Insect Control

NOTE:  For the insecticides listed below, one product trade name and formulation is provided for each active ingredient (common name) as an example of rates, days to harvest (dh), REI, and special instructions. In many cases there are other products available with the same active ingredient. Please see Table 20 and Alphabetical Listing by Trade Name for more information on products with the same active ingredients.

Asparagus Aphids

Asparagus aphids are small, oval, green to gray aphids that may be covered in a waxy secretion. Male and female adults are produced in September and October and will mate and lay eggs on the lower portion of the ferns. Eggs hatch in the spring, go through 4 nymphal instars and then develop into stem mothers, capable of producing up to 55 live female nymphs within 20 days. There are many generations each season. Aphid feeding causes a shortening of the internodes and a rosetting or brush-like appearance of the foliage, especially near the tips of the lower branches. High aphid populations will reduce plant vigor and yield or kill seedlings. A combination of infestations and cold winters can kill even full size crowns within two years. Watch for abnormal plant growth on the lower portion of the fern. A combination of removing dead ferns during the fall or winter and spring tillage will usually control this pest. There are many natural enemies that help keep the aphid populations in check during the season including; lady beetles, lacewings, predatory midges, flower fly larvae, the Braconid wasp, Diaeretiella rapea, and parasitic fungi. Treating the ferns twice, about 10 days apart, with a systemic insecticide (i.e. dimethoate) will also provide effective control.

dimethoate (Dimethoate 4EC): 1 pt/A (180 dh, REI 48h, Group 1B). Apply after last harvest.

malathion (Malathion 57EC): 1 1/2 to 2 pt/A (1 dh, REI 12h, Group 1B).

pymetrozine (Fulfill): 2.75 oz/A (170 dh, REI 12h, Group 9A). Apply to ferns after harvest. Thorough spray coverage of plant foliage is essential for optimum control.

pyrethrin (PyGanic EC5.0): 4.5 to 18 oz/A (0 dh, REI 12h, Group 3A). OMRI listed.

pyrethrins + piperonyl butoxide (Pyrenone): 1 tsp/gal, or 1 to12 oz/A (0 dh, REI 12h, Group 3A).

Asparagus Miner

This pest can vector Fusarium spp. (asparagus decline). However, no material is available for controlling this pest. It is present from mid-May to late June and early August to late September. Jersey Giant seems to be more tolerant to asparagus decline than other varieties.

Cutworms

Caterpillars hide under the soil surface adjacent to the plant stem during the day and feed after dark. Crooks (misshaped spears) are often caused by cutworms injuring tips at or just below the soil surface or feeding on the sides of young spears. For best results, make application between midnight and dawn while cutworms are feeding above ground. Synthetic pyrethroids (group 3A) may work best during cool weather in May. See cutworms in the Pepper and Tomato (Outdoor) sections for more information on the black and variegated cutworms.

carbaryl (Sevin XLR PLUS): 1 to 2 qt/A prior to fern growth; 2 to 4 qt/A on ferns (1 dh, REI 12h, Group 1A). Limit of 3 pre-harvest and a total of 5 applications.

chlorpyrifos (Lorsban 75WG): 1.33 lb/A (1 dh, REI 24h, Group 1B). Limit of 1 pre-harvest and 2 post-harvest applications. Apply when soil is moist and in the evening when cutworms are becoming active.

methomyl (Lannate* LV): 1-1/2 to 3 pt/A (1 dh, REI 48h, Group 1A). Concentrate spray over row. May obtain better results with high gallonage (80 to 100 gal/A).

permethrin (Pounce* 25WP): 3.2 to 6.4 oz/A (1 dh, REI 12h, Group 3A).

Asparagus Beetle/Japanese Beetle

The common and spotted asparagus beetles are less than 3/8” long, overwinter as adults in protected areas along fields, feed on spears and ferns, pupate in the soil and have 2 to 3 generations per year. The common asparagus beetle (CAB) has a bluish-black body with cream-colored, square or rectangular spots, while the spotted asparagus beetle (SAB) is tan to orange with 12 round, black spots. Adult feeding on spears or the presence of eggs can render the crop unmarketable. Grey CAB larvae may cause severe defoliation of ferns and decline of the planting, while yellow or orange SAB larvae only feed on berries. Scout for adults and eggs on sunny afternoons. Treat spears if >10% of the plants are infested with beetles or 1 to 2% have eggs or damage. Treat ferns if 50 to 75% are infested. If possible spot spray along edges of planting where overwintering adults colonize the field and/or band insecticide over the row to help spare natural enemies. Use selective insecticides on ferns. During harvest, snap or cut sprears colse to the soil surface daily and eliminate volunteer plants or treat them with an insecticide to use them as a trap crop. Disk old ferns lightly in the fall and clean areas around planting of debris to reduce overwintering populations. Eliminating female plants, and thus berries, can reduce or eliminate SAB populations.

carbaryl (Sevin XLR PLUS): 1 to 2 qt/A prior to fern growth or 2 to 4 qt/A on ferns after harvest (1 dh, REI 12h, Group 1A). Limit of 3 pre-harvest and a total of 5 applications.

chlorpyrifos (Lorsban 75WG): 1.33 lb/A (1 dh, REI 24h, Group 1B). Apply during the fern stage.

dimethoate (Dimethoate 4EC): 1 pt/A (180 dh, REI 48h, Group 1B). Apply after last harvest.

kaolin (Surround WP): 12 1/2 to 25 lb/A or 0.25 to 0.5 lb/gal (0 dh, REI 4h). Suppression and repellence only. Product residue may need to be washed off if applied to spears during harvest. Follow label instructions for mixing. Generally compatible as a tank mix with other insecticides. OMRI listed.

malathion (Malathion 57EC): 1 1/2 to 2 pt/A (1 dh, REI 12h, Group 1B). Asparagus beetle only.

methomyl (Lannate* LV): 1 1/2 to 3 pt/A (1 dh, REI 48h, Group 1A). Not for Japanese beetle.

permethrin (Pounce* 25WP): 3.2 to 6.4 oz/A (1 dh, REI 12h, Group 3A). For Japanese beetle control use high rate.

pyrethrin (PyGanic EC5.0): 4.5 to 18 oz/A (0 dh, REI 12h, Group 3A). OMRI listed.

pyrethrins + piperonyl butoxide (Pyrenone): 1 tsp/gal or 1 to 12 oz/A (0 dh, REI 12h, Group 3A).

spinetoram (Radiant SC): 4 to 8 oz/A (60 dh, REI 4h,Group 5). Post-harvest protection of ferns from asparagus beetle only. Not for Japanese beetle.

spinosad (Entrust): 1.25 to 2 oz/A (60 dh, REI 4h, Group 5). Post-harvest protection of ferns from asparagus beetle. Not for Japanese beetle. OMRI listed.