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IPM Message 2004

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MAY 14
Blackheaded fireworm populations in many areas of the growing region have already exceeded action thresholds. If you have not yet started sweeping, you should go out ASAP. Not all bogs have infestations, but we have heard of multiple bogs that have had populations that needed control. Many sprays have gone out this week. Just about all of our registered insecticides have activity against BHF including Confirm, Intrepid, Diazinon, SpinTor, Lorsban, Sevin, Orthene, and Guthion. You may also opt to use the sprayable pheromone. The threshold for BHF is 1-2 larvae per sweep set. Cranberry weevil populations have also been reported to have exceeded action thresholds this past week.
Growers have been spraying Avaunt (available on Section 18 permit). Weevils must come into contact with this chemical to be affected. There is some concern of reduced efficacy if cold weather (less weevil activity) quickly follows an application. It is not known how long Avaunt may actually stick around after an application. There have also been reports of Spag in the western locations of the growing area. Keep a good lookout for these larvae. Both BHF and Spag larvae are very small and wriggle when touched.
Kerb applications (available by Section 18 permit) have also been going out. Two applications can be made and all applications must be made prior to June 15. I made a recommendation not to use Kerb on flow-through bogs. This is my recommendation and not specifically written on the label. There are water quality concerns with Kerb and all efforts should be made to avoid negative impacts on water resources.

MAY 19
The following info was discussed at the first Bogside workshop held on Tuesday May 18.
Floods for BHF worked last week, but do not seem to be working this week. The larvae are too big. In addition, it is getting late to be putting on a flood. Typically, floods onto vines passed cabbagehead can cause injury. Many cmpds are listed to control BHF, but according to Anne and Marty, the short list consists of Diazinon, SpinTor, Confirm, and Intrepid. Avaunt will have activity against BHF, but you must have resistant weevil on your bog to apply Avaunt. Avaunt efficacy decreases as washout times increase. Use on well-timed systems. BHF populations can be patchy; be sure to sweep thoroughly. Lorsban is NOT a good choice for BHF as it is not effective. We do not have good data for Orthene, so you can use this product at your own risk. If your neighbor's bog is abandoned, it could be a healthy source of BHF. Since vine productivity is not an issue, you could ask neighbors to flash flood to control their populations, if warranted.
Annie is recommending using the Pherocon 1C wing trap for BHF since it is a larger trap and populations seem to be much higher than in years past. This is the same trap you have traditionally used for Spag. Traps should be out by June 1 and put 1 trap out for every 10 acres. Monitoring for BHF is done a bit differently now, if you are using Intrepid. You are trying to determine the biofix or the first indication of moth flight. Check the traps every 1-2 days until you catch at least a few moths (more than just 1 or 2). Ovipositioning starts about 1 week after the start of moth flight and peak ovipositioning occurs 2-3 weeks after the biofix. This is when you should apply your spray (2-3 wks after biofix). Do not judge it by peak flight. If you are very concerned about your infestation, you can put out more traps (2 per 10 acres) and check every day to catch the biofix.
Cranberry weevil: Avaunt can only be used for the first generation. The Section 18 permits application pre-bloom only. You must send in paperwork to MDAR by September 30. Guthion is not recommended for cranberry weevil control.
Gypsy moths, blossomworm, cranberry weevil, and green spanworms are all out. The season seems to have started early this year. Everyone should be out sweeping by now! You can use Intrepid, Confirm, SpinTor, Diazinon, Sevin, Orthene and Lorsban for cutworm control. Remember, Intrepid has Zone 2 restrictions. Great CB spanworm may also be netted from time to time. Remember, the threshold for these spanworms is much lower, usually around 5 on average.
Other notables mentioned at the workshop: Tent caterpillars do not eat cranberry, so don't worry about them. Winter moth may eat cranberry, but we haven't heard of any problems yet this year. Remember to ignore sawflies in your sweep net. They do not eat like cutworms and if you count them in, you could artificially inflate your numbers. The next workshop is scheduled for June 2 at 9-10:30 AM at the Cranberry Station.

May 25
Just to clarify any confusion from last week…. The discussion concerning using a biofix was for using Intrepid. If you will be using the other conventional insecticides, track for peak flight and apply 10 days later. The efficacy of Intrepid is improved with well calibrated systems. Green spanworm and humped green fruitworm are getting harder to control as the larger instars become more prevalent.
Applications of Avaunt against early season CB weevil seem to be working well. The cool, windy days have hampered sweeping efforts to detect any resurgence in weevil populations. Be sure to get out there and sweep as soon as the weather warms back up. We still have not heard about the Section 18 permit for the insecticide that would be used against second generation weevil. We will keep you posted.
Many growers have put out their first fertilizer applications. Frost tolerance is at 29.5 for all varieties. The next workshop is scheduled for June 2 9-10:30 AM at the Cranberry Station. Return to top of page.

June 3
This information was discussed at the second bogside workshop held on June 2, 2004 Blackheaded fireworm moths are flying. Make sure your traps are out if you plan to treat either with Intrepid or with other conventional insecticides. Larvae have been pupating in the lab early in the week. Spag is also out flying. Your traps should be out for Spag as well. Blossomworm seems to be having a good year and is getting harder to control as is humped green fruitworm. Chocolate or dark brown has been noted, but has not been common. Be sure to keep sweeping though bloom. True brown spanworm can show up as threadlike larvae clinging to the rim of the net. CB weevil came on early this season, many people treated, but weevil has not seemed to resurge in numbers. However, if temperatures warm, weevil numbers may rebound. Marty has seen second generation weevil from blueberry.
Sprays for upright dieback should have gone out already. Champ and Bravo can be used for URD. Ferbam applications can be made for fairy ring; earlier applications work better than later applications. Frank has seen some early hook on sanded Early Blacks. We could see scattered bloom early next week if temperatures warm up. If you see any funky flower on your bog, please let Frank know. It tends to show up on EB for the most part. Frank reports that the KQF tabulated 7 out of 16 points. This translates into very good to excellent keeping quality. You can decrease the rates and/or the number of fungicide applications this year, if desired. If your bog has a history of bad fruit rot, you should maintain your normal fruit rot prevention program and do not cut back. Please let Frank know how Abound is working for you. Use Abound only once and Frank recommends using it first.
Keep in mind that nitrogen will be released into the soil and be absorbed by roots more as the temperatures continue to rise. If you have put out fertilizer, be patient before applying more. Uptake will be slower when temperatures are low. Wait to see if you get a response before applying increased doses. Return to top of page

June 9
Black-headed fireworm moths are flying. You should have your traps out if you plan to use Intrepid or conventional insecticides. We have heard some good reports about the effectiveness of Intrepid on BHF even in bigger systems with long washout times (~8 minutes). Spag and brown spanworm moths are also flying. Folks are still picking up Spag larvae in their nets, sometimes in high numbers. Anne reports that people have been netting Spag larvae of various sizes. Keep sweeping through bloom so you can catch brown spanworm larvae. Remember the threshold is 18 per sweep set for them.
The entomology lab has also seen striped colaspis adults out. Admire can be used to manage these insects. Check the June newsletter for more information on Admire. Admire cannot be applied during bloom as it is toxic to bees; it is best to wait until afterwards to spray. Recommendations are to spray within 1-2 weeks after seeing peak flight. Adults can be picked up in your sweep net. Remember Avaunt cannot be used once bloom has started. So if you plan to treat for cranberry weevils, you should do so soon.
Annie's general feel is that this may be another strange year for cranberry fruitworm. Be sure to do your out-of-bloom counts. It is likely that you may want to shorten the traditional interval for spraying after 50% out-of-bloom. We still have some time on this issue and will provide more information as the time gets closer.
The next workshop is scheduled for Tuesday June 15 9-10:30 AM at the Cranberry Station library. Return to top of page.

June 16
Some growers report that BHF moth populations have peaked. Growers from the Cape report that their populations are still climbing. If you are in a Zone 2 and want to use Intrepid, you must have documentation of failure of all other alternatives. If you feel that you fall into this category, contact the Ent lab and discuss your situation with Anne or Marty. BHF eggs hatch within in 3-10 days of laying. Act accordingly; don't delay. Use a sticker with Intrepid as per the label.
Spag larvae in all sizes are still being reported. Moth flight has started. Brown spanworm moths are flying like crazy. Larvae should be showing up soon. Keep a lookout for slender brown larvae on the rim of your sweep net. Cranberry fruitworm moths have been flying since last week. Annie is still recommending shortening the interval between 50% out-of-bloom and the timing of your first spray. Moths are just waiting to lay eggs, so be ready as soon as fruits start to form. Confirm and SpinTor are not good choices for CFW. Intrepid could be used but only with low gallonage, efficient systems.
If you have dead spots showing up on your bog, look for beetle grubs. Please call the Ent lab (ext. 20) if you think you have a beetle infestation. Admire can be used for striped colaspis and oriental beetle.
Keep in mind the difference between "in bloom" timings and "% out-of-bloom" timings. In-bloom timings are using for fertilizer applications and fungicide applications. In-bloom refers to anything that is an open flower or beyond; flower pods do not count. % out-of-bloom uses all flower parts (pods, flowers, open blooms and fruit) in its calculation and is used to time cranberry fruitworm sprays. Bloom time fertilizer should be applied at about 75% in-bloom. Then, depending on response, add the second dose 10-21 days later.
Frank has seen some umbrella bloom out there. Usually, this is caused by partial bud damage resulting from frost injury. In this case, he thinks it may be a result of winterkill injury that was not severe enough to kill the entire buds, but did cause damage to the leaf bud tissues. Injury of this sort may take at least a year for the upright to return to its biennial bearing pattern. Depending on the variety, the recovery may be more or less pronounced. Stevens are more dependent on more upright repeating bloom, so yields could be affected. EB and Howes only rely on about 25% of their uprights repeating bloom, so yield impacts may not be as obvious.
Early bloom is just starting to show up; 5% on EB and 8% on Ben Lear on State Bog. Once the weather warms, it should move along quickly. Be ready to apply your fungicides. Since the keeping quality is very good to excellent, you can reduce your number and/or rates of fungicide applications on bogs with low rot history. If doing 3 applications, start at about 15% in-bloom; if doing 2 applications, start at about 50% in-bloom, and if doing 1 application, apply at about 85% in-bloom. Frank recommends NOT tank mixing Bravo with any other pesticide. Try your best to keep the spray intervals between 10 to 14 days.
If you have had high rot in your Stevens vines that cannot be easily explained, please contact Frank (ext 18). He would like to do some sampling to see if he can figure out why Stevens have been prone to high fruit rot over the last few years.
The fourth workshop is scheduled for Wednesday June 30 9-10:30 AM at the Cranberry Station library. The IPM message will be updated by Wednesday June 23. Return to top of page.

June 23
Many growers have been applying first fungicide sprays this past week. Ferbam is not being manufactured anymore and most local ag suppliers do not have any in stock. However, it is still legal to apply the fungicide if you have some left over. If you are going to use Abound, it should be used as your first spray.
You may not apply Avaunt at this point (bloom should be out in some degree at all bogs). The expiration date on Kerb applications has also passed. We have not heard any definitive news on an insecticide for the summer generation of CB weevil. We will keep you posted and let you know as soon as we hear anything.
Black-headed fireworm moths seem to be on the increase even though we thought we hit the peak last week. We recovered more than 200 moths from our trap this Monday. Some growers have asked about mixing Intrepid with their Bravo applications. The conventional wisdom is to not tank mix Bravo with any other material. However, several growers are trying a combination of injections (injecting Bravo first and then Intrepid towards the end of the injection period). The two are not physically mixed. We will let you know if any problems develop.
Brown spanworm larvae have been showing up. Look for them as thread-like light brown worms on the rim of your net. They may be in the leaf litter as well, but are much easier to see on the rim. SpinTor or Confirm can be good choices for brown spanworm. Remember, brown spanworm infestations can be quite patchy. Look for signs of damage to the uprights. The ent lab is still picking up Spag larvae. They have been fairly large in size. It is unusual to be picking up larvae this late in the season, but this is what has been seen.
Return to top of page.

July 1
This information was discussed at the third workshop held on June 30, 2004. We have hit 40% out-of-bloom (oob) with the Ben Lears on State Bog as of this morning. CB fruitworm moths (CFW) are out and flying. Annie recommended using Diazinon for the first CFW spray. It is a very important spray. Some folks are considering combinations of Diazinon with Intreprid or Confirm but this is not really a good option. The Diazinon slows the insects down so much that they don't eat enough Intrepid to do a good job. We do not have a lot of data for Intrepid with CFW, but it works better in low volume situations.
Sampling for CFW. Take random samples. Moths prefer berries that stick out, fruit that are on the margins or inner ditches, so be sure to pick fruit throughout the canopy and all over the bog. Females do not tend to lay eggs in pinheads.
When people say they are "washing off" an insecticide, what they are really doing is delaying bee activity. You are not washing off the material once it has dried on the foliage. In fact, we are not sure if you lose some efficacy of the material by irrigating the next day. However, if you need to protect your bees, please run the sprinklers.
Annie expects the numbers of CB weevil to increase during the first 2 weeks of July. We still have not heard about our emergency material for second generation weevil. Intrepid has been doing a good job on BHF. Oriental beetle seems to causing some significant problems in areas. Striped colaspis is primarily found in upland bogs, not in peat bogs. You can pick them up in your sweep net, especially in dead areas. You may see notched leaves, just like black vine weevil.
On the disease end, things are pretty quiet. KQF is still holding. The weather has been favorable for pollinations (dry and warm). If you see funky flowers or false blossom in your bog, please let Frank know (ext. 18). You can mix Dithane with other chemicals if you would like. It is not as problematic as Bravo.
The last Bogside workshop will be held on Tuesday July 13 9-10:30 AM at the Station Library.
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July 12
Actara is now available under CRISIS EXEMPTION. Please link to fact sheet for more information.

July 14
This information was discussed at the last workshop, held on July 13, 2004.
A Crisis Exemption has been issued for the use of Actara for cranberry weevil control. You need to prove you have a crisis situation (bring sweep count numbers). You must get paperwork from the Entomology Lab before you can purchase and use the material. It is a restricted use compound and has a high leaching potential. It is important to continue to sweep for weevils. On State Bog, the Ent lab is seeing a lot of weevils still in the egg stage, which is unusual. High numbers (>100) have been reported. Actara has a 12 hr REI and and 30-day PHI. Historically, CBW have moved off-bog by August, but in the past few years, they seem to be hanging around.
BHF larvae are out there. This means moths will be flying and laying eggs again. Annie puts out the same recommendations as for controlling the spring generation. The eggs are the overwintering stage. There seem to be big geographic difference as far as development and peak flight for black-headed fireworm.
Keep scouting for cranberry fruitworm eggs. The pressure is out there. We discussed drying times for chemicals. Typically, chemical companies recommend 3-6 hours, but Steve Ward mentioned that he has seen good results with 2 hr dry time, especially with contact poisons like Lorsban. Lorsban does work for CFW (but not for BHF), and Diazinon and Sevin are good choices for CFW. For folks using chemicals with a strong odor, several growers have tried added scents to the mix and they have worked pretty well. The materials are cheap and available at local Ag dealers. These really help to minimize neighbor complaints.
Carolyn has had several reports of Yellow Vine Syndrome. Stevens seem particularly susceptible, and then next is Ben Lear. YVS is associated with fluctuating water table issues; either it is too wet or too dry. Casoron use seems to exacerbate the syndrome, but is not the cause of it.
You should consider using a light dose of fertilizer in early August for bud set, especially if the fruit load is high. If your uprights are short above the fruit, you can add some NPK (a decent dose) after fruit are set. Urea will be absorbed readily through the leaves. It is activated by moisture (dew is usually sufficient), but will respond to light rain or irrigation as well. Urea can be applied at 2-4 lb/A. If your system is not very good, do not use too much or you will get uneven growth patterns. Urea will not help fruit set, but will help bud set.

July 23
Acres are still available for Actara applications for control of cranberry weevil. If you haven't done so already and you have excessive populations of weevil, see Marty to get the paperwork to obtain Actara. Call her ahead of time if possible (ext. 20). Bring your sweep records with you for documentation of a crisis situation. CBW should be moving off the bog soon.
Spag and black-headed fireworm larvae have still been reported. Nothing out of the ordinary; they have just been picked up in sweep nets. Flea beetle is starting to come out. You should continue to sweep for flea beetle, especially if you have had infestations in the past. Sevin or Diazinon can be used for flea beetle. CB fruitworm pressure is still out there. You should be monitoring fruit for viable eggs. Intrepid can be used for long-term control on good systems (if you are not in Zone 2).
Just a reminder. There is a 14-day interval between Diazinon applications that must be observed.
There are some healthy populations of dodder out there. If you feel you had a failure with Kerb, please let me know: . I think folks went out a bit early and may have missed the peak emergence; it was later this year than usual. You can try using a 20% solution of Simple Green for postemergence control. Apply as soon as possible and do multiple applications if you have the time. See the July newsletter for more information on using Simple Green. Otherwise, the fruit seem to be sizing well. Make sure the vines are well watered, especially if we keep in this rain-free period.

August 9
Evidence of heavy cranberry fruitworm damage have been reported in some areas. The Ent lab thinks that early heavy pressure has contributed to the damage levels, especially if there were long intervals between spray applications. Cranbery weevils populations have moved off bog and numbers are very low. Infestations of flea beetle have also been reported. Sevin and Diazinon are good choices for flea beetle. It is generally thought that populations in the range of 20-30 indicate a spray is needed. If you are not sweeping, you should at least go out and look for evidence of damage, especially if you have had problems in the past.
If you have grubs and are considering using Admire, your window of opportunity is quickly closing and you should apply soon.
BHF and Spag populations are still out there. If you have been chasing these pests early in the season, you should continue your monitoring because more damage could be done.
The CCCGA Annual Meeting will be held at the Cranberry Station on Tuesday August 17, starting at 9 AM.
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August 20
Insect activity is slowing down now as the fruit are starting to color. Many growers will be discontinuing inspection of fruit for cranberry fruitworm this week, if they have not already done so. CB weevil is off the bog. Flea beetle may still be out as well as Spag. Many insecticide sprays have gone out this year to combat the many insects, but at this point in the season, additional sprays are not typically recommended.
Frank also concurs, that even with the large amounts of rain that we received early this week, there is no recommendation for additional fungicide sprays. The weather has been very cooperative and our rain events have been followed by at least a day or 2 of sunshine. There is relly no need to apply an additional fungicide for fruit rot protection as this point even if we get more (and frequent) rain events.
We have heard some rumors that folks are thinking that cranberry fruitworm has become or is becoming resistant to Diazinon. We do NOT believe this to be the case. There are significant infestations of fruit out there, but it is most likely due to the very high CFW pressure that was present early in the season. We do not have any evidence to support insecticide resistance by CFW.
This will be the final message for the 2004 season. Thank you for coming to the web page for the IPM Message.


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