Relation of Annual Rings to Age. 163 



" In cold climates they enable us to determine with accuracy the 

 age of trees and shrubs." Again, Sachs* informs us that: " In 

 woody plants, . . . that grow in a climate in which the 

 periods of growth are interrupted by a cold or wet season, . . . 

 the annual additions to the wood may be recognized as sharply 

 concentric layers, known as annual rings." 



These expressions, then, in which all agree in the main, may be 

 taken as representing the prevailing view at the present time, and 

 in confirmation of them we have certain facts cited from time to- 

 time by various writers and observers. f Mr. P. C. Smith J cites- 

 cases in his own experience as a lawyer, where important legal 

 decisions, involving large property rights, have been based upon- 

 a recognition of this relation ; and he also calls attention to the 

 exact correspondence found to exist between the subsequently 

 developed rings of wood, and the time which has elapsed since 

 surveyor's blazes were made on trees during the closing years 

 of the last century. Similar testimony is also offered by Mr. J. 

 A. Ferrer,§ as the result of his own observation. 



On the other hand, however, Dr. A. L. Childs || brings forward 

 important evidence to the contrary. He cites one instance where 

 a shrub had developed as many rings as it was months old, and also 

 states that, having planted seeds of Acer rubrum for the purpose of 

 making an accurate test, at the age of twelve years he found the trees, 

 had developed from thirty-five to forty rings, or abouc three for 

 every year's growth. Unfortunately, one very important item in this 

 statement is omitted, since the locality is not given. Of the same- 

 nature, also, is the statement made by Dr. Warring^" concerning 

 Ghenopodium album, in which he found that the plant had 

 developed eight well-defined rings at the end of four months' 

 growth. 



The question also frequently arises as to how far the law of 

 correspondence of rings to age will apply to trees of both tem- 

 perate and tropical growth. With leference to this, Dr.. 



* Text Book of Botany, p. 132. 

 t Pop. Science Monthly, Vol. Ill, p. 321. 

 t Ibid., Vol XXIII, p. 552. 

 %Ibid., Vol. XXIV, p. 53. Vol. XII, p. 382. 

 || Ibid., Vol. XXII, p. 204. 

 IT Amer. Jour; of Science, Vol. XIV, 1877, p. 395- 



