136 SCIENCE AND FRUIT GROWING 



made by fruit growers, it appears fairly certain that some varieties 

 of apples do exhibit a marked tendency towards alternate fruiting, 

 and, doubtless, there are other varieties which exhibit an equally 

 marked tendency towards consecutive fruiting, though such 

 instances, naturally, do not attract special attention. It would 

 be necessary, therefore, in a strict examination of this subject, 

 to treat the results with each variety separately. This has 

 been possible in the case of four sets only (2 to 5 in the above 

 table), and, consequently, more weight must be attached to these 

 than to the results from those of the mixed plantations, I and 6. 

 The good and poor fruiting of a plantation as a whole in alter- 

 nate seasons, must argue against any tendency in the individual 

 trees towards alternate fruiting, for it shows that this alteration 

 of bearing has been determined by some extraneous circumstance 

 which has affected all the trees alike ; whereas if there were any . 

 innate tendency towards alternation, it would not be exhibited 

 by different individuals in the same year, and, consequently, 

 in a plantation consisting of many individuals, even of the same 

 variety, an average uniformity of production would result. But 

 that there is a tendency towards alternate fruiting of a plantation 

 as a whole, there can be very little doubt, at any rate in the case 

 of most of the trees at Ridgmont : the results obtained there 

 with Stirling Castle, Bramley and in the Variety plantation are 

 set out on the page opposite, the numbers giving the relative 

 magnitude of the crops, compared, in the case of Stirling Castle, 

 with the crop in 1900 as 100, and, in the other cases, with that 

 of 1911 as loo. 1 



A plus or minus sign has been placed after the values showing 

 whether they are above or below the means of the preceding and 

 succeeding seasons. The extent to which these signs alternate, 

 though not without some irregularities, is very remarkable, and 

 when the results are examined on more strictly mathematical 

 lines, it is found that the correlation between the behaviour in 

 alternate seasons is undoubted : further, it appears that there 

 is an independent correlation, not merely between consecutive 

 seasons, but between any one season and those preceding it in 

 the third and fourth places : so that we must conclude that 

 fruit trees have, so to speak, long memories, and that their 

 behaviour in any particular season is conditional, not merely 

 by immediately antecedent circumstances, but by their previous 

 behaviour during at least the three foregoing seasons. To 



1 These values differ in some details from those given in the Fifteenth 

 Woburn Report, having been recalculated on a slightly different basis. 



