Urophora cardui
Adults are 4-5 mm and have large zebra striped wings.
Puccinia punctiformis
P. punctiformis is a naturalized fungus infecting Canada thistle.
Oberea erythrocephala
Adults are long and slender (10-12 mm) with long black antennae, red heads, and grey bodies.
Mecinus janthiniformis
Adult M. janthiniformis emerge from stems in May, and reproduce until late June.
Jaapiella invannikovi
Gall flies are very small and look similar to a tiny mosquito.
Hylobius transversovittatus
Adults emerge in late summer and live for up to 3 years.
Hadroplontus litura
Adults are small, brown weevils 3-4 mm long with a rounded body.
Galerucella spp.
Adults emerge from soil in April and June. Adults are 3-5 mm long and orange with brown stripes along the wings.
Eustenopus villosus
Adults emerge from soil in late May and are present through August. They are hairy and brown with white stripes.