MANURES FOE THE QUINCE. 39 



Accepting the theory of the chemists, that " somehow 

 or other plants take nitrogen from the air," it is probable 

 that they take it in the form of ammonia, and not as 

 free nitrogen. But free or combined, it is evident from 

 ' experience that most soils will be improved by the appli- 

 cation of a quantity beyond all that is supplied from the 

 air. The fact that the leaves of plants absorb gases should 

 convince us that they may take nitrogen, either free or 

 combined, though it does not combine very readily with 

 other substances. Lawes and Gilbert, from experiments 

 conducted under glass, concluded that plants could not 

 take up the free nitrogen of the air. Professor Atwood, 

 from experiments conducted in the open air, arrived at 

 the opposite conclusion. 



The supply of phosphoric acid from ground bones is 

 never out of place in the quince orchard ; and if the 

 bones are first treated with sulphuric acid, their action 

 will be more speedy. Bones in lye, or hard wood ashes 

 kept wet for a very long time, will become useful without 

 grinding, as they soften and crumble. 



The quince is a great feeder, and has the faculty of 

 using all kinds of manures. "When I plant trees I fill 

 the large holes with rich earth. The chip dirt of the 

 wood pile mixed with the top soil of the hole is good. 

 The surface soil of the poultry-yard to the depth of two 

 or three inches is excellent. Road wash from the gutters 

 of the highway does well ; and better still are the glean- 

 ings of the street gutters of the village. Trees well set in 

 these rich earths grow well to a bearing age, when they 

 should be annually supplied with plenty of good manure. 

 Their annual growth is a safe guide to needed treatment. 

 If the shoots grow less than a foot every year, they need 

 feeding or pruning, and probably both. Manure may 

 be applied to the trees by all the usual methods at 

 any season of the year, but better in the fall and spring 

 than late in summer. Old and feeble trees have been 



