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Beginner

Scientific Names 
The most common species found in apple orchards are the minute pirate bug Orius insidiosus (Say) and the insidious flower bug Orius tristicolor (White)

Identification
Orius spp.
Eggs: 

• 0.55 mm long.
• Clear.
•  Deposited inside plant material and rarely seen.

Nymphs:

• 0.2-0.5 mm.
• Yellow-orange to brown.
• Teardrop-shaped and wingless.
• Fast-moving and often take refuge in developing leaves and flowers.
• Have piercing-sucking mouthparts used to subdue and feed on their prey.

Adults:

• Orius insidiosus adults are 3 mm long, oval with black and white wing patches.
• Fast-moving and often take refuge in developing leaves and flowers.
• Have piercing-sucking mouthparts used to subdue and feed on their prey.
• Anthocoris spp. adults are 3 mm long.

Often Confused With

• Mullein bug numphs - Mullein bug nymphs are yellow-green while those of Orius spp. and Anthocoris  spp. are reddish brown.

Interaction With Host
Orius spp. and Anthocoris spp. are common predators in numerous agricultural crops. Both adults and nymphs suck body fluids from their prey. When prey populations are low, they will feed on pollen and plant juices. Both immature and adult Orius spp. consume 30 or more spider mites/day. 

Period of Activity
Pink through harvest.

Insects Attacked
Adults and nymphs feed on aphids, spider mites, thrips, insect and mite eggs, and small caterpillars.  Anthocorids will occasionally probe plant tissue with their beaks, but this does not appear to cause damage.  They can inflict a painful bite on humans.

Monitoring and Management
O. insidiosus appears in orchards in mid April and remains active through to October.  Anthocoris spp. adults are first active in late April to early May and most abundant in late July and early August. They occur most frequently on the under surfaces of leaves, searching along the mid-ribs for prey. Crop consultants monitor for the presence of flower bugs by visual examination of terminals when monitoring for aphids.  Adults and nymphs can be monitored in orchards with beating trays.  Research suggests these insects appear to have developed a tolerance to some insecticides, such as azinphosmethyl, but they are very susceptible to pyrethroids.  For more information on toxicity of pesticides to beneficial insects refer to OMAFRA Publication 360, Fruit Production Recommendations.

Advanced

Scientific Name 
Although there are several different species of flower bugs found in Ontario orchards the most common are the minute pirate bug Orius insidiosus (Say) and the insidious flower bug Orius tristicolor (White)

Identification
The following is a description of Orius spp.

Eggs: Eggs are 0.5 mm long and clear. They are deposited inside plant material and are rarely seen.

Nymphs: Nymphs are 0.2-0.5 mm, yellow-orange to brown and teardrop-shaped and wingless. Both nymphs and adults are fast-moving and often take refuge in developing leaves and flowers.

Adults: Orius insidiosus adults are 3 mm long, oval with black and white wing patches. Both nymphs and adults have piercing-sucking mouthparts used to subdue and feed on their prey. Anthocoris spp. adults are 3 mm long.

Often Confused With

• Mullein bug nymphs - Mullein bug nymphs are yellow-green while those of Orius spp. and Anthocoris  spp. are reddish brown.

Interaction With Host
Orius spp. and Anthocoris spp. are common predators in numerous agricultural crops. They overwinter as adults both within and outside of the orchard. In the spring females lay eggs in leaves or buds.  There are 5 larval instars and two or more generations per year in Ontario Both adults and nymphs suck body fluids from their prey. When prey populations are low, they will feed on pollen and plant juices. Both immature and adult Orius spp. consume 30 or more spider mites/day.  Both adults and nymphs feed mainly on psyllids, as well as on aphids, other small insects, and phytophagous mites.  These tiny predators reproduce more rapidly than do most other common predaceous insects. They can develop from egg to adult in as little as 15 days. O. insidiosus has two or more generations per year in Ontario. 

Period of Activity
Pink through harvest.

Insects Attacked
Adults and nymphs feed on aphids, spider mites, thrips, insect and mite eggs, and small caterpillars. Anthocorids will occasionally probe plant tissue with their beaks, but this does not appear to cause damage. They can inflict a painful bite on humans.

Monitoring and Management
O. insidiosus appears in orchards in mid April and remains active through to October.  Anthocoris spp. adults are first active in late April to early May and most abundant in late July and early August. They occur most frequently on the under surfaces of leaves, searching along the midribs for prey. Crop consultants monitor for the presence of flower bugs by visual examination of terminals when monitoring for aphids.  Adults and nymphs can be monitored in orchards with beating trays.  Research suggests these insects appear to have developed a tolerance to some insecticides, such as azinphosmethyl, but they are very susceptible to pyrethroids.  For more information on toxicity of pesticides to beneficial insects refer to OMAFRA Publication 360, Fruit Production Recommendations.