The Growing of Mine Props on the High Veld. 265 



In exceptionally favourable conditious tlie planting espacenient 

 may be made wide]', 9 feet by 9 feet being- tlie limit (538 trees to the 

 acre). In this case only a little thinning will be needed towards tlie 

 latter part of the rotation. But, as a rule, this plan is not recom- 

 mended, as it involves much more cultivation and incurs the risk of 

 introducing quick grass, which may be fatal to the crop. In the 

 wider espacement greater thickness is attained in the lower part of 

 the bole in a short time, but, on the other hand, this tends to a more 

 pronounced taper. Though prop sizes are thus secured somewhat 

 earlier in the bottom lengths, there is more waste in the upper part, 

 and the percentage of props in the final stand will be smaller than 

 iii a stand that lias been kept normal from the start. If, on the other 

 hand, telling in a widely espaced stand is delayed until the upper 

 part of the stem is more developed, the lower part will become too 

 thick for props. 



The wood is of an inferior quality, and is unsuitable for 

 industrial purposes even when mature. Its present commercial 

 value is entirely due to tbe present scarcity of timber, serving Avell 

 enough for temporary purposes where nothing better can be got. 

 It is planted on a large scale, almost exclusively by private enter- 

 prise, especially in the vicinity of the mines. How long the demand 

 for this class of timber will be maintained it is impossible to say, 

 but should the supply of props at any time exceed the demand, the 

 market for Eucalyptus viminalis timber will become restricted, and 

 will disappear entirely when sufficient better class timber is available. 



Eucalyptus rostrata. 



This timber is strong and durable when mature, and is therefore 

 useful for any industrial purposes where such (jualities are needed. 

 A good depth of soil, say, G feet or more, is required for it to attain 

 large saw-log dimensions, but less depth will suffice for props, say, 

 down to 3 feet. It needs sub-soil moisture, and does not object to 

 brak or to inundation in a fairly mild climate, but is less frost-hardy 

 than Euc. vit/ilnalis during the first few seasons, and must therefor 

 be kept out of low-lying situations on the high Aeld. Once well 

 established it will withstand any cold experienced in these parts, 

 and does not suffer from drought if the stand, is kept sufficiently 

 dense to exclude quick grass. The crown is usually light, and in 

 an open stand its natural liabit is branchy and crooked, hence close 

 planting and early thinning is necessary to produce straight stems. 

 A planting espacement of 4 feet by 4 feet (2722 to the acre)is there- 

 fore recommended as the safest, especially in weedy lands. In good 

 clean ground, 6 feet or more in depth, 5 feet by 5 feet (1742 to the 

 acre) may suffice. It is a fairly fast grower, but takes about five 

 years longer than Euc. ciininalis to attain prop sizes. On the other 

 hand it is a safer permanent crop in case the demand for props 

 should decline. 



Eucalyptus Maidenii. 



This tree is of comparatively recent introduction, the oldest 

 stands in the Transvaal being about thirteen years. But sufficient 

 experience has been gathered to justify advantage being taken of 

 its many good qualities, provided great care is exercised in selecting 

 the right situation. It is a handsome tree with a foliage difficult to 



