“Wait a moment,” said the Deacon, “is not 887 lbs. of straw to 4 bushels of grain an unusually large proportion of straw to grain? I have heard you say that 100 lbs. of straw to each bushel of wheat is about the average. And according to this experiment, the carbonate of ammonia produced over 200 lbs. of straw to a bushel of grain. How do you account for this.” “It is a general rule,” said I, “that the heavier the crop, the greater is the proportion of straw to grain. On the no-manure plot, we have, this year, 118 lbs. of straw to a bushel of dressed grain. Taking this as the standard, you will find that the _increase_ from manures is proportionally greater in straw than in grain. Thus in the increase of barn-yard manure, this year, we have about 133 lbs. of straw to a bushel of grain. I do not believe there is any manure that will give us a large crop of grain without a still larger crop of straw. There is considerable difference, in this respect, between different varieties of wheat. Still, I like to see a good growth of straw.” “It is curious,” said the Doctor, “that 3 cwt. of ammonia-salts alone on plots 9 and 10 should produce as much wheat as was obtained from plot 2, where 14 tons of barn-yard manure had been applied two years in succession. I notice that on one plot, the ammonia-salts were applied at once, in the spring, while on the other plot they were sown at four different times--and that the former gave the best results.” The only conclusion to be drawn from this, is, that it is desirable to apply the manure _early_ in the spring--or better still, in the autumn. “You are a great advocate of Peruvian guano,” said the Deacon, “and yet 3 cwt. of Peruvian guano on Plot 13, only produced an increase of two bushels and 643 lbs. of straw per acre. The guano at $60 per ton, would cost $9.00 per acre. This will not pay.” This is an unusually small increase. The reason, probably, is to be found in the fact that the manure and seed were not sown until March, instead of in the autumn. The salts of ammonia are quite soluble and act quickly; while the Peruvian guano has to decompose in the soil, and consequently needs to be applied earlier, especially on clay land. “I do not want you,” said the Deacon, “to dodge the question why an application of 14 tons of farmyard-manure per acre, every year for over thirty years, does not make the land too rich for wheat.” “Possibly,” said I, “on light, sandy soil, such an annual dressing of manure _would_ in the course of a few years make the land too rich for wheat. But on a clayey soil, such is evidently not the case. And the fact is a very important one. When we apply manure, our object should be to make it as available as possible. Nature preserves or conserves the food of plants. The object of agriculture is to use the food of plants for our own advantage.” “Please be a little more definite,” said the Deacon, “for I must confess I do not quite see the significance of your remarks.”