Classical biological control agents introduced into the Pacific Northwest for the management of weeds and the general role of each biocontrol species.
Biocontrol Agent |
Role |
Weed Species |
Aceria chondrillae (formerly Eriophyes chondrillae) |
bud gall mite |
Skeletonweed, rush (Chondrilla juncea) |
Aceria malherbae |
bud/leaf gall mite |
Bindweed, field (Convolvulus arvensis) |
Agapeta zoegana |
root-boring moth |
Knapweed, spotted (Centaurea stoebe; = C. stoebe ssp. micranthos) |
Agrilus hyperici |
root-boring beetle |
St. Johnswort (Hypericum perforatum) |
Aplocera plagiata |
defoliating moth |
St. Johnswort (Hypericum perforatum) |
Aphthona cyparissiae |
root/defoliating flea beetle |
Spurge, leafy (Euphorbia esula) |
Aphthona czwalinai |
root/defoliating flea beetle |
Spurge, leafy (Euphorbia esula) |
Aphthona flava |
root/defoliating flea beetle |
Spurge, leafy (Euphorbia esula) |
Aphthona lacertosa |
root/defoliating flea beetle |
Spurge, leafy (Euphorbia esula) |
Aphthona nigriscutis |
root/defoliating flea beetle |
Spurge, leafy (Euphorbia esula) |
Aulacidea acroptilonica |
gall wasp |
Knapweed, Russian (Rhaponticum repens; = Acroptilon repens) |
Bangasternus fausti |
seedhead weevil |
Knapweed, spotted (Centaurea stoebe; = C. stoebe ssp. micranthos); knapweed, diffuse (C. diffusa) |
Bangasternus orientalis |
seedhead weevil |
Starthistle, yellow (Centaurea solstitialis) |
Botanophila seneciella |
seedhead fly |
Ragwort, tansy (Senecio jacobaea; = Jacobaea vulgaris) |
Brachypterolus pulicarius |
flower beetle |
Toadflax, yellow (Linaria vulgaris); toadflax, Dalmatian (L. dalmatica) |
Bradyrrhoa gilveolella |
root-boring moth |
Skeletonweed, rush (Chondrilla juncea) |
Bruchidius villosus |
seed beetle |
Broom, Scotch (Cytisus scoparius); broom, French (Genista monspessulana) |
Calophasia lunula |
defoliating moth |
Toadflax, yellow (Linaria vulgaris); toadflax, Dalmatian (L. dalmatica) |
Chaetorellia acrolophi |
seedhead fly |
Knapweed, spotted (Centaurea stoebe; = C. stoebe ssp. micranthos) |
Chaetorellia australis |
seedhead fly |
Starthistle, yellow (Centaurea solstitialis) |
Cheilosia grossa (formerly C. corydon) |
stem fly |
Thistle, slenderflower (Carduus tenuiflorus); thistle, Italian (C. pycnocephalus) |
Chrysolina hyperici |
defoliating beetle |
St. Johnswort (Hypericum perforatum) |
Chrysolina quadrigemina |
defoliating beetle |
St. Johnswort (Hypericum perforatum) |
Cyphocleonus achates |
root-boring/gall weevil |
Knapweed, spotted (Centaurea stoebe; = C. stoebe ssp. micranthos); knapweed, diffuse (C. diffusa) |
Cystiphora schmidti |
stem/leaf gall midge |
Skeletonweed, rush (Chondrilla juncea) |
Diorhabda carinulata C (formerly D. elongata) |
leaf beetle |
Saltcedar (Tamarix ramosissima) |
Euhrychiopsis lecontei E |
stem weevil |
Watermilfoil, Eurasian (Myriophyllum spicatum) |
Eustenopus villosus |
seedhead weevil |
Starthistle, yellow (Centaurea solstitialis) |
Exapion fuscirostre |
seed weevil |
Broom, Scotch (Cytisus scoparius) |
Exapion ulicis |
seed weevil |
Gorse (Ulex europaeus) |
Galerucella calmariensis |
leaf beetle |
Loosestrife, purple (Lythrum salicaria) |
Galerucella pusilla |
leaf beetle |
Loosestrife, purple (Lythrum salicaria) |
Hadroplontus litura (formerly Ceutorhynchus litura) |
crown/root weevil |
Thistle, Canada (Cirsium arvense) |
Hyles euphorbiae |
defoliating moth |
Spurge, leafy (Euphorbia esula) |
Hylobius transversovittatus |
root-boring weevil |
Loosestrife, purple (Lythrum salicaria) |
Jaapiella ivannikovi |
shoot tip gall midge |
Knapweed, Russian (Rhaponticum repens; = Acroptilon repens) |
Larinus curtus D |
seedhead weevil |
Starthistle, yellow (Centaurea solstitialis) |
Larinus minutus |
seedhead weevil |
Knapweed, spotted (Centaurea stoebe; = C. stoebe ssp. micranthos); knapweed, meadow (C. x moncktonii; = C. jacea x nigra; = C. debeauxii; = C. pratensis); knapweed, diffuse (C. diffusa) |
Larinus obtusus |
seedhead weevil |
Knapweed, spotted (Centaurea stoebe; = C. stoebe ssp. micranthos); knapweed, meadow (C. x moncktonii; = C. jacea x nigra; = C. debeauxii; = C. pratensis) |
Leucoptera spartifoliella |
twig mining moth |
Broom, Scotch (Cytisus scoparius) |
Longitarsus jacobaeae |
root/defoliating flea beetle |
Ragwort, tansy (Senecio jacobaea; = Jacobaea vulgaris) |
Mecinus janthiniformis (formerly M. janthinus) |
stem-boring weevil (Dalmatian toadflax) |
Toadflax, Dalmatian (Linaria dalmatica) |
Mecinus janthinus |
stem-boring weevil (yellow toadflax) |
Toadflax, yellow (Linaria vulgaris) |
Metzneria paucipunctella |
seedhead moth |
Knapweed, spotted (Centaurea stoebe; = C. stoebe ssp. micranthos) |
Microlarinus lareynii |
seed weevil |
Puncturevine (Tribulus terrestris) |
Microlarinus lypriformis |
stem weevil |
Puncturevine (Tribulus terrestris) |
Nanophyes marmoratus |
flower bud weevil |
Loosestrife, purple (Lythrum salicaria) |
Oberea erythrocephala |
stem-boring beetle |
Spurge, leafy (Euphorbia esula) |
Phrydiuchus tau |
crown/root weevil |
Sage, Mediterranean (Salvia aethiopis) |
Pterolonche inspersa |
root-boring moth |
Knapweed, diffuse (Centaurea diffusa) |
Puccinia chondrillina |
rust fungus |
Skeletonweed, rush (Chondrilla juncea) |
Puccinia jaceae var. solstitialis |
rust fungus |
Starthistle, yellow (Centaurea solstitialis) |
Rhinocyllus conicus A |
seedhead weevil |
Thistle, slenderflower (Carduus tenuiflorus); thistle, plumeless (C. acanthoides); thistle, musk (C. nutans); thistle, milk (Silybum marianum); thistle, Italian (C. pycnocephalus); thistle, Canada (Cirsium arvense) |
Rhinusa antirrhini (formerly Gymnetron antirrhini) |
seedhead weevil |
Toadflax, yellow (Linaria vulgaris) |
Sphenoptera jugoslavica |
root-boring/gall beetle |
Knapweed, spotted (Centaurea stoebe; = C. stoebe ssp. micranthos); knapweed, diffuse (C. diffusa) |
Subanguina picridis |
stem/leaf gall nematode |
Knapweed, Russian (Rhaponticum repens; = Acroptilon repens) |
Terellia virens |
seedhead fly |
Knapweed, spotted (Centaurea stoebe; = C. stoebe ssp. micranthos) |
Tetranychus lintearius |
spider mite |
Gorse (Ulex europaeus) |
Trichosirocalus horridus A |
root/crown weevil |
Thistle, slenderflower (Carduus tenuiflorus); thistle, plumeless (C. acanthoides); thistle, musk (C. nutans); thistle, Italian (C. pycnocephalus) |
Tyria jacobaeae B |
defoliating moth |
Ragwort, tansy (Senecio jacobaea; = Jacobaea vulgaris) |
Tyta luctuosa |
defoliating moth |
Bindweed, field (Convolvulus arvensis) |
Urophora affinis |
seedhead gall fly |
Knapweed, spotted (Centaurea stoebe; = C. stoebe spp. micranthos); knapweed, diffuse (C. diffusa) |
Urophora cardui |
stem gall fly |
Thistle, Canada (Cirsium arvense) |
Urophora quadrifasciata |
seedhead gall fly |
Knapweed, spotted (Centaurea stoebe; = C. stoebe ssp. micranthos); knapweed, meadow (C. x moncktonii; = C. jacea x nigra; = C. debeauxii; = C. pratensis); knapweed, diffuse (C. diffusa) |
Urophora sirunaseva |
seedhead gall fly |
Starthistle, yellow (Centaurea solstitialis) |
Urophora stylata A |
seedhead gall fly |
Thistle, bull (Cirsium vulgare) |
A Rhinocyllus conicus and Trichosirocalus horridus are not recommended. They attack native thistles and interstate permits are suspended. B Tyria jacobaeae is not recommended east of the Cascades, particularly in Idaho. It attacks several native plant species. C Diorhabda carinulata (formerly D. elongata) interstate shipment permits have been suspended. D Larinus curtus may be infected with a disease that can reduce insect populations. It should not be redistributed to avoid spreading the disease to healthy L. curtus populations. E Euhrychiopsis lecontei is a native insect, and thus, not a classical biological control agent. The weevil is co-evolved with native milfoil, Myriophyllum sibiricum, but also attacks Eurasian watermilfoil, M. spicatum. It is naturally-occurring at many lakes in the Pacific Northwest and weevil releases often augment inadequate native populations. It is currently only available commercially. |