56 Strawberry-Growing 



results reported from the use of manure, such as running to 

 vines, poor flavor and lack of firmness, are caused by the 

 large amount of available nitrogen that it contains. One 

 ton of fresh horse manure contains about 9.8 pounds of 

 nitrogen, 3.1 pounds of phosphoric acid and 14.9 pounds 

 of potash. This is not a balanced fertilizer for the straw- 

 berry ; it contains too much nitrogen in proportion to the 

 mineral plant-foods. On clay soils, which are usually rich 

 in available potash and phosphoric acid, manuring alone 

 may give excellent results ; but in most cases it is desirable 

 to supplement manuring with applications of potash and 

 phosphoric acid. Another disadvantage, especially with 

 horse manure, is the large number of weed seeds that it 

 contains. This may be overcome, in part, by compost- 

 ing the manure. If fresh manure is used, it should be 

 applied to the preceding crop at least a year before straw- 

 berries are set. Very strawy manure should not be ap- 

 plied at planting time, as it loosens and dries out the soil. 

 The disadvantages of manure are insignificant compared 

 with the benefits. The plant-foods in manures are readily 

 available : they contain bacteria which have a beneficial 

 influence on soil fertility; they increase the water-hold- 

 ing capacity of the soil and improve its texture ; the bene- 

 ficial effect is extended over many years. 



Rate of application. 



In most cases, manure should not be used as a main 

 source of plant-food, but in connection with green- 

 manuring and commercial fertilizers. The application 

 to the acre will depend largely on the cost ; when manure 

 costs over two dollars a ton perhaps the same results 

 can be secured at less expense with green-manures and 

 commercial fertilizers. An application of twelve to 



