Vegetables

Vegetable Insects - Joanne Whalen, Extension  IPM Specialist;   jwhalen@udel.edu

 

Cabbage.

We can still find economic levels of DBM and an occasional cabbage looper and imported cabbage worm in fall cabbage fields. The treatment threshold is 5% of the plants infested. Avaunt (3.5 oz/acre), a Bt, Proclaim (3 oz/acre), or Spintor (4-5 oz per acre) will provide control of all 3 species.  If cabbage looper and imported cabbage worm are the predominant species, a pyrethroid, Intrepid (8 oz/a) or Confirm (8 oz/acre) will also provide control.

 

Lima Beans.

Continue to scout fields for corn earworms until frost. A treatment is recommended for corn earworm if you find one worm per 6 foot of row.

 

Peppers.

Continue to spray peppers on a 5-7 day schedule for beet armyworm, corn borer, corn earworm, and fall armyworm. Also, continue to watch for aphids in fields where a continuous pyrethroid program was used. Actara, Assail, Fulfill, Lannate, or Provado will provide control. Be sure to check labels for days to harvest.

 

Snap Beans.

Sprays are still needed at the bud and pin stages on processing snap beans for corn borer control. A corn earworm material will also be needed at the pin spray for corn earworm.  Although corn borer and corn earworm catches have decreased, 1-2 sprays will still be needed between the pin spray and harvest. Since this can change quickly, be sure to check our website for the most recent trap catches and information on how to use this information to make a treatment decision in processing snap beans (http://www.udel.edu/IPM/traps/latestblt.html and our link to http://www.udel.edu/IPM/thresh/snapbeanecbthresh.html).  As soon as pin pods are present, fresh market beans should be sprayed on a 5 to 7-day schedule. Lannate, Capture, Mustang MAX or Warrior should be used.

 

Spinach.

We have seen an increase in webworm moth activity and egg laying. Small to moderate size garden and Hawaiian beet webworms can now be found. Although not as high as last season, we can also find beet armyworms in the mix. As soon as plants emerge, fields should be scouted for webworm and beet armyworm larvae. Controls should be applied when worms are small and before they have moved deep into the hearts of the plants. Also, remember that both insects can produce webbing on the plants. Confirm, Intrepid or Spintor will be needed for beet armyworm control. If webworms are the predominant species,  Ambush, Pounce, Confirm (6-8 oz/acre), Intrepid (8-10 oz/acre) or Spintor (4-8 oz/acre) should be used. Generally, at least 2 applications are needed to achieve control of webworms and beet armyworm.

 

Sweet Corn.

Any fresh market silking sweet corn should be sprayed on a 3-day schedule for the remainder of the season. Be sure to check our website for the most recent trap catches and information on how to use this information to make a treatment decision in fresh market sweet corn (http://www.udel.edu/IPM/traps/latestblt.html and http://www.udel.edu/IPM/thresh/silkspraythresh.html ).

 

 

UD IPM Black Light and Pheromone Trap Counts

Average Number of Moths per Night: September 19 to September 22, 2003

 

* Numbers can change quickly. For the most recent trap counts, access the website at (http://www.udel.edu/IPM/traps/latestblt.html) or call 1-800-345-7544 (in-state); 1-302-831-8851 (out-of-state). Counts are updated on Tuesday and Friday.

 

 

 

Vegetable Crop Diseases – Bob Mulrooney Extension Plant Pathologist; bobmul@udel.edu

 

Lima Beans.

Downy mildew, white mold, Pythium, and lima bean pod rot (Phytophthora capsici) continue to be seen in lima bean fields. Keep scouting fields. Obviously we have had ideal conditions especially for downy mildew. Since some of the infected varieties have been C-elite Select we are presuming that Race F is out there. Although we have listed Cypress susceptible to race F it does not develop as quickly or severely as it does on C- Elite Select when race F is present. If this is not your experience we would like to know about it. Preliminary data from our field plots indicate that Ridomil Gold/Copper is providing excellent control of downy mildew when applied preventatively under heavy disease pressure. Protectant sprays of Ridomil Gold/Copper and copper are recommended for downy mildew.

 

 

 

Stinger Labels For Some Vegetables and Fruits - Mark VanGessel, Extension Weed Specialist, mjv@udel.edu

 

DowAgroSciences has labeled Stinger for a number of vegetables and fruits grown in Delaware.  This includes turnip greens and roots, sweet corn, spinach, brassica leafy crops, and stone fruits.  Brassica leafy crops include broccoli, broccoli raab, Brussel sprouts, cabbage, cavalo broccoli, cauliflower, bok choy, Chinese cabbage, Chinese broccoli, Chinese mustard cabbage, Chinese cabbage, collards, kale, kohlrabi, mizuna, mustard greens, mustard spinach, rape greens.  All these uses are for postemergence broadleaf weed control.  Rates and number of applications allowed per crop vary so refer to specific labels.  Labels are available at www.cdms.net (click on US-Ag/Crop; type in Stinger in the search box; click on icon for label).  Spray additives are not required or recommended.  Control of common ragweed, galinsoga, chamomile, vetch, cocklebur, pineappleweed is good.  Fair to good control of Canada thistle and mugwort.  Nightshades are on the label, but we do not have much experience with these species.  Stinger will not control grass species.  Refer to the full Stinger label for precautions of crop rotations.

 

 

 

Field Crops

 

Field Crop Insects - Joanne Whalen, Extension  IPM Specialist;   jwhalen@udel.edu

 

Soybeans.

Corn earworm moth activity remains low and many pupating larvae have been triggered into diapause (overwintering stage), thus will not emerge as moths this fall. Double crop fields may still be susceptible until frost, particularly fields with flat pods or seeds just beginning to enlarge. Basically, once seeds are full sized and pods toughen up, they are no longer at risk. The treatment threshold for podworms is 3 per 25 sweeps in narrow fields and 5 per 25 sweeps in wide row fields (20 inches or greater). In addition, you should wait to treat until at least 1/3 of the populations is 1/2 -inch in size and you observe the first signs of pod-feeding.

 

Stored Grain.

The most important way to minimize insect problems in stored grain is the prevention of potential problems through good bin management. Before treating with a protectant insecticide, make sure that the bins are free of insect infested grain. Leftover grain should be removed from the bin, and the walls should be swept and vacuumed. All grain handling equipment including augers, combines, trucks and wagons should be thoroughly cleaned and grain residues removed before harvest. Residual bin sprays should be applied to all interior bin surface areas 2 to 3 weeks before new grain is placed in the bin. These treatments will kill insects that emerge from hiding places like cracks, crevices, and under floors. It will help to control insects crawling or flying in from the outside. Be sure to spray as many surfaces as possible, especially joints, seams, cracks, ledges, and corners. Sprays directed to the ceiling, walls and floors should be applied to the point of runoff. Use a coarse spray at a pressure of over 30 lbs. per square inch and aim for the cracks and crevices. Spray beneath the bin, its supports and a 6 ft. border around the outside foundation. Also, treat the outside surface, especially cracks and ledges near doors and fans. Materials available as residual bin sprays include Diacon II (methoprene- will not control adult insects), Malathion (may not provide control of Indian meal moth), Methoxychlor, Reldan 4E, Tempo, and Storcide.  After the bins are cleaned and treated, insecticides called grain protectants may also be applied to grain as it is moved into storage. Insecticides may be applied as a spray or dust to the grain as it is being augered into the bin. These products may also be applied as a surface treatment on registered commodities.  The following materials are labeled as grain protectants: Corn and Sorghum only - Acetellic; Wheat, Barley, Oats, Sorghum– Diacon II, Reldan (not for malting barley) and Storcide (cyfluthrin in the mix does not have CODEX MRLs so check with your grain handler if you plan to export).  If a grain protectant is not used, a surface insecticide should be used after all grain is placed in the bin. These treatments should be applied to the top 6-12 inches of grain and provide a barrier for migrating insects like Indian meal moth larvae. In order to provide effective control, all surface crusting and webbing should be removed prior to treatment. Bacillus thuringienesis (e.g.Dipel - Indian meal moth larvae only) or Insecto (diatomaceous earth) can also be used.

 

 

 

Field Crop Diseases – Bob Mulrooney Extension Plant Pathologist; bobmul@udel.edu

 

Soybeans. 

Septoria brown spot is increasing in severity on soybeans in some parts of the state and neighboring Maryland. Some have questioned the feasibility of trying to control it with fungicides such as Bravo or Quadris. I do not have any data to support this for brown spot here, but for other foliar diseases such as Cercospora leaf blight in Arkansas, Quadris significantly reduced disease and increased yields in one test even at half the labeled use rate (6.1 fl oz/A). The important thing to factor in is the timing of applications. The increase in control and yield was accomplished when the fungicide was applied at R3 (Beginning pod, pods ¾ in. long) or at R3 and R5 (beginning seed, seed 3 mm) but not at R5 alone. This was my experience years ago trying to control pod and stem blight and anthracnose with fungicides. The early application was critical. If you have soybeans that are still in the R3 stage of development, you may get a response from foliar fungicides. If applied at R5 or later, it is not likely you will get the desired response. The only way to tell is to leave a strip unsprayed and see what happens. The lowest labeled use rate for Quadris on soybeans is 12.3 fl oz/A.

 

Septoria Brown Spot

 

 

 

Grain Marketing Highlights - Carl German, Extension Crops Marketing Specialist; clgerman@udel.edu

 

Commodity Markets Focus on '03 Harvest

Favorable harvest weather over the next two weeks should allow commodity traders to get a handle on U.S. corn and soybean crop size by the time the October 10th crop report is released. Currently, speculation suggests that the U.S. corn crop will get larger and the soybean crop will get smaller. Bulls and bears are likely to be evenly divided on that question until the production estimates are in.  Corn and soybean futures are currently rallying due to a favorable weekly export sales report.

 

Market Strategy

Short crops are said to have long tails, meaning that prices typically peak just prior to, during or shortly after harvest. Just when prices peak depends upon what happens to the production forecasts from the September estimate to the actual harvest. The recent rally in new crop soybean prices should be rewarded with sales. The U.S. soybean crop, now projected at 2.643 billion bushels is well below previous production forecasts.

 

It may be advantageous to move early harvested corn at premiums currently being offered (+40 over Dec "03 futures), if available.  Otherwise, further corn sales should be placed on hold, due to price level and basis considerations.

 

 

 

New Herbicide Label for Pastures, Hay and Non-Crop Sites - Mark VanGessel, Extension Weed Specialist, mjv@udel.edu

 

BASF has labeled Overdrive for use in pastures, hay, and non-crop uses.  Overdrive is a combination of dicamba and difluenzapyr (same combination as Distinct).  Overdrive controls a wide range of broadleaf weeds, but will not control grasses.  Overdrive can injure newly seeded grasses, so it should be used only on established pastures and hay fields.  There are no grazing or harvesting restrictions.  Overdrive can be tankmixed with other herbicides.