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October 1997, Volume 3, Number 4

Grape Mechanization

Much of American history is the story of
producing more food and fiber with fewer people. As more farm workers
appear to be unauthorized workers and farmers ask for legal workers,
some ask why the US does not encourage mechanization instead of
importing farm workers.

There has been extensive mechanization of
wine grapes in the past decade, but little mechanization of raisin

The US is the world's third-largest
producer of grapes, after Italy and France. US grapes in 1996 were
worth $2.2 billion. About 90 percent of US grapes are produced in
California, and three percent each in New York and Washington. Most
US grapes by tonnage are processed: 85 percent, including 64 percent
that are turned into wine, 28 percent into raisins and eight percent
into grape juice.

About 15 percent of US grapes are consumed
fresh, but they generate the highest grower prices: an average $718
per ton or $0.36 per pound for fresh grapes, $410 per ton for wine
grapes and $231 per ton for raisin grapes.

Americans consumed a record 7.5 pounds of
fresh grapes per person in 1994/95, and another nine pounds of
raisins per person.

California had a record 744,000 acres of
grapes in 1996, including 378,000 acres of wine grapes, 277,000 acres
of raisin grapes and 88,000 acres of table grapes. California grape
products were worth $2.1 billion at the farm level in

Wine Grapes. Between 1975 and 1995,
the percentage of wine grapes harvested by machine increased from
less than 10 percent to about 70 percent, with the most mechanical
harvesting in the San Joaquin Valley. Four hand harvesters can pick
about one acre of grapes per day; a mechanical harverster, which uses
a crew of five to harvest around the clock, can harvest 10 to 20
acres per day.

Wine grape harvesters cost $100,000 to
$200,000 each, but they can harvest wine grapes for $15 to $25 per
ton, compared to $35 to $50 per ton for hand harvesting. Gallo,
California's largest grape grower with 10,000 acres in the San
Joaquin Valley, has 17 mechanical grape harvesters. California
expects about 3.5 million tons of wine grapes in 1997.

Most wine grape harvesters straddle the
row and use shaking rods to dislodge the grapes, which fall onto a
conveyor belt and are taken to an adjoining gondola. Leaves and
debris are blown away from the grapes by a fan and by hand. Wine
grape growers have recently turned their attention to mechanical
pruning, including using flame throwers to get rid of excess

An estimated 70,000 acres of new wine
grapes were planted in 1995-96, including 20,000 additional acres in
the Lodi area, 10,000 in the Salinas area, and 5,000 in Santa Maria.
In 1996, California wineries sold wines worth $5.2 billion.

The average American consumes 1.6 gallons
of wine annually, and 22.4 gallons of beer. California's vineyards
continue to expand, to 355,000 acres in 1996. About 16 percent of US
adults consume 88 percent of the wine drunk in the US. In June 1997,
it was announced that 42 California wineries had received $1.9
million from USDA's Market Access Program, a taxpayer-supported
program that covers 50 percent of the cost of advertising US wines
abroad. The US exported wine worth $327 million in 1996.

An analysis indicated that the cost of the
grapes in a $20 retail bottle of Napa chardonnay is about $2.25,
while the distributor and retailer mark up is $10. On a $7 retail
chardonnay, the grapes cost $1, and the distributor and retailer mark
up is $3.50.

Table Grapes. California is
expected to produce a record 80 million 21-pound boxes of table
grapes in 1997, up from 64 million boxes worth $941 million, about
$15 per box or $0.70 per pound in 1996, and 72 million boxes worth
$838 in 1995. Table grape yields average 700 to 750 boxes per acre.
About 25 percent of US table grapes are exported, including 37,000
metric tons to Hong Kong, 15,000 metric tons to Taiwan and 12,000
metric tons to the Philippines.

Most table grapes are field packed, which
means that workers cut bunches of grapes, and take them to the end of
each row, where they are packed into boxes, and taken to cold storage
locations. Many table grape operations are major employers of farm
workers: Zaninovich table grape farm in California's San Joaquin
Valley sold about five million 25-pound boxes of grapes annually at
an average price of $10-$15 per box in the mid-1990s, and hired 1,000
farm workers to help generate $50 million in annual grape

Table grape harvesters are typically paid
$5 to $6 per hour, plus about $0.30 per box of grapes picked and

Raisin Grapes. In a June 1997
report, Mason describe the Dried-on-the-Vine (DOV) method of
harvesting raisin grapes, which can reduce the hours of labor needed
by 60 to 85 percent. The 5,500 raisin growers in the Fresno area hire
40,000 to 50,000 workers each year to cut bunches of grapes on
200,000 acres of vineyards and lay them on paper trays to dry in the
sun; up to 50 percent of the harvest workers are not authorized to be
in the US.

Workers were paid $0.15 to $0.17 per
25-pound tray in 1991, and averaged $6.25 hourly. In 1991, virtually
all raisin harvesters were born in Mexico and one-third admitted to
being unauthorized.

The DOV method of harvesting involves
cutting the vines holding the grapes but letting the grapes turn into
raisins while suspended on the vine rather than on paper trays. The
dried bunches of raisins are then removed mechanically, saving up to
three-fourths of the peak harvest labor. In one experiment, the
amount of labor per acre was similar in the two systems, but with
DOV, labor was hired throughout the year rather than peaking in

The report notes that it may be difficult
to encourage labor-saving changes in the grape industry because the
average grower is 63, has less than 50 acres of raisin grapes, and
DOV requires significant retrofitting, up to $2,000 per

Previous efforts to mechanize the grape
harvest involved a beater-rod system in which rotating fingers
knocked individual grapes off the vine and put them on continuous
paper trays to dry. That system also requires that the canes be cut
seven to 10 days before harvest.

Mechanization is funded in part by
growers, and their "need" for labor saving machinery depends in large
part on the cost and availability of labor. Phil Scott, owner of
Ag-Right Harvesters in Madera, believes that DOV raisin harvesting
will be slow to develop unless there is a "shortage of labor. A
farmer is pretty much content to do what he did last

Madera grower Lee Simpson has developed a
pergola trellising that shades the whole vineyard floor much of the
summer on 145 acres that has twice as many vines per acre as usual.
Labor costs are $28 per ton, compared with $228 per ton with
conventional methods, and yields are four to five tons per acre,
compared with the industry average of two tons per acre. Simpson
spent $4,500 an acre to develop his vineyard; a conventional vineyard
can be developed for $2,000 an acre.

A 1989 article in the Packer said that:
"with an abundant and reasonably priced labor force at hand...why
bother pushing for research into added mechanization." (January 28,
1989, page 46B)

Some growers try to reduce their cooling
costs and the heat stress on workers by harvesting at night. Portable
lighting systems have become cheaper and more efficient, and several
table grape growers have added night harvesting machines, although
most grapes continue to be picked during the day.

J.N. Sbranti, "Mechanical wine-grape
harvesting on the rise," Fresno Bee, September 22, 1997. John G.
Taylor, "Panelists pit high-tech vs. farmworkers," Fresno Bee,
September 18, 1997. Dennis Pollock, "Vine harvesting: A ripe idea?"
Fresno Bee, August 24, 1997. Mason, Bert, R. Keith Striegler, and
Gregory Berg. 1997. Alternatives to immigrant labor? raisin industry
tests new harvesting technology. Washington. Center for Immigration
Studies Backgrounder 2-97. June. Alvarado, Andrew J., Gary L. Riley
and Herbert O. Mason. 1990. Agricultural Workers in Central
California in 1989. California Agricultural Studies 90-8. Sacramento:
State of California Employment Development Department, Labor Market
Information Division.