Years. 



Palms of. 200, 300 



300 

 327 

 3o5 

 383 

 443 

 516 



Cercis, 



Clieroilfiutroii, 



Ulmus (Elm) 



Cupressus (Cypress) . 



Hedera (Ivy) 



Acer (Maple) ....... 



ON THE AGE OF TREES. 



Years. 



Cnstanea (Chestnut) 300, 626 



Citrus (Lemon, Orange, 



&c.,) 400,509,640 



Plalanus (Plane) 720 



Ccdrus (Cedar) 200, 800 



Juglans (Walnut) 900 



Tilia (Lime) 304, 530, 800, S25, 1036 

 Abies (Spruce) 1200 



Years 

 Quercus (Oak) 600, 800, 8G0, 1000 

 ICOO 



O'.ea (Olive) 700, 1000, 2000 



Taxus (Yew) 1214, 1466, 2588, 28S0 

 Schubertia (Taxodium). . 3000, 4000 



Leguminosrea 2052, 4104 



Adansonia (Baobab) 6000 



Draca;na (Dragon Tree) 6000 



Larix (Larch) 203, 570 



"We might add considerably to tliis list, but it already supplies a sufBcient number of 

 illustrations of our general remarks. 



The means, by which the age of these trees has been ascertained, are two — first, from 

 historical data, and second, from counting the zones. Thus, the colossal Dragon-tree of 

 Oratava is known to have existed, in almost its j^resent condition, in 1402; and comparing 

 it with the younger trees in its neighborhood, its vast age is inferred. The Yew trees at 

 Fountain's Abbey, in Yorkshire, are known to have sheltered the monks whilst the abbey 

 was building. The abbey is now in ruins, but the trees retain their vigor; the lowest age 

 that can be assigned them is twelve centuries; they are probably much more. But where 

 trees have been cut down, the method of counting the zones has been had recourse to. 

 There is no difficulty in this where the tree is sound; but in many instances, the older 

 trees are, the more likely they are to be decayed in their center. The plan then adopted 

 is, to take a square inch, count the zones in it, multiply this number by the number of 

 inches from the bark to the pith, which will then give the whole number of zones, and the 

 age of the tree. This Avas the plan adopted by Adanson in calculating the age of the 

 Baobabs of Africa, and which has also been employed in calculating the age of other 

 gigantic trees. The numbers, however, thus obtained, can only be looked upon as approx- 

 imations to the truth, seeing that the zones of wood vary very much in thickness, not 

 only one with the other, but in parts of the same ring. 



Size is no indication of the age of a tree, as various species grow at very different rates, 

 and the same species under different circumstances. The following table shows the diffe- 

 rent rates at which some common trees grow. 



Some trees attain an enormous size by their rapid growth. Species of Eucalyptus have 

 been measured that reached a height of 250 feet, and measured 70 feet round their trunks. 



The death of trees does not appear to arise from an}' natural period being assigned to the 

 existence of their living tissues, or reproductive powers. When the tissues of a tree are very 

 old, they lose their vitality, especially in the center of the trunks of the trees; and, on 

 being exposed to the atmosphere, or moisture, they readily decay. The process of new 

 growth is sometimes more rapid than this deca}^, and thus trees exist M'ith enormous cavi- 

 ties in their interior. The time, however, comes, sooner or later, when a separation takes 

 place between the roots and branches, and then the tree ceases to exist, although the tis- 

 sue that has been conveyed away from it, in the form of slips and grafts, may still con- 

 tinue to flourish. Thus, the old stump of the Ribstone Pippin Apple is but struggling for 

 life in Ribstone Park, while the slips from its branches adorn a thousand orchards, and 

 the thousands upon thousands of bushels of Ribstone Pippin Apples that 



nuall}"^ consumed. 



