The Miridae (Hemiptera: Heteroptera) associated with noble fir, Abies procera Rehd.

The Miridae, or plant bugs, associated with noble fir, Abiesprocera Rehd., are discussed. Thirty six species of the Miridae werecollected from noble fir. Twenty five of these species are consideredonly "visitors" to noble fir. The study does not deal with thesespecies. Noble fir is a host of the eleven other species: Deraeocoris incertus Knight, Deraeocoris piceicola Knight, Dichrooscytus sp. A,Orthotylus sp. A, Paradacerla formicina (Parshley), Phytocoris neglectus Knight, Phytocoris sp. A, Pinalitus solivagus (Van Duzee), Plagiognathus sp. A and Psallus spp. A and B. Fifth instar larvae and the adults ofthese eleven species were examined and described.
The plant bugs were collected from the noble fir foliage everyseven to fourteen days from early May to mid-October, 1979 from
Marys Peak in the Oregon Coast Range and the H.J. Andrews ExperimentalForest in the Oregon Cascade Mountains. Distributional data were addedfrom collecting trips in Oregon on Grass Mountain and around Mt. Hoodand in Washington state at White Pass and Stevens Pass.
The larvae and adults of the eleven noble fir mirid species wereobserved in a growth chamber. Feeding observations were recorded foreight species. The larvae and adults were examined for external signsof insect parasitism. Sticky traps placed on the boles of noble firtrees on Marys Peak collected very few mirids, suggesting that the
mirids remain on the foliage and branches. Collections were madefrom three noble fir stands of increasing age in the Andrews Forest.All mirid species associated with the fir were present once the standwas 15-18 years old. The degree of host specificity is discussed forthe eleven species.
Eight species were collected regularly on noble fir from MarysPeak and ten from the Andrews Forest. Mirids were more abundant onMarys Peak than in the Andrews Forest. Possible causal factors arediscussed. The periods of occurrence of the larvae and adults of theeleven species are graphed. The larvae and adults of five mirid speciesappeared approximately five to seven days earlier on Marys Peak than inthe Andrews Forest. The adults of two other species appeared earlierin the Andrews Forest and the periods of occurrence of the remainingfour species differed little between the two areas. The two speciesof Deraeocoris occurred concurrently while the two species ofPhytocoris or Psallus were nearly temporally isolated from each otheron noble fir. Adult males were collected earlier in the season thanfemales and only females were seen late in the collecting season forseven species.