LIMING AND THE NITROGEN PBOBLEM 301 



been heavily manured, its application on peat or muck may be 

 advisable. Some truck growers have found potash fertilizers to 

 be quite necessary to reinforce the manure. 



The use of manure greatly increases the weed problem. In case 

 of corn, weed control can be much facilitated when the crop is 

 planted in checked rows to permit of more thorough cultivation. 

 Because of the weed problem, many farmers much prefer the use 

 of commercial fertilizers entirely, especially for general farm crops. 



Wood Ashes Are Valuable. — Unleached wood ashes apphed 

 at the rate of from one to two tons^ to the acre give most excellent 

 results on acid mucks and peats, chiefly because of the potash and 

 carbonate of lime they contain. Results secured through the use 

 of wood ashes on some acid peats could not be duplicated by any 

 mixtm^e of conmaercial fertilizers. 



Liming and the Nitrogen Problem. — ^Even though peat and 

 muck soils contain nitrogen in abundance, some crops growing on 

 these soils suffer for want of this element. It may be advisable 

 at times to apply nitrogen in the form of nitrate of soda as a top- 

 dressing at the rate of 50 to 100 pounds to the acre to a crop like 

 onions, when it shows the need of it by turning yellow. This per- 

 haps explains why mixed fertilizers and manure are much preferred 

 by truck growers. 



A nitrogen deficiency may occur as a result of four conditions, 

 viz. : (a) The soil may be too cold to favor decay and nitrification; 

 (6) decomposition may be too slow because of the nature of the- 

 organic matter; (c) strong acidity may hinder the formation of 

 available nitrogen; (d) there may be a lack of nitrifying organ- 

 isms (Chapter XI). 



Nitrification in strongly acid soils is greatly promoted through 

 liming. Finely pulverized limestone or any other finely divided 

 lime may be used. The use of agricultural lime is particularly 

 necessary in fitting acid peats or mucks for truck growing. The 

 addition of lime not only favors nitrification, but it renders the 

 phosphorus more available as well (Chapter XIII). 



It is thought that the particularly beneficial effect of manure 

 on many marsh soils is due in part to helpful organisms which 

 are added with the manure. Horse manure is especially good in 

 this respect. Peat lands which are pastured a few years before 

 breaking are much improved both in their physical condition and 

 in their productive power. 



2 When, containing 30 to 40 per cent moisture. 



