Virginia AG Pest Advisory
| Aug-21-2008 Fruits and Vegetables (General) (Insect) From Helene Doughty |
Insect Activity on the Eastern Shore for the week ending 8/21/08 The Pheromone Trap catches were as follows for this week (7 nights): Corn earworm traps: ESAREC: 582 Bobtown: 11 Melfa: 1 Nassawadox: 56 Eastville: 208 Beet armyworm traps: ESAREC: 31 Melfa: 0 Eastville: 239 Fall armyworm traps: ESAREC: 10 Keller: 0 Eastville: 25 The blacklight trap catches were as follows (for a total of 7 nights): ESAREC: 51 corn earworms, 8 european corn borers, 5 beet armyworms, 64 green stink bugs. Cheriton: 115 corn earworms, 15 beet armyworms, 6 fall armyworms, 8 green stink bugs. Capeville: 21 corn earworms, 10 beet armyworms, 9 green stink bugs. Horntown: 112 corn earmworms, 23 beet armyworms, 4 fall armyworms, 16 green stink bugs. |
| Aug-21-2008 General Comments (Insect) From Sean Malone |
Brigade 2EC insecticide/miticide now labeled for soybean and peanuts FMC Corporation's product Brigade 2EC, which is a 25.1% formulation of bifenthrin, the same active ingredient in the product Capture (FMC Corporation), now has a label for foliar treatment of spider mites in both peanut and soybean (5.12 to 6.4 fluid oz/A for both crops). Foliar treatment of corn earworm is also on the label (2.1 to 6.4 fluid oz/A for both peanut and soybean). Please read the label for additional remarks and regulations: http://www.fmccrop.com/Portals/crop/Content/Docs/Labels/Brigade%202EC%206-6-08%20R%20Field.pdf |
| Aug-20-2008 General Comments (Insect) From Ames Herbert |
Update on corn earworm/cotton bollworm Corn earworm moth activity is gradually increasing or holding rather constant in most areas. As we predicted, because of the differences in the maturity and degree of drought stress in the corn crop, moths are coming out over a long period of time. We like to see a single strong peak that we can deal with and be done, but that is not happening this year. Because moths are emerging over a long period, we see hits here and there, some light some heavy, depending on a lot of factors. We are getting reports of soybean fields being treated from the southern most fields in Suffolk and Southampton, through the Middle Peninsula, to the Northern Neck. Some of these fields are at or above threshold. We are also hearing of fields with only a very few worms, well below threshold. This variability makes it difficult to decide which fields need to be treated, and means that only a good reconnaissance effort can determine the actual need. This scattered, long lived moth flight also means that fields that are infested now may get a second attack in 2 to 3 weeks. This is important: remember, if any field is treated this week or was recently treated, that field will be at very high risk to a second infestation. Beneficials in those fields have been reduced so any new eggs deposited by moths and the emerging young worms will have a better chance of survival. We have written about the importance of adjusting the economic threshold for the high bean prices. Use the Corn Earworm Calculator to adjust the threshold for your situation, remembering to input your estimated spray cost and estimated per bushel bean value. Access this handy tool at http://www.ipm.vt.edu/cew. Good news for cotton growersaccording to our samples this week, Bollgard II and Widestrike varieties are holding strong against bollworm attack. In a series of test plots, percent damage by worms is at about 1-3% in untreated Bollgard II or Widestrike cotton and almost 0% if treated one time with a pyrethroid. Bollgard varieties are experiencing a bit more damage, but with pyrethroid treatment, they are holding well too. |
| Aug-20-2008 Peanut (Insect) From Ames Herbert |
Spider Mites in Peanut and Reports of Corn Eaworms and Fall Armyworms Twospotted spider mites are beginning to show up in peanut fields in the drier areas. Mites are always a tough pest to deal with because they attack drought stressed peanuts that are already lagging in yield potential. We have only two legal mite control options in peanut: Danitol and Comite. Danitol can be used at 10 to 16 oz/acre. It offers the advantage of also protecting against corn earworm and potato leafhopper. However, since Danitol is a pyrethroid, it will do a good job of killing adults and immatures, but will not kill eggs, which could result in a rebound if a lot of eggs are present at the time of the application. Comite at 2 pt/acre (or Comite II at 2 ΒΌ pt/acre) is the other option. Comite does a better job killing mite eggs, but does not protect against the other insect pestsworms or leaf hoppers. Both products work best if applied early in the infestation cycle before mite populations are exploded. Applying early in the cycle can often prevent population explosions. If you can see the mite damage from the edge of the field, mites populations are high, at least in those areas. Unless weather changes and we begin getting some more regular rains, it may take two applications at short spray intervals to bring exploded populations under control. In order to break the cycle, the second application has to be applied within 5 to 7 days of the first. Of course these represents a lot of cost and would only be profitable if there is good yield potential. Several peanut fields are reported to have become infested with worms. Thresholds are very high for peanut, 4 to 6 worms per row foot, because worms only eat the leaves and by this time in the year, plants can stand a lot of leaf feeding without any impact on yield. I did get some reports of what sounds like fall armyworms mixed in with corn earworms. In peanut, fall armyworms are leaf feeders too, so are not a great concern. They are more difficult to kill with pyrethroids. |
| Aug-19-2008 General Comments (Other) From Tom Kuhar |
3rd Annual Fall Vegetable Field Day at Eastern Shore AREC Dear Friends and colleagues, You are cordially invited to join us for our 3rd Annual Fall Vegetable Field Day at Virginia Tech Eastern Shore AREC near Painter, VA. The Field Day will be held on Tuesday, September 16, 2008 and will begin around 4:00 pm and will conclude with a meal. The details for the field day and the program are not complete at this time, but there wil be plenty of pest management and variety trial work to present on a number of vegetable crops including tomatoes, green beans, seedless watermelons, lima beans, peppers, cucurbits, sweet corn, and cole crops. We hope to see you there. |
| Aug-14-2008 General Comments (Insect) From Sean Malone |
Corn earworm moth catches for the week ending Aug. 14, 2008 Blacklight trap and pheromone trap corn earworm moth catches were similar to last week across eastern Virginia. Please see the attached table for further details. [More] |
| Aug-14-2008 Fruits and Vegetables (General) (Insect) From Helene Doughty |
Insect Activity on the Eastern Shore for the week ending 8/14/08 The Pheromone Trap catches were as follows for this week (6 nights): Corn earworm traps: ESAREC: 149 Bobtown: 1 Melfa: 0 Nassawadox: 96 Eastville: 32 Beet armyworm traps: ESAREC: 22 Melfa: 0 Eastville: 517 Fall armyworm traps: ESAREC: 22 Keller: 1 The blacklight trap catches were as follows (for a total of 7 nights): ESAREC: 18 corn earworm, 21 european corn borer, 3 tomato hornworm, 34 green stink bug. Cheriton: 249 corn earworm, 29 beet armyworm, 3 fall armyworm, 22 green stink bug. Capeville: 34 corn earworm, 39 beet armyworm, 4 green stink bug. Horntown: 92 corn earmworm, 32 beet armyworm, 7 fall armyworm, 18 green stink bug. |
| Aug-13-2008 General Comments (Insect) From Ames Herbert |
Corn earworm update Corn earworm is slowly gaining ground but to date, mostly in peanut fields. Although we are finding peanut fields with worms, there is very little evidence of leaf feeding. Typically earworms do not do enough feeding in peanuts to warrant control, although most growers still apply insecticides, mostly tank mixed with a fungicide spray. We have not seen or gotten word of any threshold level infestations in soybean but I expect that my change beginning next week. We will be continuing our pyrethroid resistance monitoring program through the middle of September and will post updates. |
| Aug-13-2008 Soybean (Insect) From Ames Herbert |
Soybean aphid update, first siting Soybean aphids have be spotted in a few soybean fields in Northern Neck counties, but only one or two per 20-plant sample, well below the 250 per plant threshold. There is a possible siting in Shenandoah County, we are waiting for the sample to confirm the species. We will continue monitoring for soybean aphids at least through the middle of September and post any news. |