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Abstract
Beardtongue (Penstemon Schmidel [Scrophulariaceae)) seeds are often produced without apparent damage from pests, but several species of native insects can adversely impact seed production fields. Tarnished plant bug (Lygus lineolaris (Palisot)) and western plant bug (Lygus hesperus Knight [Hemiptera: Miridae]), penstemon weevil (Hesperobaris sp. Casey [Coleoptera: Curculionidae]), penstemon clearwing moth (Penstemonia spp. [Lepidoptera: Sesiidae)), and ebony bug Corimelaena extenso Uhler [Hemiptera: Thyreocoridae)) have all been recorded as pests in penstemon seed production fields in the western US.
Citation
Hammon, Robert; Franklin, Melissa. 2012. Some insects affecting Penstemon seed production. Native Plants Journal. 13(2): 107-111.