250 



HINTS AND NOTES 



but some are elongated to reach the sun. 

 Those that grow on the hedgebank, such as 

 Hedge Mustard, are frequently much elon- 

 gated when on the northern aspect. Others, 

 as Herb Robert, have a straggly habit, as a 

 result of their growing forward to the light 

 through the hedge itself. 



Diversity of Types on the Roadside in Relation 

 to Perennation. The composite character of 

 the wayside flora renders it variable in respect 

 of the way in which the plants adapt them- 

 selves to the growing season, or acquire their 

 life duration or mode of perennation. 



The Elm, Ash, Oak, Lime, Poplar, Willows, 

 Hazel, Hornbeam, Sycamore, &c., all fre- 

 quently planted by the wayside, are deciduous 

 trees. Holly and Yew or Pine are evergreen. 

 The scrub or shrub type is similarly deciduous 

 e.g. Hawthorn, Cornel, Spindle, Buckthorn, 

 Apple, Field Maple, Rose, and the Bramble, 

 Spurge Laurel, &c., among undershrubs, are 

 all also deciduous. Box is evergreen, but is 

 only native on the chalk and oolite at Boxhill 

 and one or two other places. The aquatic 

 vegetation is largely herbaceous and perennial. 

 The sward is made up of herbaceous perennial 

 or annual Grasses, and some other perennials. 

 The bulk of the annuals, as Shepherd's Purse, 

 Wart Cress, &c., are derived from other sources, 

 cornfields, &c. 



Pollination of Roadside Plants. A particular 

 feature of the roadsides is the wandering of 

 insects along the roadside. They do not, as a 

 rule, fly away over the adjoining fields, but 

 continue their course along the highway. 



It is thus not surprising that the bulk of the 

 wayside plants are adapted to insect visits, 

 which are numerous, and that most of them 

 are cross-pollinated. But since nature has 

 allowed for the exigencies of the weather and 

 the occurrence of rainy periods, many of these 

 plants are equally adapted to self-pollination, 

 as Hedge Garlic, Greater Stitchwort, Perfor- 

 ate St. John's Wort, Herb Robert, Common 

 Bramble, Crab Apple, Hedge Parsley, Cornel, 

 Moschatel, and Elder and Cleavers are self- 

 pollinated, as a rule. In some the anthers are 

 mature first, as in the Teasel, Ground Ivy, 

 and Bugle, in others the stigma, as in the 

 Sloe, and Hawthorn, and Lords and Ladies. 

 The Ash, as well as the other hedgerow trees, 

 and the Nettle are largely pollinated by aid of 

 the wind. 



The Dispersal of Seeds of Roadside Plants. 

 The linear nature of a roadside, and its 

 boundary on either side by hedgerows, places 

 a certain restriction upon wayside plants so 

 far as the dispersal of seeds is concerned; and 

 it is therefore, in so far as the agency of the 

 wind is concerned, more or less definite in 



direction, either along the road or from one 

 side to the other. But it must be remembered 

 also that the field side of each hedge acts as a 

 barrier to the dispersal of seeds from the fields, 

 &c., from a distance, and there may thus be 

 an aggregation of seeds, stopped by such 

 barriers, along the highway. Moreover, the 

 very fact that a road is devoted to traffic, as 

 has been shown, ensures that seeds will be 

 dispersed by external artificial agency along 

 the way. The Clematis, Barren Strawberry, 

 Hemlock, Hogweed, Teasel, Nipplewort, Ash, 

 Nettle, have their seeds or fruits dispersed by 

 the wind. A large number of fruits are edible 

 or have hooked fruits, and are dispersed by 

 animals, e.g. Barberry, Sloe, Bramble, Rose, 

 Crab Apple, Hawthorn, Bryony, Hedge Pars- 

 ley, Cornel, Moschatel, Cleavers, Spurge 

 Laurel, Black Bryony, Cuckoo Pint. 



In other cases, such as Hedge Garlic, 

 Hedge Mustard, Greater Stitchwort, St. John's 

 Wort, Herb Robert, Trailing Vetch, Meadow 

 Vetchling, Great Bindweed, Red Bartsia, Wood 

 Basil, Ground Ivy, the plant has a mechanism 

 of its own for dispersing its seeds. 



Soil and the Roadside. The soil of the road- 

 side is liable to much alteration, not only from 

 the length and continuity of the road, and the 

 existence of cuttings which expose new layers, 

 but also on account of the interlacing character 

 of the roads. A road taken from S.W. to N.E. 

 on the east side of Birmingham would largely 

 pass over the same geological formation and 

 rock soil. 



A road such as the \Vatling Street, or Great 

 North Road, which cuts across these in a S.E. 

 to N.W. or S. to N. direction, however, passes 

 across a number of different formations. In 

 the west of England the rocks are all older, 

 and contribute to form siliceous soils. A few 

 plants need limestone or chalk, as Clematis or 

 Wood Basil. 



A large proportion grow on humus, as Bar- 

 berry, Greater Stitchwort, Herb Robert, Bry- 

 ony, Cornel; and some are equally at home on 

 either sand or clay, as Barbarea, Hedge Garlic, 

 Spindle Tree, Rose, Hogweed, Hedge Parsley, 

 Lords and Ladies. Sand without humus is 

 needed by Hedge Mustard, Trailing Vetch, 

 Bramble, Barren Strawberry, Hawthorn, Tea- 

 sel, Nipplewort, Great Bindweed, Nettle. 

 Clay or sand is the requirement of Barberry, 

 Crab Apple, Elder, Cleavers, Red Bartsia, 

 Ground Ivy, Black Bryony; and pure clay is 

 the soil for Moschatel and Bugle, as well as 

 the Ash, which grows in a native state best on 

 limestone. Each plant thus has a special pre- 

 dilection for some one type of soil. 



Methods of Survey. The vegetation of the 

 roadside is composite. There are zones of 



