Should the
California Avocado Industry Consider “Snap” Harvesting?
Reuben Hofshi
Del Rey Avocado
Company
Fallbrook, California
Increasing competition from abroad requires a serious look
at all aspects of the California avocado farming enterprise. Offshore growers
spend as little as one cent per lb to harvest their avocados, while the average
California harvesting cost is greater than 10 cents per lb and rising. The
number of workers available to harvest the California avocados is shrinking.
Additionally, inexperienced newcomers are replacing the aging guard of
experienced pickers. This article will discuss how “snap” harvesting of
avocados can help improve ripe fruit quality and reduce harvesting costs,
therefore helping California growers remain competitive (Figure 1).
Fruit quality issues
“Snap” harvesting is
not a new concept and has already been adopted by other producing countries
(Figure 1). The Israeli avocado
industry, which exports most of its avocado production to Europe, has been
marketing several varieties of “snapped” avocados successfully for many
years. Other countries as well are
switching to “snap” harvesting. Visits
to the Asian market over the last 2 years reveal “snapped” ‘Hass’ from
Australia (Figure 2). Avocado
growers in Spain are also “snap” harvesting.
The driving force behind the
Spanish effort is to improve quality by “snap” harvesting their late season
‘Hass’ targeted for the French Market. Various studies conducted in Spain
demonstrated that late season Spanish ‘Hass’ avocados have high levels of stem
end rots, which could be significantly reduced by “snap” harvesting. A recent e-mail (April 2002) from Dr.
José María Farré, a researcher in Malaga Spain, summarizes the situation in
Spain:
“Since
January (2002) we have been marketing snapped and clipped fruit (from different
growers) without any problem. After further studies this year it does not
appear that dew markedly increases stem end rot under our conditions. Spanish
workers do not like to pick on wet trees anyway so I think that the
snapped-clipped discussion is over. Practically all our postharvest studies
this season has been done with snapped fruit.”
The California avocado industry recognizes that fruit
quality plays an increasingly important role in the competitive avocado
marketplace and therefore requires critical attention. Growers and marketers
have always associated “snapped” fruit with the inferior quality of stem-out
fruit resulting from over maturity and stress and windfalls. This is an
unfounded perception resulting from years of habitual clip harvesting of
avocados and lack of knowledge.
In fact, several researchers have demonstrated that
“snapped” ‘Hass’ fruit quality is comparable to that of “clipped” fruit. Dr. M.
L. Arpaia conducted a 2-year study, funded by CAC, with fruit from 3 groves in
Ventura County harvested every 6 weeks, from January through August. She found that overall the “snapped” fruit
ripened slightly faster and had slightly greater weight loss as compared to the
“clipped” fruit. More importantly she
noted that late season, beginning in June,
“clipped” ‘Hass’ had a significantly higher incidence of stem end rot as
compared to the “snapped” fruit, similar to the Spanish observations. She was able to demonstrate working with
Dennis Margosan and Dr. Joe Smilanick of USDA-ARS these researchers were that
the type and infection level of pathogens causing stem end rot in the “clipped”
fruit were more severe than with the “snapped” fruit. In short, the collaborative research by Arpaia, Margosan and
Smilanick found no evidence to indicate that ‘Hass’ avocados should not be
“snapped” harvested under the less humid conditions in California. It is likely
that of California that ‘Hass’ avocado can be successfully “snapped” harvest. Similar research in New Zealand by Dr. Allan
Woolf and Anne White of HortResearch, concluded that when environmental
conditions were “dry” that “snapped” harvested ‘Hass’ were of higher quality
than their “clipped” counterparts primarily due to a reduced incidence in
decay.
An interesting side outcome of the California research was
the demonstration that the number of decayed fruit increased immediately after
a rain regardless of picking method, although in this case the percentage of
decayed fruit was greater in the “snapped” fruit. The lesson learned is that avocados should not be harvested by either method during or immediately
after rain and before the trees have adequate time to dry out. The effect of
rain on incidence of rots is corroborated by the research conducted by Woolf
and White in New Zealand.
If you are interested in learning more about California
“snap” experimental results, go to the links at the end of this article.
Picking method comparison
A comparison between
the two picking methods illustrates that “snap” harvesting could result in
considerable labor savings. The number of moves required to harvest
a single avocado and place it in a picking bag is used here as a means to
calculate the rate of harvest by a picker. Two complementary methods are
commonly employed depending on tree height and if a picking pole is
needed. One technique, termed “3+
moves”, is used to clip the fruit that is reachable by hand. The picker holds
the avocado in one hand clips the stem with the clippers held in the other hand
and places the fruit in the picking bag. Often the picker clips the stem at a
short distance away from the stem-end and re-clips it a second time before
placing the fruit in the bag. The same method is used when placing a ladder
against the tree and picking what is reachable by hand.
The second technique, termed “4 moves”, is employed when
using a picking pole. The clippers at the tip of the pole first clip the fruit;
the fruit is brought out of the pole bag, re-clipped and placed in the picking
bag. The majority of California pickers
practices the “3+ moves” and the “4 moves” methods described above. There are
some experienced pickers who manage to clip the avocado and place it in the
picking bag with one hand in one sweeping move. However, there is a tendency to
clip a portion of the skin near the stem-end with this method, which can result
in fruit injury.
To illustrate the potential for labor savings using the
“snap” harvesting method, a comparison of the number of moves required to
commercially strip harvest a 15-20 ft tree with 100 lbs of fruit averaging 7
oz, which is the total yield of 227 fruit, is presented. The fruit distribution
on the tree is such that 40 lbs are harvested from the ground by hand; 20 lbs
are harvested by hand off a ladder; and the remaining 40 lbs are picked with
the aid of a picking pole either from the ground or off the ladder. Therefore
60 lbs or 136 fruit are picked by hand, and the remaining 40 lbs or 91 fruit
are picked with the aid of a picking pole. The picker who clips the fruit with
the “3+ moves” method requires 409 moves to pick the 136 avocados harvestable
by hand. The remaining 91 fruit are picked by the “4 moves” method and require
an additional 364 moves. The total moves required to harvest 100 lbs in the “clip”
method is 773.
The same fruit picked by “snap” harvest require a maximum of
1 move (snap and place in the picking bag in one move) to harvest the fruit
reachable by hand from the ground or the ladder (the word maximum is used because often both hands are “snapping”
2 individual fruit simultaneously and thus reducing the number of moves even
more). Therefore the 136 fruit reachable by hand require 136 moves. The
remaining 91 fruit to be harvested with a picking pole require 3 moves each,
(The stem is snapped while the fruit is being removed from the pole bag and
placed in the picking bag) for an additional 273 moves. A total of 409 moves
are required to “snap” harvest the same number and distribution of avocados.
This equates to 47% fewer moves than in clipping.
Cost analysis comparison
In Israel where harvesting is done from cherry pickers,
increased productivity/cost savings by “snap” harvesting is reported to be
approximately 50%. The current average
picking cost in California using the clip method is about 10-14 cents per lb,
with early size picking costs ranging much higher. Therefore even a 30%
reduction in the rate associated with picking becomes very meaningful. For
example, in a 385 million pound ‘Hass’ crop year the industry’s cost to harvest
the crop at an average rate of 10-14 cents per pound, will total $38.5 - $54
million. With a likely 30% savings, growers could potentially save $11.5 -
$16.2 million if “snap” harvesting is adopted. In other words, a grower with
10,000 lbs per acre currently pays $1,000 – $1400 per acre to strip pick his
trees. “Snap” harvest could potentially reduce the cost to $700 - $980 per
acre. Obviously not all trees are 15 to 20 ft tall, and the numbers presented
above are only an illustration of potential savings and are by no means
absolute. Picker experience, terrain, fruit load, within tree fruit
distribution, tree height and overall accessibility will all influence real
savings.
Manpower
The availability of farm labor, in general, and experienced
avocado pickers in particular, is becoming scarcer each year. Avocado
harvesting, especially size picking, is an art perfected over years of
experience. Even a relatively inexperienced “snap” picker can outperform his
“clipping” counterpart by significant margins. A given picker will potentially
be 30% more productive if he “snaps” the fruit instead of “clipping” it. If the
“clip” workforce harvests, through the season, an average of 1,500 lbs of
‘Hass’ avocados per day per picker, a 385 million lbs crop will require
approximately 257,000 man-days to harvest. “Snap” picking can reduce the demand
for labor through higher productivity of the individual picker, i.e. one picker
harvests more avocados per day, and thus the crop is picked with a smaller
number of pickers. The reduction in
man-days demand will be proportional to the increased efficiency of the pickers
“snapping” rather than “clipping” the avocados. Thus a 30% increase in picking
efficiency will translate to a potential saving to the industry of 77,100
man-days.
Worker safety
Clippers are sharp and cumbersome and pickers on ladders or
with picking poles need to be mindful of the clippers strung on their finger
especially in case of an emergency or a fall. The industry needs to be aware of
newly contemplated OSHA rules which may limit or disallow the use of clippers
altogether, because of the high incidence of carpal tunnel syndrome caused by
repetitive motion of clipping.
Workman compensation
considerations
The availability of sufficient pickers during the entire
season and peak demand periods, the basic per pound or per hour pay, the profit
margin of the farm labor contractor and the overhead associated with equipment,
housing, transportation, taxes and workman compensation, all contribute to the
cost of harvest. The increase in the minimum wage rate at the beginning of 2002
explains the recent increase in the basic cost per pound. Additionally, in the
last year, the workman compensation rate for orchard work increased to 20.5%.
Discounts for existing policyholders associated with credits plus experience
modification bring the rate, in real terms, to an average of 15% of gross
payroll.
On February 15, 2002 Governor Davis signed into law AB 749.
This law will increase benefits for temporarily and permanently injured workers
from $490 to $602 weekly starting on January 1, 2003. Benefits will continue to
rise until 2005, when the maximum will reach $840 a week. Starting in 2006, benefits will be adjusted annually based on
increases in the state’s average weekly wage. Workers with partial but
permanent injuries will see an increase ranging from $130 to $270 a week. The
current benefits range from $70 to $230 a week. In addition, the current
maximum death benefit will double to $320,000. Some business interests estimate
the cost increase to the state's employers at $3.5 billion. These increases will particularly impact
farmers and will significantly
influence the harvesting costs of avocados in California and may place
harvesting cost as equal or even ahead of the cost of water!
In conclusion, the
California avocado industry will be well served if it seriously considers
adopting “snap” harvesting as the
method of choice for harvesting ‘Hass’ avocados throughout the season. Although
studies are still needed to demonstrate the acceptability of “snapped” avocados
in the trade and marketplace, the research we funded makes a good case in favor
of removing the stem and a good starting point for discussion with the
buyers. The potential cost savings that
“snapped” avocados represent to our industry is substantial. Our goal must be
to improve the quality of our avocados, as well as to reduce our costs. In this pursuit, hiding behind traditional
customs and perceptions is a habit we cannot afford.
Links to papers discussing fruit quality of “snapped” avocado
Arpaia, M.L. and
R. Hofshi. 1998. The feasibility of
“snap” harvesting of ‘Hass’ avocados.
Subtropical Fruit News http://www.avocadosource.com/avo-frames.asp?Lang=en&URL=http://www.avocadosource.com/papers/Arpaia%20and%20Hofshi%20'snap'%20harvesting.htm
Margosan, D.A.,
J. L. Smilanick, M.L. Arpaia and J. R. Sievert. 1999. Fungi isolated from
avocados with stem-end rot after “snap” or “clip” harvest. In: M.L. Arpaia and R. Hofshi (eds.),
Proceedings of Avocado Brainstorming ’99:150-151.
http://avocado.org/static/growerres/proceedings/p8_margosan.php
Margosan, D.A.
and J. L. Smilanick. 2000. Fungi isolated after harvest from decayed
California avocado fruit. California
Avocado Research Symposium, October 14, 2000:101-103.
Smilanick, J.L.
and D.A. Margosan. 2001. Management of postharvest decay of avocado
fruit. California Avocado Research Symposium, October 20, 2001:115-119. http://avocado.org/static/growerres/symposium-2001/smilan.pdf
Woolf, A., A.
White, J. Sievert and M.L. Arpaia.
1999. Summary of New Zealand and
Californian experience with “snap” picking. In: M.L. Arpaia and R. Hofshi
(eds.), Proceedings of Avocado Brainstorming ’99:161. http://avocado.org/static/growerres/proceedings/p8_woolf.php
These articles could be also found through links available
at Reuben Hofshi’s web page www.avocadosource.com.
