Experiments in the Growth of Clover. 363 



One hundred pounds of the pure ground limestone is equivalent 

 to 56 pounds of quick-lime, as the limestone loses about 44 per cent, 

 when burned. If impure it loses less. When quick-lime is water- 

 slaked, 56 pounds becomes 74. Fifty-six pounds of quick-lime there- 

 fore contains as much lime as 74 pounds of water-slaked lime or as 

 100 pounds of limestone or air-slaked lime. The advantages of the 

 ground forms are that they may be distributed with a manure spreader 

 or with a fertilizer drill, but the drill will have to go over the land 

 several times in order to get on enough. The agricultural quick-lime is 

 usually cheapest. It can be purchased for $2.25 to $5.00 a ton. 



Wood ashes contain about one-third lime. The striking benefit to 

 clover from using wood ashes is probably due more to the lime than to 

 the potash. 



Applications of lime. — About 25 bushels or one ton per acre is a good 

 application. The application may need to be repeated in a few years. 

 Formerly much larger applications were made. 



There are many conflicting reports as to the benefit of lime. Many 

 regions have taken it up, abandoned it and later come to use it once more. 

 The explanation is that with the amounts applied there was enough to 

 last a considerable time. 



Lime has a greater effect the second year than it does the first. It 

 is probable that in all these experiments its results would have been 

 more striking if it had been applied a year before seeding. All liming 

 should be done well in advance of the time of seeding clover, preferably 

 with the preceding crop, so that it may have time to get well mixed 

 with the soil. When quick-lime is applied it may be left in the field in 

 small piles where it will partly slake before spreading. 



Relation of crops to lime. There is a very decided difference in the 

 lime requirements of different crops. Alfalfa and clover need more 

 lime than do any of the other common farm crops. These may show a 

 benefit from the use of lime when timothy, corn and wheat are not 

 helped. Timothy may fail for lack of lime where red-top thrives. 



How to tell the need of lime. — One of the most common indications 

 of the need of lime is the failure of red clover on soils where it once grew. 

 This is generally due to the exhaustion of lime. If red clover fails and 

 red-top thrives we should certainly make a test of lime. Clover some- 

 times fails because of the root-borer, but in this case it does not fail 

 until it has produced the first crop of hay. In some regions it fails 

 because of disease (anthracnose) , but in this case it makes a good growth 

 until the disease attacks it. If clover and alfalfa produce good crops 

 lime will not be needed for any common crops. In case there is any 



