Oils and Fats. 



496 



[June, 1912. 



Thus castor oil (seeds and husks) 

 remove about the same quantity of 

 nitrogen, distinctly more potash, but less 

 phosphoric acid from land than is re- 

 moved by a crop of wheat. 



But the really saleable portion of the 

 crop from the castor oil plants is the oil. 

 which like other true oils, contains only 

 carbon, hydrogen and oxygen, and is 

 free from nitrogen and mineral matter. 



Consequently the grower of castor oil 

 should restore to the soil the capsules or 

 husks and the "cake" left after the ex- 

 traction of the oil. Under these con- 

 ditions he would remove from the farm 

 nothing but what was produced from 

 the air and water, and his soil would be 

 unchanged in the amount of plant food 

 which it contained, except for the small 

 quantities of material locked up in t he 

 woody matter of the trees. 



Under these conditions, his soil should 

 not be impoverished by the production 

 of castor beans, but should on the 

 contrary become more and more fertile 

 since the plant food contained in it 

 should be gradually rendered more avail- 

 able to plants. 



Pruning.— All things being favourable 

 the young plants are likely to make 

 vigorous growth and some pruning will 

 be necesary to encourage them to assume 

 a spreading, bushy habit. 



Crops — In the fourth or filth month 

 after sowing the flowering begins, and 

 in the sixth the capsules are formed. 

 The picking is taken in hand in the 

 seventh month and terminates with the 

 ninth. 



Harvesting.— When ripe the capsules 

 become hard and brown, and spread 

 out somewhat on the stalk on which 

 they are borne. At this stage the spikes 

 should be removed from the plant by 

 cutting. This should be done rapidly as 

 soon as the capsules show signs of ripen- 

 ing, as if left too long on the plant they 

 are liable so dehisce and scatter the 

 seeds. When the collecting has once 

 commenced the whole crop should be 

 looked over about once a week. Owing 

 to the irregular ripening of the crop, 



the harvesting is a somewhat tedious 

 process, but as the work involved 

 is not laborious, it can be done 

 by women and children. In the United 

 States an endeavour has been made to 

 produce a type of plant which ripens the 

 capsules in any cluster at the same time- 

 The work of harvesting such plants is 

 considerably lessened, and there is a 

 smaller loss of seed. The collected cap- 

 sules should be placed in bags or in a 

 box-waggon, and conveyed from the 

 field to a drying shed. Where buildings 

 are not available for their reception, 

 a drying floor in the open may be easily 

 made by sweeping clean a piece of firm, 

 level ground, and enclosing it with 

 boards or sheet iron from 4 to 6 feet 

 high, to prevent the seeds being scat- 

 tered and lost when the capsules open. 

 Provision against rain must be made if 

 an open-air drying ground is used. The 

 capsules should be spread on the floor, 

 exposed to the sun and air, and occasion- 

 ally turned over. In less than a week 

 most of them will have opened and shed 

 their seed. The empty husks should 

 then be removed and the seeds swept 

 together and collected. The pieces and 

 husk and other debris with which they 

 are mixed should be removed by winnow- 

 ing, either by hand or by passing the 

 seeds through a fanning machine. In 

 some varieties the capsules do not readily 

 open, and it is then advisable to beat 

 them, or wooden rollers can be drawn 

 over them by a pony whose hoofs are 

 protected by being padded with flannel 

 or sacking. In some parts of India the 

 capsules are stacked in heaps in a build- 

 ing, and covered with straw and 

 weighted. After about a week the outer 

 husk is soft and rotten. They are then 

 exposed to the sun, and beaten to free 

 the seeds. Another process sometimes 

 adopted is to bury the capsules until the 

 outer husk has decayed and set free the 

 seed. The seed should be stored in a dry 

 place until sold or pressed for oil. 



In countries where the castor plant is 

 not systematically cultivated, but where 

 it grows wild or semi-cultivated, and 

 labour is cheap, the collection and pre- 

 paration of seeds on the lines indicated 



