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Tuesday, September 22, 2009

An emerging pest, on the march!

Spotted wing drosophila on raspberry in Northern California. Males have spots on the ends each of their wings, while females do not. Image from the UC ANR Strawberry and Caneberry Blog, courtesy Ed Show.

Formerly known as the cherry vinegar fly, the
spotted wing drosophila (Drosophila suzukii) has rapidly progressed from recently detected invader to significant pest of fruit in California. The fly was first detected in fall 2008 and was confirmed in backyard and commercial cherry plantings in spring 2009. Experts in California believe it has been present for at least a year prior to that detection. On August 4, 2009, the spotted wing drosophila was detected in Hillsborough County in central Florida.

What makes the spotted wing drosophila a concern to growers and entomologists alike is the fact that its serrated ovipositor (egg laying devise) allows it to attack sound fruit. Of the nearly 1500 known drosophila species, only 2 are pests of sound fruit, one of which is the spotted wing drosophila. Most other drosophila flies feed on the microorganisms that inhabit rotting fruit or plant tissue, and therefore are not typically crop pests.

Any soft fruit is likely at risk for damage by this pest, which includes caneberries, strawberries, peaches, grapes, blueberries, and figs. Research in California indicates that the fly completes a generation in approximately 2 weeks. Infested fruit appears bruised from the outside, and small (1-2 mm) larvae feed internally.

Because they are present in Florida, it's only a matter of time before the spotted wing drosophila makes it way to North Carolina. I will be working with county agents this winter to establish a monitoring network in high risk counties. Please contact your county agent or myself if you suspect spotted wing drosophila damage in your fruit.

You can find more information on spotted wing drosophila at the following links:

Monday, September 21, 2009

Blog role

In updating posts and catching up with email this morning, I came across a few blogs I hadn't seen before. Some were so impressive I decided they were worth sharing. I am also including links to some the blogs I regularly visit.
In the field: An NCDA blog with great, regular updates on agriculture, marketing, and outreach.

Deep Fried: T-minus 30 days and counting...this is the official blog of the NC State Fair. I know I, for one, will be putting something together for the Deep Fried ambassador contest.

Western NC Vegetable and Small Fruit News: Sue Colucci is an area horticulture Agent in western NC, and her blog is what convinced me that this effort was worth trying out.

NC State Insect Museum: Colleague Andy Deans and crew maintain a funny, informative blog on all things entomological. Keep an eye out for their annual insect haiku contest and the NC Entomological Society photo contest, just announced!

Myrmecos: I recently rediscovered a grad school classmate's website. Alex Wild is now at the University of Illinois Entomology Department and is also an accomplished photographer who archives his images here.

It's wine and grape appreication month!

Sunbelt grapes (a V. lubrusca variety similar to Concord) ready to harvest at Kildeer Farms in Kings Mountain, NC on August 5th. These even ripening grapes are an addition to grower Ervin Lineberger's fresh market muscadines and seem to do well in NC. They're really tasty, too, but they ripen uniformly and are only available for about a week in August!

I posted earlier this month about upcoming muscadine grape events, but I somehow missed the announcement that September is Wine & Grape Appreciation month in NC! I can think of several good ways to celebrate!

Saturday, September 19, 2009

Answering questions about hops in NC

Early season hop yard in the Yakima Valley, WA (image via Wikipedia:

There's been a noticeable buzz about hops in NC lately, and I have been receiving more questions about pests and management. I am typically conservative when comes to recommending that growers plant a crop about which we still have a lot to learn (from culture to market demand), but several small growers have vines in the ground and have seen pests appear this season. If these growers persist and other join them, I'll be ready with as much help as I can provide. The biggest challenge for many of these growers will be their desire to produce hops organically--there are good market reasons for this decision, but many of the pests of hops will be particularly hard to manage organically.

Fortunately, a friend at WSU works some on hops and has been an early resource, but as he pointed out in our first conversation about hops--we have this thing here called humidity that they don't content with in the high desert. Because NC growing conditions are so different from the places where hops are typically produced, we need to be careful when adapting management recommendations from Washington and Idaho. We may have pests they don't and visa versa.

I do have a sense of what was out there this year based on clinic submission and emails, and some them are the usual suspects. A short list of what to watch for on hops:

Twospotted spider mites: TSSM (as I like to call them) are polyphagous pests. This means they feed on lots of plants from strawberry to tomato and from Japanese maple to hops. Mite feeding causes leaf stippling and yellowing with severe infestations resulting in defoliation. This leaf injury then can impact yield. Idaho recommendations suggest treating when mites reach 1-10 per leaf. Because organic materials behave differently, I would err on the more conservative side. I hope to gather some data on predatory mites in hops next summer, and I think these may be a viable option. I am not aware of any work done on pred. mites in hops, so I can't say what they real benefit would be yet. Organic pesticides are marginal against mites and their use will be challenging with the large hop canopy (an air cannon sprayer would be a good investment for the serious grower).

Hop aphid: Hop aphids do occur in NC, and they are a pest both because they vector disease (it's unclear how big an issue these diseases will be here) and because they feed in hop flowers--the harvested part of the plant. Aphids and the sooty mold they produce render cones unmarketable, which makes them a very serious pest. Aphid feeding behavior also makes them very hard to control completely in an organic system (there are very effective conventional controls). Biological control agents typically only move in when aphid populations are established and do not provide sufficient control. Organic pesticides need to contact aphids to kill them, since they do no move within the plant. I suspect the plan for organic aphid management will be to "treat early, and treat often"--a situation we typically try to avoid.

Leafhoppers: I have heard lots of complaints of early season leafhopper populations in hops, but I haven't seen any samples. This mean that I don't know what species we're dealing with or the damage it's creating (if any). Leafhopper do not appear to be hop pests in the western US (where most commercial hops are grown), so this a problem we will have develop information on here.

I'm keeping an ear to the ground to see where hops go in NC, and I'll keep posting.

Thursday, September 17, 2009

Muscadine Field Day a Success!

The Muscadine Field Day at Castle Hayne had a great turn out Wednesday! Even though advertising budgets are tight and the field day was only publicized electronically, about 70 growers, agents, NCDA & NCSU attendees heard talks from Jim Ballington, Barclay Poling, Connie Fisk, me, and Bill Cline.

Poling discussed pruning technics in muscadines (also in the NC muscadine production guide--which will be getting a much needed update this winter).

Bill Cline discussed late season diseases (mainly ripe rots) and some problems that are NOT disease related like the injury on these Carlos, which appears to be due to a broad mite. There's always something new to learn about!

Muscadine grapes have the fewest severe insect threats of all the crops I work on. The most common questions I get in reference to muscadines this time of year are about bees and wasps on ripe fruit. Most growers and homeowners want to know if they can treat these bees and wasps, which I highly discourage. I did manage to find some other interesting insects in the variety block (while conducting a very scientific flavor comparison).

The upper photo show a leaf roller larva (these are caterpillars which feed on leaf tissue), and the bottom photo is likely a grape berry moth larvae found inside a grape. Although grape berry moth (GBM) can be serious pests of grapes, they are generally rare in NC, and Bill says this is first he's seen in this block. I suggest that growers concerned about GBM use pheromone traps to monitor whether they are present before deciding whether to treat.

No field day would be complete without dessert! Connie provided ice cream with muscadine dessert sauce from Duplin Winery.

I'm also looking for a good grape for my yard, and Southern Home (an "ornamental" muscadine) is at the top of my list. They have interesting foliage--fig leaf in horticultural parlance--and sweet aromatic black fruit. Now to find a spot to plant one.

What does IPM mean?

It's in the title of this blog and it's something I spend most of my day thinking about, but when I talk to folks outside the university system, I'm not always sure IPM is understood as well as we think it is. This year is the 50th anniversary of one of the most influential papers in entomology (and agricultural biology) and the paper that introduced the integrated management concept. "The integrated control concept" by Stern, Smith, Van Den Bosch, and Hagen was published in 1959 in the University of California journal, Hilgardia. Integrated control in this paper was defined as "pest control which combines and integrates biological and chemical control". While revolutionary for the time, this definition is somewhat limited in comparison to how we think of IPM today (it's not just biological and chemical control).

In the last 50 years, the term "control" has been replaced with "management" to acknowledge the fact that we're a player in agricultural systems, not necessarily in charge.

Other definitions of IPM include:
EPA: IPM programs use current, comprehensive information on the life cycles of pests and their interaction with the environment. This information, in combination with available pest control methods, is used to manage pest damage by the most economical means, and with the least possible hazard to people, property, and the environment.

UC IPM: Integrated pest management (IPM) is an ecosystem-based strategy that focuses on long-term prevention of pests or their damage through a combination of techniques such as biological control, habitat manipulation, modification of cultural practices, and use of resistant varieties. Pesticides are used only after monitoring indicates they are needed according to established guidelines, and treatments are made with the goal of removing only the target organism. Pest control materials are selected and applied in a manner that minimizes risks to human health, beneficial and nontarget organisms, and the environment.

Radcliff's IPM World: Integrated pest management can be defined as the practice of preventing or suppressing damaging populations of insect pests by application of the comprehensive and coordinated integration of multiple control tactics.

All of these definitions have the same core and get their message across with varying degrees of brevity, but maybe because I like things catchy, I found myself wanting a different way to explain IPM when I spoke to growers and the public. Last year, while driving (which I do a lot for work) I thought about the 3 word that really mean IPM to me: Minimize, Monitor, and Manage.

These broad action categories crystalize the concepts in the definitions above (and many, many others). We should first minimize the likelihood of pests (insect, disease or weed--IPM covers the whole range--it's not insect pest management!). We minimize by selecting good cultural practices: resistant varieties, water management, planting date, nutrition, and many others. We then need to monitor our plants, for pests and for general health. Sometimes these monitoring programs are systematic, sometimes they are as simple as walking through your feed and noticing what's going on. Monitoring also includes correct ID of pests--if you don't know what you have, you can't know what do about it! Monitoring (or knowing a pest population density) is also important when using thresholds. Typically, pest populations have to reach a certain density before you start loosing money--treating before that threshold actually costs more than the good it does. Finally, management. This is where Stern's ideas come back. Management options include biological, cultural, and chemical. As a rule chemical control should be our last choice and should be used in a way to cause the fewest additional problems.

Friday, September 11, 2009

A note on pesticide recommendations

Hands down, the most common question I am asked as an extension specialist is "what do I spray to control X?" I knew this would be the case from the get-go, and I enjoy helping growers and the public make good decisions about what, when, and how to use pesticides on their crops. That said, this blog will not be a forum for making those recommendations. Pesticide labels change frequently and vary by state. Because I don't know where you (hopefully there's a you) are from, what's available in NC may not be available or legal for your use. NC residents can refer to the NC Ag Chem Manual for recommendations for specific crops or can contact me directly for more detailed information. Interested parties outside NC are welcome to also contact me, and I will do my best to put you in contact with the right folks for recommendations in your state.

Caterpillars in blueberries (and other woody perenials)

Redhumped caterpilars (Schizura concinna), Lacy L. Hyche, Auburn University, Bugwood.

As weather really starts feeling like fall, caterpillars are showing up in NC blueberries. Most common and noticeable are redhumped caterpillars and yellownecked caterpillars.

Yellownecked caterpillars (Datana spp.), from Debbie Roos, Growing Small Farms:

I had a phone conversation about these insects with Bill Cline, blueberry and muscadine pathologist, immediately preceeded by an email from Benny Bloodworth, his technician. Both had the same question: what are these caterpillars and what should growers do about them?

Both species of caterpillars can aggregate when feeding and large populations can result in defoliation of the plants they are feeding on. The real question about what to do depends on the grower. Most large, commerical blueberry growers apply fall treatments for sharpnosed leafhoppers at the end of September or the beginning of October. Some pesticides used for leafhoppers will also effect caterpillars. If a large caterpillar infestation is present this time of year, one of these materials should be selected as the leafhopper treatment of choice. See the NC Ag Chem Manual for more information.  A note on pesticide recommendations.

Organic management is more challenging. There are effective organic controls for caterpillars (a lot of them), but there are little to no materials for leafhoppers. As I mentioned when talking to Bill today, organic blueberry growers are going to have to think differently about their production system than conventional growers. It will not be possible to just take a "spray schedule" and translate it into organic pesticides. These growers will need to maximize cultural management (in this case removing infested plants immediately upon noticing infection) and monitor carefully for pests because organic pesticides behave differently than conventional ones and must be carefully timed to be effective. Of course, conventional growers should be monitoring pests and minimizing pressure via cultural control, too! My IPM mantra is minimize, monitor, and manage, which I'll address in more detail in a post over the weekend.

Thursday, September 10, 2009

Tis the season for muscadines: upcoming events

A late fall shot from 2007, the last muscadines of the season hanging in there!

It's less than a week until the muscadine field day, and other muscadine events are also on deck this month. The Castle Hayne Research Station will host NCSU's annual Muscadine Field Day on Sept. 16. Morning sessions will be devoted to cultural, disease, and insect management presentations (expect lots of hands on information from me!). Following this talks, we will tour the station's muscadine trials and have the opportunity to taste test selections in the variety trial (always my favorite part).

For those of you that can't wait until next week (or can't make the trek to Castle Hayne), the State Farmer's Market in Raleigh is celebrating Grape Day on Friday, Sept. 11th. Rounding out the month, the NC Muscadine Festival will take place Sept. 26th in Kenansville, NC.

Connie Fisk, NC Extension Associate for muscadine grapes, maintain a great website with this information and more.

BugFest this weekend!

The country's largest insect themed event takes place this Saturday, Sept. 12th at the North Carolina Museum of Natural Sciences. This year's theme is butterflies and moths, and will feature exhibitors from NCSU's Entomology Department, among many, many others. Exhibit information and more can be found at the BugFest website.

NC Entomological Society Membership Drive Underway

The annual North Carolina Entomological Society Membership drive is underway now! This organization brings together entomologists from throughout North Carolina at our annual banquet, November 6, 2009. This year, our plenary speaker will be NCSU's own Rob Dunn, who's recently published book Every Living Thing is a fascinating read for scientists and non scientists alike. We are trying to broaden and invigorate our membership to include entomologists (and amateur insect enthusiasts) from throughout North Carolina, not just those in proximity to Raleigh. You can learn more about the society, our activities, and find membership information at the NC Entomological Society website. (2006 NC Ent Society Best in Show Insect Photo Contest winner, photographer: Bill Fisher)

Sunday, September 6, 2009

The changing face of extension

NC Extension is under going major shifts, including the retirement of many of our most experienced and knowledgeable agents. Among them, Karen McAdams, Orange County NCCE agent, who retired at the end August. The Raleigh News & Observer has a great article on her career, linked above.

Karen presented as part of an extension seminar taught by myself and Mark Abney in spring 2009, and her experiences had a real impact on the students. She has been a real asset to NC extension, and will be missed!

Linnaean games practices start Sept 8th!

The NC State Linnaean Games Team after winning the 2009 SEB ESA tournament and earning a spot in the national competition.

After a great organizational meeting last Thursday, regular practices for the NC State Linnaean Games team will begin on Tuesday Sept. 8th at 1pm in Gardner Hall. We will also meet Thursdays at 5pm, also in Garnder. All students are welcome, and encouraged to attend. The National ESA meeting is Dec. 13-16 in Indianapolis, IN, where the Southeastern Branch champs (NCSU) will compete for the national title.

The department Linnaean Games tournament will be Dec. 10th--more details to follow. Wondering what the Linnaean Games are? Check this out.

Late season tobacco pests pop up again

Tobacco flea beetle damage on an upper stalk tobacco leaf, August 20, 2009.

Last summer, several growers (mostly large) reported flea beetle, and to a lesser extent, aphid injury on partially harvested tobacco. This summer, we are again seeing patchy incidences of heavy flea beetle feeding on plants held in the field. This feeding is most prominent on the lowest leaves but has shown up on the entire plant. Because this is often the most valuable portion of the plant, growers are understandably concerned about the yield and quality impacts of flea beetle feeding. We lack good thresholds for late season injury, and I am particularly concerned about additional pesticide use so close to harvest.
Tobacco flea beetles congregated at the top of a tobacco plant, August 20, 2009.

Recently, a PhD student, Richard Reeves, has joined my lab and will be addressing this and other questions pertaining to thresholds for insect injury in tobacco. This work will begin in earnest in 2010.

For the time being, there are treatment options, but they should be used cautiously on a case-by-case basis.

Friday, September 4, 2009


After years of resistance, I am finally expanding my online presence to include a more rapid communication tool, this blog! I will be posting about once daily with current topics and events in the ever changing world of integrated pest management!