Download Popularity of harvest bags heating up

© Kondinin Group
Cropping
Grain storage
This article has been reproduced with permission from Farming Ahead.
For more information about Kondinin Group phone 1800 677 761.
Further duplication of this article is not permitted.
Popularity of harvest bags heating up
Grain harvest bags are gaining global popularity as a low-cost, temporary storage system for maintaining grain condition
for many months post-harvest.
At a glance
• Grain harvest bags are low-cost
grain storage units used to store
harvested grains safely, allowing
growers to better manage and
market their crop.
• Each bag can store up to 300
tonnes of grain in an airtight
environment which also provides
protection from pests.
• Grain storage bags in Australia
might enable ripe crops to
be harvested at higher
moisture contents, increasing
harvest flexibility and
overall productivity.
G
rain harvest bags are an increasingly
popular way for growers to capture,
control and conserve the maximum value of
a crop.
The bags are low-cost membrane-based
grain storage units which allow growers to
by
accelerate the production of carbon dioxide
and depletion of oxygen. These conditions
suppress the activity of any fungi or
insects present, preserving the grain in its
original condition.
Louise Lawrence
and Len Caddick,
CSIRO ENTOMOLOGY
store grain on-farm, bypassing expensive
contract transport and enabling the rapid
harvest of a ripe crop at its maximum value.
The bags can be used to store early
harvested grains safely and to segregate grain
into small, identifiable batches, allowing
growers to better manage and market crops.
Harvest bags are an effective and
economical alternative to permanent,
expensive on-farm storage and can also
facilitate the use of contract harvesting,
especially when on-farm storage and
transport are limited.
World trends
In Argentina, where permanent storage is
in short supply, the use of grain harvest bags
has increased rapidly. During 2004, grain
bags were used to store more than 18 million
tonnes of Argentinean grain, including
wheat, maize (corn) and soybean.
The bags are also becoming popular in
other Latin American countries and in South
Africa, where they provide an economical
system for short- and long-term grain storage.
The rate of adoption on farms is a reflection
of the success of this technology in
maintaining grain quality to required
marketing specifications.
The triple-layered polyethylene bags have
largely been developed in Argentina, where
similar plastic bags have a long history of use
to store silage. Argentina has also developed
machinery for handling harvest bags.
Harvest bags have been used in Australia
for several years, but the limits of this
In the bag
Harvest bags produce an airtight
environment
and
under
favourable
conditions grain is protected against insect
pests without the use of pesticides.
Each bag is seamless and holds up to 300
tonnes of grain. After the two ends of the
bag are sealed, the moisture content and
temperature of the enclosed grain interact to
Grower reaps $30,000 saving by using harvest bags
Farm information
Using grain harvest bags instead of buying 10 new silos saved Victorian mixed
farmers, the Nicholson family, more than $30,000 during 2005.
Farmers
by
Megan Broad,
for CSIRO ENTOMOLOGY
Location
Campbell's Bridge,
Victoria
Property size
1360ha (90% arable)
Enterprises
Cropping and sheep
Annual rainfall
400–475mm
Soil type
Grey clay to light
sandy loams
Soil pH
5.6–6.8 (calcium chloride)
48
S
avings of $30,000 and the opportunity
to store grain to sell during market
peaks prompted Campbell’s Bridge,
Victorian growers, the Nicholson family, to
try grain harvest bags.
Robert Nicholson
Robert, Lorraine and
Scott Nicholson
Robert, Lorraine and Scott Nicholson, Campbell’s
Bridge, Victoria, believe they will be ahead in cost
savings with harvest bags as the bags do not
require fumigation like silos.
Robert Nicholson decided to try the grain
harvest bags during 2005 to store 750
tonnes of his noodle wheat, oats and barley
to provide more marketing flexibility.
One option to store the grain was to buy
10 new 75t silos, worth more than $80,000.
Rather than selling the grain as it was
harvested at the lowest point of the market,
Robert wanted to store the grain to generate
more profit per tonne from pre- and postharvest sales.
Instead, Robert bought a machine to fill
the grain harvest bags for $17,000 and four
75-metre long bags at a cost of $15.50/m
(about $4/t wheat stored). At the time of
publishing he was unsure whether he was
FA R M I N G A H E A D
No. 171
April 2006
technology under Australian conditions have
yet to be determined.
Typically, Australian grain is harvested
drier than in Argentina, which could be
an important factor in determining the
performance of storage bag technology,
since dry grain is unlikely to have sufficient
fungal or respiratory activity to generate the
advantageous low-oxygen, high carbon
dioxide environment.
Further, although the grain might still
store well in this situation, there is a chance
that the bags might not develop an
insecticidal environment, and that moisture
movement in the bags could lead to
localised moulding.
Technology trial
Researchers from CSIRO Entomology
will study harvest bags to determine
their effectiveness in Australian conditions.
Trials will determine whether silo bag
technology offers growers significant
advantages over traditional storage methods
and whether using this technology under
Australian conditions might expose the
grower to unexpected risk.
The study will include research into the
possible loss of processing and end-user
quality, as well as the overall cost and logistics
associated with grain bag use.
The trials will track the quality of wheat
stored in grain bags in a paddock for up to
12 months.
A grain sample and profile will be taken
for each bag during filling and out-turn
going to use a contractor or buy a machine
to empty the bags, for an estimated cost
of $25,000.
Either way, Robert believes he will still be
ahead in costs savings, especially as the
bags do not require fumigation unlike silos.
Although he acknowledged the cost of
replacing the bags each year, Robert
maintained the increased market flexibility,
storage flexibility and minimal maintenance
made the option more viable to him than silos.
Filling the bags
The process of filling the bags was
straightforward and efficient.
A total of 250t of wheat, 200t of barley and
300t of oats was put into four bags.
One wheat bag held grain from two
different paddocks, which yielded different
protein levels, separated by a line drawn on
the bag to define the change of grains.
Robert maintains even if he loses 1t of
grain from the grain mixed at the separated
line, the loss will be insignificant compared
with mixing the two grains in a silo
and effectively reducing its value and
FA R M I N G A H E A D
No. 171
April 2006
Cropping
Neil McAlpine
Grain storage
During 2004, Argentinean farmers used harvest bags to store more than 18 million tonnes of wheat, maize
and soybean. If used in Australia, the bags might allow harvest of ripe crops at higher moisture contents.
and probe samples also will be taken
during storage.
Unpowered sensors in the bags will
take temperature and relative humidity
measurements to determine any risks to the
grain. Oxygen and carbon dioxide levels also
will be monitored closely to assess whether an
airtight environment is achieved.
The results will help determine whether
the bags will enable harvest at higher
moisture contents, since the ability to harvest
ripe crops wetter can increase harvest
market opportunities. The massive plastic
bags are delivered folded into a large cylinder
and are winched over the machine. One end
of the bag is sealed and the Nicholsons used
a chaser bin to auger the grain into the
bagging machine.
Bag durability
Robert’s main concern about the bags
is how they will withstand white cockatoos
as he has already found one or two holes in
the bags. He does not believe Australia’s
harsh climate will be a problem, provided the
grain is emptied within 12 months, although
he does have reservations about how it will
withstand a hailstorm.
Grain quality
Robert is keen to find out if there is any
impact on the quality of grain from the bags
as maltsters reputedly have concerns about
moulding from harvest bags and any
deterioration would reduce the system’s
appeal by reducing marketing options.
The Nicholson family also leases some
country and sees potential to use the bags
on grain harvested there, rather than
transporting it back to the main property.
flexibility, reduce weather damage and
increase overall productivity. The study,
funded by the Grains Research and
Development Corporation, will start with an
extensive survey of growers already using the
technology to assess the current performance
of the bags, highlight the advantages of their
use and document any problems encountered
with loading and out-turn and during storage.
For more information contact
Len Caddick, CSIRO Entomology,
on [email protected] or phone
(02) 6246 4214.
At a glance
• Compared with buying new
silos, adopting the harvest bag
system saved $30,000 for
Victorian mixed farmers Robert,
Lorraine and Scott Nicholson.
• Grain in the harvest bags can be
sold during price peaks rather than
during grain gluts.
• Different grains can share a
bag with only small losses from
grain mixing.
• The Nicholsons have some
concerns about potential damage
to the bags from white cockatoos
and hailstorms.
For more information contact
Robert
Nicholson
on
email
[email protected]
or
phone (03) 5359 0218.
49