Agriculture and Soils op the Cape Province. 827 



A few words concerning^ crops that are not grown at Witkop, but 

 which would probably do vrell. will not be out of place, especially if 

 they are crox>s that will help the farmer to carry more stock and 

 plough more acres. Of such crops mangel wurzel, swede turnips, 

 and white turnips should do very well. Mustard should also succeed 

 as a seed crop. Clovers, sainfoin, vetches, rye grass, and teff grass are 

 likely to succeed as hay crops and soil improvers. Horse beans and 

 field peas are crops that sliould do well and provide not only an 

 increased store of fodder, but also a source of income from sales. 



The climatic conditions would appear to be very suitable for the 

 apple and the pear, for ordinary and for greengage plums. Of 

 smaller cultures blackberries, raspberries, currants, gooseberries, and 

 strawberries are among those that might be expected to thrive at 

 Witkop. 



In conclusion, I have to thank members of my staff (particularly 

 Mr. W, Torrance, who made most of the analytical determinations) 

 for the assistance they rendered in connection Avith the above work. 



APPENDIX 



Methods of Analysis, etc. 



1. Samplivg. — This was done in accordance with the official 

 instructions of the Department of Agriculture (vide Regulations and 

 Tariff for Chemical Analyses of Agricultural Materials). 



2. Chemical AnaljisiK. — (a) Nitrogen by Kjeldahl's method; (h) 

 lime, magnesia, phosphoric oxide, potash, and insoluble inorganic 

 matter were determined, after extraction of the soil, for twenty-four 

 hours in a boiling water bath, with hydrochloric acid, sp.g-. 1.112; 

 (c) "available" potash and phosphoric oxide were determined after 

 extraction of the soil according to D\pr's method. 



3. Mechanical Aiialysis. — -A. D. Hall's beaker method was 

 employed. 



N.B. — (1) Humus in the analysis represents the loss on ig*nition 

 of the clay fraction. (2) Carbonates were determined by the method of 

 Hutchinson and Maclennan (/. Afjr. Set., 1914, p. o23). 



4. Permeability to Water. — 100 grns. of air-dried fine earth are 

 made slightly moist and then packed into a brass cylinder having a 

 00-mesh gauze bottom, and provided with a detacliable snugly fitting 

 funnel. The height of the cylinder is 4^ inches and its diameter 

 Ih inches. The soil having been packed into the cylinder, it is covered 

 with a circular piece of filter paper. Distilled water is then added in 

 definite quantity and the cylinder covered. 



After the water has commenced to percolate well, water is added 

 to restore the original head above the soil column and the time noted. 

 Percolation is allowed to proceed until about 40 c.c. have been 

 collected and the time again noted. A graduated cylinder is used to 

 collect the percolate. 



Finally the rate of percolation is calculated, i.e. c.c. water per- 

 colated per sc|. cm. soil surface ])er houi', 



