t 555 ] 



extraction of sugar from beet or sugar-cane, are rich in K 2 0. 

 Crude gur contains a great deal of KNOs and the refuse 

 of sugar factories is therefore rich in potash, Wood-ashes 

 contain 5 to 7 per cent, of K- 2 O ; straw-ashes less. Wool 

 and hair are particularly rich in K2O. Ashes obtained from 

 all tender and green parts of plants are, as a rule, rich in 

 potash, e. g. t ashes of sun-flower stalks, of plantain and other 

 tender leaves, of maize-stalks, of sugar-cane refuse, of tobacco 

 leaves and midribs, &c. All such ashes or substances should 

 be carefully stored in the manure-pit. Potash manures are 

 particularly helpful to the growth of leguminous crops, 

 leafy crops, root crops e. g., yams, 61, kachu, potatoes, gram, 

 groundnuts, cabbages &c. Silt, especially fine dark coloured 

 silt, brings so much of potash in an available state that no 

 potash-manure need be applied to any land which is occa- 

 sionally renovated with silt. Irrigation water also brings 

 sufficient potash, as it contains about 10 to 20 parts of 

 K.,0 in a million parts. Rain water, of course, contains no 

 K 3 O. Potassium nitrate and cattle urine are the best potash 

 manures ordinarily available. The urine of poorly-fed cattle 

 is richer in potash than the urine of well-fed cattle, because 

 the former feed principally on grass and straw which con* 

 tains a larger proportion of potash than better food materials. 

 909. Compost. In making compost it is better to use 

 ashes than lime and salt. The object of using an alkaline 

 substances as manure is to hasten its decomposition. As 

 potash is in itself a more valuable food substance than lime 

 or soda, ashes containing some lime and soda in addition 

 to potash are to be preferred. The power of potashes to 

 make the N of the soil available for plants is also well known 

 and the application of potash manures is therefore of great, 

 indirect value. Ashes also increase the capillarity of the soil 

 and Lorain observed that the ground where logheaps had 

 been burned was moister than the surrounding soil. Indeed 

 excess of alkali is often outwardly recognizable by the puddly 



