Adult fir engraver beetles were examined by serial paraffin sections and scanning electron microscopy. In both male and female beetles small cup-shaped pits covering the top and portions of the side of the head were consistently found to carry fungal spores. These pits usually contained a waxy looking material in which the spores were imbedded. The pits provide a mechanism for fungal transport and storage.

No abstract

If forest health is to be approached scientifically, it must be d e f i e d and meisured. Forest health is a condition of forest ecosvstems that sustains their com~lexitv while ~roviding for human neeis. We developed this broad detinitibn becake a wisely acceptable definition is lack in^, and forest health is a focal point in discussions of how to sustain forest ecosystems in the united States. Steps for measuring forest health are: (1) select a representative set of indicators for a particular ecosystem; (2) establish baseline data, such as a historical range of variability; (3) develop standards against which to compare current conditions; and (4) establish a monitoring program to assess current conditions and modify baseline data as new trends develop.

The balsam woolly adelgid (Adelges piceae) was introduced from Europe to northeastern North America in about 1900. In 1983, it was discovered infesting fir trees in Idaho. Since then, aerial and ground surveys have documented its spread in Idaho over an area of approximately 14,000 mi2 (8,960,000 ac). It now covers most of the central one-third of the state. Aerial surveys in 1997 and 1998 identified about 125,000 ac of host type with dead or damaged trees. Subalpine fir (Abies lasiocarpa) is a critical species in many high elevation areas. The effects of the balsam wooly adelgid on aesthetics, hydrology, and other ecological values can be very important. The adelgid is likely to continue its spread throughout subalpine fir forests of Idaho and neighboring states. West. J. Appl. For. 15(4):227-231,

Can. Ent. 109: 10.57-1062Ent. 109: 10.57- (1977. The effect of density on host-parasite interactions between Hypera postica (Gyllenhal) and Bathyplectes anurus (Thomson) was studied in a caged system in the laboratory. There was no significant relationship between proportion of hosts parasitized and host density. The frequency distribution of the parasite's eggs approximated the Poisson distribution in 83% of the cases. There was a quadratic relationship between number of superparasitized hosts and parasite density. However, no significant correlation between proportion superparasitized and host density was detected. The Nicholsonian area of discovery was inversely related to parasite density with a strong mutual interference constant of -,467.