December 20. 1,900] 



NA TURE 



177 



Thus R. anglosaxoniciis has four subspecies and R. dume- 

 torutn eight varieties, and of the latter Mr. Rogers says, 



" Other undescribed forms of this aggregate no doubt 

 exist in Great Britain, and a further study of these may 

 possibly justify the addition of one or more new varieties 

 to the preceding list." 



Thirteen of the species and a fair proportion of the 

 varieties and subspecies are peculiar to the British Isles, 

 occurring mainly in very restricted areas. R. durescens, 

 for instance, is known only in Mid-Derbyshire, and R. 

 mercicus is " at present known with certainty only between 

 Water Orton and Minworth, Warwickshire." 



We do not wish to underrate the value of the work of 

 Mr. Rogers and his fellow-batologists, who, moreover, 

 are not wholly responsible for the present state of bat- 

 ology. They are disciples of Dr. W. O. Focke, of 

 Bremen, whose epoch-making visit to England in 1889 

 is referred to almost as the missionary visit of an apostle. 

 The handbook is a monument of patient toil and critical 

 examination ; each species, subspecies and variety is 

 described with a care and fulness which many botanists 

 would do well to emulate ; notes on habitat are given, 

 the distribution, if any, on the Continent is recorded, and 

 there are also many remarks of a critical nature on the 

 affinities of the form in question. An appendix contains 

 a list of the botanical counties for which each species 

 is recorded ; and the thorny path of the student is some- 

 what eased by a key to the groups and a brief conspectus 

 of the species which precede the detailed descriptions. 



As a study in the variation of a highly variable species, 

 the book is a store of valuable information, which, if 

 carefully collated and arranged, might yield results of 

 great interest, especially if more particulars as to habitat 

 and environment were included. However, Mr. Rogers' 

 aim has been to record and systematise, for the benefit 

 of students of batology, facts already ascertained, and he 

 has carried out his task in a manner which, except for 

 a few details, is beyond criticism, and calls for the 

 gratitude of all batologists present and to come. 



A. B. R. 



EXPERIMENTAL FRUIT-FARMING. 

 Report of the Working and Results of the Woburn 

 Experimental Fruit Farm. By the Duke of Bedford 

 and Spencer U. Pickering, F.R.S. Second report. 

 Pp. V + 260. (London : Eyre and Spottiswoode. 

 1900.) 



IN few deipartments of plant cultivation is empiricism 

 more rampant than in the cultivation of fruit-trees. 

 The methods of pruning and other cultural details have 

 been handed down from our forefathers with little or no 

 attempt to regulate them by scientific methods, whilst, in 

 too many instances, absolute neglect has prevailed and 

 fruit-growing has, in consequence, been deemed unprofit- 

 able at the very time when thousands upon thousands of 

 barrels of apples are imported annually from the United 

 States, Canada and Tasmania. In some cases this 

 foreign supply comes in when our own crop is exhausted, 

 but, speaking generally, a very large proportion of the 

 fruit crop might be grown here just as well as in the 

 States were our farmers endowed with the same business 

 capacities as their brethren across the Atlantic. Recog- 

 NO. 1625. VOL. 63] 



nising the importance of these facts, the Duke of Bedford 

 has established near Woburn an experimental fruit-farm, 

 where, under the directions of Mr. Pickering, experi- 

 ments are being carried out on various cultural methods 

 applied to fruit trees and to bush fruit. At the same 

 time, demonstration plots are planted with a view of 

 showing to the farmers what kinds of apples and other 

 fruit trees may be grown in that particular locality with a 

 reasonable expectation of profit. 



The farm has now been established for five years. 

 The first report, published three years ago, was natur- 

 ally devoted largely to a general account of the ground 

 and of the experiments then commenced. The present 

 volume deals more largely with results. Those who have 

 no leisure to investigate the statistical details will be able 

 to glean a good general idea of their purport from the 

 perusal of the table of contents and the general summary 

 given in the appendix. 



The experiments made with a view of destroying the 

 currant-bud mite were very numerous and very unsatis- 

 factory. Although at Wye College the use of hydro- 

 cyanic vapor has been found serviceable, it was found of 

 no avail at Woburn. It would seem, however, that our 

 efforts will be negative until we know more of the life- 

 history of the mite. Perhaps the study of the manners 

 and customs of the hazel-bud mite might furnish a useful 

 clue to our knowledge of the nearly allied currant- 

 bud mite. 



Eighty-five varieties of strawberries were under obser- 

 vation, but it was not found possible to trace any definite 

 connection between the amount of the crop they furnished 

 and the meteorological phenomena to which the plants 

 were subjected. Moreover, the results of the application 

 of manures, artificial or natural, are stated to be " am- 

 biguous," a fact which points to the inference that the 

 soil is sufficiently fertile without the application of 

 manure. 



The results of pruning at various times and of diflferen 

 methods of performing the operation are tested by 

 weighing a certain number of leaves from the trees, 

 and by measuring the height and girth of the trees. 

 From these experiments, it would seem as if further 

 time is required to estimate the value or otherwise 

 of the different methods of pruning. Root pruning, a 

 practice largely adopted by gardeners to check undue 

 luxuriance and promote fertility, is made the subject of 

 other experiments by Mr. Pickering and his lieutenant, 

 Mr. Castle. Although root pruning acts as a check tp 

 vegetation, it generally also results in the formation of a 

 large quantity of fibrous roots and root-hairs, so that the 

 absorbent power of the roots must be increased, and we 

 might have expected the vegetation to be correspondingly 

 enhanced. There is a little inconsistency here which we 

 hope the Woburn experiments may ultimately clear up. 



Perhaps the most striking result yet obtained is that 

 showing the injurious effect of growing grass round the 

 fruit trees, the injury being attributed to the increased 

 evaporation from the soil and the consequent exposure of 

 the trees to drought. Many of our orchards are in grass, 

 but as they are "fed off" by sheep the injurious results 

 may, in a measure, be counteracted by the m.anure so 

 supplied. Other experiments we can not here further 

 allude to, but, in conclusion, we cm but emphasise the 



