Includes asparagus aphid (Brachycorynella asparagi)
Pest description and crop damage Aphids feed on the fern and severely stunt growth. On mature fern, injury is a "tufting" of shoot growth beyond the point of injury. New shoots emerging from a plant with a heavy aphid infestation have shortened internodes and very small cladophylls, which produce a very dense clump of fern growth. Damage appears greatest to young plants. Nurseries with ferns infested in summer or fall may have 90 to 100% crown mortality the following spring. Mature stands may show loss of vigor and production.
Biology and life history
Asparagus aphid is somewhat unusual in that it spends its entire life cycle on asparagus. It overwinters in the egg stage on the foliage. Eggs hatch in early spring to produce wingless "stem mothers" which produce repeated generations of winged and wingless females throughout the spring and summer. In the fall sexual forms are produced and overwintering eggs are laid.
Management-chemical control: HOME USE
Apply to both tops and undersides of leaves.
- superior-type oil-Effective on any overwintering eggs found on plant debris. Some formulations are OMRI-listed for organic use.
- azadirachtin (neem extract)-Some formulations are OMRI-listed for organic use.
- insecticidal soap-May require several applications. Some formulations are OMRI-listed for organic use.
- kaolin-Applied as a spray to foliage and stems it acts as a repellent to some insect pests. Some formulations are OMRI-listed for organic use.
- plant-derived essential oils (peppermint, rosemary oil, etc.)-Some formulations are OMRI-listed for organic use.
- pyrethrins (often combined with other ingredients)-Some formulations are OMRI-listed for organic use.
Management-chemical control: COMMERCIAL USE
- acetamiprid (Assail 30 SG) at 0.047 to 0.1 lb ai/a. PHI 1 day. REI 12 hr. Retreatment interval 10 days. Do not exceed 0.2 lb ai/a per season. Limit 2 treatments.
- Beauveria bassiana (Mycotrol ESO) at 0.25 to 1 quart/a. PHI 0 days. REI 4 hr. OMRI-listed for organic use.
- chlorpyrifos (Warhawk, Lorsban Advanced) at 0.45 to 1 lb ai/a. PHI 1 day. REI 24 hr. Do not exceed one preharvest and two postharvest applications per year. RESTRICTED USE IN OREGON.
- Chromobacterium subtsugae (Grandevo) at 0.6 to 0.9 lb ai/a per 100 gal. PHI 0 days. REI 4 hr. Some formulations are OMRI-listed for organic use.
- dimethoate (Dimethoate 4E) at 0.5 lb ai/a following harvest. PHI 180 days. REI 48 hr. Retreatment interval 14 days. Do not exceed 1 lb ai per year.
- insecticidal soap (M-Pede) at 1 to 2% v/v solution. Potassium salts of fatty acids. See label for gal/a. PHI 0 days. REI 12 hr. Some formulations are OMRI-listed for organic use.
- malathion (Fyfanon 8) at 1 to 1.25 lb ai/a. PHI 1 day. REI 12 hr. Apply by air or ground. Do not exceed 2 treatment per season. Retreatment interval 7 days.
- pymetrozine (Fulfill) at 0.086 lb ai/a. PHI 170 days. REI 12 hr. Retreatment interval 30 days. Do not exceed 0.5 lb ai/a per season.