401 



Petroleum, at the rate of 1 part by weight per 100 parts of spray 

 solution, is another substitute for nicotine. The following is a tested 

 formula : Petroleum 5 lb., Panama bark 1 lb., water 3 gals. The bark 

 is crushed and boiled in the water until about 2| gals, of liquid is 

 obtained ; this is strained through a fine cloth and the petroleum is 

 added by degrees with constant beating until a perfect emulsion 

 results. This is diluted with 50 gals, water. 



Macrum (C. a.). Combined Bordeaux Oil Emulsion Spray. — 15th 

 Bienn. Rept. Oregon State Bd. Hortic, Salem, 1919, p. 82. [Re- 

 ceived 5th July 1920.] 



A spray has been designed that, applied as the buds are opening, 

 will control scab, San Jose scale [Aspidiotus jjerniciosus], Aphids, 

 leaf- roller, red spider {Tetranychus] and curl leaf of the peach, and 

 if it dries thoroughly it will stay on the bark all through the season. 



To make it a 200 U.S. gal. tank is filled three-quarters full of water, 

 and 24 U.S. gals, of copper sulphate solution (1 lb. to 1 U.S. gal. water) 

 are added. Milk of lime, made with 12 lb. slaked lime, is then poured 

 ill until litmus paper shows that the solution is neutral, and 1| gals, 

 of glue solution (1| lb, glue in water) are then added ; twelve U.S. gals, 

 of the General Chemical Company's No. 1 oil emulsion, or a corres 

 ponding one, are stirred with a little water until emulsion is started, 

 and poured into the tank with enough water to make the whole up to 

 200 U.S. gals. 



LovETT (A. L.). The Potato Eelworm.— i5^A Bienn. Rept. Oregon 

 State Bd, Hortic, Salem, 1919, pp. 101-104, 3 figs. [Received 

 5th July 1920.] 



The potato eelworm {Heferodera radicicola'] has been found infesting 

 potatoes in Oregon. It attacks a very large number of difierent kinds 

 of plants, forming the galls on the rootlets known as root knots, but on 

 potatoes the injury is different. The worms form cysts in the tissue 

 of the tuber at a depth of a quarter of an inch or more which appear 

 as brownish rings with a pearly centre. The skin of infested potatoes 

 is usually wrinkled, and there are irregular sunken greyish areas with a 

 raised centre here and there over the surface. Occasionally seed 

 potatoes in the earlier stages will show no outward indication of 

 iiijury. 



H. radicicola has practically ruined the potato industry in the 

 irrigated sections of Nevada, and also occurs in Southern California, 

 in Oregon, where it seems to be confined at present to one locality in 

 Coos County, and probably in Colorado and parts of Utah as a pest of 

 potatoes, and all over the United States on other plants. Once it is 

 established in a field total eradication is probably impossible, the 

 young worms working out of the root in which they have hatched into 

 the soil and mfesting other plants. Seed potatoes should only be 

 obtained from uninfested districts, and should be carefully examined 

 for any suspicious roughness or galls ; even if they seem clean, a number 

 of representative tubers should be broken (not cut) into smaU pieces 

 and carefully examined for the small brown spots in the tissue caused 

 by the cysts. 



