Arthropod pests
Aphids
Sap-feeding insects that often cluster on tender growth and leaf undersides. Honeydew, cast skins, and colonies are stronger evidence than leaf curl alone.
What to look for
- Clusters of soft-bodied insects on stems, petioles, undersides, and growing tips
- Sticky honeydew and sometimes secondary sooty growth
- White cast skins near colonies
- Distorted or slowed young growth under heavier feeding
Important look-alikes
- Root aphids on above-ground surfaces
- Whitefly nymphs
- Non-pest debris or shed plant tissue
How to confirm
- Use magnification to inspect body shape and cornicles when visible
- Check both winged and wingless forms
- Inspect roots if root aphids are a possibility
Management principles
- Treat colonies early and monitor new growth
- Use compatible biological, physical, and other controls as part of an integrated program
- Address ant activity where it protects aphids
Prevention
- Quarantine new plants
- Remove alternate host weeds
- Inspect propagation stock
- Maintain clean work flow between rooms
Visual study guide
- Winged and wingless aphid plate
- Honeydew and cast-skin close-up
- Aphid versus whitefly comparison
- Scouting locations diagram