THE USE OF FERTILIZERS 209 



phosphoric acid is also likely to be effective. For such 

 crops as clover and alfalfa there should always be an ample 

 supply of lime, without which these crops cannot be prof- 

 itably grown. 



265. Root crops. — Most of the root crops remove very 

 large quantities of plant-food materials from the soil, when 

 these are present in available form. Like corn they have a 

 long growing season and the slowly acting fertilizers or farm 

 manure are well adapted to their use. A complete fertilizer 

 in rather large quantity will usually bring a response in 

 yield. For sugar beets the proportion of potash should be 

 high, and for table beets and carrots there should be more 

 nitrogen than for the other roots. 



266. Vegetables. — In raising some kinds of vegetables, 

 the object is to produce a rapid growth of leaves and stalks 

 rather than fruit or seeds, and with these kinds growth should 

 often be made in the early spring. Therefore, for crops 

 like lettuce, radishes and asparagus a soluble form of nitro- 

 gen is very desirable. For crops that are raised later 

 in the season a smaller proportion of nitrogen may be used, 

 and for the more slowly growing kinds of vegetables the less 

 soluble fertilizers may be applied. For all vegetables farm 

 manure or other organic manure should be generously used, 

 as it keeps the soil in a mechanical condition favorable to 

 retention of moisture, which vegetables require in large 

 quantities, and it also supplies needed fertility. The very 

 intensive culture employed in the production of vegetables 

 necessitates the use of much greater quantities of fertilizers 

 and farm manure than are used for field crops, and the great 

 value of the product justifies the practice. 



267. Orchards. — In manuring orchards, it is the aim 

 to maintain a continuous supply of nutrients available to 

 the plants, but not sufficient for stimulation, except during 

 the early life of the tree, when rapid growth of wood is 



