1»1»] HORTICULTUKK. 445 



ence In the appearance of Soya] Ann cherry trees on maacard and on mahaleb 

 stocks. The mahaleb Btock has Called Co dwarf any of the cherrlea, The Drake 

 and Ne Plus Ultra almond trees have made practically toe same growth on 

 myrobalan, peach, and almond roots. Burbanh plums made the largest per- 

 centage of gain on peach stock, but'have made satlafactoiy growth on myro- 

 balan and almond stock. The Royal apricots have hkhIo slightly better growth 

 on peach stock than on myrobalan, almond, and apricot stocks, of the five 

 different fruits grown on the myrobalan, peach, almond, and apricot stocks, 

 four showed the largest gains for the first year on peach root. The difference 

 observed between these stocks appears to decrease cacti year. 



In April, 1917, a severe test was made to determine whether asphaltum could 

 be used as a protective coating against rabbits or borers without injuring t tic- 

 trees. The asphaltum was applied to the trees from top to bottom, all of the 

 buds being covered without any noticeable injury to the bark of any of the 

 trees. The results indicate, however, that the asphaltuin should be applied as 

 soon as possible after the trees are planted in order to keep out the borers. 



Orchard spraying- v. dusting, N. J. Giddings (West Virginia Sta. Bui. 167 

 (1918), pp. 18, figs. 2). — This bulletin reports a series of experiments conducted 

 during a period of five years in both apple and peach orchards to determine 

 the value of dust treatments as compared with ordinary methods of spraying. 

 The peach dusting experiments are described in detail, and a brief general 

 statement is given of the work with apples. The detailed results with apples 

 are to be reported at a later date. 



Sulphur dust was found quite effective against peach scab and brown rot. 

 The dust treatments have also been found very effective for the control of biting 

 or chewing insects. It is believed that the dusting method may be of much 

 practical value in peach orchards. 



Alter four years of experimental work it is not felt that the dusting method 

 is to be recommended in West Virginia apple orchards whore scab or sooty 

 blotch Is severe, or for the treatment of bitter rot, black rot, or blotch, uuless it 

 is used primarily for the control of insects, such as codling moth, curculio, 

 cankerworm, or caterpillar. In apple orchards where It is difficult to use a 

 spraying machine, or where It is difficult to obtain water, the dusting method 

 will be of considerable benefit for insect control. 



The cost of materials required for efficient dust applications is considerably 

 greater than for sprays. Relative to labor and time required, however, it was 

 found that one man and a driver with a dusting outfit can dust between three 

 and four times as many trees per hour as two men and a driver can spray 

 with the ordinary power-spraying outfit. With the spraying outfit it was cus- 

 tomary to handle two rows at a time and short but frequent stops were nec- 

 essary. The dusting machine usually covers three rows at a time and the team 

 is kept moving at a good walk. 



Why prune bearing apricot trees heavily? W. P. Tufts (J/o. liul Cat 

 Com. Hort., 8 (1919), No. 1, pp. 15-21, figs. 8).— In this paper the author presents 

 some results of experiments conducted by the division of pomology of the 

 University of California which indicate that It is not desirable to follow the^ 

 customary practice of severely cutting back the annual growth of apricot trees. 



Although the experiments have not proceeded sufficiently long to warrant 

 definite conclusions as to the proper system of pruning, the work thus far con- 

 ducted indicates that some form of pruning should be adopted which will pro- 

 vide for a moderate amount of new growth which may be retained for fruiting 

 purpose from three to five years and then cut away. The present system of 

 heavy annual pruning is frequently followed by sunburned branches and, in 

 many cases, by lighter yields than are believed to he necessary or desirable. 



