Right Use Of Lime In Soil Improvement Part 5

_Lime-Loving Crops._ There are plants which are acid-resistant, giving a good return for fertilization and care when the soil is sour. There are a few kinds of cultivated plants that seem to prefer an acid soil, and to resent lime applications. Most staple crops prefer an alkaline soil, or at least one that has no large requirement, and there are plants that thrive best only in land rich in lime. Not all such plants require more as a component part of their structure, but do have a high percentage in their ash.

_Liming for Alfalfa._ When all other conditions are right, alfalfa thrives or fails according as a soil is rich in lime or is distinctly deficient. It is entirely possible to get fair yields of this legume for a short time from land that is not fully alkaline, but full yields and ability to last for a term of years depend upon a liberal lime supply.

Alfalfa is at home only in a naturally calcareous soil, or one that has been given some of the characteristics of such land by free use of lime. In the case of neutral or slightly acid ground it is good practice to mix four tons of limestone per acre thoroughly with the soil. Such treatment gives greater permanence to the seeding, enabling the plants to compete successfully with the wild gra.s.ses and other weeds that are the chief obstacle to success in the humid climate of our Mississippi valley and eastern states. When this amount of stone is used, the finest grade may not be preferred to material having a considerable percentage of slightly coa.r.s.er grains.

[Ill.u.s.tration: Remarkable Effect of Lime on Sweet Clover at the Ohio Experiment Station]

[Ill.u.s.tration: Sweet Clover Thrives When Lime and Manure Are Supplied, Ohio Experiment Station]

_Red Clover._ When land is in excellent tilth, it may grow red clover satisfactorily while showing a decided lime deficiency. On the other hand, much slightly acid land fails to grow clover, and an application of lime is followed by heavy growths. Red clover is most at home in calcareous soils, and lack of lime is a leading cause of clover failure in this country. Other causes may be important ones in the absence of lime and be overcome when it is present.

_Alsike Clover._ Most legumes like lime, and alsike clover is not an exception, but is far more acid-resistant than the red. It is less valuable, both for soil improvement and for forage, having an inferior root system, but has proved a boon to farmers in areas that have been losing the power to grow red clover. The custom of mixing red and alsike seed has become widespread, and distinctly acid soils are marked in the clover flowering season by the profusion of the distinctive alsike bloom to the exclusion of the red. While there is acid-resistant power, this clover responds to liming.

_Crimson Clover._ Among lime-loving plants crimson clover has a rightful place, but it makes fairly good growth where the lack of lime is marked.

_Bluegra.s.s._ The heaviest bluegra.s.s sods are found where lime is abundant in the soil. This most valuable pasture gra.s.s may withstand the encroachments of weeds for a long time when lime is not abundant, if plant food is not in scant supply, but dependable sods of this gra.s.s are made only in an alkaline soil. Heavy liming of an acid soil pays when a seeding to permanent pasture is made, and old sods on land unfit for tillage may be given a new life by a dressing.

_Crops Favored by Lime._ Nearly all staple farm crops respond to applications given acid soils. Corn, oats, timothy, potatoes and many other crops have considerable power of resistance to acids, but give increased yields when lime is present. Liming is not recommended for potatoes because it furnishes conditions favorable to a disease which attacks this crop. When clover is wanted in a crop rotation with potatoes, it is advisable to apply the lime immediately after the potato crop has been grown, and to use limestone rather than burned lime. Most kinds of vegetables thrive best in an alkaline soil.