Growing & Winemaking


Grapegrower Interview: Hank Ashby

March 2011
by Laurie Daniel

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Located in the hills southeast of Paso Robles, Calif., French Camp Vineyards was developed in the early 1970s by the Miller family, which also owns Bien Nacido and Solomon Hills vineyards in the Santa Maria Valley and two custom-crush wineries on the Central Coast. With more than 1,200 acres under vine, French Camp is noteworthy not only for its array of nearly 30 grape varieties but also for its heavy use of sophisticated mechanical farming techniques.

Overseeing French Camp is vineyard manager Hank Ashby, who has been there since 1986. Ashby, whose family raised Concord grapes in Missouri, studied engineering at the U.S. Naval Academy and the University of Missouri-Rolla. He has used that engineering background to develop new equipment and techniques for vineyard mechanization.

Wines & Vines: You’ve been experimenting with various methods of mechanical farming at French Camp since the early 2000s. Why is that, and what were some of your early experiments?

Hank Ashby: We started experimenting with mechanical pruning in 2001. This was only two rows, because the procedure was risky. We had large spur positions on a lyre trellis, and we used a homemade sickle strong enough to cut through 2-inch wood. The idea was to prune closely and rely on regrowth suckers to have enough buds for a crop. To our surprise, the vines behaved normally with an average crop and average new growth. I was afraid that there would be a very low crop and vegetative growth because the quality of wood left was very poor.

Bob and Steve Miller (the owners of French Camp) had asked me to investigate the concept of mechanizing various handwork operations. They anticipated labor shortages in the future. We were already machine harvesting part of the vineyard. I talked to Dr. Justin Morris of the University of Arkansas, who developed the Morris-Oldridge system of mechanizing grape production. Tom Oldridge was an Arkansas grapegrower and inventor who worked closely with Dr. Morris.

The M-O system is a method that mechanizes various hand operations but also changes the timing of various operations. We bought a machine built by Oldridge from California State University, Fresno, where they had been experimenting with the system. It consists of a mast that mounts on the front of a tractor and an arm that extends to the right, over the row. It has about 40 different attachments. We purchased a pruner for a high wire cordon, a leaf remover, an implement for breaking off suckers in the middle of a divided canopy and three different types of fruit-thinning devices. We hired Tom Oldridge as a consultant, and he built a prototype shoot thinner. We did six experimental plots—Cabernet Sauvignon, Chardonnay, Sangiovese, Syrah, Merlot and Zinfandel—and made wine from both the hand-farmed and machine-farmed fruit. All the fruit was handpicked, and there were no significant differences in the wines.

With the M-O system, the pruning is done during the winter, with a rough follow-up leaving about double the number of fruitful buds as desired. Then at 6-to-10 inches of growth, depending on variety, we shoot-thin. Carefully counting shoots and clusters, we leave about 130% to 140% of the desired crop. This gives the grower a 30% to 40% overload through bloom and through much of the frost danger in spring. This can be a huge advantage in the event of a frost or a poor set due to cold, rainy weather.

After berry set, we count the berries on several clusters and establish a cluster weight using berry weights taken from previous harvests. Now you can determine your potential crop load and your need to fruit-thin. If there is a need to fruit-thin, that should be done during lag phase, when the berries are about half-size. This usually happens around the first of July, which gives the grower plenty of time to leaf, if desired, or brush the bottom of the cordon to remove suckers.

When lag phase arrives, we fruit-thin, if necessary. A damage factor should be figured in the formula. The formula changes with different thinning implements, grape variety and a multiplier that is determined by the berry weight that day versus historical harvest berry weight. If someone is considering using this system, it is essential to have this historical data about berry weight.

W&V: What improvements have since been made to the equipment?

Ashby: Oxbo International bought the patent for the M-O system and the equipment from the University of Arkansas. We had seen that to go to the next step, we would need to divide responsibilities to avoid operator fatigue. Oxbo engineered a trailer called the vMech, which had three seats and was pulled by a tractor. Two seats were occupied by operators, and the third seat was for a supervisor. This way we could do two rows at a time, and one person could observe mistakes, etc. The equipment operators did not have to worry about driving the tractor. It was set up with lights so some jobs could be done at night. The shoot-thinner, which is a perpendicular spinning wheel with flexible plastic paddles, was improved with paddles that were more durable. Many changes were made to the original implements, mostly in an effort to make them easier to operate and more durable. The leaf-removal system, for example, has a totally new design that does less berry damage. Ground radar has been added that will automatically slow down or speed up implement RPMs when ground speed is changed. A new shaker for fruit thinning is still in the R&D phase.

W&V: What was your role in improving the equipment?

Ashby: I first drew the concept of a trailer with a self-leveling mast. Oxbo took the concept, changed the two masts to arms and added various safety changes. I went to the Oxbo factory in Clear Lake, Wis., with Tom Oldridge a couple of times to help decide where to put the seat and controls.


What’s next for vineyard technology

The technology of vineyard mechanization is continually advancing, so Wines & Vines asked French Camp Vineyard manager Hank Ashby what sort of changes he sees on the horizon.

“In the future,” Ashby says, “I think we will see more multi-row farming. I think sensors will be developed to ‘read the wire’ and keep implements on track.”

He cites the increased use of global positioning systems as an example. “GPS tells where the implements are in relationship to the location of the cordon or row,” Ashby says. “There are already over-the-row tractors that can spray up to five rows of grapes. If the computer in the tractor says that one of the rows has already been sprayed, it will shut off the sprayer for that row. GPS can be used to create a soil map that tells the computer that this area needs to be pruned more or less severely because of soil differences.”

Bar codes and optics could also figure more prominently, he says. “Bar codes could be used to tell the computer specific information about that row; for instance, the rows have been lengthened and the last 30 vines are five years younger,” he says. “Optics could be used to monitor how much shoot density there is behind the shoot-thinning equipment or how much fruit before and after fruit-thinning. This information could be automatically sent to the computer, and the computer could adjust the equipment accordingly.”

W&V: What reaction have you gotten from the wineries you supply grapes to?

Ashby: The winery reaction has been very enthusiastic. All the wineries involved agreed to purchase the grapes for the same price as when we hand-farmed, or they requested that we switch their acreage to machine farming. This usually was because they liked the balance of fruit-to-leaf ratio, and they knew that some day the labor shortages would force these measures. In 2003 we started doing production acreage. We bought two vMechs and farmed more than 450 acres. In 2004 we bought a third vMech and jumped to 800 acres. In 2007, we bought our fourth machine. (Oxbo now calls it the Korvan 2220.)

We think that Merlot is actually better with machine farming. I think that sometimes the period of vine overload between berry set and fruit thinning produces a smaller berry size. This only works in the years when fruit thinning is necessary. It is the same concept as deficit irrigation, only the grower doesn’t have to deplete the deep moisture in the soil.

W&V: What are the advantages to mechanical farming?

Ashby: If a grower routinely shoot-thins, leafs and fruit-thins when needed, he can save up to $1,500 per acre. The savings are great, but the most important advantage is the built-in “insurance policy” of having 200% crop potential until late April (shoot-thinning), then 130% to 140% from April to July (through bloom). There are many things that can happen that we can’t control during this time frame.

We were able to replace 60 workers with each vMech. The crew of each machine is three operators and two counters for shoot-thinning and fruit-thinning.

W&V: What are the downsides?

Ashby: To mechanically farm, you must first have a mature vineyard that is fairly uniform. The trellis should be in good condition. It is important to build a history of harvest berry weights. The biggest danger is to thin too much because of lack of data. The damage factor in fruit thinning is also an unknown that only experience can determine. (Damage factor is the amount of fruit that is damaged and will later dry up but looks OK right after thinning.) The variables are variety, thinning equipment and timing. The manufacturer’s recommendations will help, and money spent on a consultant is money well spent.

A resident of the Santa Cruz Mountains, Laurie Daniel has been a journalist for more than 25 years. She has been writing about wine for publications for nearly 15 years and has been a Wines & Vines contributor since 2006.


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