84 THE SOIL OF THE FARM. 



"Without the knowledge of its composition thus acquired, 

 the best Peruvian guano, rich in ammonia, might be ex- 

 travagantly employed upon soils that would be almost 

 equally benefited by the cheaper qualities, of which the 

 phosphates are the chief fertilizing ingredients. Upon 

 light soils, especially, ammoniacal guano may be used 

 wastefully, owing to the little obstruction such soils pre- 

 sent to the escape of its volatile and soluble portions. 

 The full benefit of these will be better secured in the 

 stronger soils, or in composts prepared with the view of 

 their absorption and retention. In such mixtures guano 

 is used most advantageously. Of itself alone, it may 

 furnish all the ingredients required by the plants; but its 

 activity and evanescence need to be checked ; and on ac- 

 count of its caustic quality, care should be taken that it 

 be not brought in direct contact with the seed. 



The quantity of best guano that should be used per 

 acre is generally rated at from three to five hundred 

 pounds, and it should be applied in damp weather so that 

 the rains may gradually diffuse it equally through the 

 soil. No definite rules, however, can be given as to what 

 soil will be most benefited by guano, or as to the neces- 

 sary quantity to be employed. If used in the compost 

 form it should be mixed, previous to sowing, with four 

 times its weight of good soil; which will avert the danger 

 of injury to the seed and effect a more equal distribution 

 of the manure. For grasses and clovers, ten to fifteen 

 hundred pounds of such a mixture should be sown broad- 

 cast in the early spring. This will be equivalent to from 

 two three hundred pounds of the guano. Guano is too 

 soluble to be applied with profit in autumn. 



On corn crops no manure has a more powerful effect 

 than guano. It is used as a top-dressing in spring at the 

 rate of three to four hundred pounds per acre. The 

 stronger the land is, the larger the quantity that can be 

 applied with profit. 



