896 



JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Garden soil is often considerably altered and ameliorated to suit the 

 plants grown ; so it is more upon the deeper-rooting trees and wild plants 

 or weeds that the influence of the surface geology is most noticeable, as is 

 shown in Table II. 



Before considering in detail the various strata of rock I propose 

 mentioning some of the plants characteristic of the commoner kinds 

 of soil, grouped into the wider classification of plants of sandy soils 

 clay, lime, and peaty soils, and those which grow close to the seashore. 

 For this purpose I quote liberally, with Mr. A. D. Hall's permission, 

 from his book on " The Soil." 



Plants showing preference to certain Soils. — Mr. Hall tells us that 

 the common primrose is undoubtedly a clay lover, yet it will be found 

 widely distributed over all the English soils ; the beech and the yew 

 are typical trees of the chalk ; good oak and hornbeam of the clay ; 

 Spanish chestnut and many conifers, like Scotch fir, are sand lovers ; 

 yet each of these trees will be found commonly enough on other kinds of 

 soil, though generally thriving best on the soils named. 



Most of the leguminous plants like lime, but there are others 

 that are intolerant of lime in the soil, such are lupines, seradella, and 

 gorse ; whilst of grasses, the sweet vernal grass is said to be intolerant 

 of chalk. 



Plants of Sanely Soils. — Among plants specially suited to sandy soils 

 may be mentioned potatos, which require liberal manuring, including 

 potash ; carrots thrive especially well on sandy land with a deep, fine 

 tilth. In Prussia lupines are used in reclaiming sandy land. The 

 Spanish chestnut, birch, holly, and many conifers thrive on sandy land. 

 Pinus Pinaster and Spanish chestnut dislike lime. Heather, rhodo- 

 dendron, and azalea are intolerant of lime and are associated with 

 sandy and peaty soils. Gorse, broom, tufted vetch (Vicia Cracca), and 

 bird's foot (Omithopus) are characteristic leguminous plants of sandy 

 land. Cranberry, bilberry, foxglove, sheep's sorrel (Bumex Acetosella), 

 bracken (Pteris aquilina), wavy hair grass (Aim flexuosa), spurrey 

 (Spcrgida arvensis), corn marigold (Chrysanthemum segetum), long 

 smooth-headed poppy (Papaver dubium), and blue cornflower (Centaurca 

 Cyanus) are characteristic plants of sandy soils. 



Plants characteristic of Clay. — On some clays of close texture the 

 grass is poor and surface rooting. Stoloniferous grasses, like marsh bent 

 grass (Agrostis stolonifcra) prevail ; on the poorer pastures the spiny 

 form of rest-harrow (Ononis arvensis) grows, along with wild teazel 

 (Dipsacus sylvestris), corn crowfoot (Ranunculus arvensis), dyer's green- 

 weed (Genista tinctoria), all characteristic and often troublesome 

 weeds ; on cultivated land the black-bent or slender foxtail [Alopecurus 

 a <j rest is) and corn mint (Mentha arvensis) are difficult to deal with. 

 Many clays are deficient in phosphoric acid, though containing sufficient 

 potash, and are benefited by the application of basic slag or super- 

 phosphate. 



Plants characteristic of Calcareous Soils. — Calcareous soils are gene- 

 rally warm and dry, and when deep, extremely fertile. The thinner soils 

 are rather subject to certain insect pests, like turnip flea. Calcareous soils, 

 many of them, need vegetable matter and are greatly benefited by farm- 



