Campylomma verbasci
Pest description and crop damage Campylomma bug is not native to the US, but has been present since the late 1800s. Adults are brownish-yellow and about 0.1 inch long, very mobile and active. Nymphs are small, green, and fast moving and about 0.1 inch long when mature. The mature nymphs resemble aphids in some ways but are far more active. Feeding by nymphs causes dimpling and distortion of fruit.
Biology and life history Campylomma bug females lay their overwintering eggs into crevices in the bark of the tree where the eggs lie dormant until spring. The eggs begin to hatch prior to bloom and developing nymphs can scar fruit with early feeding activity on the tiny maturing fruitlets. Campylomma bug remains on the tree host through the bloom period until late spring when they move to herbaceous host plants. Campylomma bug is known as mullein plant bug, after one of its preferred herbaceous hosts - the noxious weed common mullein. Weeds and crop plants such as potato, sugar beet, corn and small grains are also accepted herbaceous hosts. Campylomma bug feeds on the plant as well as preying on aphids and thrips while on the herbaceous host. Later in the season, adults move into to the orchard to mate and lay eggs. Other than the brief window around bloom when fruit damage can occur, campylomma bug is overwhelmingly a beneficial insect that helps manage aphids, mites, and psylla (important for pears) in the orchard. Monitoring populations early in the season is important for determining whether to apply treatments typically timed at prebloom or bloom (take precautions to protect pollinators). After this period, campylomma bug cannot damage fruit and serves as a beneficial insect. Operators may find that it is cost-effective to hand thin the fruit damaged in the early season.
Scouting and thresholds Nymphs and adults may be monitored by limb tapping from the pink stage through petal fall.
Management-cultural control
Early-blooming apple varieties may be most affected. Damaged fruit can be thinned.
Management-chemical control: HOME USE
There are no products specifically registered for control of campylomma bug in apple for home use.
Management-chemical control: COMMERCIAL USE
Stages 5-6: Pink spray
- acetamiprid (Assail 70WP) at 1.7 to 3.4 oz/A in up to 100 gal water per application. Do not apply when bees are active. Do not make more than four applications per year or exceed 13.5 oz/A per growing season. REI 12 hr. PHI 7 days. [Group 4A]
- esfenvalerate (Asana XL) at 4.8 to 14.5 oz/A in up to 100 gal water per application. REI 12 hr. PHI 21 days.
- thiamethoxam (Actara WDG) at 4.5 oz/A in a minimum of 50 gal water per application. Do not apply during bloom; highly toxic to bees. Do not exceed 16.5 oz/A per season. REI 12 hr. PHI 35 days. [Group 4A]