Grapevine Bird Damage Control

PROJECT BACKGROUND
Smoky Hill Vineyards and Winery is a family owned operation that consists of 40 acres, a portion of which are grapes for wine production. The business consists of the vineyard, winery, tasting room and events center. In addition to the vineyard owned by this operation, we utilize an additional 40 to 50 acres of grapes from contract growers.

Grape growing through wine making is done with sustainable practices. The operation utilizes cover crops and recycles as compost or other material(s) the waste generated.

PROJECT DESCRIPTION AND RESULTS

Goals:

1. To reduce or eliminate the crop loss and quality degradation associated with bird damage.
2. Reduce the labor input costs associated with crop protection. Determine all areas where cost savings can be realized.
3. Determine the relative effectiveness of three control methods.

PROCESS

1. Research the various methods of controlling birds. This process involved online and phone interviews with suppliers as well as other producers utilizing various methods.
2. Based on the research, two methods were determined to be the best to utilize in the study. The two were netting, which involved a traditional top applied net and a emerging “fruit zone” applied netting, and the used of deterrent sprays.
3. Two different test blocks were selected with each block separated into a control (no protection), sprayed and netted section. Top applied netting was evaluated against the fruit zone narrow mesh netting.
4. The methods were employed during the 2008 and 2009 growing season.
5. Relative data on loss and quality impacts were observed.
6. Labor costs were observed for their impact.

PEOPLE

There was no outside assistance on this project. The results were given during a workshop on May 16, 2009, available to anyone wishing to attend.

RESULTS

1. Considering the quality impact, there was a very notable different between the control blocks and the blocks that were treated. The best protection against the bird damage was realized with the fruit zone netting. There was not observed bird damage and thus no rot, mold or fungus transfer into the juices. The quality effect was large enough between the top netting and the fruit zone netting to create a marketable difference of $150 per ton or $500 per acre. For a vineyard that also is a winery, the impact of the quality is the single most important factor as it translates into the sellable price of the finished product and therefore can have additional gains or losses associated.
2. Considering the labor savings, the spray offered the lowest labor input. With spray, we realized a labor savings of over 50 man-hours per acre in 2008. It is very important to note that in 2009 the spray had to be applied 3 times to be effective. This was likely due to the temperature and moisture difference in 2009. All be it not a typical year (frequent rains after fruit verasion and lower temperatures in the mid 80’s), the effectiveness of the spray was very low in 2009. It required 3 applications versus one in 2008 and still had damage. When comparing the top applied netting to the fruit zone netting a labor savings of approximately 40 man-hours per acre was realized.
3. Considering the capital investment, the spray would save between $800 and $1200 per acre, but does require a blast sprayer and tractor. These things are typically available at all vineyards over 5 acres.
4. Considering the input (non-labor) costs, the spray control can add as much as $555 per acre. The cost for either of the net options is under $25 per acre.

DISCUSSION

This project revealed the following results and conclusions:

1. The current practice of top applied netting did not show to be the best method for a long term solution. This method has nearly the highest capital requirement, the highest labor requirement and did not have the highest level of control. Some quality deficiencies were found with this method. As well the labor required for the net installation comes during a very important and busy time.
2. In 2008 the spray looked very effective. There was only one spray required and the effectiveness was very good. Considering all costs, this method would break even with the costs of the nets in 6 to 7 years. The effective life of the top netting is 7 to 10 years. Therefore the spray would be chosen based on the ease of use and reduction in capital spending. 2009 however was very different. With the excess rains the treatment had to be reapplied two times and therefore making the netting payback around 2 to 3 years. The conclusion here is if the region is one that is under drought or does not have rain pressure late July through early October the spray may be the best choice.
3. The fruit zone netting was by far the superior choice. This method had no bird damage either year. The fact that the netting is applied only the first year, means there is a savings in labor each subsequent year. It is very important to note that the fruit zone netting used is one that has a 4mm by 7mm mesh opening. There are other nets that are marketed as “fruit zone”, but they have a much large open size. The result is that canes will grow through the nets creating the same problem experienced with the top nets. Because of the tight mesh, these nets eliminate the need for catch wires on Vertical Shoot Positioning (VSP) canopies. This was tested and found true. This results in capital cost savings of $300 per acre for VSP wires. Other benefits studied and affirmed with this netting was that the small mesh helped to shade the fruit and made the pesticide and fungicide sprays more effective. The shaded fruit helped to make the fruit ripen at a higher quality.

The final conclusion for the study is that the fruit zone netting is the best option for the VSP canopy. For the top wire canopy the existing top netting is the only option during wet seasons and the spray maybe the best method during dry seasons. Another study for the efficiency of the top netting currently used compared to the small mesh netting would be of interest. There would be higher capital costs (almost double) compared to existing, but the labor savings, quality improvement and longevity may provide a payback for the improvement.

PROJECT IMPACTS

The solution to the problem, at least for VSP is the fruit zone nets. They will provide both the economic savings for labor of around $400 per acre per year and given the savings of the wire, the capital costs would be equivalent to the existing top method, the net life span is expected to be 3 year longer and the quality impact will be an advantage.

OUTREACH

The main method of getting the results out on this project was a workshop. The workshop was conducted through the Kansas Grape Growers and Winemaker Association. The workshop was publicized through the email list service used by the growers and wineries in the Kansas area. A copy of the presentation has been attached to this report.

Additionally this presentation has been (and will continue to be) made available in electronic form. Those that could not attend have received copies after requesting it by email.

PROGRAM EVALUATION

The program was very effective. From the initial application through the final report there has been support and easily obtained answers through the SARE program. This has been a lot of help in this our first project under this program.

Norman Jennings PowerPoint Presentation, May 16, 2009 Workshop