Project objectives from proposal:
The objective of this project is to adapt an existing bird netting support system to support large expanses of insect netting to exclude SWD from mature highbush blueberries. A second objective is to determine how effective the netting is for preventing SWD from infesting blueberries at a commercially acceptable level throughout a long harvest season. ProtekNet 80 gram insect netting (.95mmx .95 mm) will be purchased from Dubois Agrinovation in Saint-Remi Quebec. One of the current problems with existing insect netting is that it is not available in wide widths to cover large areas. Dubois can have pieces of their 80 gram netting sewn together to create a 26 foot wide piece but larger pieces cannot be created – they are just too large for existing machinery to handle.
We will take two 26 foot wide pieces of the netting and combine them by rolling them around pvc pipe and then fastening them with existing greenhouse hardware that is used to attach roll up sides to purlins on greenhouses – see photo 1. PVC pipe and hardware will be provided by The Berry Patch. By fastening these two pieces together we will have an approximately 51 foot wide sheet of insect netting to apply on the entire length of the planting (250 feet).
I propose to test the efficacy of this netting in excluding SWD using two different support systems described below. One system is made of tall metal poles with PVC tees on the top of each post to facilitate movement of netting over and along the height of the posts. A 51 foot wide piece of insect netting will cover three rows of blueberries, while still leaving enough on the bottom to anchor. The other system is made of greenhouse hoops, set further apart within the rows. See photo 3.
The greenhouse hoop system worked extremely well for us with bird netting, and I suspect it will work equally well with insect netting, if not better. Two sets of bows, placed right beside each other, will allow me to rest the pvc pipe holding the seam of the insect netting in the valley between the two sets of hoops. This system will allow me to cover 3 rows of blueberries with one set of insect netting. Galvanized pipe, used as purlins in greenhouse construction will be used with the same greenhouse parts fasteners as in photo 1 to attach the insect netting at the ground level. The galvanized pipe is preferred due to its heavier weight and therefore, greater likelihood of weighting down the insect netting to prevent infestations from SWD getting in under the netting along the edges.
An entrance vestibule will be built for each of the two covered treatments, consisting of approximately a 4’x 4’x7’high area that will be attached to a “doorframe” of 4 x 4’s in the end of the netting. The vestibules will be anchored to the ground with 3 foot long pieces of rebar, and attached to the doorframe in the netting with hinged latches so that they can be removed when netting is not needed and stored under cover in a barn. The vestibule will also be covered with ProtekNet 80 netting. A vertical slit will be cut in the end of the insect netting in the middle of the doorframe entrance to the field, and a sheet of insect mesh will be attached to the top of the doorframe on the outside of the netting. This will provide multi layers of protection from SWD being able to infest the planting.
To perhaps visualize the entrance, one should visualize a walk in cooler that has the plastic strips inside a doorway to prevent cold loss. Workers will need to enter the vestibule, close the outside door of the vestibule, and then enter the planting itself by moving the curtain of netting to the side and stepping through the slit netting into the planting. The netting will be put up as the first variety of berries starts to show color, usually during the first week of July.
There will be three treatments.
Treatment one is netting applied over upright posts to cover 3 rows of blueberries.
Treatment two is netting applied over greenhouse hoops to cover 3 rows of plants.
Treatment three is an uncovered control (covered with bird netting only) that will be sprayed with Entrust or Delegate insecticide, rotated with appropriate effective materials for purposes of resistance management.
To measure the efficacy of the system, SWD traps consisting of an ampule filled with a fermenting solution of yeast, sugar, water, and whole wheat flour with a killing solution of apple cider vinegar, raspberry juice, and soap will be set in each treatment. On the recommendation of Dr. Greg Loeb, Professor of Entomology at the NYS Experiment Station, 2 traps will be placed in the front edge of each treatment and 2 traps in the back edge of each treatment. These traps will be checked weekly, solutions changed, trap contents recorded and charted over time. 90 ripe fruit per treatment will also be harvested weekly and examined visually for oviposition scars. Fruit will be collected systematically from the three rows distributed in each covered treatment. In the netted rows, each border row and the middle row will be sampled. In the control row, both rows will be used for fruit sampling. After visual inspection fruit will be put into salt water to confirm the presence or absence of larvae following well-established procedures. Twice during the season, once in the early part of known SWD presence (SWD in adjacent hedgerow traps) and once in the late season, fruit will be collected and sent to Dr. Loeb’s lab and reared out to confirm the presence or absence of SWD, and density of infestation.