WSU Tree Fruit

Cluster 6 – Peshastin


Each week, 10 leaves are taken from the lower and upper canopy of 10 trees in each plot for a total of about 100 leaves. Samples are run through a brushing machine and the insects that fall off are counted. In spring, the focus is on fruit spur leaves, where the first psylla nymphs are concentrated. In summer, both spur leaves and new shoots are sampled.  Leaf sampling began the week of May 14.

Beat Trays

30 limbs are sampled with a beat tray at each plot. Psylla adults and natural enemies are counted. Natural enemies include: predatory bugs (Deraeocoris, Campylomma, minute pirate bugs, damsel bugs, big-eyed bugs), Trechnites wasps, earwigs, lacewings, ladybeetles, and spiders.


There are three types of sticky card traps at each plot which collect flying adult insects. Each trap has 4 replicates.

1) Green lacewing, Chrysoperla plorabunda species (yellow card with AMP lure).
2) Green lacewing, Chrysopa nigricornis species (white card with squalene lure).
3) Campylomma bugs (yellow card with Scentry sex pheromone lure).

Trechnites wasps found on yellow sticky cards are also counted.

The graph below shows the sum of all natural enemies caught on sticky cards. This would include adults of both species of green lacewing, Campylomma bugs, Trechnites wasps, brown lacewings, Deraeocoris bugs, and ladybeetles.

The graph below shows the total number of Trechnites wasps collected from eight yellow sticky cards.

The graph below shows the sum total of both green lacewing species collected on eight sticky cards.

The graph below shows the total number of Campylomma bugs collected on 4 sticky cards.

This project was funded in part by a grant from WSDA Specialty Crop Block Grant K1986.