Express method of accounting and forecasting brown-tail moth (Euproktis chrisorrhoea l.) in forest and garden plantations
The biological peculiarities of brown-tail moth, a dangerous pest of many tree and garden plantings, were studied in order to develop a rapid method for obtaining sufficiently fast and reliable accounting and forecasting data. A comparative description of the existing methods of accounting of brown-tail moth in forest plantations and in garden ones has been carried out. It has been established that the accounting methods adopted in production are devoid of statistical justification and data on the size and number of accounting units. It is shown that the most informative indicator for obtaining data on the population of stands is the development of phytophage at the caterpillar phase in winter nests. Mass counts of winter nests with a simultaneous estimate of the number of caterpillars in them and the degree of nibbling of plantations made it possible to identify the relationship between these values. Tables for quick determination of the required sample size with three levels of accuracy are developed. A table establishing the number of pest larvae depending on the size of wintering nests has been developed. A model that allows predicting the degree of expected damage to plantings by a pest has been obtained.