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Monday, May 30, 2011

Blueberry maggot flight begins in southeastern North Carolina

Oneal blueberries ripening at The Bush & Vine, York, SC.  Photo: HJB
We captured our first blueberry maggot (Rhagoletis mendax) adult, a female, at the Ideal Track of the Horticultural Crops Research Station, Castle Hayne, NC.  This marks the beginning of the blueberry maggot flight, right on schedule for the historic average flight time, 25 May.

We are monitoring blueberry maggot flies and other insects at 15 locations in southeastern NC.  We not caught flies at any of the commercial blueberry farms, nearly all of which are following the calendar-based management program for blueberry maggot and began treating at least 2 weeks ago.

View blueberry maggot, sharpnosed leafhopper, and SWD captures from NC blueberry country here.  Ideal Track is Site 14 in the blueberry maggot trapping list.

More information

Blueberry maggot and sharpnosed leafhopper monitoring data now available UPDATE: SWD data now added

Sunday, May 29, 2011

Wake County cooperative extension cut

Cooperative extension has been disproportionately cut throughout the country at both the university and county levels but this week the cuts came close to home.  The Wake County Commission has eliminated funding for the horticultural extension agent for the county.  Although Wake County is home to Raleigh (the 2nd largest city in NC), Cary, Gardner, and other urban areas, it is also the 4th largest nursery & floriculture producing county, the 12th largest sweet potato producing county, and the 17th largest tobacco producing county.  This production occurs on 827 farms that cover 84,956 acres.  (Source: NCDA & CS)

The economic value of agriculture to the county isn't the whole story, however.  City dwellers in Wake County benefits from the growing local food movement, spearheaded by cooperative extension's 10% Campaign, and the NC Master Gardener program.

Cutting extension is a short sighted solution to a budget problem.  The modest investment in extension personnel and programs ($22,000 per year, in the case of the Wake County horticulture agent position) has real and tangible benefits.  Adding salt to the wound is the fact that the rest of the Wake County employees will receive a 2% raise this fiscal year.  With cuts like this, extension will come out of the recession a much weakened institution but still tasked with helping America's farms feed, clothe, and support the world.

More information
Wake County Board of Commissioners

Tuesday, May 24, 2011

Insect activity beginning in the research hop yard

Caterpillars feeding on a hops leaf at the Lake Wheeler Field Laboratory. Photo: HJB

Yesterday, undergraduate intern Mandi Harding and I visited the research hop yard at the NC State Lake Wheeler Field Laboratory to check the traps we placed last week, collect mite & aphid samples, and observe any insect activity. The plants are just starting to reach to the top of the trellis, so I didn't necessarily expect large insect populations. I was correct in that there was minimal activity, but we did see some notable insects eating hops or eating other insects that were eating hops. Several plants had recently hatched caterpillars (see above) present, and they all appeared to be the same species. Rather than collecting these larvae and rearing them in lab, we are going to keep an eye on them in the field and collect them when they are closer to pupation.

There were also plenty of beneficial arthropods (insects and mites) present, including lady beetles, predatory mites, minute pirate bugs, and lightning bugs (which are actually beetles and are one of my favorite things about living east of the Mississippi). Thrips were clearly visible crawling on leaves and inside cones. Thrips are potential pests of hops in the southeast, and I am always amazed at the sheer number of thrips present in the early summer in North Carolina. I am even more impressed when I talk to cooperators on research projects in the Pacific Northwest who catch on the order of 10-15 thrips per trap, and we catch 0ver 300 in the same time period. Thrips seem to thrive here, for better or worse. Also thriving are thrips predators, like the lightning bug (beetle) below.

A lighting bug feeding on thrips on a hop leaf. Click here to enlarge this image for a better view of the distinctively striped soybean thrips highlighted. Photo: HJB

We'll be collecting samples and observing insect populations in the hops yard throughout the summer and will post updates when interesting insects appear.

Monday, May 23, 2011

What to watch for: Raspberry cane borer

Damaged blackberry primocane at the Sandhills Research Station, May 23, 2011.  Photo: HJB
While checking our virus vector monitoring plots today at the Sandhills Research Station, near Jackson Springs, NC, I noticed a few plants with classic raspberry cane borer injury.  Female raspberry cane borer beetles lay their eggs near the tip of primocanes causing the end to wilt and creating a distinctive, paired girdling of the cane.

Raspberry cane borers are one the many exciting "boring" insects that feed on caneberries in the southeast.  If left unchecked, the larvae can kill the cane they feed on over the course of 1-2 years, depending on where in the US they are.  In North Carolina, these insects probably have a 1 year larval life cycle.

The injury at Sandhills was very recent, as evidenced by the fact that the end of the cane was just wilted and not dead.  In addition, no larvae were readily found in the cane when I tore it open, suggesting that the eggs have not yet hatched.

Cultural control, via removal of infested canes, is the recommended management strategy for both raspberry and rednecked caneborers, and this is the perfect time to remove raspberry cane borer infested tissue!  Infested primocanes can be tipped, and will continue to grow over the course of the summer.  If left until fall, during the typical pruning period, the entire damaged cane must be removed to ensure the raspberry cane borer larva is destroyed.  Neither raspberry or rednecked cane borer injury typically damages more canes that would be removed through typical fall/winter pruning in North Carolina.  We generally only see significant raspberry or rednecked crown borer injury at locations where pruning has been minimal.  Now is a good time to scout for borers are remove the damaged plant parts before they can get a foothold.

More information
Blackberry borers can mean big problems

Tobacco budworm update

Calls about tobacco budworm have begun in earnest this week, and the main questions I am hearing are "What is the difference between BeltTM(Bayer CropScience) and Coragen® (DuPont)?" and "I used BeltTM/Coragen®, how long should I wait before I decide if I need to treat again?"

First instar tobacco budworm larva in eastern North Carolina tobacco. Photo via Loren Fisher.

What is the difference between BeltTM and Coragen®?
BeltTM and Coragen® are two recently registered insecticides for use in tobacco against Lepidopteran (caterpillar) pests. Both these insecticides share a common, and novel, mode of action. They act on ryanodine receptors, which form calcium channels in muscle cells, and inhibit muscle contraction. The Insecticide Resistance Action Committee (IRAC) places both of these materials in Group 28 (ryanodine receptor modulators). In other words, BeltTM and Coragen® kill insects in the same way and using one following the other does not represent a rotation.

In our research trials over the last 3 years, BeltTM and Coragen® perform similarly to one another when applied as foliar treatments. They also perform similarly to the standard insecticide used for tobacco budworm control, Tracer (spinosad, Dow AgroSciences). The key difference between BeltTM and Coragen® is the potential in-plant movement of the latter. Coragen® is xylem mobile, which means that it moves in the plants water channels when applied to the soil. Coragen® has a transplant water label in tobacco, but our data on the efficacy of this application method is limited.

I used BeltTM/Coragen®, how long should I wait before I decide if I need to treat again?
Both BeltTM and Coragen® slow or stop feeding quickly. However, larvae may appear alive, but sickly (or moribund) for up to 4 days after treatment. Another insecticide application should not be made until sufficient time has passed to allow for the insecticide to work. If another treatment is considered necessary, growers should be sure to rotate to another mode of action.

As always, when I discuss treatment thresholds (10% infestation) for tobacco budworm, it is important to understand that these thresholds are very conservative, meaning that yield loss has rarely been documented due to budworm feeding, even at much higher infestation rates than 10%.

More information

Strawberry season coming to a close

After another short picking season, we are pulling the plug on our strawberry research plots at the Central Crops Research Station near Clayton, NC this week. The spring of 2010 was also a quick, short growing season, and I am curious how many other strawberry farms are wrapping up harvest in the next few weeks. I am also curious if this pattern is related to our cold winters, and if short seasons are the norm under these conditions. We will maintain our planting for the next few week to monitor for spotted wing drosophila, but our two mite trials have ended because the plants are growing more foliage than fruit at this point.

SWD trap in strawberry plots at the Central Crops Research Station, 2011. Photo: HJB

It's always a little bittersweet to end a field project, so I read the latest post from Berry Girl, a relatively new strawberry grower near Goldsboro, NC with interest. They, too, are ending their field season for the year and looking towards next year. I've enjoyed reading their blog this spring and hope they keep it up!

More information
Bowing out - The True Adventures of Berry Girl

Sunday, May 22, 2011

Blackberry field visits, May 26th

Green June beetle feeding on ripe blackberries at the Lower Coastal Plain Research Station, Kinston, NC in 2009. Photo: HJB

I will be in southwestern North Carolina this Wednesday and Thursday for a Southern Region Small Fruit Consortium sponsored agent training. Following the training on the 26th, I will be visiting several blackberry growers to discuss SWD monitoring and management. SWD have been detected in several counties in southwestern NC and northwestern SC, and large populations were present in a non commerical planting in 2010. Blackberry & raspberry growers should be aware of their management tools and be prepared to both monitor and treat in 2011.

More information
Insecticides registered for use in caneberries & their potential use against SWD

Thursday, May 19, 2011

Blueberry maggot and sharpnosed leafhopper monitoring data now available UPDATE: SWD data now added

Last summer, we conducted extensive blueberry maggot monitoring at 14 North Carolina locations with the goal of determining the size of our populations, improving management tools, and ideally, minimizing pesticide applications. We found that blueberry maggot populations in southeastern North Carolina are very low. We caught a grand total of 3 flies after checking our traps over 1600 times! This year, we have expanded our program to include 15 locations and included traps to monitoring spotted wing drosophila (at 10 locations) and sharpnosed leafhoppers (at 15 locations).

All of our traps are checked weekly (as we recommend), and our data are uploaded the following day. Blueberry maggot and sharpnosed leafhopper captures to date are available below and will be updated as new data are added. Scroll over data points for site and trap capture information.

These trap capture data are collected in Bladen, Pender, and New Hanover Counties in North Carolina and are intended to support the insect management programs of blueberry growers in these areas. As always, management decisions should be made based on site-specific information!

Spotted wing drosophila captures have now been added and will also be updated weekly. New Hanover 1 is located at the Ideal Tract of the Horticultural Crops Research Station, Castle Hayne, NC.

The graphs were too busy when fly sex was included, but it is worth noting that the first flies captured at New Hanover 1 and Bladen 5 were both female. The first male SWD in southeastern NC was captured at New Hanover 1 on Friday, May 20th. This is particularly important for growers, because female flies are more difficult for non expert observers to identify. If female flies consistently appear before males in the spring (as has been observed on the west coast), growers must carefully check trap captures to ensure that they do not miss the beginning of SWD activity and treat in a timely fashion.

Tuesday, May 17, 2011

SWD detected in southeastern North Carolina

SWD trap at Horticultural Crops Research Station Ideal Track, near Castle Hayne, NC during 2010. Photo: HJB

In addition to an update on our blueberry maggot monitoring program and a review of SWD monitoring, attendees at of the Blueberry Field Day this past Sunday also got a preview of major SWD monitoring news. On Sunday, I captured the first SWD of 2011 in southeastern North Carolina. A female SWD was captured in an apple cider vinegar baited trap at the Ideal Track of the Horticultural Crops Research Station near Castle Hayne, NC. There are 2 important notes about this trap capture:
1. This fly was caught at a research station, not on commercial grower land.
2. A single female fly was captured, and no larvae have been found in NC fruit in 2011.

SWD detection near NC blueberry growing areas does mean that growers must be vigilant. For growers who treat for blueberry maggot, many, but not all, of the same insecticides are effective against SWD. See here for a list insecticides labeled in blueberries and their possible efficacy against SWD. Growers who are not managing blueberry maggot should carefully consider their management options if SWD has been found on or near their farm.

We are currently monitoring SWD at 31 locations in North and South Carolina. In addition, cooperators are monitoring sites in Georgia, Arkansas, and Virginia. In southeastern North Carolina, there are currently 10 locations on or near blueberry farms. To date, we have captured only one other SWD in 2011, in March in Henderson County at another NCSU research station. These monitoring data will be posted on this blog this week.

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What to watch for: Tobacco budworm

First instar tobacco budworm larva in eastern North Carolina tobacco. Photo via Loren Fisher.

Tobacco budworm populations developing
Tobacco budworm (Heliothis virescens) larvae are beginning to show up in North Carolina tobacco fields. At our research plots at the Upper Coastal Plain Research Station, Rocky Mount last week, we found several infested plants, and yesterday at the Lower Coastal Plain Research Station, Kinston, plots were between 0-10% infestation in most of our trials. The vast majority of the larvae present were recently hatched 1st instars, although a few 2nd instars were also present. This means that egg laying occurred fairly recently and that growers will likely begin to see tobacco budworm larvae in their fields soon. In fact, a consultant called Loren Fisher and I last week to report that he and his staff were seeing budworm larvae in fields in eastern NC. Populations in these fields were near treatment thresholds (10%). As always when I discuss treatment thresholds for tobacco budworm, it is important to understand that these thresholds are very conservative, meaning that yield loss has rarely been documented due to budworm feeding, even at much higher infestation rates than 10%.

Campoletis sonorensis wasp searching for young tobacco budworm larvae, Kinston, NC. Photo: HJB

Natural enemies present
Also present in large numbers at the Lower Coastal Plain Research Station yesterday were large number of red-tailed wasps (Campoletis sonorensis) in search of young tobacco budworm larvae to parasitize. The wasps were so common that it was almost easier to follow them from plant to plant than to search for the newly hatched larvae in buds. The large numbers of parasitic wasps also suggests that many of the larvae we saw this week may not make it to adulthood.

For those growers whose fields have tobacco budworm populations at greater than 10% infestation in small plants, have not observed parasitic wasps, and plan to treat, there are several insecticides available (see the NC Agricultural Chemicals Manual for specific recommendations). Some NC growers have used Coragen (a newer insecticide from DuPont) as a transplant water treatment for preventative control of tobacco budworm. Because there is relatively limited data against tobacco budworm using this application method of Coragen, I cannot say how effective or long lasting its activity may be. It also important to note the size of tobacco budworm larvae feeding on transplant water Coragen treatments. First instar larvae may not have fed on enough tissue to kill them, so growers should hold off on making foliar treatments until 2nd instar larvae are present. Caterpillars eat the vast majority of the leaf tissue they will consume as large larvae, so the injury caused by a 1st instar as it develops to a 2nd will not be significant. However, if growers who used Coragen in the transplant water for tobacco budworm control have 2nd instar larval populations above a 10% infestation level and need to apply a foliar, rescue treatment, they should select a different mode of action material, such as Tracer/Blackhawk (spinosad), Denim (emamectin benzoate), Orthene (acephate), or methomyl (Lannate). Growers who have used Coragen in the transplant water should not apply Belt or Coragen as their first foliar treatment following transplant.

Monday, May 9, 2011

Cicada emergence updates

Thank you to all who have reported North Carolina cicada emergence so far!  You can see reports from other states and add yours at

Steve Bambara, Entomology Extension Specialist, was in Chatham County this afternoon and shared some photos of cicada exuvia.

Cicada exuvia littering the ground and in trees in Chatham County, NC.  Photos: Steve Bambara.
You can also continue to add sighting here.

Sunday, May 8, 2011

Report your NC cicada sightings!

Stealing a great idea from Clemson Cooperative Extension, I'd like to start recording cicada sightings in North Carolina. Report your sightings in the comments for this post. Be sure to mention your city, county, and the date you started seeing cicadas emerge. Remember, a single cicada does not a Brood XIX emergence make--we're looking for the massive, periodic fellas here! Feel free to chime in if you are NOT seeing cicadas, too. That's new as well!

I look forward to reading your comments!

More information
What to what for - The cicadas are coming!

Blueberry Field Tour - May 15th

The 2011 Blueberry Field Tour will take place as the Ideal Track at the Horticultural Crops Research Station, Castle Hayne, NC on May 15th beginning at 3pm. Faculty from the Entomology, Plant Pathology, and Horticulture Departments at NCSU as well as NCDA & CS personnel will be in attendance to share information on ongoing research and extension projects.

I will be discussing our IPM program at the research station, blueberry maggot, and spotted wing drosophila monitoring and management. This last topic has become extremely important in the last week, and it's crucial that blueberry growers be prepared to detect and manage this new pest. Damage has already occurred in other southeastern states, and we have the ability to prevent similar injury in North Carolina. Hope to see many of you next Sunday!

More information
Blueberry Field Tour invitation

Do it yourself - Blueberry maggot monitoring

I have received several questions from growers and homeowners about blueberry maggot monitoring and management over the last few weeks. As part of an ongoing research project, my lab continues to monitor blueberry maggot populations in North Carolina blueberry fields. Our methods were based on those accepted by the Canadian Food Inspection Agency, and can readily be used by growers or homeowners. This post details how interested growers and homeowners can monitor blueberry maggot populations in their blueberry planting.  You can learn about blueberry maggot biology here.

Note that all supplier links are provided for informational purposes. This information is not intended to endorse any particular supplier over another.

What will I need?
Yellow sticky traps (Trece AM-No Bait traps preferred)
Bulk ammonium bicarbonate and vials or "bait enhancers"

From left, bait enhancer vial, AM-No Bait Trap, and bulk ammonium bicarbonate.  Photo: HJB
How many traps do I need?
Trap number depends on the size of your planting. You should always use a minimum of 3 traps for plantings of 5 acres of less. For plantings larger than 5 acres, use the table below (adapted from the Phytosanitary Requirements for the Importation From the Continental United States and for Domestic Movement of Commodities Regulated for Blueberry Maggot, Canadian Food Inspection Agency):

Area of Blueberry Planting (Acres)
Number of Traps
5 or less
Over 100
9 + 1 trap for every additional 15 acres over 100

How do I place the traps?
Blueberry maggot traps should be hung in the upper third of blueberry bushes so that they are clearly visible.  Traps should be hung with the folded end pointed down and the opening upward.  Ammonium baits should be attached to the trap via a twist tie.  Previous research in North Carolina has demonstrated that blueberry maggot adults are more often trapped in large plants and shaded areas.  Therefore, large blueberry bushes with fruit present are preferred for trapping.  Some traps should also be placed near the edges of fields/plantings in weedy areas.
Blueberry maggot trap in blueberry planting in Rockingham County, NC. Photo: HJB
How do I check traps?
Traps should be checked a minimum of once per week, ideally twice per week.  At each trap check, you should also check the ammonium lure.  If you no longer smell ammonia, replace the ammonium bicarbonate.  We typically need to replace the ammonium bicarbonate weekly, so plan for this when you order supplies.  Check for blueberry maggot flies on traps.  Blueberry maggot flies are about half the size of a house fly and have a distinctive "w" pattern on their wings.  Cornell Cooperative Extension has developed a nice fact sheet with photos of other commonly caught flies that may be confused with blueberry maggot.

Remove traps with blueberry maggot flies from your planting and replace with new traps.  If you are new to monitoring, save your traps and have you identification confirmed by your county cooperative extension agent or extension specialist.

We found that we could leave traps in the field for 3 to 4 weeks before they become soiled or full of insects.  Change traps at least every 4 weeks, sooner if they are no longer sticky or the color is obscured by insects, debris, or dirt.
Blueberry maggot adults captured in an AM-No Bait trap.  Photo: HJB
What do I do if I find blueberry maggot flies?
Your management strategy for blueberry maggot will likely differ depending upon the fate of your fruit.  For commercial growers exporting to Canada, you must treat within 7 days of blueberry maggot fly capture.  At least 2 treatments, 7 to 10 days apart must be applied until flies are no longer captured.  Consult the NC Agricultural Chemicals Manual for information on registered insecticides for blueberry maggot.  Be sure to check with your marketer before using any insecticide to ensure that it is acceptable.  This process is repeated if new flies are caught.

For commerical growers not exporting to Canada, the above strategy is also likely the most appropriate, but you may choose different insecticides.

For organic commercial growers, the choices are limited to spinosad (GF-120 & Entrust) and kaolin clay (Surround).  Because there are restrictions on the number of applications of Entrust, one of the more effective insecticides, monitoring is even more important to ensure that unnecessary applications are not made.

For homeowners, check with your local cooperative extension agent for insecticide options and consider using Surround.  Surround coats the fruit with a layer of clay that interferes with fruit detection and egg laying.  This coating readily washes off, but is often not suitable for commercial growers who do not wash their fruit prior to packing it.  Because Surround acts as a barrier, it will need to be reapplied after rain.

What else do I need to monitor?
Growers monitoring for blueberry maggot should also strongly consider monitoring spotted wing drosophila (SWD) at the same time.  Look for a SWD monitoring post to follow soon.

More information
Monitoring supplies
Great Lakes IPM - Traps & Lures

Gemplers - Traps

Blueberry maggot monitoring
Phytosanitary Requirements for the Importation From the Continental United States and for Domestic Movement of Commodities Regulated for Blueberry Maggot
- Canadian Food Inspection Agency

Monitoring and management strategies for blueberry maggot - Michigan State University IPM Resources, Fruit Management Team Alert

Do you have a blueberry maggot problem?
- Cornell University Cooperative Extension

Friday, May 6, 2011

Global Change Forum - June 30th

The NC State University Small Fruit, Specialty Crop, and Tobacco Entomology program will be presenting as part of the Global Change Forum, a first of its kind meeting of scientists at the NC Natural Science Museum.  We will be presenting on the impact & importance of spotted wing drosophila, pollination biology, and more!  See here for more information on this exciting event.

More information
Global Change Forum