NC State summer vineyard tour - 27 July

NC State University grape experts will be leading a tour of muscadine and vinfera vinyards on 27 July. We'll be hosted by Cauble Creek Vineyard and Morgan Ridge Vineyard, both in Rowan County.

 I will be discussing the Grape Root Borer Volunteer Monitoring Network (GRB*VMN) and kicking off 2012 monitoring!

 Preregistration is required by 24 July. See the program below for the registration form and details on the other presenters.

Why are monitoring sites only listed by county?

You may have noticed that site names for the SWD*VMN are coded by county followed by a generic number.  I have also shared monitoring data online for the Grape Root Borer*Volunteer Monitoring Network (GRB*VMN) and for blueberry insect monitoring programs run by my laboratory, again with sites identified to the county level. I had a request via the comments on this blog for more detailed location information for one of our SWD*VMN monitoring sites. Because of this request, I wanted to clarify that it is my policy not to provide any geographic information about trapping locations below county.  The reason for this policy is two fold:

1. County is a established level for displaying insect (or other invasive organism) detection information.  See the National Agricultural Pest Information System for an example, and

2. All of our monitoring networks represent a patchwork of public & private and commerical & non commerical land. Because some commerical fruit growers have generously to allowed us, county extension agents, or others to trap on their land or have contributed their trapping data to our networks, we do not want to risk any potential harm to their business by sharing more information than necessary with the public.

The purpose of sharing insect monitoring data online is to provide information growers, homeowners, and other stakeholders can use in making management decisions.  It is not intended to replace site specific monitoring by growers or homeowners.  Just because an insect is being trapping in your county does not mean that it is present on your farm. Knowing exact trapping sites within a county would not change this.  Insect activity in your county does suggest, however, that it would be wise for you to go out and check your plants. Insect trapping data is also not intended for use by regulators or consumers.  Just because adult insects are active at sites does not necessarily mean that damage to crops is occurring.

Eagle eyed readers may have noticed that I will occasionally name a site when posting about trapping data.  I only do this for sites at state and/or university run research stations, like New Hanover 1, which is located at the Horticultural Crops Research Station near Castle Hayne, NC.  Because research stations are non commerical operations, identifying these sites does not compromise grower cooperator privacy.

Grape Root Borer*Volunteer Monitoring Network trapping data now available

The Grape Root Borer*Volunteer Monitoring Network (GRB*VMN) has been up and running for a month, but the first, substantial trap captures occurred last week. The network consists of 10 locations in 7 North Carolina counties. Trap captures from these sites will be available here through the end of October, when the grape root borer flight is expected to end.

2011 GRB*VMN sites. Sites are only identified to the county level and assigned a number for record keeping purposes when there are multiple sites per county.

Monitoring locations and trapping data are listed below, from east to west:

Jones County 1

Rowan County 1

Rowan County 2

Davie County 1

Yadkin County 1

Surry County 1

Surry County 2

Surry County 3

Wilkes County 1

Haywood County 1

The highest number of trap captures is currently in Davie County with a few other locations catching a few moths. It is interesting that our flight appears to be occurring so late in the year, since reports of moth captures begin in July last year. We are monitoring the grape root borer flight in North Carolina to better understand when and where our highest populations occur. This information is important when making grape root borer management decisions, in particular whether or not to use currently labeled pesticides, which must be used either 30 days before harvest or after harvest. If you are interested in monitoring grape root borer yourself, see here for more information.

More information Do it yourself - Grape root borer monitoring

Do it yourself - Grape root borer monitoring

Tomorrow, June 26, I will be kicking off the 2011 Grape Root Borer Volunteer Monitoring Network (GRB*VMN) at the NC Winegrowers Association summer picnic. I will be distributing trapping kits to volunteer growers and demonstrating trapping methods. For grape growers interested in monitoring for grape root borer who cannot attend the meeting, this post details how to monitor on your own. If you are interested in participating in the GRP*VMN, please contact me for more information.

The traps I use are available from Great Lakes IPM* and pheromone lures can be purchased from Arbico-Organics*.


Grape root borer (Vitacea polistiformis (Harris)) is potentially the most significant pest of grapes (both muscadine and Vinfera) in the southeast.  Larvae have a 1 to 2 year life cycle, which means that injury, in the form of weakened and dying vines, often does not present for several years.  Many of the Vinfera vineyards in the Carolinas and Georgia are reaching the 8 to 10 year mark, the time at which I anticipate grape root borer injury to become more apparent.


The GRB*VMN has two purposes:
1. To determine the density, range, and seasonal biology of grape root borer in North Carolina.  In other words, to find out how many moths we have in our vineyards, which vineyards they are present in, and at what time of year they are active.
2. To give NC grape growers the skills to monitor for grape root borer and make management decisions based on monitoring information.


To accomplish these goals, we will train grape growers throughout the state to monitor for grape root borer adults on their farms and share their data through this blog.


Monitoring methods
We will place 4 universal moth traps per vineyard.  Ideally, we will place these traps each in a different variety (if present).  Within variety blocks, traps should be placed in low lying, wet areas, since these are at the highest risk of grape root borer infestation.

Grape root borer trap components. From left to right: hanger, trap top, trap lid, pheromone container (front), pheromone impregnated septa (packet, front), pesticide kill strip (red, front), and trap bottom (back).

Traps should be assembled as follows:

Pesticide strips placed in trap bottom.

Pesticide strips are used to kill moths once they enter traps. No pesticide is present outside the traps, and therefore, these traps can be used in organic systems.  Pesticide strips should only be handled with nitrile gloves.

Trap top attached to bottom.

Trap tops snap onto to trap bottoms.

Trap lid added to trap top.

Trap lids keep rain and other debris out of the bottoms.

Grape root borer pheromone impregnated septa.

Grape root borer pheromones are impregnated onto rubber septa and remain attractive for an entire field season.

Pheromone lure placed in pheromone container.

Pheromone lures are placed into lidded containers.

Assembled trap.

The pheromone container is inserted in the trap lid and hangs into the trap opening.  Moths are attracted to pheromone lures and fall into the trap bottom where they are killed by the pesticide strip.  Hangers are attached to trap lids, and traps are hung from canes or trellis wires.

Assembled grape root borer trap

Traps are checked weekly  and moths are counted.  Pheromone lures are attractive at a long distance to male moths, and attractive at a short distance to females, so both sexes may be present in traps.  Grape root borer moths resemble wasps but differ in that their wings are black and they lack the thin "waist" of wasps.  After a few days in the traps, moths may appear darker brown (see below).

Mating male (left) and female (right) grape root borer moths. Photo: University of Kentucky.

Female grape root borer moth one week after collection.

While the grape root borer pheromone is relatively specific, it will attract one related species, the squash vine borer.  However, these moths are bright orange and black and easily distinguished from grape root borer.  Other insects found in traps may include beetles and small brown moths, but these should also be readily distinguishable from grape root borer moths.

Mating male (left) and female (right) squash vine borer moths. Photo: University of Minnesota

Data collected by the GRB*VMN will be entered online weekly and will be shared here, beginning the first week of July.

*Does not imply endorsement of named vendors over other options.

More information
NC Winegrowers Association - Summer Picnic

Grape Root Borer Volunteer Monitoring Network (GRB*VMN) Seeking Participants

Grape root borer (Vitacea polistiformis) adults. Photo: University of Florida

I was extremely pleased with the success of the spotted wing drosophila (SWD) volunteer monitoring network in 2010. While fielding lots of questions about grape root borer last summer, I realized that this insect would be a great fit for a volunteer monitoring program. In many ways, grape root borer is an even better candidate for a volunteer monitoring program than SWD. The adults are easy to identify, pheromone lures are reasonably specific, and there is only 1 possible generation in North Carolina.

Why do we need a monitoring network for grape root borer?

We have huge gaps in our knowledge of this pest in North Carolina. Many of these gaps stem from the fact that grape root borer has a 1-2 year life cycle (depending on temperature and location in the state), making it hard to do research on. We need to understand the extent and size of our grape root borer populations relative to our vineyards, and we need to understand the seasonal biology of grape root borer (when they begin emerge as adults and for how long this emergence lasts). Both of these needs require a large scale monitoring effort over a wide area. I cannot do this type of research by myself, but I can train interested grower and non grower volunteers to monitor a few locations in their vineyards. If we attract enough volunteers, we can build a powerful data set in 2 years that will allow us to maximize future research efforts.

If this sounds interesting, see below about how to get involved!

What is the Grape Root Borer Volunteer Monitoring Network (GRB*VMN)?

GRB*VMN is a group of North Carolina grape (muscadine and bunch grape) growers and others who are interested in increasing our understanding of grape root borer, an important insect pest of grape vines. We are recruiting volunteers from throughout the state who currently grow grapes.

Why should I join the GRB*VMN?

We will determine the presence and emergence timing of grape root borer in North Carolina grapes. This information is important for developing management programs for grape root borer. We currently only have 1 tool (a pesticide) available, and its use restrictions limit its effectiveness. We need more information about grape root borer biology to support the development and registration of more tools, including non-chemical options.

What will I get from the GRB*VMN?

You will receive:

4 GRB traps & pheromone, Training on trapping and GRB identification, Access to data from your farm and all participating farms (through this blog and regular email alerts).

What do I need to do to participate in the GRB*VMN?

You must agree to check traps weekly from May through October & enter data online. Checking traps should take no more than 1 hour per week.

More informationContact Hannah Burrack for more information on the GRB*VMN and how to get involved!

I will be at a grape field day in Surry County tomorrow (February 18th) to discuss GRB monitoring and recruiting volunteers for the GRB*VMN. See here for details and location.