Note 23 — PART II. BRITISH FOREST TREES USED AS NAVAL TIMBER.

The landlord agriculturist is sufficiently aware of the influence of the baring the upper part of the root of turnip, while the plant is young, in extending the future growth of the bulb, and that a dry situation gives most root in proportion to stem. These are general laws in vegetation. There are few observers who have not remarked the very large size which roots have attained when the trees have originally been planted on dikes, and the dike earth removed, leaving the roots bare. Should any person examine the very great difference of thickness between the upper and lower part, from the heart of a root near the bulb, he will at once discover the influence of exposure to the air and freeness from pressure in promoting the swelling.