White Netting in the Vineyard
by J.F. Pirro
To net or not to net usually isn't much of a question for producers growing fruits and berries that birds are fond of feeding on. However, what brand, size, shape, type and color of netting is a topic worth some industry debate when your harvest is on the line.
There's an increasing movement to use white side netting mostly in vineyards, and some argue that it's an improvement over the more typical black extruded plastic netting.
In general, fruit zone net - commonly referred to as side nets - is becoming increasingly popular with American wine grape growers looking to protect valuable grapes from hungry birds, while also avoiding the hassles sometimes encountered with the use of drape-over nets.
Is white the best?
Michael Schmidt of Spec Trellising, a family-owned and operated trellis supply company in Ivyland, Pa., thinks so. His company offers a diversified product line that includes everything growers need to trellis and train their vines and manage their canopies. While his focus is primarily on grape growers and the trellising of grapevines, Schmidt also works closely with growers of raspberries, blackberries, apples and other fruits.
While Schmidt says his company may have been the first in the country to sell white side netting, it hails from Australia and New Zealand. When he first began offering netting 12 years ago, he only offered white. Now he offers many options, but about 70 percent of the netting sold is white.
Available in different shapes and sizes, the smallest is triangular 4-by-5-millimeter netting, and the largest is a square 15-millimeter. Widths range from 31 to 53 inches for vineyard side netting. He also sells single-row and multi-row drape-over netting.
The white side netting is more popular and trending upward, mostly because the cost per acre is cheaper, he says. Growers can buy more netting material for less, they can access the fruit, and they don't have to worry about the vines growing through the top.
Schmidt is fair when explaining the advantages and disadvantages to white side netting. Among the advantages, he says the white netting does deter birds. "Many growers come back to us and say that with the white netting they don't even see birds anymore," he says.
On the negative side, it is white and does stand out as a bold visual in a vineyard, where black or green blends better with the crop. For some it's simply about aesthetics. "If you have a nice setting (and maybe use the vineyard for weddings for extra income), you may not want white," Schmidt says.
Perhaps the biggest obstacle to overcome for the efficient use of side nets is the amount of labor involved when applying or removing them.
As a matter of the difference between reflection and absorption, white netting also shades less than black. The smaller mesh nets are also harder to see the fruit through, especially if a grower is searching for disease. With the larger mesh netting, that's not as much of a problem.
At Blair Vineyards in Kutztown, Pa., Rich Blair is in what he terms his "third round" of netting trials in the last dozen years. He started out using an over-the-top product, and it was white, but he had trouble accessing his fruit and scouting for disease, and the netting often crushed the top growth.
He switched to black side netting and then to Schmidt's white side netting, the best he's experienced. On his 30 acres of vines, 60 percent are still in the black netting and 40 percent in Schmidt's white. It's been a slow, steady, long-term conversion over the last five years.
"I gave up on the over-the-top netting," Blair says. "It was too tough to get to the vines. With the black, the birds were getting in, hanging on and opening holes. With the white, it reflects so much light that it scares the birds, and they might not even see what's behind it. It's also more tightly woven, but is almost like Mylar, and so it moves and frightens [birds]."
The UV protection guarantee is an important bottom line factor. "You can't have netting with a four or five-year life span," Blair says. "This [white] is more like 10 or 15 years."
MaryJo Thaden of MDT & Associates in Minneapolis, Minn., says all brands of white net are not heavy (30 grams), and 30-gram net is also available in green. Growers who are using the white 30-gram material are doing so because of the longevity of the net, she agrees. "In that case, growers need to be sure they are getting 30-gram netting and not go just by the color," she warns.
In making color comparisons, she says opinions vary. "It's not scientific," she says. "I would not encourage growers to get one or the other based on color alone. Birds are wise to netting; I believe that they now recognize that netting means food!"
MDT sells black, green and white netting, and Thaden says that she has not had any feedback from growers that color makes any difference in deterring birds or causing more shading.
Other uses for white netting
In the mid-1990s, Carolyn McQuiston at Dawson's Orchards in Enon Valley, Pa., began covering her small blueberry plantings with black extruded plastic over PVC pipe frames. Much of the fruit was saved. It was sweeter, and picking was faster because the grower could lengthen picking intervals. Simply put, a greater density of ripe berries made the picking faster.
The downsides were that the lawn mower easily caught the netting and caused a mess, wrapping itself tightly around the blade shafts. Then, the birds seemed to rip holes with less effort. Also, the netting was hard to work with because it snagged on everything (bushes, framework and even pickers). "We used various methods to connect one piece to another and repair breaks, but none too successfully," McQuiston says.
Two years ago she bought a roll - $1,000 worth - of white netting. She didn't end up needing it on a newly planted field, so it sat for six months. The following spring, she found a use for it in the orchard's 60-year-old packinghouse as they got ready for the food safety audit. They used the netting to create a barrier for birds in the second floor of the building.
"The guys raved over how easy it was to work with compared to the extruded plastic," McQuiston says. "They attached the ends to PVC pipe in a wide doorway so they could slide it back and forth when we needed to access the second level."
That harvest season they also used it on a new field of blueberries and found it very easy to work with.
"I don't know if there were other factors, but after a short time the birds didn't even seem to try to get access, supporting the claim that the white color repels them," McQuiston says.
Under the previous system, she was always trying to corral birds to one corner to get them out of the packinghouse, but the switch to white netting resolved that issue.
"The dog was mildly disappointed because those birds were easy targets," McQuiston says. "Because of its ease and success, we ripped the old net off another field and replaced it, again being quite satisfied with the results. It was easier to pick under because it didn't snag one's clothing/hair like the old [netting] did. Another benefit was how the mower didn't seem to pick it up as easily, although I am not sure why. The girls seemed to be able to 'sew' it together quickly for repairs and connections. Although it was a lot of money to spend for the acreage [about 1 acre of blueberries], the roll went on and on and we still aren't through it."
The author has been published in national and regional magazines as well as daily and weekly alternative city newspapers. A gentleman farmer in Quakertown, Pa., he writes about people, social trends, historic preservation and 18th-century America, agrarian culture, land use, and sports and recreation topics.
Photos courtesy of Spec Trellising.