A Farmer’s Notebook HEAVY DEMAND FOR LIME

Southland Times, Issue 24153, 15 June 1940, Page 14

A Farmer’s Notebook HEAVY DEMAND FOR LIME

Capacity Of Works Taxed DIFFICULTIES OF MANUFACTURERS . MEANING OF THE P.H. SCALE Tire demand for lime for agricultural purposes during the past two months has greatly exceeded the capacity of the lime-producing works in Southland. This position has caused a certain amount of criticism chiefly along the line that lime companies should increase the capacity of their works sufficiently to deal effectively with the heavy demand that occurs during the autumn months.

The suggested remedy—on _ first thought—appears to be quite simple from the consumer’s point of view. The manufacturers, however, find that the problem presents many practical and financial difficulties. It is estimated that not more than 10 per cent, of the land in the dairying and fat lamb producing areas have received enough lime to bring them up to the sweet or neutral condition. Also, that not more than 35 per cent, of the land has received more than half of the requirements.

In view of this, and the rapidly growing realization of the position by farmers, it appears logical that an increase in the manufacturing capacity of lime works should be considered. On the other hand there is little doubt that the lime companies could supply all the I lime needed provided that farmers spread their orders reasonably evenly throughout the year. If farmers gave more serious thought to this aspect of the problem a considerable amount of disappointment arising from delayed delivery would be avoided. LABOUR AND CAPITAL One difficulty that occurs as the result of a great rush of orders is the supply of sufficient railway trucks and covers; another is that lime companies suddenly need a number of extra men far casual work for a limited time arid they are not always procurable. Further, an increase in the size of a works and plant calls for a considerable outlay of capital; should a works function at full capacity for only a few months each year overhead charges may have the effect of maintaining production costs at a level that are uneconomical and unprofitable. It is well known that a plant running at somewhere near full capacity throughout the whole season can produce much more cheaply for each unit than one which has periodic slack periods. It is realized that from the farmer’s point of view top-dressing and liming operations carried out simultaneously with double-box machines are sound economic practice. Nevertheless, with some extra thought and good management it should be possible to spread orders for lime more evenly over a longer period. In this province, blessed with a reasonably even distribution of rain throughout the year, there is not much difference in the result from lime whether, it is applied in spring, summer, autumn or winter. Applications can usually be applied economically and effectively at any time of the year when the land is dry and at periods of some slackness in routine farm work.

Liming the land in Southland has long been recognized as an essential and profitable phase of farming operations. Men who succeeded in applying the correct quantity needed by each piece of land obtained the best results, especially in the form of high feeding value and fattening capacity in both pastures and fodder crops. This most desirable object was sometimes reached as the result of a certain amount of luck, but more often by careful experiment and observation over a long period. PRACTICAL SCIENCE In recent years effective and profitable liming has been reduced from the realm of guesswork to a practical science. This has been made possible by utilization of methods for ascertaining the reaction of soils by means of testing samples for the degree of acidity or alkalinity present. Whether a soil is acid, neutral, or alkaline has long been known to be one of the controlling factors in plant growth, but only since PH measurements have been applied to soils has it been possible to express this relationship in precise terms.

A good many farmers are now familiar with the term PH values, but are not very clear as to the exact meaning of them. This may not be a serious matter as agricultural instructors are available who have the necessary knowledge. However, a good many inquiries for more information on the subject have been received and the following may be of interest. Everyone is familar with the Fahrenheit thermometer. On this scale 32 degrees represents the freezing point of water. For the sake of illustration we shall assume that values above and below 32 degrees represent degrees of heat and coldness/respectively. Thus, any value higher than 32 degrees such as 34, 36 or 40 denotes an increase in heat, the degree of heat increasing as the numbers increase. On the other hand, any values below 32, such as 30, 28 or 20 denote an increase in cold-

ness, the degree of coldness increasing as the numbers decrease. In a similar manner the degree of acidity or alkalinity of a solution is expressed by the Hydrogen lon scale. Instead of being called degrees, as with the thermometer, the units on this scale are called PH. values. On the Hydrogen lon, or PH scale, a value of PH 7.0 represents neutrality. This means that if the material tested has a PH of 7.0 it is neither acid nor alkine. DEGREE OF ALKALINITY Following the illustration of the thermometer given above, any values higher than PH 7.0, such a 7.4, 8.0, or 10.0 denote alkalinity, the degree of alkalinity increasing as the numbers increase. Any values lower than PH 7.0, such as 6.8, 6.6, 5.0 or 4.0, denote acidity, the degree of acidity increasing as the numbers decrease. A PH value is therefore simply a number denoting the degree of acidity or alkalinity of a solution or soil. In order that a person may have some idea of the degree of acidity corresponding to various PH values, it may be stated that a soil solution which has a PH value of 5.0 is 10 times as acid as one with a PH value of 6.0. A solution of PH 4.0 is 10 times as acid as one of PH 5.0. Thus PH 4.0 indicates an acidity 100 times as great as PH 6.0. A similar relationship holds on the alkaline side of the scale. That is, a solution which has a PH of 9.0 is 10 times as alkaline as one which has a PH value of 8.0. In these days investigators of agricultural problems substitute PH values such as 4.0, 5.8, 7.4 or 9.2 for the indefinite terms “strongly” acid, or sour, “slightly” acid and alkaline.