Rose Growing (1902) pp. 18-19
Walter Page Wright
FIG. 7.—STOCKS FOR ROSES—III. SEEDLING BRIER.
G, one year old plant of seedling Brier or Dog Rose (Rosa canina): x, the radicle or descending axis developed into a tap root; y, the lateral or side root; z, the collar or point of junction of the descending axis (root stem) and the ascending axis (stem above ground) where buds are forming which, unless removed, develop into strong growths; a, the central growth; b, the side growths or lateral shoots.
H, a two years old transplanted seedling Brier: c, the tap root transformed into a spreading root by being shortened to about 6 inches from the collar at the time of transplanting, and being bent to a nearly horizontal position; d, the side roots spread out semi-horizontally at planting, thus securing a fibrous development near the stem and surface of the ground; e, the collar or point from which buds (little reddish knobs) were cut off at planting; f, the top of the plant, which has extended and pushed side shoots; g, point of budding, always at the collar, it having been found by experience that the stock does not thicken equally when the junction of stock and scion is below ground.
I, two years old seedling Brier planted the previous autumn, when the seedling bed only one weak shoot and a straight down descending tap root with a few lateral or side fibres. In planting, a trench is taken out by line, and the plant placed against the bank, with the radical or tap root bent horizontally, hence the roots are all on one side: h, the root formation; i, the root stem; j, the collar; k, the central growth; l, the shoots which have sprung from the collar; m, the point of budding when below ground, to which practice some still adhere.
One of the characteristics of the seedling Brier is a vigorous root growth, as compared with top growth in the first, end even second year. A fibrous root formation is promoted by shortening the tap root at the time of transplanting the seedlings, which is done when they are a year old, or the first year after sowing; in the following season they are ready for working. The root system increases in vigour as the years roll by, and thus accords with the development of the head of the Rose. It is the stock par excellence for Teas and Hybrid Teas, and is also good for Hybrid Perpetuals, and is not nearly so prone to suckering as the cutting Brier and stock collected from the hedgerows.