48 MANUAL FOR SUGAR GROWERS. 



amounts in the absence of any special information. 

 This mixture should be evenly distributed in proper 

 quantity on the surface of the soil, around and at a 

 short distance from each plant ; this is best done im- 

 mediately before weeding, the operation of weeding 

 tending to distribute the manure and to mix it with 

 the soil. It will be observed that no nitrogen is 

 recommended at this stage. If the land is in good 

 condition, and has been treated in the manner de- 

 scribed at the beginning of this chapter, there will 

 be a sufficient quantity of nitrogen, and much of 

 that nitrogen in the readily available form of ni- 

 trate, already in the soil. In about May or June, or 

 earlier, if the growth of the plant shows lack of vig- 

 our, a light top-dressing of sulphate of ammonia 

 in quantity of about one hundredweight per acre 

 should be applied in the same manner as the super- 

 phosphate and potash, and a second dressing of the 

 same quantity should be given six or eight weeks 

 after the first ; a third dressing is seldom necessary 

 or remunerative. 



It has been stated that ammoniacal manures 

 should not be applied to soils containing more than 

 10 per cent, of carbonate of lime, as there is as- 

 sumed to be a loss of ammonia owing to the con- 

 version of the sulphate or other salt into the vola- 

 tile carbonate of ammonia. The author recently 

 made a series of experiments on two soils, one 

 containing 1.3 per cent, and the other 40 per cent, 

 of carbonate of lime. The soil was placed in a 

 shallow glass dish, to a depth of about an inch 

 and a half, a known quantity of sulphate of ammo- 



