By
René Featherstone
Western Correspondent
Asparagus growers
in Washington have long wanted an asparagus harvester that's mechanically
selective of the spears it cuts, and soon they may be able to buy
one. A machine engineered for selective harvest began work this season
in a field of Eltopia, Wash., grower Chris Foster, who's cooperating
with the Washington State University (WSU) project that brought the
machine and its inventor to the Columbia Basin.
The sharp clacks of eight pneumatic knives syncopate the machine's
motion driven by diesel engine. Trent Ball, research assistant from
WSU-Pullman, is steering above the growing beds on the platform measuring
56 inches in height.
The inventor, Bill Lund of Lake Oswego, Ore., walks backward ahead
of his machine to observe the performance closely.
At the end of the row, everyone's pleased when only three damaged
spears are counted on the back platform where the spears are sorted
into lugs as they come across the belt. Equally important is what
remains in the wake of the machine: Lots of small spears stand up
in the row to grow into marketable gourmet vegetables in the next
few days.
Ball's boss Ray Folwell, professor in the WSU Department of Agricultural
and Resource Economics, said that an efficient mechanical harvester
is highly timely in view of the troubling production decline in the
state, from 32,000 asparagus acres 15 years ago down to 16,000 acres
today. Folwell said he agrees with growers who blame cheaply imported
asparagus for the decline – high labor costs in particular make
it difficult for Washington producers to compete.
"Maintaining acreage is a matter of industry survival,"
Folwell said.
The U.S. Congress perceived that in 2001 when it allotted special
appropriations for the USDA to pay for asparagus industry improvements
that, Folwell said, include selectively harvesting machinery.
"Selectively" is the key word. Quite a number of prototype
harvesters have been tried in the past, when Battelle Northwest, Richland,
Folwell's department undertook a mechanical harvesting study back
in 1995.
"We actually still have two non-selective harvesters," Folwell
said.
Ball said that non-selective harvesting cuts deeply into yield potential.
"From the header on back, it's the same machine I built back
in 1984," Lund said. "Three years ago I took the machine
back out of the shed."
The new header has a vertical laser beam for each knife, plus a horizontal
beam across the whole row. Both beams need to be triggered for the
knife to cut. Fingered rubber rollers deposit the cut spears onto
the conveyor belt. Certainly it's more photogenic than bent-back workers
in the dusty field.
Ball had evaluated Lund's machine for a short time last year, and
for this season he designed a protocol for a study in how the machine
compares to manual labor.
He'll count every single spear in double-row plots measuring 50 feet,
before the machine harvests and then again afterwards. Ball said he'll
use a palm pilot computer for that spreadsheet exercise.
What complicates the data evaluation is the fact that even with manual
harvesting, a considerable amount of asparagus ends up as waste, by
last year's study amounting to 1.5 tons per acre, Ball said.
"It's important that the comparison is free of bias," Ball
said. "Also, we want to be sure that the workers in the field
are comfortable with our presence, that they know we're not grading
them. Last year the workers were actually quite curious about the
machine."
Lund's harvester moves along at 2.5 miles per hour, cutting spears
on 52 acres in a 16-hour day. Estimated cost for a commercial three-row
model built on demand by Geiger Manufacturing, Stockton, Calif. is
between $60,000 and $70,000, Lund said.
Ball said he isn’t surprised that the harvester is seeing grower
skepticism.
"So many asparagus harvesting machines had already been tried,
yet none of them worked good enough," Ball said. "But after
last year's trial of this machine, the growers are more excited about
it."
At his field, Chris Foster reined in his enthusiasm.
"I reserve judgment until these guys have worked out all the
kinks," he said.
Folwell said he thinks that Lund's invention could fix some industry
woes quickly. Early in his career at WSU, in the late 1960s, he "worked
the economics" of what turned out to be a very rapid transition
from manual to mechanical harvesting in the grape industry, Folwell
said.
"Within 10 years the vast majority of the state's vineyards were
harvesting with machines," he said.
He pointed out, however, that the asparagus harvester will have to
be adapted to some of the various cultural practices, or vice versa.
"It's designed for flat (growing) beds and not for fields that
have hilled beds," Folwell said.
In addition to the harvester, labor saving fresh-pack machinery is
arriving that WSU will evaluate in follow-up testing this season as
well, Folwell said.
"The industry purchased three electronic graders and sorters,
two from New Zealand and one from Germany," he said.
Assuming that the new technology in field and shed is indeed workable,
marketing momentum could swell quickly because asparagus retains its
shining image as a top-class vegetable, Folwell said.
"The health benefits of asparagus are universally recognized,”
he said. “You sure see a lot of pictures where asparagus is
used to spruce up the image of a commodity. Just last night I saw
an ad on TV promoting eggs, and guess what was on the omelette they
were showing – cut tips of asparagus. I can remember when the
(Washington) Apple Commission used asparagus the same way on posters.
The marketing potential is definitely a good one, people have accepted
that asparagus is not a cheap vegetable."
