FIELD: agricultural biology. SUBSTANCE: method involves taking measurement of mass of spleen of females caught in winter crop in the fall tillering stage. Then account is taken of percentage of individuals in which this value is equal to or exceeds 0.55 g/% . Populations showing 60% or higher percentages are in the massive propagation phase, and they are quite harmful, and those showing less than 35% are in the decline phase and they are less harmful. In the range of values from 35% to 60% the population cycle phase is identified with regard for the previous year results. The population is in its phase when this value exceeds that of the previous year, and with the value lower than that of the previous year the population is on a rise. In the latter case a growth in harmfulness is to be expected. EFFECT: simpler and more accurate method. 2 cl, 1 tbl
