180 REPORT OF OFFICE OF EXPERIMENT STATIONS. 



Studies on the life histories of sugar-beet insects were continued, 

 and the army cutworm and other species of cutworms were inchided 

 in the list. It Avas observed that the root louse could be kept out by 

 keeping the land free from weeds in the early spring. A pajDer was 

 }iublished on the oyster-shell scale, but studies on the life history of 

 this insect as well as on the parasites attacking it are continued. 



In connection with the investigations on arsenic poisoning of fruit 

 trees, the disease known as collar rot was studied. The effect of 

 arsenic was observed by its application to clean, healthy roots of 

 fruit trees, and the results indicated that under some conditions 

 f,rsenic corroded the bark. Apparently arsenic spraying results in 

 injury wherever the bark of the tree has been opened, while on older 

 uninjured bark there is but little effect. The orchard-disease work 

 was mainl}^ upon apple canker, which is a Montana disease, black 

 heart, and the collar rot in connection with the arsenic investigation. 



The results in the soil-moisture project, as well as those in nitrate 

 Avork, are reqdy for publication, although further work along these 

 lines will be conducted. It ajjpears that where the moisture content 

 is good the nitrate formation is relatively high. In these studies it 

 has been shown that the great benefit from summer fallow is due to 

 the nitrates accumulated in the moist soil during the fallow season, 

 which gives a rapid growth the following year, so that the crop 

 usually has advanced be^^ond the stage of liability to serious injury 

 before the dry period of the year arrives. The moisture studies were 

 carried on under dry-farming conditions at the substation at Forsyth 

 and on the Fort Ellis farm 3 miles east of the station. Moisture de- 

 terminatons are made every 10 days throughout the cropping season 

 to a depth of 5 feet, and at the beginning and end of each season to 

 a depth of 12 feet on plats handled under different rotations. The 

 nitrate determinations are made on samples taken to a depth of 3 feet 

 on the same plats every 20 days. 



In the seepage projects T different soil types are under observation. 

 These soils are placed in tanks and the movement of water through 

 them is studied. In addition to this laboratory work the seepage on 

 canals running through the different types of soil is studied during 

 the growing season. It has been found that the governing factor in 

 seepage is the nature of the soil, and that each particular soil type 

 must be dealt with separately. 



In the wool project a start was made with 20 pure-bred Ram- 

 bouillet ewes. The variations in the wool were observed to be very 

 wide. Tests were made of samples from different parts of the fleece 

 to find the most representative part. In microscopical and histolog- 

 ical studies of wool the diameter, crimple, luster, etc., are determined. 



The various departments of the station also report progress during 

 the year in the various lines of work conducted with the Hatch fund. 



