No. 3, April, 1921] PATHOLOGY 295 



2055. Hyde, W. C. Orchard experiments in Stoke district. New Zealand Jour. Agric. 

 21 : 81-83. 1920. — Experiments for control of peach brown rot, apple leaf hopper, and apple 

 black spot (scab). Four types of spray materials were tested, and several varieties of fruit 

 were included in some of the experiments. Some general conclusions are given. — N. J. 

 Giddings. 



2056. LovETT, A. L. Insecticide investigations. Oregon Agric. Exp. Sta. Bull. 169. 

 65 p., fig. 1-12. 1920. — The use of spreaders in conjunction with many poison sprays increases 

 adhesiveness, causing a more even coating of the surface to which they are applied. Arranged 

 in order of commercial desirability some of these spreaders are "caseinate" (a mixture of 

 casein, hydrated lime and water to form a thin paste), gelatin, glue, Irish moss, and soap 

 bark. While miscible oil emulsion may prove a very valuable spreader, it is not definitely 

 recommended at this time. Other substances, such as cane sugar, glycerine, tea made from 

 sage-brush, and gum arable were also used but with indifferent success. Tests on the use of 

 materials with arsenate sprays to render them non-injurious to foliage, and on the action of 

 nicotine sulphate sprays are reported. — E. J. Kraus. 



2057. McMtTRRAN, S. M. Pecan rosette in relation to soil deficiencies. Amer. Nut 

 Jour. 10:38-39, 43. 1919. — Pecan rosette is the most serious trouble to which pecan trees 

 are subject. Earliest stages of disease are indicated by a few small, wrinkled, yellow-mottled 

 leaves at end of branches. Trees are so weakened that they are often killed by winter injury 

 or borer attacks, though they do not die as a direct result of the disease. Deficiency in humus 

 and soil moisture is given as the cause of the disease. Cover crops, especially legumes, are 

 recommended as a remedy. Deep sands and eroded hillsides should be avoided. — E. L. 

 Overholser. 



2058. McMuRRAN, S. M. Preventing wood rot in trees. Amer. Nut Jour. 10:40-41. 

 1919. — Wood-rotting fungi gain entrance through unprotected wounds on trees and are ulti- 

 mately the cause of serious losses. In top working, stubs should not be left and sloping cuts 

 should be avoided. Wounds should be covered with waterproof material until healed. The 

 long growing seasons and hot, humid climatic conditions of the southern states are very favor- 

 able for development of wood-rotting fungi. — E. L. Overholser. 



2059. Pritchard, F. J., and W. B. Clark. Effect of copper soap and of Bordeaux soap 

 spray mixtures on tomato leaf spot. Phytopath. 9:554-564. 7 fig. 1919.— Experiments, 

 based chiefly upon the yield of fruit, are reported in tabular form on the use of different spray 

 materials in controlling leaf spot. The cheap copper soap mi.xture 0.5-0-3-50 increased 

 the yield as much as Bordeaux. It was not so effective as Bordeaux soap 4-2-3-50 or 

 Bordeaux mixture ^4-50 in controlling the disease on the foliage under field conditions; 

 but as it increased in yield fully as much as the others it was the most economical of the three 

 spray mixtures. — J. G. Dickson. 



2060. SiMONETTo, M. Criterios sobre la destruccion de plagas y de las enfermedades en 

 general de las plantas y de la mosca prieta en particular. [The destruction of plagues and dis- 

 eases of plants in general and of the fly (Aleurocanthus Woglumi) in particular.] Rev. 

 Agric. Com. y Trab. 3 : 164-169. 1 fig. 1920. 



2061. Walton, R. C. The control of frog-eye on apple. Pennsylvania Agric. Exp. Sta. 

 Bull. 162. 39 p., 18 fig. 1920. — Frog-eye, caused by Physalospora cydoniae, often causes 

 almost complete defoliation by August in certain parts of Pennsylvania. This results in 

 undersized fruit, loss of vitality, weakened fruit buds, and eventually death of the trees 

 unless protection is afforded.— The reported experiments were conducted upon York Imperial 

 and Stayman Winesap trees in three different orchards during the years 1918 and 1919. 

 Bordeaux mixture, lime-sulphur, "Pyrox," "Sulfocide," and sulphur dust were used. 

 By means of extensive bagging experiments it was found that more than half of the total 

 infection takes place within the period of eighteen days after the petals fall. This is appar- 



