This section is from "The Horticulturist, And Journal Of Rural Art And Rural Taste", by P. Barry, A. J. Downing, J. Jay Smith, Peter B. Mead, F. W. Woodward, Henry T. Williams. Also available from Amazon: Horticulturist and Journal of Rural Art and Rural Taste.
"In Prussia, Denmark, and the South of Sweden," says Mr. Westwood, "great care is taken of the trees in the public places, and in order to ensure the free action of the rain on the roots, the earth round the stem is kept exposed for about a yard; a circle of bricks or large boulder stones preventing the carriages or passengers from approaching the trees In the Dutch towns, however, where nearly every street has a canal running along the middle of it, another plan is adopted for defending the base of the trunks of the trees, rendered necessary by the limited space which can be afforded to them, and to the fact that the soil in these semi-aquatic towns allows the roots of the trees to find moisture sufficient, without any additional wet from the surface; for this purpose the lower part of the trunks of these trees is protected by a sloping pavement of brick-work, carried quite up to the bark, and about half a yard high, so that the trees rise, as it were, out of a cone of brick-work, "The care with which the trees iu the public places abroad are tended was also shown in the manner in which newly-planted young trees are supported.
Instead of being, as with us, left to themselves, or supported by two or three rough hedge-stakes, each is trained to straight, strong, cylindrical shafts of wood, fixed firmly upright in the ground, not only affording the trees support, but also allowing them to assume an ornamental and regular appearance at once".