I.NQUIKIKS AiNJJ UePLIES. 18? 



Winter Ploughing. 



yr/rt/i-W'est Urrnif/c Frcr Sfnfe. — Whnt ad\antnff(" is thfie in 

 wintei' ploug-lnng'? 



five Frinclpal, Glen School of Agriculture, replies : There is not 

 one advantage, hat many. TTsually on South African farms where 

 maize is grown to any extent the area under this crop is limited by 

 the amount of' land which can be ploughed and planted after the 

 spring rains. If the land is ploughed in the winter much of it need 

 only be disked or harrowed prior to planting, and consequently it will 

 be possible to get a much larger area planted at the proper time. Not 

 only does winter ploughing- make an extension of area possible, but it 

 also improves the yield. Moisture is the commonest limiting factor 

 in crop production in South Africa, and any method which will 

 increase the water supply to the plant should be adopted. Ploughing 

 the land in the spring after the rains brings about great loss of 

 moisture badly needed, it being common knowledge that freshly 

 l)Iouglied land dries more rapidly than laud undisturl)ed or distuilted 

 to a dejith of one or two inches only. Moreo\er, winter i)b)ugl)ing 

 serves to increase the proportion of rainfall absorbed and to k^sen Hie 

 run off. Exi)erience also shows that winter ploughing serves to 

 lessen the attacks of various insect pests, particularly stalk-borer. 

 Finally, the turning over of the land in \vi)iter has a beneficial effect 

 on the biological condition of the soil, and should also assist in render- 

 ing available plant food in the soil. 



^Vhatever the argument and theory may be, the fact remains thai 

 winter i)loughinQ> increases the crop yield, and is now being practised 

 by the most successful and progressive farmers all over the country. 



Read the article appearing in the jNIay, 1922, number of the 

 Journal on " Causes of High Cost of Production of ^Faize and tbe 

 liemedv" 



Potato Fertilizei'. 



Betlial. — Last year 1 made up for my potatoes a mixture to the 

 ton — 1000 lb. superphosphate, 400 lb. bone, 400 lb. guano, and 

 200 lb. potash. The soil was of a sandy loam type, the crop answering 

 very badly. In my opinion the mixture was not in the right i)ropor- 

 tion. I am sending two soil samples from this land for analysis, and 

 1 want you to tell me what is necessary and how the mixtures could 

 Imve been lietler balanced. Maize following the potato crop for two 

 years yields about fifteen bags per acre. This cro]> is not fertilized. 



TJie Principal, School of Agriculture, Fotchefstrooin, replies: 

 Your potato fertilizer is quite well proportioned, but you do not 

 mention at what rate you applied it; 400 lb. per acre would be 

 sufficient. I do not think that soil analysis will help your case in 

 the slightest. You have supplied everything the potato requires 

 except organic matter. If you add two to four tons of mantire in 

 addition, I think you will notice a big difference. The low yield uiay 

 als<^ have been due to disease or insufficiencv of moisture. 



