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Canadian Forestry Journal, November, 19/9 



Trees, like other growing things, depend on 

 moisture. Given sufficient moisture we could 

 grow trees right among the grass of the open 

 prairie. Under irrigation, where there is plenty 

 of moisture there is no difficulty. 



One of our best shelter strips runs for half 

 a mile along one of our main laterals. It con- 

 sists of a row of maple and cottonwood and 

 was planted in 1912. Two men planted it in a 

 day and it was cultivated twice m 1912, and 

 twice in 1913. Since then it has had no at- 

 tention, not even being flooded with water. 

 The ditch runs only about half a dozen times 

 a year and then only for two or three days at 

 a time. The cottonwoods are some six feet 

 from the edge of the ditch and yet the belt is 

 now 20 to 24 feet in height and many of the 

 trees are 8 inches in diameter. We got those 

 young cottonwoods, about two feet high from 

 the river bottom and there was nothing to pre- 

 vent our neighbors from doing the same at the 

 same time. If they had, or even if two or three 

 had, what a beautiful country there would now 

 be and how well sheltered. 



We were not alone in this planting, for Mr. 

 Pawson, about two miles away, had planted a 

 similar belt a few years previous, which is now 

 nearer thirty than twenty feet high. This belt 

 is also along a permanent ditch bank and has 

 cost nothing to maintain since it was planted. 

 It makes a fine showing from all over the coun- 

 try and it seems to me some effort should be 

 made to induce other people to do the same. 



There would be no extra waste of land as 

 there are usually 6 to 8 feet of waste land any- 

 way alongside these ditches. Planted on one 

 bank , there would be plenty of room to scour 

 the ditches when necessary. 



When irrigation began in Alberta, I was in- 

 formed by people who came from irrigated dis- 

 tricts in the south that trees would soon spread 

 all along the ditch banks thhough seed being 

 washed down with the water, but it seems our 

 water flows through a treeless region and there 

 is very little indication of anything of natural 

 tree growth in any of the ditches. 



The planting of cuttings and seedlings will be 

 necessary. 



EDUCATION THE SECREl . 



A vigorous campaign of education carried on 

 among our irrigators and perhaps a few prizes 

 offered for the best half-mile of such shelters 

 two or three years old would stimulate tree- 

 planting in the irrigated sections and go a long 

 way towards stopping trouble from wind injury. 



A neighbor remarked the other day that in 1914 

 the only oats he had were those sheltered in the 

 lee of a fill about three ^eet high across liis 

 land. All the rest were blown away when six 

 inches high. The three foot bank sheltered 

 some twenty or thirty yards and I could not help 

 thinking if he had had as good a shelter belt 

 as Mr. Pawson's, 30 feet high, how mucn more 

 he would have harvested. Certainly much more 

 than would have paid for the whole cost of the 

 shelter belt, several times over. 



Trees pay on the farm, and with irrigation, 

 tree growing is easy. All it wants is education 

 to set men thinking in the right direction. Tree 

 growing on the dry farm is a different pro- 

 position. 



TREES ON A DRY FARM. 



Here, as elsewhere, the main question is 

 water, and the only water available is that 

 from the natural precipitation. 



Fortunately, tree crops require only from half 

 to one-third the rainfall that grain crops do so 

 that if we can grow wheat there should be little 

 trouble about trees. There is, however, so little 

 moisture to spare that every effort must be 

 made to preserve what is needed for the use of 

 the trees. In grain growing, as we have seen, 

 this is done by summer fallowing every other 

 year, but trees are a permanent crop and syste- 

 matic summer fallow is impossible. 



PREVENTING WATER LOSSES. 



There are three ways in which water may 

 be lost from the soil: draining away into the 

 subsoil and so into springs, transpiration 

 through the leaves of grass, trees, and other 

 plants, and direct evaporation from the surface. 

 In this country we have no loss from subsoil 

 drainage, loss by transpiration we must have or 

 trees will die, and the only things left for us 

 IS to do all we can to check evaporation from 

 the surface. 



The two prime evaporative forces are the sun 

 and wind, and if we are to be successful in our 

 farm forestry we must so arrange our planta- 

 tions that the action of these two be checked 

 as much as possible. 



WIDE BELTS AND DENSE FOLIAGE. 



Dense foliage means shade, and therefore the 

 denser we can keep our foliage or forest crown, 

 the less evaporation we will have through the 

 direct rays of the sun. 



A narrow strip of trees, a single row, or even 

 three or four rows allows the wind to pass 

 through almost as easily as if there were no 



