IN-JURIOCS INSECTS AND OTHER LOWER ANIMALS. - GENERALITIES I715 



1237 -Seeds of Weeds and of Cryptogamic Diseases observed in Sowing Cereals from 

 the Maritime Province of Eastern Siberia. — Sco N' 1174 of this Bulletin. 



1238 -An Attempt to Destroy Wild Mustard (Brassi'ca Sinapistrum), in Fields 



of Cereals. — Dusskrrk, C, in Tnnaux dc Chiiitic ulimcn!aii-c cl d'Hy-^Tcnc, Vol. \"II, 

 Part 6, pp. 357-358. Berne, 1916. 



In order to replace the sulphates of iron and copper, and powdered 

 kainite, which have been used hitherto to destroy wild mustard and are 

 now expensive and difficult to procure, the writer made experiments in 

 spra^dng with a 20 to 30 per cent solution of potassium chloride, which 

 can be procured in sufficient quantities at its original price. Trial was made 

 on April 28, 1916 on an oat field atEcublens (Vaud), which was overgrown 

 with wild mu.stard, the plants having 2 or 3 leaves unfolded. The result 

 was very satisfactory: the plants touched by the liquid were completely 

 shrivelled up; the few wliich had received less of the solution withered and 

 appeared to be verj- sickly. The field in this way was cleared of this weed 

 and the oats developed vigorously. Plants of Ranunculus sceleratus which 

 were common in the field were also destroyed. 



The writer suggests that more concentrated solutions should be em- 

 ployed (55 lbs. of a 30 per cent salt in 22 gallons of water) and that it shoulil 

 be sprinkled on to the plants by means of a vine sprayer on a fine morning 

 after heavy dew. For a field that is badly infested one must reckon about 

 352 lbs. of salt dissolved in 1092 gallons per acre; the solution is prepared 

 simph' b}' placing the proper amount of the solid in a bag and suspending 

 it in the measured amount of water. This treatment has no bad effect 

 upon the cereal and represents, in fact, a very fair amount of potash manure, 

 which can onh^ have beneficial effects upon the harvest. 



INJURIOUvS INSECTS AND OTHER LOWER ANIMALS. 

 1239 - Animal Pests on Cultivated Plants Observed by the Entomological Bureau of generalities 



Stavropol in 1914. — rv.VRoV, B., in Rapport siir lc:i Iravaiixdu Biinau cntumolo^^ique 

 de Stavropol an Caucase pour rannce 1914, pp. ioj-105. Petrograd, 1916. 



The most important among the insects which are pests upon cultivat- 

 ed plants in Stavropol is the migratory locust [Pachyfylus migrator ins 

 L.) which was observed in 1914 in only one single locality on the River 

 Kounia. This insect has been completely destroyed' by repeated spra^dngs 

 begun in 1908 under instructions issued by the Bureau, 1914 being the last 

 3'ear in which the treatment was used. In addition to this method of deal- 

 ing with Pachyiylus experiments have been made using baits of bran and 

 treacle poisoned with potassium arsenite. These experiments have given 

 splendid results. Besides this two sprayers have been tested: a horse drawn 

 machine and a knapsack spra3'er. The latter has been found to be the more , 

 convenient for the migratory cricket. 



Observations u])on harmful in.sects have been made by the .staff of 

 the Bureau during their tours, and at two places in the district temporary 

 laboratories have been equipped to the same end; thus a great number of 



