■36 BULLETINS OF THE BUREAU OF PLANT INDUSTRY. 



seeding — Directions for storing the seed — Detailed conditions and results of 

 storage experiments — Packing for transportation — Methods of making gei'- 

 mination tests — Effect of temperature on germination — Summary — Descrip- 

 tion of Plates I and II. The crown-gall and hairy-root diseases of the apple 

 tree : Introduction — Two distinct diseases, crown-gall and hairy-root — Types 

 of apple crown-gall — Effect upon the length of life of the apple tree — Sugges- 

 tions to nurserymen — Data desired. Pejipermint : Description — Countries 

 where grown — Peppermint cultivation in the United States — Cultivation : Con- 

 ditions injurious to crop — Harvesting and distillation — Description of .still — 

 Peppermint oil and menthol — Export of peppermint oil — Prices of peppermint 

 oil. The poisonous action of Johnson grass. 



No. 91. Varieties of Tobacco Seed Distributed in 1905-G, with Cul- 

 tural Directions, l^y A. D. Shaniel and AV. AV. Cobey, 

 In Charge of Tobacco Breeding Experiments, Laboratory 

 of Plant Breeding. 190G. 40 pp., 9 pis. Price, a cents. 



Contents: Introduction — Description of varieties : Cigar-wrapper tobaccos ; 

 Sumatra ; Connecticut Havana ; Connecticut Broadleaf ; cigar-filler tobaccos ; 

 Cuban; Zimmer Spanish; Little Dutch; pipe tobaccos; North Carolina Bright 

 Yellow; Maryland Smoking; plug tobaccos; White Burley ; Orinoco and 

 Yellow Mammoth ; Virginia types (Blue Pryor, Sun-Cured, and AYhite Stem) — 

 Directions for culture: Sumatra tobacco; Connectic\it Havana tobacco; Con- 

 necticut Broadleaf tobacco; Cuban tobacco; Zimmer Spanish and Little Dutch 

 tobaccos ; Maryland Smoking tobacco ; Xorth Carolina. Tennessee, and Vir- 

 ginia tobaccos ; White Burley tobacco — Insect enemies — Directions for saving 

 seed — How to secure good seed — Description of plates. 



* No. 92. Date Varieties and Date Culture in Tunis. By Thomas H. 



Kearney, Physiologist, Plant Breeding Investigations. 

 190G. 112 pp., 10 pis., 52 figs. Price, 25 cents. 



Contents : Introduction — Characteristics of the region : Geography ; the 

 Jerid ; the Nefzaoua ; Gabes ; Gaf sa ; climate ; temperature ; atmospheric 

 humidity ; precipitation ; irrigation and drainage ; water supply ; irrigation 

 system ; drainage system ; soils of the Jerid region ; texture ; fertility ; 

 alkali — Culture of the date palm: Size and value of the gardens; labor and 

 tenantry system; propagation; preparing the land; planting; irrigating; 

 manuring; other cultural methods; pollination and male palms; ripening; 

 harvesting ; preserving- — Varieties of the date palm in Tunis : Descriptions of 

 the varieties; varieties of jirimary importance; soft dates; dry dates; varie- 

 ties of secondary importance; dry dates; soft dates; varieties of minor im- 

 portance ; dry dates ; soft dates ; varieties imported but not included in the 

 l<ey ; varieties included in the key but not imported ; descriptive key to the 

 characters of the fruits; synopsis of the groups; key to the varieties — Index — 

 Description of plates. 



* No. 93. The Control of Apple Bitter-Eot. By W. M. Scott, 



Pathologist. 1906. 36 pp., 8 pis., 1 fig. Price, 10 cents. 



Contents : Introduction — The disease and its cause : The diseased spots on 

 the apple ; the bitter-rot fungus ; the mycelium ; summer spores ; ascospores ; 

 germination of the spores ; bitter-rot cankers on the branches ; source of 

 infection and spread of the disease ; influencing conditions ; weather ; mois- 

 ture ; temperature; susceptibility of different varieties — Remedial measures — 

 The Virginia experiments: The experimental trees; the ]3lan of the experi- 

 ment; object; spraying scheme; weather conditions attending the experi- 

 ment; results; beneficial effects of spraying; effect of the treatment on other 

 diseases; scab; leaf-spot; sooty-blotch; injurious effects of the treatment; 

 russeting; coating of Bordeaux mixture — Commercial o]ierations: Results in 

 several orchards — Preparation of Bordeaux mixture — Method of applying 

 Bordeaux mixture — Conclusions and recommendations — Description of plates. 



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