WASTE PLACES 



251 



Marsh Bedstraw, Hemp Agrimony, Fleabane, 

 Coltsfoot, Butterbur, Water Ragwort, Marsh 

 Thistle, Yellow Loosestrife, Creeping Jenny, 

 Scorpion Grass, Water Betony, Musk, Mint, 

 Gipsyvvort, Skullcap, Amphibious Knotgrass, 

 Crack Willow, Yellow Flag, Fritillary Rush, 

 Reed, require either sand, clay, or peat. 



Methods of Survey. The particular form of 

 aquatic vegetation will at once determine the 

 mode of survey. In a pond or lake the vege- 

 tation is generally concentric, hence the map- 

 ping must be done on such lines ; whilst in a 

 river, stream, or ditch it forms more or less 

 parallel bands or zones, and should be done by 

 making cross-sections (as indeed may be done 

 in the first case). 



The division of aquatic vegetation into zones 

 of floating, submerged, and reed-swamp asso- 

 ciations renders it necessary to study them by 

 these zones. Any one may be studied by itself, 



or all the zones together. In either case the 

 dominance of any particular plant should be 

 noted. 



Such points as the character of the mineral 

 salts in the water should be studied by ad- 

 vanced students. 



The rate or character of the current should 

 be noticed. The juxtaposition of the different 

 societies should be noted at different points. 

 In the case of wet places they may be studied 

 in the same way as meadows and pastures, 

 and the tape or stakes may be used for mark- 

 ing out squares to be studied one by one in 

 detail. 



The zones that lie deepest in the water can 

 only be studied by aid of a boat, and this may 

 be a difficulty not easily overcome. The 

 dredge may be used to examine not only 

 the lowest zones of flowering plants but also 

 the plankton, which occurs at the surface. 



SECTION IX 



WASTE PLACES 



Artificial or Natural Character of Waste 

 Places. The term waste ground or waste 

 places is capable of more than one meaning. 

 There are comparatively natural types of 

 waste land, which, although following the 

 destruction of forest lands originally, may 

 be in their present stage untouched by 

 man. But these types are hardly, if at all, 

 represented in this country; and to all intents 

 and purposes waste places denote pieces of 

 ground that are associated with cultivation. 



Open Character of the Ground. The waste 

 places, as implied by the Latin names of many 

 of the plants that are found there e.g. 

 arvensis, found on ploughed land ; agrestis, 

 cultivated land ; sativus, segetum, sown are 

 characterized by their association with the 

 plough or the harrow, &c. Watson called 

 plants of cultivated ground agrestal, includ- 

 ing Papaver, Agrostemma, Bromus secalinus, 

 Veronica agrestis ; but these are more especially 

 cornfield weeds. They share the same charac- 

 ter, however, in growing upon open ground 

 that is liable to be broken up and disturbed, 

 and from which close-growing, spreading, 

 and tenacious types, such as Grasses and 

 other meadow plants, are continually being 

 ousted. 



The plants thus have to compete with less 

 severe conditions, and their struggle for 



existence is far less arduous. Waste ground 

 possesses the same character, being open and 

 frequently new ground, upon which may 

 appear in their proper rotation alga. 1 , mosses, 

 and flowering plants, or the latter may pre- 

 dominate. 



It is natural that the relative openness of 

 such stations may differ considerably, for if 

 once allowed to return to a more natural 

 and permanent condition the alien types 

 disappear, and Grasses, &c., take their place; 

 and the persistence of particular types in spite 

 of this is a mere matter of adaptiveness, which 

 some plants possess in a remarkable degree. 



Chersophytes. The name Chersophytes is 

 given to plants that grow in regions where 

 there is a sufficiently moist climate to admit 

 the existence of forest land or scrub, and on 

 which, after this has been destroyed on dry 

 soils, perennial dry-soil types may grow. 

 They, however, are not steppe plants, though 

 they may resemble them. In the eastern 

 counties, which like the rest of the country 

 were subjected to steppe conditions following 

 glacial conditions, certain plants that may be 

 regarded as steppe plants occur. And strpjM- 

 conditions an- akin to desert conditions, which 

 are similar in the character of the habitat to 

 sand-dune formations, widely represented 

 along the British coasts, both types of 



