HORTICULTURE. 837 



of the dust mixtures indicate that tliis may be due partially to the fact that the 

 particles of the dust mixture are flue enough to lodge in the dense mat of fine 

 plant hairs covering the leaves and partially to the adhesive nature of some 

 of the lead compounds. Generally speaking, the time of application of dust 

 does not differ from that of applying the spray, except that Justing may be 

 conducted profitably on foggy days subsequent to a heavy early morning rain, 

 whereas spraying could not be done because of wet ground and the drip from the 

 foliage. Under the conditions of the experiments, no inconvenience was experi- 

 enced from breathing the dust and no unfavorable symptoms of anything lilie 

 lead poisoning. The eyes should be protected ; otherwise no si^ecial equipment 

 is necessary. 



With reference to the relative importance of dusting and spraying, the au- 

 thors conclude that in the light of present knowledge the trees must be sprayed 

 in the dormant stage just as in the i)ast. Summer sprayings will doubtless 

 continue in the smaller orchards. Where the orchard is of such an extent that 

 it is practically impossible to keep enough outfits to do the spraying at critical 

 times, the duster will afford, necessary relief. In view of the ease with which 

 (lust is applied, it appears to be especially applicable to the general farmer 

 with a few trees in the home orchard who rarely ever sprays. 



Dusting' the apple orchard, D. Kkddick (Fruit-Grower and Farmer, 26 

 {19J5), No. .5, pp. 7. ^!), figs. 2). — ^A popular resume of the experiments made at 

 the Cornell Station in substituting dusting for spraying. 



Influence of the axillary shoot on the development and composition of the 

 peach, A. Manaresi and A. Draghetti (Bui. Vffic. Assoc. Ort. Prof. Ital., 3 

 {1915), No. 1, pp. 8-11). — ^A comparative study was made of peaches provided 

 with axillary shoots and those not accompanied by axillary shoots during their 

 growth. 



The data as here presented indicate that those peaches which are provided 

 with axillary shoots are on the average the heavier, and that the difference in 

 weight is greatest when the tree is vigorous and receives plenty of sunlight. 

 The presence of the shoots somewhat retards the maturing of the fruit. The 

 peaches from trees provided with shoots are less firm and apparently more acid 

 and richer in dry matter. 



Native American species of Prunus, W. F. Wight {U. S. Dept. Agr. Bid. 

 179 {1915), pp. 15, pis. 13, figs. .'/). — This work contains botanical descriptions 

 of the native American species of Prunus and their hybrids. The subject matter 

 is ba.sed on a study of nearly all the species in the field, of more than 400 

 horticultural varieties, and of the collections of this Department and various 

 institutions throughout the country. lutrodtn'tory considerations deal with the 

 distribution, variation, and adaptability, early history, early botanical descrip- 

 tions, and horticultural history and development of American plums. A synopsis 

 and key to the species is then given, after which the species are described in 

 detail with reference to their synonymy, literature, characteristics, distribution, 

 and varieties. A bibliograjihy of cited literature is appended. 



Pruning' stone fruits, O. B. Whipple (Mo. Bui. Com. Hort. CaL. 4 (1915), 

 No. 1, pp. 1-7). — A paper on this sul)ject based on the author's personal obser- 

 vations and experience in pruning apricots, sweet and sour cherries, nectarines 

 peaches, and iilunis. The methods of pruning are discussed with special refer- 

 ence to the maintenance of desirable types of fruiting wood. 



Ampelographical studies, J. Marques de Carvalho (Bol. Dir. Qeral Agr. 



[Portugal], 10 (1912), No. 5, pp. 302, figs. 130). — The present work was prepared 



under the direction of the Portuguese Department of Agriculture and comprises 



monographs of the varieties of Vitis vinifera. A complete botanical descrip- 



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