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Showing 1 to 7 of 7 for “"Musk Thistle"”.
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A Comparison of the Viability of Thistle Weevils From Fire Ant Suppressed Site to Weevils From a Site Where Fire Ants Were Not Suppressed
<p>The thistle weevil, <em>Rhinocyllus conicus</em>, was introduced to the United States as an agent of biological control for another non-native species, the musk thistle,<em> Carduus nutans</em>. Musk thistle are noxious weeds of pastures which reduce forage for grazing livestock. A high weevil …
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Impact of Rhinocyllus conicus Froelich (Coleoptera:Curculioniadae) on the reproduction of Carduus thistles in Virginia
Musk thistle (Carduus nutans) seed production from early developing (terminal and first lateral) heads was reduced by 10% in 1973 and 75% in 1974 due to larval feeding of Rhinocyllus conicus. This was caused by heavy infestation of the early heads (45% in 1973, 70% in 1974) with a subsequent 5-fold …
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An Evaluation of a Low-Cost UAV Approach to Noxious Weed Mapping
… on foot method. Two noxious weeds were studied: musk thistle (Carduus nutans) and dalmation toadflax (Linaria dalmatica). The musk thistle was visually identifiable in the imagery but the dalmation toadflax was confused with yellow sweet clover (Melilotus officinalis). It was found that after the …
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Interactions between the rust fungus Puccinia carduorum Jacky and the musk thistle herbivores Trichosirocalus horridus (Panzer), Rhinocyllus conicus Froelich (Curculionidae: Coleoptera), and Cassida rubiginosa Muller (Coleoptera; Chrysomelidae)
… Müller and their combined impact on must thistle, Carduus thoermeri Weinmann were studied.
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Field biology and mortality factors affecting Cassida rubiginosa Müller (Coleoptera: Chrysomelidae), a biological control agent of Canada thistle (Cirsium arvense (L.) Scop.)
… average of 27.4 ± 1.7 days when reared on Canada thistle and 28.5 ± 2.1 days on an alternate host, musk thistle. Mortality due to incomplete development totaled 52.5% for immatures reared on Canada thistle and 79.0% for immatures reared on musk thistle. Mean survival from egg to adult of beetles …
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Integrated control of Carduus thistles and ecological studies on Rhinocyllus conicus Froelich and Ceuthorhynchidius horridus (Panzer)
… and integrated control program for Carduus thistles was developed using the biological control agents Rhinocyllus conicus Froelich and Ceuthorhynchidius horridus (Panzer) and the herbicide 2,4-Dichlorophenoxyacetic acid (2,4-D). Field studies on the development of Ceuthorhynchidius horridus …
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Biological studies of Rhinocyllus conicus, Carduus thoermeri and a model of the interaction between these two species
… was found to overwinter with lowest mortality on musk thistle rosettes; mortality was 73.6% in 1981, higher than previously reported but possibly more representative of field conditions. No overwintering mortality was observed for established rosettes of C. thoermeri. Studies of seed dispersal of …