42 EXPERIMENTAL FARMS 



1-2 EDWARD VII., A. 1902 



as farmers could copy to advantage in their general practice. On the contrary, to gain 

 the information desired, it has been found necessary to use some fertilizers in extra- 

 vagant quantities, and in other instances to more or less exhaust the soil by a succes- 

 sion of crops of the same sort, practices which in ordinary farming would be detri- 

 mental. Nevertheless, much useful information has been acquired, some of a positive 

 and some of a negative character, by this long-conducted and extensive series of tests. 

 The information now gained from \ear to year throws light in many ways on the ac- 

 tion of fertilizers and is increasingly useful. 



VALUABLE INFORMATION GAINED. 



As results of these trials, it has been shown that barn-yard manure can be most 

 economically used in the fresh or unrotted condition; that fresh manure is equal, ton 

 for ton, in crop-producing power to rotted manure, which, other experiments have 

 shown, loses during the process of rotting about 60 per cent of its weight. In view of 

 the vast importance of making the best possible use of barn-yard manure, it is diffi- 

 cult to estimate the value of this one item of information. 



At the time when these experiments were planned, the opinion was very generally 

 held that untreated mineral phosphate, if very finely ground, was a valuable fertilizer, 

 which gradually gave up its phosphoric acid for the promotion of plant growth. Ten 

 years' experience has shown that mineral phosphate, untreated, is of no value as a 

 fertilizer. 



The use of sulphate of iron, which at the time these tests were begun, was highly 

 recommended by an authority at that time eminent, as a reliable means of producing 

 increased crops, has also been proven to be almost useless for this purpose. 



Common salt, which has long had a reputation with many farmers for its value 

 as a fertilizer for barley, while others disbelieved in its efficacy, has been shown to 

 be a most valuable agent for producing an increased crop of that grain, while it is 

 of much less use when applied to crops of spring wheat or oats. Land plaster or 

 gypsum has also proven to be of some value as a fertilizer for barley, while of very 

 little service for wheat or oats. Some light has also been thrown on the relative useful- 

 ness of single and combined fertilizers. 



CHANGES MADE IN THE EXPERIMENTS. 



After ten years' experience had demonstrated that finely-ground, untreated mineral 

 phosphate was of no value as a fertilizer, its use was discontinued in 1898. Prior to 

 this it had been used in each set of plots in Nos. 4, 5, 6, 7 and in No. 8 also, in all the 

 different series of plots, excepting roots. In 1898 and 1899, similar weights of the 

 Thomas' phosphate was used in place of the mineral phosphate, excepting in plot 6 

 in each series. In this plot the Thomas' phosphate was used in 1898 only. 



After constant cropping for ten or eleven years, it was found that the soil on 

 those plots to which no barn-yard manure had been applied was much depleted of 

 humus, and hence its power of holding moisture had been lessened and the conditions 

 for plant growth, apart from the question of plant food, had on this account become 

 less favourable. In 1899 the experiments were modified and an effort made to restore 

 some proportion of the humus and at the same time gain further information as to 

 the value of clover as a collector of plant food. In the spring of that year ten pounds 

 of red clover seed per acre was sown with the grain on all the plots of wheat, barley and 

 oats. The clover seed germinated well, and after the grain was cut the young clover 

 plants made rapid growth, and by the middle of October there was a thick mat of 

 foliage varying in height and density on the different plots, which was ploughed under. 

 The growing of carrots and potatoes on one half of the cereal plots has been discon- 



