350 EXPEKIMENT STATION RECORD, 



same time strengthen the opmion that a moderately severe pruning is highly bene- 

 ficial. Trees given the latter treatment have grown vigorously, developing clean, 

 new, thrifty tops, and this season were covered with healthful, dark-green foliage. 

 For the most part they were loaded with attractive fruit of fine quality. On the 

 other hand, trees which were pruned lightly after the usual plan of heading in and 

 thinning out part of the new growth have grown more slowly, were marked by 

 smaller, less thrifty foliage, bore fruit of smaller size and poorer quality, and this fall 

 contain much more dead wood. But it must l)e admitted that no manner of i^runing 

 will entirely renovate a badly frozen tree. There is hardly a tree above 4 years old 

 on the station grounds that is not rotten in trunk and main branches and is held 

 together only by the new growth which has been made since the freeze. This being 

 the case, the trees broke down badly in winds and under their weight of fruit this 

 season. But trees well cut back, having made a greater development of new t^'ood, 

 were better able to resist influences which tended to break them down, and doubt- 

 less their lives will be considerably prolonged." 



Results obtained in experiments in thinning favored more severe thinning of 

 peaches than is commonly practiced. A distance of 10 in. between fruits seemed to 

 be none too great in the case of the varieties experimented on. In the experiments 

 with i^ears early spraying with copper sulphate (1 lb. to 15 gal. of water) proved less 

 efficient in the prevention of scab than late spraying with Bordeaux mixture just as 

 the fruit buds were about to oj)en. 



Grapes at the station containing vinifera blood fruited sparsely, mildewed badly, 

 and many were inclined to be tender and weak growers. The varieties best adapted 

 for general cultivation in the climate of the station were Winchell, Diamond, Worden, 

 Niagara, Concord, and Delaware. 



Of the foreign chestnuts grown the Paragon was by far the best variety among 

 either the European or Japan kinds. Likewise the Japan walnut {Juglnns seiboldii) , 

 the author states, grows rajjidly, and makes a handsome tree for ornamental pur- 

 poses. The nuts are borne abundantly in large clusters. The quality is good but 

 not high. An English walnut has grown but 5 ft. in height in 11 years, and has as 

 yet shown no signs of fruiting. 



Winter irrig-ation of deciduous orchards, A. J. McClatchie {Arizona Sta. Bui. 

 37, pp. £07-£40, Jigs. 9). — The greater value for orchards in southern Arizona of win- 

 ter over summer irrigation has been pointed out by the station in earlier reports (E. 

 S. R., 12, p. 1042). Some data have also been given showing the effect of winter 

 irrigation on crop and orchard production, and on the moisture content of the soil 

 throughout the season, to a depth of 34 ft. The work here reported includes the 

 earlier work and some additional data. Some meteorological records are incorporated 

 and a discussion given of the principles involved in winter and summer irrigation. 

 In 1899-1900 irrigation of a portion of a peach and apricot orchard was begun Decem- 

 ber 16 and continued at intervals until March 5, when 3 ft. of water had been applied. 

 No further water was given for the next 8 months, and only 2\ in. of rainfall, divided 

 among 5 showers, fell during this period. The orchard was plowed each way about 

 1 ft. deep as soon as it was dry enough in the spring and harrowed thoroughly. 

 After each rainfall it was again harrowed to break up the crust that formed. As in 

 the previous year the orchard thus treated showed no signs of drought and made a 

 vigorous growth throughout the season. Both apricots and peaches matured a heavy 

 crop of fruit of good quality. The season, especially May and June, was the hottest 

 and driest ever known in the vicinity of the station. At the end of it the experi- 

 mental orchard had a thrifty, vigorous appearance, while many other orchards in the 

 vicinity of the station had died. 



The great advantages of winter irrigation for orchards are stated by the author as 

 follows: "During the winter the lower temperatures and the higher relative humidity 



