650 THE GARDEN AND FIELD. 



® Dry Farmii\£^ ® 



It will be remtmbercd that the 

 ex-Minister for Lands (X.S.W.), 

 Mr. N. Nielsen, attended the dry 

 fanning conference in America, and 

 acted in other capacities in the 

 United .States, while a member of 

 the Legislative Assembly. In a 

 report to the Premier on dry 

 " farming," he points out that the 

 term " dry areas " is purely a re- 

 lative one, and that the configura- 

 tion of the country, the soil, the 

 natural drainage both on and be- 

 low the surface, the seasons during 

 which the rains fall, and a dozen 

 other considerations come into 

 play in determining the value of 

 any country or part of a country 

 for the growth of economic, plants. 

 Mr. XieLsen deals at length with 

 experiments carried out relative to 

 the amount of water necessary to 

 support the growth of plants by 

 Hellreiger, in Germany, King, in 

 Wisconsin, U.S.A., and also Wid- 

 soe and Merrill, in Utah, U.S.A. 

 Ix>oking at these experiments from' 

 the dr^• farming point of view the 

 following general deductions are 

 made : — 



" I. That under arid or semi- 

 arid conditions it requires from 

 500 lbs. to 800 11)s. of water to 

 produce i lb. of dry matter in th* 

 ordinary crops that may be grown 

 in dry farmmg country. 



" 2. That if wheat is taken as 

 a fair sample of cereal products in 

 dry farming country — that is, one 

 that gives a fair proportion of 

 straw, chafi, and flag to the grain 

 — it is obvious that only about 

 half of the dry matter produced 

 will be grain, as dry land wheat 

 produces about an et^ual weight of 

 straw, flag and chafi to grain. It 

 therefore follows that to produce 



1 lb. of actual grain 1,000 to 

 1^600 lbs. of water is necessary. 

 This means that from' 27 to 43 

 tons of water are necessary to pro- 

 duce one bushel of wheat. 



" 3. That as lin. of water on 

 an acre of land weighs about 

 226,397 ll)s., or, roughly, lol tons, 

 if the whole of this water could be 

 converted into dry matter it would 

 be e<iual to a production of from 



2 1-3 bu.shels to ^% bushels of grain 

 ]>er acre per inch of ramfall, and a 

 toinch rainfall, if all could be 

 stored and used, would produce 

 from 21 to 27 bushels per acre." 



— Limitations. — 



" Of course, it is impossible," Mr. 

 Nielsen adds, to get the benefit 

 ol the whole of the rainfall of the 



3-ear ; part of it falls outside the 

 growing season altogether, and 

 must, to some extent, be elimin- 

 ated from consideration, except, 

 perhaps, to the extent that it can 

 be retained in the soil by fallowing 

 and other forms of scientitic agri- 

 culture. But, allowing that even 

 two-thirds of the total rain is 

 available, mostly by reason of it 

 falling during the growing season, 

 and i)artly by it being stored in the 

 so'U during the off season ; and as- 

 suming as a basis of calculation 

 that the crop only gets the full 

 benefit of two-thirds of this by 

 the employment of all the known 

 sctientific methods of dry farming, 

 a lo-inch rainfall would thus leave 

 for the actual growing use of the 

 grain about 4^ inches of this 

 amount. This should produce from 

 loyi to 16^^ bushels of grain per 

 acre. These figures may be fairly 

 considered as the possibilities of 

 dry farming ir.ethods in parts of 

 the country where the rainfall is 

 10 inches or thereabouts per annum 

 under ordinary conditions. If the 

 mean of these figures is taken, dry 

 farming in a lo-inch rainfall should 

 produce an average of 13^ bushels 

 of grain per acre. This would mean 

 27 bushels in a 20-inch rainfall, and 

 40 bushels in a 30-inch rainfall, if 

 the same iiroportion of the water 

 falling should be conserved.." 



Allowing for the other factors, 

 Mr. Nielsen says : " By the adop- 

 tion of proper dry-farming me- 

 thods on aU the suitable lands of 

 any country where the rainfall is 

 less than 30 inches per year, crops 

 of from 10 to 35 bushels of grain 

 may be expected where now are 

 growut^ from nothdug to perhaps 15 

 bushels." The report points out 

 that in New South Wales^ only 36 

 ])er cent, of the land surface has 

 over 20 inches of annual rainfall, 

 while 64 per cent, has less than 

 that amount, of which 25 per cent, 

 has less than 10 inches annually. 

 In the United States the propor- 

 tions are, roughly, 49 per cent, 

 under 20 inches and 51 per cent, 

 over 20, and of the 49 per cent, 

 under 20 inches 18 per cent, has 

 under 10 inches. 



— Main Principles. — 



The main principles underlying 

 dry farming are the retaining in 

 the soil, not only of the water 

 that falls during the actual growth 

 of the plant, but also a propor- 

 tion of that which fails during the 

 period between harvesting and 



, July, 1913 



sowing., The treatment of the soil 

 that secures this end is the essen- 

 tial basis of all dry -farming opera- 

 tions. Plants wUl not grow with- 

 out water. No amount of fertili- 

 ty in the soil and no amount of 

 commercial fertiliser that may be 

 added will cause plants to grow 

 and ^nature without water. 



— Fallowing. — 



Dry -farming has gone beyond* the 

 experimental stage ; its practical 

 application has been carried into 

 effect more or less in every coun- 

 try in the world. What, is now re- 

 quired to complete, the usefulness is 

 to secure its general adoption by 

 the man on the land. To do this 

 he must be shown first that it is 

 practicable and second that it is 

 profitable. It would be useless to 

 urge its adoption unless it would 

 be shown that the returns justified 

 the extra work involved. With the 

 exception of very exceptional na- 

 tural phenomena, there is no rea- 

 son, except the shortcomings of 

 the farmer himself, why failure of 

 crops should take place in any 

 country where the rainfall is 10 

 inches or over per annum. The 

 value of fallowing land lis not only 

 because it helps to keep the water 

 in the soil, but also because it al- 

 lows the greater jjart of the rain 

 that falls to get into the land and 

 break up the sou into finer parti- 

 cles. Fallowing also prevents the 

 growth of weetis and other useless 

 plants which rob the soil of inuch 

 of the moisture that would other- 

 wise be available for the crop. It 

 should not only consist of a siimple 

 turning over of the soil, though 

 this in itself is very valuable, tint 

 it should be carried out in such a 

 way as to prevent as much as 

 possible the " run-off " of any rain 

 that falls ; ancl made quite ehective 

 in securing the sinking of such rain- 

 fall well into the sub-soil. It should 

 provide for the cultivation of the 

 toi^ portion of the soil to provide 

 a dust mulch (to break the , capil- 

 lary action or surface tension, 

 which draws the moisture from ttio 

 soil upwards) and so prevent eva- 

 poration ; and never be con.sidered 

 suflicicutl}- well done unless it ab- 

 absolutely^ prevents the growth of 

 weeds and, other useless plants. 



To secure these ends it is neces- 

 sary, (1) td plough deeply so as to 

 open up the laud and g'ive the sub- 

 soil a chance to partitnpate in the 

 economy of the, process ; (2) to cul- 

 tivate the top of the ploughed land 

 .so as to secure the dust mulch and 

 the breach of the njiward capillary 

 action of the .soil, and so check 

 evaporation ; (3) to do this after 

 every considerable rain so as to 



