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.
At the last meeting of the London Pomological Society, Mr. Rivers, of Saw-bridgeworth, exhibited three pyramidal Pear-trees, and with them the following memoranda. He said: " The trees (Louise Bonne of Jersey) are from seven to eight years old. No. 1, a tree budded on the Quince, has struck root from the collar of the graft; as soon as this took place, about three or four years ago, all the Quince roots died, for, as will be seen, the stump is quite bare. These (Pear) roots penetrated into the solid, calcareous clay to the depth of nearly five feet, and so hard was the clay that the spade could not penetrate it so as to take them out to their full length. As soon as these roots struck into the clay the tree ceased to bear, and its shoots became full of cankery spots, the leaves more green than those on the Quince roots, and the young shoots more vigorous, although they cankered and died back. Out of a plantation of two thousand pyramids of this variety on the Quince, only the tree now sent and another have struck root from the collar of the graft, and both are in the same state. Last year, every tree except these two was covered with the very finest fruit; the tree sent did not bear one - the other produced two or three, which were cracked, spotted, and worthless.
No. 2 is a tree of the same sort, on the Quince stock, which grew within five feet of No. 1; this, in common with the others in the same plantation, has no canker, and has borne fine, clean fruit. The soil is moist, and brings on moss to a small extent. No. 3 is on the Quince, and is a young tree that has been twice removed. Trees of this kind, where soil is not favorable (and I have a part of my nursery the soil of which is very wet and cold), I remove biennially, giving them a compost of sand and rotten manure. In a few years, their roots become like those of rhododendrons, and keep close to the surface, so that the trees keep in good health, and bear profusely. The fibrosity of the roots of the tree sent is remarkable".
These specimens were extremely interesting, showing as they did that the Quince was better suited for certain kinds of soils than the Pear stock; they also showed how necessary it is to keep the roots of our fruit-trees near the surface, and indicated that, under certain circumstances, at least, to deep rooting we owe barrenness and canker. - Ibid.