ROADSIDES AND HEDGES 



247 



luxuriant and less covered with dust, &c. 

 The frequent traffic with wagons, &c., causes 

 a good proportion of cornfield weeds to be 

 dispersed along the way. 



In the case of (3) and (4) the effect of traffic 

 is more or less negligible. 



Dispersal by Roads. As the media for traffic 

 of all kinds it is not to be wondered at that 

 roads afford one of the greatest means of 

 dispersal of plants. And though this is 

 obvious if one thinks about the matter at all, 

 yet it does not seem, like many other facts of 

 this nature to which attention is drawn in 

 these notes, to have been adequately con- 

 sidered. 



It should be noticed that the distribution is 

 in the first instance linear, but may be later 

 much more general, and the origin (via any 

 particular highway) may be obscured. Another 

 equally important fact is the extra protection 

 afforded by the unusual closeness of the 

 hedges, and the ample shelter they, and the 

 ditches, afford. The greensward also is 

 subject to interference from traffic by man or 

 horses, &c., or mowing in summer, or the 

 operations of the road-scraper, hedger, or 

 ditcher. 



Man himself is responsible for some dispersal 

 of seeds. Workmen carry in their bags plants 

 and soil, liable to be dropped in passing to and 

 fro. People using roads who have traversed 

 arable or even grass fields or woods are liable 

 to leave seeds behind embedded in mud from 

 boots or shoes, or which have been caught in 

 the clothing. Gardening operations in allot- 

 ments, &c., are responsible for a good deal 

 also, weeds being thrown over the hedge into 

 the road. 



Birds especially are liable to carry seeds 

 and drop them along the highway. Cattle, 

 horses, &c., disperse them in hoofs; and in 

 their coats, which are woolly or hairy, seeds 

 that are furnished with hooks or spines may 

 be caught, and so dispersed. The carting of 

 hay, corn, stones, lime, dressings, manure, 

 &c., is a very frequent source of dispersal 

 on highways. 



Wind is another factor. So also is the 

 drainage by ditches, water plants being intro- 

 duced in this manner. 



The Hedgerows in Fields and along the 

 Roadside. Since an integral part of the 

 highway is the hedgerow on each side, it 

 is best to regard the hedgerows in fields as 

 similar in character to the roadside hedge- 

 rows, for both have the same origin. One 

 feature of roadside hedges, however, is their 

 continuity in a more or less parallel course, 

 whilst hedgerows in fields are limited in 

 extent and direction to moderately-sized rect- 



angles ; so that dispersal along the wayside 

 is if anything more permanent. 



The roadside or border of each hedge on 

 a highway is frequently the habitat of a more 

 numerous ground flora, as it is less disturbed 

 in rural districts, but the hedge itself is usually 

 kept well trimmed and layered, whereas the 

 hedges in fields are often allowed to grow 

 for a long period untouched. 



Village Outskirts and their Influence on a 

 Roadside Flora. When a series of roads has 

 been studied and the floras of all compared, 

 one outstanding feature will become apparent. 

 It will be found as a rule, allowing for the 

 possible change in soil, altitude, moisture, 

 &c., that the flora of the roadside is fairly 

 uniform, when the immediate effect of villages 

 or towns upon the route is eliminated. 



But a noticeable fact, which will soon become 

 apparent, is the occurrence at variable distances 

 from a village of certain plants, which do not 

 travel far along the highway on either side 

 of a town or village. Such plants are, for 

 example, Greater Celandine, Winter Cress, 

 Dwarf Elder, Tea Plant, Hop, Horse-radish, 

 Chickweed, Comfrey, Borage, Alkanet, Clary, 

 Black Horehound, White Horehound, Pelli- 

 tory-of-the-Wall, Good King Henry, &c. 



Rarely, if ever, do these plants occur in the 

 majority of districts in any other or a possibly 

 native station. The probable reason of the 

 occurrence at all near villages or on the high- 

 ways, is the former use of these plants for 

 domestic or herbal or other purposes. They 

 cannot, in fact, be regarded as truly native. 



Gate-posts, Gateways, Bridges, Stone-heaps, 

 &c. The continuity of the greensward or the 

 hedgerow on a highway is sooner or later 

 broken by gateway, bridge, and stone-heap, 

 or some other equally welcome variation of 

 the general monotony. 



The gate-posts and gates on every highway 

 are a frequent source of interest to the lichen- 

 ologist. They afford also to the student of 

 flowering plants an easy means of wandering 

 for a while from the highway on either side, 

 and this makes the flora to be studied along a 

 highway more varied and interesting. 



About a gateway unusual plants will occur, 

 such as Wart Cress, Charlock (Raphanus), 

 Great Plantain, Knot Grass, various Cheno- 

 podia, Docks, &c., dispersed from arable or 

 similar open soil. 



Pearlwort may be found on the sides of 

 bridges, or Cerastium triviale, or Runie.v 

 Acetosella, and on a wet bridge over a road 

 I have seen growing amongst the bricks, 

 Epilobia, Scrophularia aquatica, &c. In the 

 water or on the margin, aquatic plants may be 

 found, such as Glyceria, Catabrosa, Lythrum, 



