74 PLANTING. 



the produce of the thinning: of a plantation, as well as in executing the 

 work in a careless manner, the same bad effects are not imfrequently 

 1 in young saplings. The decay which is observed at the lower 

 of the steins of larch trees, when planted on chalk, or on very damp 

 :iy the fault of tho subsoil, and sometimes appears when 

 the tree is only eighteen years old. In numerous instances we have 

 found it commence at the seventh year's annual layer of wood, and 

 ilier, and to extend to the thirty-fifth year's layer, but not beyond 

 that growth. In all our observations it appeared to be either within seven 

 ami thirty, or thirty and thirty-live years' layers. The fungus, which 

 appears in the defective wood, commences at the higher portion of the 

 main branch of the root connected with the annual layer atfected, and 

 proceeds upwards. Its characters are extremely similar to those, of the 

 rot (incruHus dt*tnn'tens)t so much so, that until more minute ob- 

 .tion determine to the contrary, they must be considered identical. It 

 i> highly probable, therefore, that the dry rot exists in the interior of 

 limber, while the tree is yet growing, although possibly in too inert a state 

 to be distinguished by the naked eye. In the living plant no remedy has 

 i'crn di-emered for this disease. Judicious planting will ensure pre- 

 tiOD by furnishing each distinct variety of soil and subsoil with 

 those species of forest-trees only which are best adapted to them ; and this 

 principle, whether in the herbaceous plants of husbandry, in fruit trees in 

 in timber trees in forest planting, is never violated with im- 

 punity. Various means have been tried, from time to time, to prevent the 

 appearance of dry rot in timber, as well as to arrest its progress when 

 un. The first of these objects is supposed to be gained by 

 _ the timber previously to using it. Some recommend the bark to 

 ff the tree to a certain height a year before it is felled, and the 

 -en tried long ago on the oak*, and more recently with the 

 larch. It would appear, however, in the latter case, that when the trees 

 \oung, the alburnum or sap wood becomes soft rather than hard under 

 the process. 



her mode of seasoning timber is by immersing the trees in water 

 a period of one or more years. This practice is considered very bcne- 

 , hut it is clear that the necessary proofs cannot be obtained under a 

 /(I of nra' umparative trials of seasoned and unseasoned wood 



in tin- tame building, and under the same circumstances in the building, 

 oiling of wood by subjecting it to a strong heat by means of 

 n tried, but, as in the former case, time is required to 

 dctermiii' i -y. When wood is left to the process of nature to be- 



^eaMined, tue desired effects are more perfectly produced by pro- 

 air the wood from rain and sun. Knowles, in his Essay on Dry Rot, 

 :uls tin- timber to be ' kept in air neither very dry nor very moist ; 

 ; it from the sun and rain by a roof raised sufficiently high 

 to |.iv\ent b\ this, and other means, a rapid rush of air.' Con- 

 air :nid a moM temperature encourage the propagation and growth 

 in a high decree. When unseasoned wood is 



he latent :in 'dr\ mi are thereby encouraged and assisted 



in . the fungus or alga- \\ith destructive 



'I t-r cutting down timber-lives is that in which the sap 



, midu inter and midsummer; but particularly the 



. three n;ik-trcfs, forty feit. in height, where they stood, and 

 LTiJ thi'y \\ere then cut down, and the results were 

 found to be in favour of the practice. 



