A study of the host range and distribution of ticks and chiggers
(Acari) was undertaken in two contrasting forested areas of western
Oregon. Acarines were sampled from host mammals which were
trapped along line transects laid out in both areas, each consisting of
18 stations 50 feet apart. Hosts were...
The communicative behavior of five species and subspecies of
Tropisternus Solier (Coleoptera: Hydrophilidae) was studied. These
aquatic beetles have stress and calling chirps (both sexes), a second
male calling signal (one species), a single male courtship sound
(usually), a male copulatory sound, and a female aggressive rejection
buzz (three species)....
The western cherry fruit fly, Rhagoletis indifferens
Curran, was studied to determine the suitability of the
sterile insect technique for its control. To obtain
insect material, field collection of maggots is preferred
to sifting of soil or rearing on artificial diet.
The western cherry fruit fly is strictly univoltine;
only...
The purpose of this study was to examine various host and microclimatic influences affecting the survival and development of the flatheaded fir borer, Melanophila drummondi (Kirby) in Douglas fir, Pseudotsuga menziesii (Mirbel) Franco residues. It also expands current knowledge of the biology, bionomics, life history, ecology, and biotic potential for...
Prothoracicotropic hormone has been partially purified
from whole heads of tobacco hornworm larvae, Manduca sexta.
Activity was followed with a larval bioassay. Activity was
purified 4400 fold from crude extracts. The hormone was
found to be a heat-stable polypeptide with an approximate
molecular weight of 25,000 Daltons. The hormone has...
Aggregation and species association of 9 species of phytophagous and
predaceous mites were studied for 6 yr in an orchard with 100, 2 m tall 'Red
Delicious' apple trees. To quantify aggregation, a method was developed that is
powerful, and easily interpreted. It relates the proportion of habitat occupied to...