58 Plant- life of the Oxford District 



arises, and the plots require a certain amount of attention in early stages. 

 Hence in the cultivation of such a form, seedlings have to be raised in a nursery, 

 planted out in an early stage of growth, and the rapidly growing weeds and 

 intrusives kept down by methods of cleaning. 



In general practice young plants from the nursery are planted at 4 ft. 

 apart each way, to grow to uniform pole-height, before thickening the main 

 trunk ; and by making close-canopy these may effectually dominate the ground- 

 flora in the course of a few years. Full dominance is only gained in 10 years 

 or so. In the first years after planting, the ground-flora may be more con- 

 spicuous than the crop ; the spaces regenerating Bracken, Brambles, and a large 

 supply of intrusive grasses, unless these are periodically cleaned and cut out. 

 All such cleaning and early thinnings add to the expense of production ; and 

 the age of the crop for felling, simultaneously as a crop, has to be adjusted by 

 financial considerations in order to make it pay. A continuous output is 

 maintained by a succession of plantings, involving successively maturing tracts 

 of such woodland. 



As local examples of such methods may be distinguished : 



(1) Clearing of Oak coppice? allowing free light-supply to the ground-flora, 

 but with effects of increased desiccation owing to the loss of the damp canopy. 

 Xeromorphic forms become more conspicuous, with a wide range of intrusives 

 from dry situations, giving a greatly increased variety of species (60-100); 

 Kennington underwoods, Oak-stools at 3 yards apart. 



With the growth of the coppice- regeneration after 4-5 years, these in turn 

 dwindle, shade-plants become more numerous, and in 8-9 years the effect of 

 a shaded woodland, largely restricted to spring flowers, is again produced. 



(2) Clearings of more modern forest-practice, involving clear- felling of older 

 woodland, and replanting with a crop of deciduous Larch, either pure or 

 subsequently underplanted with Abies or Beech; the trees being planted at 

 4 ft. From the examination of plots of different ages, it is possible to visualize 

 at one time the successive stages of succession ; and the general effect as 

 the control of the ground-flora expresses the success of the working-plan. 

 (Sunningwell Bottom, Milestone Piece, Bagley Wood.) 



Good examples are afforded by the experimental plots of the Forestry 

 School at Bagley Wood. Such plots are however subject to periodic cleaning, 

 with removal of the larger intrusive shrubs, bracken and brambles, as also the 

 thinning of the main crop and removal of dead laterals. 



Cases of special interest, followed in such forest-plots, are observed as the 

 main crop involves a tree-form which may be evergreen, or distinctly alien, 

 or no longer indigenous, and its relation to the general ground-flora. Such 

 plots include Pinus sylvestris, Pinus Strobus, P. Laricio, under which, when 

 planted at 4 ft., the canopy is so dense, and the ground so covered with a 

 carpet of needles (2-3 in. deep), that nothing whatever grows, as soon as the 

 canopy is attained. The same applies to Pseudotsuga and Thuya plicata with 

 still darker canopy : in the last case, with deepest shade, the floor is a dense 

 carpet of dead phyllomorphs, through which not even a residual Scilla pierces. 

 Pfnus-cznopy opens out after 20-25 years. 



Under Larch, however (European, Siberian, Japanese), owing to lighter 

 canopy in summer, and the deciduous habit, the undergrowth at first may fill up 

 with Bracken, which when left uncut, 2 is the agent more particularly concerned 

 in keeping down all lower ground-flora. Brambles may long continue ; but the 

 carpet of needles is at length only varied by a few stray plants of Ajuga, 

 Teucrium, Scilla, etc. (20 years). On thinning, and growth to higher canopy, 

 at 30 years Larch-plantations may again give Bracken undergrowth as light 

 penetrates, and should be under-planted. 3 The crop matures at 60 years 

 or more. 



1 Schlich, loc. cit., p. 341. 



2 Owing to want of labour during the years of the war, many of these tracts were much neglected, 

 and are not to be taken as fair samples of sylvicultural treatment. 



8 Schlich, loc. cit., p. 404. 



