102 . - FOR BETTER CROPS 



thinclilmg gets in its injurious work; but let wet weather follow 

 when a field is badly infested with these pests and various deadly- 

 fungus diseases appear and exterminate them for that season. 

 Under certain conditions the Hessian fly also has its parasitic 

 enemies which quietly and quickly reduce their numbers, thus 

 doing swiftly and silently, the task man labors more clumsily to 

 accomplish. 



Co-operation Among Farmers — Growing the same crop 

 continuously over large areas tends to increase the insect pests. 

 There should be co-operation among farmers in their efforts to 

 subdue these enemies. The care and forethought of one farmer 

 may be entirely undone by carelessness on adjoining farms. As 

 intensive farming becomes more and more a necessity, more 

 attention will be given to the extermination of insect enemies, 

 and communities will unite in their warfare against them. 



Rust in Wheat — Eust is sometimes more injurious to wheat 

 than its insect enemies. Years ago it was learned that certain 

 plants were largely responsible for the spread of rust on wheat. 

 The year book of the Department of Agriculture for 1904 gives 

 an account of the discovery that the spores of barberry rust will 

 spread to adjoining wheat fields; and so destructive is this rust 

 that laws were passed in some states requiring the destruction 

 of barberry hedges. By this measure that particular form of 

 rust was greatly reduced. A good many years before this was 

 published by the Department of Agriculture, this fact came under 

 my observation, and barberry bushes that were highly prized 

 were sacrificed. These bushes had been brought from the old 

 home in the east and were not only ornamental, but a tie 

 between the old home and the new. Continued outbreaks of 

 rust in wheat fields near these bushes led to the discovery 

 that they were the cause of the trouble. Several years later the 

 same rust appeared in a neighbor's fields and search brought to 

 light the fact that birds had carried seed to a woodlot some 

 distance from the original shrub, and these had grown into 

 bushes that were again spreading this destructive rust. A 

 peculiar fact about this rust on the barberry is that it does not 

 injure the barberry plant, but does greatly injure the wheat 

 plant, producing first a red rust on the blades and later a black 

 rust. The great epidemics appear as red rust. If the season is 

 moist the plants are overwhelmed by the rapid spread of this 

 disease. In climates where the red rust on the wheat plants 

 cannot withstand the winters but must be carried over on its 

 host, the barberry bush, it is only necessary to get rid of the 

 barberry bushes in order to eliminate its ravages, but where it 

 lives over winter in the fields, the wheat is more or less infected 

 each season. 



