Ma. Morris et al., OVERWINTERING AND EFFECTS OF AUTUMN HABITAT MANIPULATION AND CARBOFURAN ON NEOSEIULUS-FALLACIS AND TETRANYCHUS-URTICAE IN PEPPERMINT, Experimental & applied acarology, 20(5), 1996, pp. 249-257
The percentages of Neoseiulus fallacis (Carman) in four subhabitats of
peppermint fields in November were 37% on dead leaves, 45% in debris
below dead leaves, 3% in hollow stems and 15% on live foliage. in Dece
mber, the percentages were 36, 39, 7 and 18%, respectively, for these
same sites. The values were 40, 37, 18 and 5% and 6, 80, 14 and 0% for
January and February, respectively. By April, 95% of all predators we
re on new foliage feeding on Tetranychus urticae Koch, while the rest
were still in debris. Augmenting plots with debris increased overwinte
ring survival of N. fallacis compared to the natural condition while r
emoval of debris decreased it. An autumn carbofuran (Furadan 4F) treat
ment completely eliminated overwintering N. fallacis, thus leading to
outbreaks of T. urticae the following spring. The results of these ove
rwintering studies are discussed in relation to improved biological co
ntrol and spider mite management.