SOIL INSECTS
SCARAB GRUBS
| Product Name (Active Ingredient) | Rate (Per Acre) | Requirements & Restrictions |
|---|---|---|
| Admire Pro | 7-14 fl oz | Imidacloprid products. Use soil drench treatment. Limit 2 apps/season but 1 app at higher rate is recommended. No aerial app, 30-day PHI. Best results are achieved when the compound is present just prior to egg hatch. Irrigate before and after application, but do not apply to saturated soil. Compound has very long soil residual. Highly toxic to bees; do not apply when pollinators are on bog. |
| Alias 4F Nuprid 4F Wrangler | 8-16 fl oz | |
| Malice Widow | 16-32 fl oz | |
| Summer flood | N/A | Remove winter flood, allow bog to dry out. Reflow mid-May and keep well flooded until mid-July. This will eliminate cranberry root grub and cranberry white grub larvae, as well as the crop for that year. Oriental beetle and Hoplia are also likely impacted. |
- Cranberry root grub (Lichnanthe vulpina) - grubs turn into low-flying beetle adults that look like bumblebees; they emerge from the soil during cranberry bloom and set. Males fly after dawn through mid-morning.
- Cranberry white grub (Phyllophoga anxia) - grubs turn into large-bodied "June bugs" as adult beetles and are active in the evening in May and June.
- Oriental beetle (Anomala orientalis) - small beetle (5/8 inch), vary greatly in color and pattern from light brown to black. Grubs develop over two years and are similar in appearance to small white grubs. An adult sex pheromone trap is available.
- Hoplia equina - adult beetles emerge synchronously from the soil during bloom in late afternoon. The small brown beetles are about 5/16 inch in size. The grubs develop over two years and are similar in appearance to small white grubs.
In the spring, look for grubs in both root layer and lower soil associated with areas of weak or dying vines. In grub-infested areas, try to avoid stress to vines such as high doses of Casoron and drought.
BLACK VINE WEEVIL AND STRAWBERRY ROOT WEEVIL
(Otiorhynchus sulcatus and Otiorhynchus ovatus)
- Nematodes - Availability limited—need to plan ahead and order well in advance of application. Target immatures (weevil grubs) in soil. Apply in early evening in May and/or September. Best results occur when soil temperatures are higher than 56°F. Irrigate before and after application.
- Fall Flood - Flood for 10-14 days as soon as possible after harvest. May also negatively impact vines. Warmer water enhances effectiveness.
- Winter Flood - If you can winter flood, populations should be less abundant.
In the spring, look for grubs in soil of areas with dying vines (often near bog edge) that may have an orange halo of vines around edges. Grubs feed on the bark of the vine. Adult beetles emerge in June; they must feed for about 4 weeks before egg-laying starts. Night sweep for weevils at edge of weevil-damaged areas, starting after dusk but before dew forms mid-June through July. Notched new foliage indicates adult feeding. Sweep when vines are dry. These pests are more abundant in bogs with no winter flooding or which have high spots.
CRANBERRY GIRDLER (Chrysoteuchia topiarius)
- Nematodes - Availability limited—need to plan ahead and order well in advance of application. Apply Nematodes 2 weeks after end of moth flight. Target immatures in soil.
- Fall Flood - Flood for 1 week, at end of September. Vines must be completely covered. These floods are best done when fruits have been removed. Research shows that this flood timing may negatively impact vine health.
- Regular Sanding - Sanding with 1-3 inches every 3rd year will reduce favorable girdler habitat.
In June through July, appearance of silvery-white moths with a "snout" on front of head that make short, jerky flights as you walk through the vines may signal a problem. If there is a history of girdler on your bog, use pheromone traps to time treatments. Be aware of girdler's true appearance; a very similar non-pest moth is also picked up in traps. A bad girdler infestation can exist even with low pheromone trap catches. Just below the trash line, look for old feeding damage that may be quite deep in the wood of the vine. Thorough trash flows are beneficial.
STRIPED COLASPIS (Colaspis costipennis)
| Product Name (Active Ingredient) | Rate (Per Acre) | Requirements & Restrictions |
|---|---|---|
| Admire Pro | 7-14 fl oz | Imidacloprid products. Soil drench targets immatures in soil. When adult beetles are picked up in net, application should be made to target larvae as eggs hatch. Compound has very long soil residual. No aerial application. Limit 2 apps/season, but 1 app at higher rate is recommended. Irrigate before and after application. Highly toxic to bees; apply after bloom in mid-late July. 30-day PHI. |
| Alias 4F Nuprid 4F Wrangler | 8-16 fl oz | |
| Malice Widow | 16-32 fl oz | |
| Diazinon 50 W | 4-6 lb | FIFRA 2(ee) recommendation targets adults. It is advisable to hold water for at least 3 days. 3 apps/season, 5-day REI, 7-day PHI, 14-day spray interval. |
| Diazinon AG 500 | 2-3 qt | |
| Diazinon AG 600 | 51-76.5 fl oz | |
| Sevin XLR Plus Carbaryl 4L | 1.5-2 qt | FIFRA 2(ee) recommendation targets adults. Do not apply when bed is in bloom. 5 apps/season, 7-day spray interval, 7-day PHI. *Beware, most handlers restrict with much longer PHI. |
Imidacloprid (Admire, Alias, etc.) applications should target hatching eggs in the soil. Diazinon and carbaryl (Sevin) sprays should target adults being picked up while sweep netting. Highly toxic to bees; advise beekeepers to remove or cover hives before application; these daytime applications will kill native bees foraging during bloom. The striped colaspis beetles are ca. 1/6” long and oblong-oval. Head area is metallic greenish-black and wings blackish, striped with yellow. Legs and antennae are yellow. Grubs in soil feed in root area, killing vines. Adult feeding results in distinct notching in top leaves of uprights, particularly in infested area. Prefers upland bogs.
SOUTHERN RED MITE (SRM) (Oligonychus ilicis)
| Product Name (Active Ingredient) | Rate (Per Acre) | Requirements & Restrictions |
|---|---|---|
| Nexter (pyridaben) | *3.5 - 7.0 oz/A by chemigation (4.4 – 10.67 oz/A by ground rig) | 2 apps/season. Ground and chemigation only – no aerial application. Hold water for 3 days after application. No flow-through bogs. 5 hours of drying time required. |
| Nexter SC (pyridaben) | *5.6 – 11.2 oz/A by chemigation (7.5 - 17.0 oz/A by ground rig) | |
| Late Water | N/A | Late water can eliminate mites in the year that the flood is held. In the second year following late water, mite pressure may still be low. See Late Water Section. |
Look for tiny red mites in sweep net and for red/orange streaks on rim of net or white card. Use a 10X magnifier to examine leaves to determine that mites are present; misidentifications frequently occur. Areas of discolored vines late in the season are often an indicator of mite infestation.