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Beginner

Scientific Names
Deraeocoris spp., Hyaliodes vitripennis (Say), Campylomma verbasci (Meyer)

Identification
C. verbasci (mullein bug)
Eggs:

• 0.8 mm long.
• White.
• Flask-shaped.

Nymphs: 

• Five nymphal instars.
• 0.5-2.5 mm long, yellow to green, with a pointed head and red eyes. 
• Third instar nymphs have spots on their legs, which carry through to the adult stage.  

Adult:

• 3 mm long.
• Oval.
• Light green to tan in colour.
• Antennae are four segmented and prominent. 
• Hind legs have black spots and are spine covered. 

Deraeocoris spp.
Eggs:

• Elongate.
• Cream coloured.
• Laid in leaf axils or leaf mid-vein.

Nymphs:

• The nymphs of one of the most common species, D. nebulosus, pale grey with faint red marking on the legs and abdomen.

Adults:

• 4-7 mm.
• Stout.
• Light to dark-reddish brown or black markings.

H. vitripennis
Eggs:

• Elongate.
• Cream coloured.
• Laid singly or in small groups under bark of small twigs.

Nymphs:

• N/A

Adults:

• 4-5 mm in length.
• Long legs and partially transparent wings.

Often Confused With

• Aphids - Aphids have cornicles or tail pipes at the tip of the abdomen, which plant bug nymphs lack, and are slow moving.
• White apple leafhoppers - White apple leafhoppers have a more elongated body and short antennae.  The wings of leafhopper adults are held roof-like over the body.  White apple leafhoppers, adults and nymphs, lack the dark spots on the legs observed in mullein bug adults and late instar nymphs.
• Tarnished plant bug - Tarnished plant bugs belong to the same family as the predatory plant bugs described in this section. Adult tarnished plant bugs, the life stage most commonly observed in the apple canopy, are relatively large (6-7 mm), dark or light in colour (depending on the generation), and have a distinct Y on their back, behind the head. 

Interaction With Host
Plant bugs may be phytophagous (plant feeding), predatory or both.  In most cases, damage caused by predatory plant bugs is of limited no economic importance.

One of the more common species found in orchards is the mullein bug, C. verbasci. Although mullein bug is considered a pest of apple for two weeks pre- and post-bloom, after this time it becomes an important predator, feeding on mites and aphids found in apple orchards throughout the summer.

Deraeocoris spp. and H. vitripennis also feed on phytophagous mites and aphids.  Deraeocoris spp. will also attack small caterpillar larvae.  Adult H. vitripennis are also phytophagous and will pierce leaf veins and imbibe sap, though they cause no economic damage.

Period of Activity
May through August. There may be one or more generations per year.

Insects Attacked
Mites, aphids, caterpillars, leafhoppers, other soft-bodied insects.

Monitoring and Management
Mullein bugs are often found in terminals and during tapping in regular orchard monitoring.

Advanced

Scientific Names
Deraeocoris spp., Hyaliodes vitripennis (Say), Campylomma verbasci (Meyer).

Identification

• C. verbasci (mullein bug)
  Eggs: 0.8 mm long, white and flask shaped.
  Nymphs:  Mullein bugs develop through five nymphal instars to adults. Nymphs are 0.5-2.5 mm long, yellow to green, with a pointed head and red eyes.  Third instar nymphs have spots on their legs, which carry through to the adult stage.  
  Adults: Adult mullein bugs are 3 mm long, oval and light green to tan in colour. Antennae are four segmented and prominent.  Hind legs have black spots and are spine covered. 
  

• Deraeocoris spp.
  Eggs: Elongate, cream coloured, laid in leaf axils or leaf mid-vein.
  Nymphs: The nymphs of one of the most common species, D. nebulosus, pale grey with faint red marking on the legs and abdomen.  They are widely distributed geographically in Canada and the US, and are found in numerous tree crops and natural settings.
  Adults: Relatively large (4-7 mm), stout insects, with light to dark-reddish brown or black markings.

• H. vitripennis
  Eggs: Elongate, cream coloured, laid singly or in small groups under bark of small twigs.
  Nymphs: no description available.
  Adults: 4-5 mm in length with long legs and partially transparent wings (an unusual feature among plant bugs).

Often Confused With

• Aphids - Aphids have cornicles or tail pipes at the tip of the abdomen, which plant bug nymphs lack, and are slow moving.
• White apple leafhoppers - White apple leafhoppers have a more elongated body and short antennae.  The wings of leafhopper adults are held roof-like over the body.  White apple leafhoppers, adults and nymphs, lack the dark spots on the legs observed in mullein bug adults and late instar nymphs.
• Tarnished plant bug - Tarnished plant bugs belong to the same family as the predatory plant bugs described in this section. Adult tarnished plant bugs, the life stage most commonly observed in the apple canopy, are relatively large (6-7 mm), dark or light in colour (depending on the generation), and have a distinct Y on their back, behind the head. 

Interaction With Host
Plant bugs may be phytophagous (plant feeding), predatory or both.  Predatory plant bugs will often feed on plant sap to supplement their diets when pry are scarce as well as for moisture; few are strictly predators.  In most cases, damage caused by predatory plant bugs is of limited no economic importance, with the exception of mullein bugs early in the season 

One of the more common species found in orchards is the mullein bug, C. verbasci. Although mullein bug is considered a pest of apple for two weeks pre- and post-bloom, after this time it becomes an important predator, feeding on mites and aphids found in apple orchards throughout the summer. Mullein plants are an alternate host during the summer. Adult and nymphs are predaceous and feed primarily on European red mites and the green apple aphid, and may suppress populations of these pests in the early stages of infestation. They also feed on caterpillar larvae, leafhoppers and other soft-bodied insects. There are two to three generations each year in Ontario.  

Deraeocoris spp. and H. vitripennis also feed on phytophagous mites and aphids.  Deraeocoris spp. will also attack small caterpillar larvae.  Adult H. vitripennis are also phytophagous and will pierce leaf veins and imbibe sap, though they cause no economic damage.  Deraeocoris spp. and H. vitripennis nymphs are present in early June, with adults occurring from July through September, with one generation per year.

Period of Activity
Plant bugs overwinter as eggs protected in shoots, stems or leaf veins, or as adults in concealed places.  Depending on the species, they are active predators from May through August, and are considered the most important insect predators in Ontario apple orchards in mid to late summer.  There may be one or more generations per year.

Insects Attacked
Mites, aphids, caterpillars, leafhoppers, other soft-bodied insects.

Monitoring and Management
Mullein bugs are often found in terminals and during tapping in regular orchard monitoring.