GROWTH OF THE SITKA SPRUCE AND OTHER TREES. 1 65 



not been completely consumed, and some oxidizable carbon still 

 remains to be burnt in the open air. The final result is that the 

 spent shale is burnt into a red, porous mass which becomes 

 slowly weathered, and crumbling down on the surface, will in 

 time make good enough soil for some kinds of trees, such as 

 larch, birch, and Scots fir suited for dry, porous land. The 

 drawback to afforestation on such places at present is the 

 quantity of dust and smoke in the air. But when, and if the 

 adjacent oil works were to stop, and the smoke cease, — an 

 event that will happen sooner or later — tree planting might 

 be attempted with prospects of good success. These ugly and 

 very prominent landmarks in the West Lothian landscape may 

 then hide their forbidding volcanic outlines under an attractive 

 mantle of arboreal greenery. 



We may now return from this little geological excursion to my 

 attempts at growing trees on the old colliery bings at Banton. 



Colliery debris containing fireclay breaks quickly down into 

 common clay, and if there is a mixture of sandstone and perhaps 

 engine ashes, the whole may produce suitable mixed soil for 

 trees or grass. But here the blaes contain, like oil-shale, some 

 bituminous matter, and so do not break down in such a way as, 

 with the help of grass, to produce much humus on which trees 

 can make a start. The black, loose materia], although devoid 

 of pyrites, has lain, in some instances, for more than a century 

 without accumulating much natural vegetation. It absorbs the 

 sun's rays, and becomes hot and dry in summer, so that the 

 tender plants have great difficulty in starting away at first. 



Many hundreds of larches, and some spruces and Scots firs 

 were planted on the blaes heaps in little pits, into each of which 

 a shovelful of good soil had been thrown. A few, particular'y 

 Larix leptolepis, have thriven, but most have failed to establish 

 themselves in the first two years. Sitka spruce is, of course, 

 not the tree for such a soil, and common Norway spruce has 

 proved quite a failure where tried. 



Some of the largest of the old bings have, however, been 

 removed for brick-making, and the waste land which they 

 occupied has been planted with more success. The area first 

 planted in 1904 extends to about 4 acres, and is situated about 

 350 feet above sea-level. The original land is here gravelly, 

 with some blaes and stones scattered about, and a little good 

 soil in places. Part rises into a dry knoll and part forms a wet 



