366 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



CONTRIBUTIONS FROM THE WISLEY LABORATORY. 



XV. — Pollination in Orchards.-— II. 



The Flowering of Pears. 



By F. J. Chittenden, F.L.S. 



It was pointed out in a former communication on the flowering of 

 apples * that there appears to be a fairly definite sequence in the 

 order of flowering in varieties of apples, and that the variation in an 

 observed order is, in any year, relatively slight, no matter in what 

 part of the world the trees may be growing. 



In the general introduction to that communication the frequent 

 occurrence of self-sterility among apples was pointed out, and the 

 need for planting varieties flowering at about the same time in close 

 proximity to one another in order that cross-pollination might be 

 easily effected was referred to. Tables were given showing the 

 relative order of flowering of the principal varieties of apples. 



In the present article the relative time of flowering of pears is 

 noted. 



Self-sterility is a phenomenon at least as common among pears 

 as it is among apples, and one long recognized in this country, though 

 frequently lost sight of. In the former article f the work of Waite 

 in America on this subject was alluded to, but an interesting communi- 

 cation to our Society on some work done in this country at a much 

 earlier date was overlooked. This communication shows that the 

 need for the cross-pollination of certain varieties of pears was clearly 

 apprehended by the writer, and it will not be without interest to 

 reprint part of it here. The Rev. George Swayne, writing from 

 Dyrham on August 2, 1822, refers, in a letter J read before our 

 Society on August 6, 1822, to the general unfruitfulness of certain 

 varieties of pears, and goes on to recount some experiments which he 

 made with the object of avoiding this unfruitfulness, as follows : — 



" I am myself possessed of a striking instance of this untoward 

 disposition in an individual of the genus Pyrus, which has for a long 

 time baffled all my attempts to alter its infertile habits ; it is that of 

 a ' Gansell's Bergamot,' which has grown for twenty years or more 

 in its present situation against a wall, part of which has a south-west 

 and part a south-east aspect. 



" The tree has all the appearance of health and sufficient luxuriance, 

 and has been for several years constantly covered with a profusion 

 of blossoms at the proper season, but has never before this borne 

 more than three or four pears in any one year, and most frequently 



* Chittenden, F. J., in Journal R.H.S. xxxvii. pp. 350 et seq. 

 t Loc. cit. p. 350. 



X Transactions of the Horticultural Society of London, V. (1824), 208-213. 



