JOURNAL 



OF THE 



ROYAL HORTICULTURAL SOCIETY. 



Vol. XLI. 1915. 

 Part L 



TREES OF THE CAMBRIDGE BOTANIC GARDEN. 

 By R. Irwin Lynch, M.A., V.M.H., A.L.S. 



[Read February 16, 1915 ; Mr. J. Cheal, V.M.H., in the Chair.] 



The Cambridge Botanic Garden was established on its present site in 

 1846. From sixty-eight to sixty-nine years have now elapsed, and during 

 that time the collection of trees has grown up to form an important 

 feature ; some indeed are finer than can be found elsewhere in the British 

 Isles ; one or two, I believe, are not surpassed in Europe ; and a number 

 of others, some among them planted in comparatively recent years, have 

 attained a development on account of which they attract attention. 

 This, I think, is a good result ; it has come about, not through any 

 natural advantage, but in spite of poor soil and dry climate. The soil 

 is light and deficient in clay, permeated with chalk, and stony ; it is 

 thus the reverse of retentive, and with free drainage below is liable to 

 be very dry. The subsoil is sandy ; below comes a chalky marl, next 

 gravel, and then the blue clay known as gault, which is reached at 

 a depth of 11 or 12 ft. Surface water stopped by the gault may be 

 found from 8 to 12 ft. down, but this does not seem in the least to help 

 the soil above. Rainfall amounts to an average of about 21 inches per 

 annum, but it is the long dry periods, I believe, that are really trying. 

 Shelter is such that wind is always noticeably much stronger on going 

 out into the open country, but easterly winds are certainly felt quite 

 keenly in spring. We are situated on the south side of the town of 

 Cambridge, about the middle of the alluvial plain of the river Cam 

 and its tributaries. The highest part of the garden is 43 ft. above the 



VOL. XLI. B 



