16 HORTICULTURE [Bot. Absts., Vol. VI, 



120. Hendrickson, A. H. Inter-species pollination of plums. Proc. Amer. Soc. Hortic. 

 Sci. 16: 50-52. (1919) 1920. — Studies were made regarding the self fertility of the following 

 varieties: Burbank (P. triflora), Reine Claude (P. domestica) , German Prune (P. domestica) , 

 and Shropshire (P. insititia). The varieties were likewise inter-crossed with the following 

 results as given in the author's summary. — (1) Burbank and German gave evidence of being 

 self-sterile. — (2) Reine Claude and Shropshire gave evidence of being self-fertile. — (3) Bur- 

 bank and Reine Claude are apparently inter-fertile. — (4) Reine Claude, German Prune and 

 Shropshire are inter-fertile. — (5) From these data it is evident that, as far as the varieties 

 tested are concerned there is no sterility existing between P. triflora and P. domestica or 

 between P. domestica and P. insititia. — E. C. Auchter. 



121. Jack, H. W. Preliminary report on experiments with wet rice in Krian. Agric. Bull. 

 Federated Malay States 7: 298-319. 4 fig. 1919. — Krian is the largest padi-growing district 

 in Federated Malay States, about 50,000 acres being planted annually with wet rice. The 

 experiments were made with a view to the improvement of yield of grain. Nearly 200 vari- 

 eties were found but only six are used for the main crop. Introduced varieties, 8 Siamese, 9 

 Javanese, 14 Indian, were tried but did not equal the local strains. The cultivation of padi, 

 hybridization, diseases, and pests, are treated at some length. — T. F. Chipp. 



122. Kruckeberg, Henry W. California Bud Selection Association standardizing 

 nursery products. Amer. Nurseryman 31: 100-101. May, 1920. — A general discussion is 

 given of the individuality of fruit trees and the value of propagating from recorded trees. 

 This movement is receiving considerable attention in California, by the prune growers and 

 in the citrus-fruit regions.— J. H. Gourley. 



123. Lamproy, E. Les engrais radioactifs. [Radioactive fertilizers.] Rev. Hortic. 

 [Paris] 91: 393-394. Dec, 1919. — Experiments with this type of fertilizer were conducted on 

 beans, wheat, spring vetch, white pea, flax, potato, beet, Jerusalem artichoke and sun-flower. 

 The effects of the radioactive substances upon the cereals were more pronounced when they 

 were combined with superphosphates, and the larger returns were generally obtained when 

 they were used in connection with complete fertilizers. Approximately 50-60 kilos were 

 applied to each hectare. The influence of the radioactive materials was especially noticeable 

 upon plants producing tubers or thick roots, particularly regarding sugar content. These 

 fertilizers are worthy of trial for use with specific horticultural crops. — E. J. Kraus. 



124. Lewis, C. I., F. C. Reimer, and G. G. Brown. Fertilizers for Oregon orchards. 

 Oregon Agric. Exp. Sta. Bull. 166. 48 p. Fig. 1-3. 1920. — Fertilizer experiments on apple 

 pear, and peach trees in southern Oregon indicated that the chief element needed is nitrogen, 

 which, if immediate results are sought, may be applied in the form of nitrate of soda, nitrate 

 of lime, or sulfate of ammonia at the rate of 6-10 pounds to each old apple or pear tree, and 

 3 pounds to each large peach tree. On some of the very heavy soils, which show a fair amount 

 of nitrogen, it is not profitable to use mineral fertilizers at present. In the Hood River Valley 

 it was shown, through a period of 5 years experimentation, that Newtown and Spitzenberg 

 apple trees with low vigor due to depleted nitrogen supply failed to set fruit well and that 

 there was a marked tendency toward alternate bearing. When available nitrogen was in- 

 creased, however, through the use of either leguminous shade-crops, commercial fertilizers, 

 or both in combination and generally supplemented by irrigation, the fruit set was increased, 

 and in some cases the tendency toward alternate bearing was retarded. Because all orchard 

 practices were not within control each year, conclusive evidence on the latter point was not 

 obtainable. In the case of Spitzenberg apples, increased sizes and yields of fruit were offset 

 at times by decreased quality and color, when very large amounts of nitrate of soda or sulfate 

 of ammonia were used, especially in conjunction with leguminous shade-crops and irrigation. 

 Applications of nitrate of soda to separate plots at intervals of two weeks, from March 6 to 

 May 7, showed that "the early-fertilized Newtowns yielded 7.9, and the Spitzenbergs 10.83 

 loose boxes per tree, as compared to only 2.28 and 1.20 boxes for the latest application. With 

 orchards on heavier soils, particularly, a system of management in which clover only is used 



