THE VEGETATION OF WOODLANDS. 1 37 



primrose and the tufted male, lady and broad buckler ferns. 

 On lighter and drier loams, dog's mercury {AfetriiriaHs) and wood 

 sage (Teiicriiiin) indicate moderately deep soils with less humus. 

 The formation of raw humus is indicated by surface-rooting plants, 

 frequently by a mossy carpet which is easily stripped off. In 

 heathy woods, heather {Cal/una), the white wood bedstraw 

 {Gaiiitm saxalile) and the yellow tormentil {Potentilla erecta) are 

 abundant, while in grassy woods the tufts of wavy hair grass 

 {Aira flexuosa) and the loose creeping mats of soft grass {Holcus 

 mollis) are indicative. Blaeberry ( Vacciniiivi myrdllus), although 

 deep-rooted, generally follows a surface layer of humus. In the 

 case of recent plantations on ground previously non-wooded, a 

 layer of raw humus frequently forms as a result of open canopy, 

 especially on poor, dry soils or those constantly wet in winter ; 

 here again it results in a surface mat of moss and shallow-rooted 

 plants easily stripped off. 



Loss of mild humus may also result from the action of rain 

 and wind so that the humus, alternately wet and dry, is either 

 blown away or becomes decomposed. This change follows 

 frequent and heavy coppicing, and is often seen in the copses of 

 the drier parts of England. With the humus layer the woodland 

 plants are more or less exterminated, and the soil is left bare 

 and rain-washed or becomes covered with grasses and weeds 

 such as sheep's sorrel {Riimex acetosel/a), white bedstraw 

 {Galium), etc. The soil is so crusted that germinating acorns or 

 other seeds fail to establish themselves, except, perhaps, thorn, 

 sloe, whin, bramble and rose. In moister localities, the ground- 

 vegetation is generally heather, wavy hair grass, blaeberry and 

 other plants indicating the formation of surface raw humus. 



Assessment of Waste Land for Afforestatio.v. 



The methods for assessing the value of waste land have already 

 been carefully set forth by Mr A. C. Forbes.^ This paper rightly 

 lays most weight on the evidence obtained from trees already 

 growing on or adjacent to the area under consideration, but it is 

 recognised that this gives but a meagre amount of information. 

 Where trees are not present, the value of the area has to be 

 reckoned from other factors, those of locality, especially the " lie " 

 of the land and the kind of soil. To these, we think, ought to be 



^ A. C. Forbes, (a) Trans. Roy. Scot. Arbori. Soc, vol. xx. p. 142 ; {b) Report 

 on Forestry Work, 1904-6, Armstrong College, Newcastle, 1906. 



VOL. XXIV. PART IL K 



