Ds. Volenberg et al., Biological control of yellow toadflax (Linaria vulgaris) by Eteobalea serratella in peppermint (Mentha piperita), WEED SCI, 47(2), 1999, pp. 226-232
Yellow toadflax is an introduced ornamental perennial that has become a ser
ious weed in Wisconsin peppermint production. Glyphosate is the only labele
d herbicide that controls yellow toadflax in peppermint. Other control stra
tegies, either mechanical or cultural, have little effect on the weed in so
lid stands of peppermint. Previous research has suggested chat the root min
ing moth Eteobalea serratella Tr. (Lepidoptera: Cosmopterigidae) may provid
e effective biological control of yellow toadflax. Therefore, experiments w
ere conducted to determine the host specificity of E. serratella and to qua
ntify E, serratella root mining of yellow toadflax. In larval and adult no-
choice tests, E. serratella attacked only yellow toadflax. Other plant spec
ies collected from E. serratella's natural range were not attacked, neither
those closely related to yellow toadflax in the family Scrophulariaceae, n
or those closely related to peppermint in the family Labiatae. Root mining
by E. serratella reduced root biomass an average of 20% compared to nontrea
ted plants, Peppermint competition alone or in conjunction with root mining
by E. serratella reduced root biomass 52 and 65%, respectively, compared t
o nontreated plants under noncompetitive conditions. E. serratella is host
specific for yellow toadflax and demonstrates potential as a biological con
trol agent by contributing to the reduced competitive ability of yellow toa
dflax in peppermint.