The Ascent of Water in Trees (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1905 Excerpt: ...the direct physical consequence of the lesser resistance to flow in the vessels more completely filled with water. The fact that the water disappears first from the largest vessels led Strasburger to conclude that these are more used for storage than conduction, but here again we have a direct physical consequence of the more 'Bot. Gaz., ' vol. 34, p. 161. t Jamin, 'Compt. Rend., ' 1860, vol. 50, p. 385. I 'Rau und Verricht., ' p. 800. 'Proc. Roy. Dublin Soc., ' 1903, vol. 10, p. 48. 'Sitzungb. d. Akad. d. Wiss. zu Berlin, ' vol. 34, 1886, p. 561. ready flow through the larger vessels. The conclusion that if all the vessels in the intact plant were filled with air, no re-establishment of conduction is possible, is incorrect, as will be shown by the experiments on the Maple, detailed later. Dry dead stems cut and injected with water have their conductivity restored temporarily at least, so long as the vessels are open, and the root-pressure may act in the same way in an intact plant. After transplanting, however, the absorption by the roots may be insufficient to make good the loss by the leaves, etc., in which case a rapidly increasing block is created, which may ultimately prevent any re-establishment of the upward flow. In such cases, injection with water under pressure through a side branch should give the tree another chance of recovery, which practice is worthy of experimental trial in the transplantation of slowly rooting trees under dry conditions. The whole structure of the wood is such as to allow of the existence of channels filled with water alongside others filled with air, and water is also able to pass air-bubbles in the vessels while the bubbles remain stationary owing to their adhesion at one or more parts to the internal thickenings. It i