5 rods wide 

 by doubling the number of rows of pine and cypress and increasing 

 the gum to five rows. In order to construct a windbreak in Califor- 



