No 1, October, 1920] HORTICULTURE 17 



may be expected to keep up soil fertility without the use of nitrate fertilizers. There is 

 need for correlating all orchard practices, such as tillage, irrigation, pruning and cover- 

 cropping. — E. J. Kraus. 



125. Lind, Gustaf. Om forekomsten av vara viktigare skogsbar. [On the occurrence 

 and distribution of our more important bush fruits.) K. Landtbr. Akad. Handl. och Tidskr. 

 58: 175-177. 1919. 



126. Lindley, Paul C. Report of the Southern Nurserymen's Association. Jour. Econ. 

 Entomol. 13: 194-198. 1920. — A report presented to the Section of Horticultural Inspection 

 at the thirty-second annual meeting of the Amer. Assoc. Econ. Entomol., January, 1920. — 

 A. B. Massey. 



127. Macoun, W. T., and M. B. Davis. Progress in apple breeding for the Canadian 

 prairies. Proc. Amer. Soc. Hortic. Sci. 16: 13-18. (1919) 1920. — In 1887 seed of Pyrus baccala 

 was obtained from the Imperial Botanic Gardens, Petrograd, Russia, and sown in Ottawa, 

 Canada. In 1890 young trees from these seeds were sent to different Canadian experimental 

 farms. These trees proved hardy, and, in 1894, 21 varieties of apples used as male parents 

 were crossed on to these crab trees. The resulting fruit in the Fi generation, while not much 

 larger than that of the female parent, was of better quality. At the lower elevations, most 

 of the crosses were quite hardy. Two of the crosses, named Columbia and Osman, were quite 

 hardy in exposed and trying places. — In 1904 the best of the Fi crosses were crossed with 18 

 different varieties of apples. This second infusion of apple "blood" increased the resulting 

 size greatly, but still the fruit was not above the smallest marketable size for apples. Indi- 

 vidual records and dimensions of fruit are given. When Pioneer, a seedling from the cross 

 P. baccata X Tefofsky, was crossed with Mcintosh, Northern Spy, Cranberry Pippin and 

 Ontario, the male parents, especially Mcintosh, exerted a marked influence on quality. — 

 Breeding work will be continued, using P. baccata as the male parent and the Russian varie- 

 ties as female parents, in the hope of getting hardier varieties that will withstand the severest 

 tests on the Canadian prairies. — E. C. Auchter. 



128. Marlatt, C. L. Federal plant quarantine work and co-operation with state officials 

 Jour. Econ. Entomol. 13: 179-181. 1920. — Report presented to the Section of Horticultural 

 Inspection at the thirty-second annual meeting of the Amer. Assoc. Econ. Entomol., January, 

 1920.— A. B. Massey. 



129. Marshall, Roy E. Report of three years' results in plum pollination in Oregon. 

 Proc. Amer. Soc. Hortic. Sci. 16: 42-49. (1919) 1920. — Several varieties of plums of different 

 species were tested as to whether they were self-fruitful, self-fertile, self-sterile, or self- 

 barren. Varieties of Primus domestica were tested to see if these were inter-fruitful. Studies 

 were also made to see whether varieties of P. domestica and P. triflora were inter-fruitful. 

 The author's summary is as follows: (1) Pollen of the varieties of Prunus domestica and P. 

 triflora seem to germinate best in a solution of 5 per cent cane sugar and 2 per cent gelatin. — 

 (2) If there is a normal bloom and 1 flower in 20 matures into a fruit, the result may be a 

 full crop in some cases, while in some others 1 in every 2 or 3 flowers should set to mature a 

 full cro". Generally, 1 flower in 5 should set. — (3) Thirteen of the 23 varieties tested are 

 evidently self-barren. Blue Damson is decidedly self-fruitful. Italian and Petite are par- 

 tially self-fruitful. The other varieties should be considered virtually (commercially) self- 

 barren. — (4) The varieties of P. domestica may be considered as inter-fruitful. — (5) Italian 

 and Petite are each good pollenizers for practically all varieties of P. d-omcslica tested. — 

 (6) It is not necessary that one be particular as to which of the varieties of P. domestica com- 

 monly grown in the Pacific Northwest are planted together, provided they bloom at approx- 

 imately the same time. Some varieties are commercially profitable where no pollenizers 

 are used. — (7) In such varieties as Italian, Petite, Sugar and Golden Drop, the pericarp 

 ceases development soon after the seed dies and the fruit soon falls. — (8) In such varieties as 

 Bavay, Blue Damson, Giant, Green Gage, Pond, Quackenbos, Red Magnum Bonum, Tennant 



BOTANICAL ABSTRACTS, VOL. VI, NO. 1 



