Temporary Storage Via Bagging
Wednesday, December 1, 2010
filed under: Harvest/Storage
Where do you look for temporary, flexible storage when bins are not available, the elevator is full or you don’t want to dump the grain on the ground?
An alternative to consider is bag storage. The machinery and bagging systems have been around for many years, but more recently the option became a plausible choice for growers willing to make the investment.
Mike Rogers, partner-owner of Rogers Brothers Grain Storage in central South Dakota, has been utilizing a system for three years with much success. The system he uses was developed by Oakley Bagging out of Redfield, S.D. Rogers is part of the business that operates receiving stations for oil and confection sunflower for Red River Commodities, based in Fargo, N.D., and corn for the Glacial Lakes Energy, LLC ethanol production facility based in Watertown, S.D.
Another choice on the market is the Grain Bag Storage System, marketed by equipment dealers across the country. Partners Steve Hood of Missouri and Terry Twiestmeyer of Nebraska started developing the system in 2006. The equipment is built by Loftness, a Minnesota company.
Kent Albers, who farms with his sons, Chris and Josh, recently purchased the Grain Bag Storage System equipment and has utilized it to store oil sunflower, wheat and corn on their farm near Center, N.D.
How the System Works
When bins are full or not an option, the bagging system can come in handy to store crops for a short time, through the winter or even longer in some cases. A bag is simply a long polyethylene (plastic polymer) sleeve that comes in different sizes and grades of thickness, depending on the need. The bag that Rogers uses to store sunflower is 500 ft. long by 12 ft. in diameter. A bag this size can store up to 800,000 lbs. of sunflower. On the Albers farm, they use a bag 250 ft. long by 10 ft. around that can hold an average of 425,000 lbs of sunflower.
Bag storage capacity can vary, depending on need. The operator has the option to fill the bag to any capacity, cut the bag, seal it and then start a new bag. Note that the specific storage bags and capacity may vary depending on the bagging system being used.
Seed are transferred into the bag with a specially designed bag-filling machine. The loading capacity of the filling machine can vary, depending on the grain type and loading option used. Rogers’ crew can load 800,000 lbs. of sunflower into a bag using three grain carts in about seven hours. Albers said he prefers to use grain carts, as opposed to the combine or semi, because of the speed factor. They’ve found that grain carts work best because the bagging machine will take it in as fast as the carts unload.
The grain bag is emptied by a machine that rolls the bag up as it augers the seed out. Rogers says they can unload about 50,000 lbs. of sunflower into a semi-trailer in 15 minutes. Unloading an 800,000-lb. bag of sunflower would take roughly 10 hours or at a rate of 10,000 bushels per hour in the case of other grains.
There are several advantages the bag system offers over outdoor or bin storage. One advantage is portability. The crop storage bag can be put in the field where harvesting is taking place or anywhere on the farm. The harvest will not be delayed waiting for storage to become available on the farm or elsewhere, when on-site bins or off-site elevators are full.
Albers says this is the greatest benefit they’ve found so far. “We fill the bags right in the field, and it speeds up the harvest process,” he explains. “There’s no sitting around waiting for trucks to transport the seed to the bin site.”
Because storage is unlimited, the bag system gives the producer control and time to market the crop. Crops can be freighted after harvest, allowing the grower to wait for the best shipping rates.
Monitoring Moisture Levels
As with any contained storage system, the grower has to be aware of the condition of the crop going in — particularly concerning moisture levels. The bags are ideal as a dry grain storage system.
Ken Hellevang, North Dakota State University professor and extension agricultural engineer, says from his experience, the grain bag is a wonderful temporary storage system; but growers must be aware of the moisture levels of the seed. He would recommend, as with any storage structure, that moisture levels be at 10% or lower.
Rogers says it’s crucial to have the moisture level to a certain point before storage. What has worked for their operation concerning “wet” seed is to utilize the drying system in their bins before loading the seeds into the bag.
Albers says they have been fortunate with this year’s crop coming off the field at right around 10% moisture, allowing for it to be directly transported into the bags. He says if the issue ever arose with moistures higher than that, their alternate plan is to transport the seed to the aeration system at their bin site.
Timing of removing the seed is also important. Rogers recommends seeds that were on the wetter side going in at harvest time come out sometime between the first of April and the first of May to avoid issues such as an increase in seed temperature as the outside air temperatures rise in the spring.
Hellevang agrees, noting that grain stored over the winter months — particularly in the cold climate of the Northern Plains — will store nicely at the temperature of the outside air. But when temperatures begin to heat up in the spring and summer, climate will also change inside the bag.
Rogers says he is able to monitor the crop inside the bags with specially designed “windows” that can be inserted along any point. The monitoring windows can be installed literally in a minute. The sides of the window pull a piece of the bag inside and seal it. Within the opening, the producer can insert a probe up to 6 ft. long to monitor temperature levels or to take samples for further testing.
Hellevang stresses the importance of monitoring the grain, just as with any storage system. While moisture is an obvious issue, he adds insect infestation monitoring as another key concern. Based on research he has consulted, growers should be cautious about putting too much confidence in creating a controlled environment. In research conducted in Australia, data show that the level of carbon dioxide needed to completely prevent spoilage and hinder insect activity for storage over a long period of time cannot be achieved. If the grain is dry, it will stay dormant; and cold temperatures will keep insects, if present inside the bag, at bay. But the keys are dry seed and cool temperatures. If those two factors are compromised, the grower needs to monitor the seed inside the bag very closely to minimize loss.
Awareness of Common Issues
The unique, specialized design of the system allows for storage flexibility — whether in the field where harvesting is taking place or at a grain storage site— as long as the bags are placed on clean ground with good drainage and free of sharp objects.
Rogers says the system is not high maintenance, but it is important to have a high awareness of maintenance. In the right environment, the bag is the ideal storage alternative.
Filled bags for Rogers Brothers Grain Storage are on blackened ground located on a hill with no trees surrounding. This is key for keeping wildlife such as deer off the bags. Pest control is also crucial. Once in a while, if a mouse does manage to create a hole in a bag, moisture can flow in. Certain crops such as confection sunflower tend to soak up that water, so Rogers reiterates how important it is to be diligent about pest control.
One drawback to the system is that the bags are not reusable. But the option to recycle is available with some systems. An empty bag can weigh nearly 400 lbs., making it difficult to dispose. In response, the Grain Bag Storage System developers offer the Grain Bag Polywinder machine, which can be used to quickly roll up emptied grain bags. The process is accomplished by attaching the end of a grain bag to the wind-up shaft. The bag is then rolled up by a hydraulic motor that turns while the empty bag rolled around the 2x2” shaft. The bag is rolled up and tied into bales that can be sent to a recycling facility or simply for ease of storage or disposal if that is not available in the growers’ area.
There is a capital cost in buying the bagging equipment. Some farmers rent the equipment instead. Hood says they built the system to be complete to meet all the producers’ needs which includes the grain bagger, a truck unloading attachment, the bag unloader and a bag winder. Depending on the bagging system, there are different pieces of equipment to meet the needs for a specific operation.
Rogers Brothers Grain Storage owns a bagger and unloader produced by Oakley Bagging. Each 500 ft. by 12 ft. bag used to store sunflower runs about $1,350-$1,400. Rogers figures that a producer hiring out for the equipment would spend approximately $4,700-$5,500 for an 800,000-lb. capacity bag for sunflower.
Albers says he and his sons looked into all the inputs for buying their own equipment and figured that even with the significant cost of the bagging and unloading equipment, the investment would easily pay for itself within a relatively short period of time. The bags, which they have recently purchased from Richardton Farm Equipment in Richardton, N.D., run approximately 20 cents/cwt. This cost does not include the investment of the equipment for loading and unloading the bags.
Hellevang believes the bags are a wonderful storage tool and offer a lot of flexibility for growers to market their crop at opportune times. But the key is for the grower to understand the system’s limitations in order to get the most out of it. — Sonia Mullally