Control of Chrysanthemum Stool Miner

Observations on the Biology and Control of the Chrysanthemum Stool Miner

“…It is not yet known what happens to this early emergence of stool miner since no damage to cuttings has been reported early in the season and no larvae have been found on chrysanthemums at this time of the year. Two specimens of Psila njgromaculata Strobl, were obtained from traps at Wellington in September 1955, and one of Psrla bicolor Mg, from a trap at Heswall in September 1956, The latter species has recently been described as causing damage to chrysanthemums in Scotland (Osborne, 1955), CONTROL Golightly and French (1957) showed that a root drench of 0'05 per cent dieldrin in early August and again in mid-September reduced the infestation of second generation larvae considerably; existing infestations in boxed stools could be reduced to a considerable extent by a root drench of 0-3 per cent schradan or O'l per cent demeton-methyl, Osborne (1958) showed that a root drench of 0'05 per cent aldrin, BHC or dieldrin applied within seven days of planting out in May gave good protection throughout the growing season.…”