148 TRANSACTIONS OF ROYAL SCOTITSH ARBORICULTURAL SOCIETY. 



The question naturally arises, how can the primary disease be 

 prevented, and what steps have to be taken when the crop has 

 been attacked ? Prevention is certainly easier than cure, and, to 

 judge from the investigations so far as they have gone, it would 

 seem to be sufficiently safe to cultivate Scots pine or any other 

 conifer on farm or waste lands, after establishing forest-soil con- 

 ditions by a preliminary crop of some soil-improving species. 

 Even a liberal admixture of such species, Acacia in preference, 

 with an original pine crop would probably suffice to prevent any 

 root disease. When the young growth has been attacked, the 

 stems that lag most behind in height-growth, especially those 

 which have sent out no new shoots at all, should at once be 

 removed, and replaced by some fast growing soil-improving 

 species. To sit and await results means merely waste of time, 

 and is courting further disaster. 



We have no absolute proof that the spread of Folyporus when 

 it has once established itself in a diseased afforestation area can 

 be controlled, but experiments with isolating ditches made over 

 an area of over 2000 acres, by Herr von Klitzing, Charlottenhof, 

 have so far had the desired result. This the owner of the 

 forest ascribes to the early application of the measure, for as 

 soon as a young stem was seen to be in a dying condition, it 

 was at once surrounded with a circular ditch of 30 feet diameter. 

 These forests have not yet passed the critical age, but favourable 

 reports regarding the efficacy of the measure are also received 

 from France, and any forest owner would be rash not to try 

 isolation. 



In India, the field of my former labours, most of the pines, 

 especially Pinus excelsa, but also Piniis lo?igtfolta, which is 

 certainly no soil - improver, take fairly rapid possession of 

 deserted fields, but still this is a gradual process, in which bushes 

 of all sorts probably play a considerable role. Only once, in 

 1871, did I try my hand on sowing some old fields with Finns 

 longifoHa. The first results were excellent, but when I returned 

 in 1883 no vestige of my attempt was left. 



