76 Plant-life of the Oxford District 



stages of rough herbage and regressive scrub to tracts of small flowering-trees 

 which may give a pleasant appearance ; more commonly they are allowed to 

 remain as simple waste, harbouring all the weeds of cultivation and the hedge- 

 row, a mass of coarse grasses and larger herbaceous forms (Heracleum, 

 Paslinaca, Carduus crispus, Anthriscus, Ton'h's). Where the entire agricultural 

 country may appear as a garden, with beautifully clean arable fields under corn 

 and roots the hedges maintained trimmed to the level of the standing crops, 

 as the regulation plashed thorn-fence such roadside wastes present a striking 

 contrast, as the last remains of the indigenous flora, which seem strangely out 

 of place in a civilized country. 



Roads are again undergoing a system of reconstruction, and tar-macadam 

 solves the problem of dust in summer, as well as of mud in winter. 1 The 

 dusty roadside was a feature of the nineteenth century, and a relic from the 

 pre-railway coaching days. Motor-traffic soon requires a road broader even than 

 the old-time cattle-track : an optimum width for main lines of 700 ft. has been 

 suggested (France), 120 ft. in the London area. 



The Raihvay-line dates from 1844 (from Didcot) ; both the G.W.R. and 

 the L. & N.W.R. follow the alluvial flats north and south from Wolvercote, and 

 the former to Sandford and Radley, on a low embankment of ballast-gravel and 

 clinkers. This presents little botanical interest ; the banks being gay in early 

 summer with Senecio squalidus, Chrysanthemum Leiicanthemum, Lotus comic ul.itus, 

 later with Linaria vitlgaris, but apt to run dry in hot summer. The Wycombe 

 Line through Thame runs on a higher embankment to cross the Thames below 

 Iffley ; it cuts through the Corallian rocks and Calcareous Grit before Littlemore, 

 and by a deep cutting and tunnel through the Portland beds and Shotover sands 

 at Horspath. These embankments and cuttings exposing calcareous rocks 

 carry a varied and abundant flora. 2 



The main line down the alluvium, with several bridges over minor streams, 

 cuts the older flood-level into two tracts. That on the west is subject to floods 

 from the uncontrolled Hinksey Stream, 3 and the railway constitutes an effective 

 barrier to the exploration of the area. 



It may be noted that botanical interest centres in the fact that roads are 

 of very modern organization, and have little relation to the indigenous 

 flora. Where the track goes through woodland, it will show along its sides 

 all the characters of regressive woodland ; if through arable fields or pastures, 

 it will carry all the weeds of these formations, the more as it is less cared- 

 for. As traffic implies denuded ground, ' assisted ' vegetation will find a 

 station ; hence ' viatical ' plants are merely assisted indigenous forms, 

 mingled with assisted aliens whether brought by wind, or on the feet of 

 men and horses, the mud of cart-wheels, and the hair of animals. The dusty 

 roads of the nineteenth century, with exposure to sun and wind, favoured 

 desiccation, which implies a preponderance of xerophytes in dry summer. 

 Droppings of horses and cattle, adding manure to denuded areas, encouraged 

 the common weeds of waste places and human refuse, as also salt-storing 

 weeds and aliens. Modern usage of tarred roads and rubber tyres tends to 

 eliminate all plants whatsoever. It is interesting to note that in a modern 

 transitional phase, the Oxford district supplies admirable examples of modern 

 road, as also of all the older types that have been. 



1 Cumnor Hill was a mire in 1921 : Hinksey Hill was formerly so dusty in hot summer that one 

 could ride up it and not see others going down. 



* A slight sample of a regressive railway embankment, following disuse, is seen near Wolvercote 

 (Peartree Farm). The embankment approaches to the bridge over the river below Iffley were 

 reconstructed 1922. 



The Railway line was washed out in 1894, following which the line was raised somewhat, and 

 a series of 20 culverts made in the embankment to let the water through (Kennington Lane). 



