44 



NA TURE 



[May 1 1, 1905 



three periods, one of growth, one of maturity, and lastly 

 one of decline and decay. Between the number of years 

 in each period a certain ratio is found to exist, and, taking 

 this as a basis, together with what is known of the tree 

 since 1700, Mr. Clayton arrives at the conclusion that its 

 age is not more than 500 years — certainly much nearer 

 the mark than the age of 1600 years assigned to it by 

 Prof. Burnett in 1842, who based his calculation on the 

 theory of the elder De CandoUe that a tree increases by 

 one-twelfth of an inch in diameter annually, an altogether 

 untrustworthy basis of calculation. 



There is quite a number of other interesting historical 

 trees dealt with in the article, for example, the Greendale 

 Oak in Welbeck Park, which belongs to the Duke of 

 Portland. Its height was recorded by John Evelyn in 

 1846 as 88 feet, while the altitude of the highest twig at 

 the present day is only 54 feet. In 1724 a roadway was 

 cut through the trunk, which girths 30 feet i inch at 

 4i feet from the ground. The height of the archway was 



sacred edifice, such as this yew and the Cowthorpe Oak, 

 and the association no doubt affords them protection. 



Another notable veteran is the great chestnut of Tort- 

 worth, Gloucester, which girths 49 feet 2 inches at 4 feet 

 from the ground. It also stands about 100 yards from a 

 very old and beautiful church. 



As regards the longevity of trees, the theory was pro- 

 mulgated at the beginning of the nineteenth century by 

 De CandoUe that the duration of life in trees was prac- 

 tically unlimited, neglecting accidents due to unfavourable 

 external conditions, such as the ravages of parasites, 

 injuries from storms, lightning, and other causes. Pass- 

 ing in review the vegetable kingdom, we find there are 

 some lowly organised plants, such as certain algEe and 

 fungi, the w'hole life cycle of which may be completed 

 within the short space of a few days, or even hours. 

 Among the higher plants we have annuals and biennials 

 the existence of which terminates with the production of 

 seed. Then we have the agave and certain palms, the 



then 10 feet 2 inches, but recent measurements show that 

 the highest point is now only 9 feet 3 inches, and the 

 lowest 8 feet b inches. This shows conclusively that a 

 subsidence of the trunk must have taken place within the 

 last 200 years, and, by assuming that a similar sinking 

 into the ground has occurred in the case of the Cowthorpe 

 Oak, Mr. Clayton explains the apparent discrepancies 

 between the earliest and latest recorded girth dimensions 

 of the veteran. The trunk being somewhat tapering, the 

 diameter naturally lessens as the sinking in proceeds. Mr. 

 Clayton adds a note on the testimony of a Cowthorpe man 

 named Oates, who said, " The tree has shrunk very much 

 in my time, and in shrinking the tree has twisted — the 

 Eastern branches towards the .South." 



Another notable tree as regards size and age is the 

 Crowhurst Yew, which girths 34 feet 4 inches on the 

 ground. It stands In the churchyard of that place. The 

 church must be very old, as it contains monuments of 

 Saxon and Norman workmanship. The author points out 

 that the oldest trees are usually in close proximity to a 



NO. 1854, VOL. 72] 



aerial portions of which may live from ten to forty years 

 until the production of flower and fruit terminates their 

 span of life, their place being taken by new aerial por- 

 tions developed from lateral buds at the base of the plant. 

 In the case of trees and woody shrubs, on the other hand, 

 new growing points are formed annually, but this vege- 

 tative process does not end in the production of flower and 

 fruit, so that, excluding accidents, there is no reason whv 

 that vegetative process should not be continued for an 

 unlimited time. 



The giant Wellingtonias of California are well known 

 examples of the age and dimensions which trees may 

 attain. A stem in the British Museum shows 1330 year- 

 rings with a diameter of about 15 feet. On the other 

 hand, certain Japanese dwarf trees are known to be of very 

 great antiquity, although lacking the size of the Welling- 

 tonias. \\. the same time, one must not lose sight of the 

 fact that the living cells are continually being renewed, and 

 that in a tree like the Cowthorpe Oak the living parts 

 are at most but a few vears old. 



