Field Practices Report on 1999 Rice Straw Harvests

This page updated September 17, 2007.

Field Practices Report on 1999 Rice Straw Harvest

Submitted to California Air Resources Board Rice Fund Grant

(April 5, 2000)


By Steve Van Mouwerik
Anderson Hay and Grain Co., Inc.


During September and October 1999, Anderson Hay and Grain again teamed up with our Oregon baling supply partner, Gerald Phelan, Inc., to produce about 11,000 bales, or approximately 5,500 tons of rice straw.

This year we operated one Freeman 1592 and two Hesston 4790’s. We leased one of the Hesstons from an equipment dealer and hired the other as a fully operated unit by a third party. We had observed the operation of this third party’s Hesston baler during Oregon grass straw harvest and confirmed that the Hesston had every reason to out perform the Freemans. The Hesston, a mechanically vs. hydraulically driven baler, was faster and more reliable, while not sacrificing in bale weight.

We operated two Allen rakes, a hydraulically driven rake, pulled by our own tractors. Instead of contracting with a local stacking service to stack and retrieve the bales from the field, we used two of our own stack wagons. We contracted with an Oregon trucker that we use at other times of the year for hauling alfalfa and Oregon grass straw to handle harvest trucking from field to local tarp and barn storage sites. The trucker’s work was supplemented by a rice grower who supplied trucking prior to and immediately following his rice harvest needs, making a very good fit for all. We contracted with a Washington State firm to tarp straw stored overwinter in Biggs.

This report describes our procedures and our post harvest review and evaluation of these procedures. Our efforts this year were based on utilizing experience gained from 1998 rice straw harvest of 5,000 tons and on continued reference to Oregon straw harvesting experience and methods to develop a "best practices" approach to the California rice straw setting.

Our activities took place in the Gridley-Biggs area and in the Colusa area. The baling time period was September 23 – October 26.

Straw Harvesting: Equipment, Practices, and Ground Conditions

The basic equipment set-up for harvest was modified from last year’s due to increased performance out of the Hesston balers. Instead of a "normal" configuration of equipment of one rake, two balers, and one stack wagon, we evolved to two-three rakes, three balers, and two stack wagons. We believe that with the addition of a third Hesston (replacing the Freeman) to the lineup, we would probably see equipment mixes optimized at one rake per baler, but two-stack wagon per three baler / rake pairs. This "unit" best matches each piece of equipment's productivity to the other and represents a basic building block in allocation of equipment resources to the field, and fits what one crew and equipment leader can service and support.

Baling rice straw must occur during the day after the nighttime dew moisture has dissipated. A normal September - October day was from 10:00 a.m. - 11:00 a.m. to about 7:00 p.m. - 9:00 p.m. Depending on the presence of a breeze, clouds, humidity, this remained the typical range of operating hours, all due to moisture. These circumstances prevailed again in 1999, confirming our first year’s experience.

Once again, the uppermost limit in baled straw moisture was set at 15% in the straw baling conditions, with 13% or lower as the strike-point. Under these conditions, the Hesstons produced between 200-350 bales per day per baler (as compared to the Freeman 1592s’ performance range of between 150-200 bales last year and again this year.) Bale weights ranged from 850# to 1,050#. This larger variation (last year we ran more between 900# and 1,000#) can be attributed to learning to operate the Hesston, trying to maintain much higher rates of production (which directly affects bale weight), and to several fields that were quite light in straw yield, which makes it hard to build a dense bale.) We believe that we can obtain a 950# average weight from a Hesston and a very strong 250 bales per day average output.

The straw was baled between 8% and 14% moisture, but mostly at a 12% number. 14% is an upper threshold for straw that is compressed, containerized, and shipped to Asia. Higher moisture levels can produce an unacceptably high level of mold problems, odor problems, and processing problems.

A bale length of 8 feet (96 inches) was confirmed to be ideal. Tie layers were confirmed as unnecessary during 1998 harvest because the rice straw can be built into very solid, square-edged units that stack reliably, safely, and well.

Between 94 inches and 102 inches is where the "battle" is fought to build the best bales. The extra / less length directly affects weight achieved. However, at 102 inches a bale produces a slightly overwidth load and hence compliance issues for the trucking leg. We worked to achieve a consistent 1,000-pound bale without "cheating" by adding length beyond 96" and without slowing down too much to run extra, but smaller, strokes. Using a standard big bale twine strength was very acceptable, however we did find that running a 500# test twine on the outside ties helped keep twine around the heavier bales and during the hottest and driest part of the afternoon when it is most difficult to achieve top weight.

Last year it quickly became apparent that ground conditions were key. The baler was not the weak point in getting through fields; the stack wagon was the weak point. This remained very true. In fact, if the 1998 crop year was characterized by laid-down, or lodged, fields, the 1999 crop year was characterized by wet fields due to water having been pulled from fields much later (about two-three weeks) than normal. This raised everyone’s awareness of getting equipment in and out of fields.

To this end of managing equipment movement in and out of checks, we developed a pattern – which relies a great deal on close communication with farmers - of baling the straw as soon as it was dry, even when the ground was too wet for removing the bales with stack-wagons. This approach allowed us to keep moving balers and rakes in the best pattern from check to check to check without too much "roading" from dry check to dry check, an expensive use of time and equipment when one needs to have balers in the check consistently making bales rather than running between fields and checks. Meanwhile, stack wagons, with greater mobility, could jump as needed based on field accessibility.

The removal of the straw from the ground into bale form greatly speeded the drying rate of the ground – from four-six days to two-three days. Thereafter, the stack-wagons could retrieve the bales with fewer wet ground problems. The utilization of stack-wagons that have deep lugs rather than smoother profiles assisted greatly in avoiding getting stuck in the wetter ground. Nonetheless, the development of a front wheel assist or dual-wheel front and back axles of a 2WD stack-wagon remained an idea that everyone felt would be very helpful in expanding field access into damper conditions. This could really assist in achieving the goals and benefits described above.

Raking remained the first activity in the field for the baling operation. Our procedure begins with having the combines spread the rice straw behind them rather than leaving it in a windrow. The purpose of this is to enable the straw to dry evenly and more quickly and to avoid inevitably wet, uncured straw at the bottom of windrows. Also, in the event of especially heavy dew and rain, the spread material always drys out more quickly and evenly. This is based on our practices in Oregon and is considered well proven.

A key point we learned from 1998 harvest that we applied very strictly to 1999 harvest work was to avoid torn up ground in the checks where rice harvesters and bank-out wagons had rutted and disturbed the soil. Running rakes across this part of the checks (typically near entrances and along check sides) puts them into this disturbed ground that has variations in elevation that put soil into the working range of the rake teeth. This causes soil clods and pieces to be raked up into the straw windrow intended for baling. Capturing soil into baled straw intended for export markets is utterly unacceptable.

What we developed with our rice growers during 1999 harvest was their understanding that we could not rake the sections of a check that were disturbed and rutted. By avoiding those portions of the check and by constantly checking rake settings, we could get onto damper ground and get the straw raked up and dried for baling. The balers could get in and out of the checks to bale up the straw without getting stuck, enabling the ground to dry for the stack wagon work.

One issue for export, however, is leaving bales sitting on damp ground under this practice. Moisture wicks up into the bottom of the bale rendering it unfit for export market quality requirements. We are uncertain how much we can push the bottom of the bale problem in order to speed field drying for stack wagon access, but believe it is limited.

It is important to rake the windrow onto the stubble and not onto flattened areas from combines. Doing so speeds drying and avoids exposure to damper ground. It also maximizes clean pick up by baler teeth. We confirmed and continued this practice from 1998 to 1999.

Ideally, the rakes are set to 4" off the ground and the straw is sitting atop stubble that is 6" in heigth. This 6" height corresponds to the water line. Higher stubble than 6" hurts straw yield and hurts raking speed and effectiveness. Lower stubble puts equipment closer to the ground than it should be for purposes of avoiding soil pickup, soil exposed portions of the plant that were under water, and higher moisture straw.

This important point cannot be understated: Export market users of straw have a zero tolerance for soil content in straw and hay. Working very closely to the gound – especially disturbed, uneven, rutted ground - with pick-up equipment invariably leads to greater soil content (clods and clumps) in the baled straw. Developing and maintaining industry-wide practices that consistently and effectively keep soil out of straw will be key to California rice straw being successful in Japan.

Picking up straw that has been cut by the combines below the water level raises soil / ash content of straw and introduces much higher phyto sanitary concerns and "friction" within the export market. There is too much activity too close to soil. It is very clear that grower and baler alike benefit from working at a cutting, raking, and baling waterline stubble of about 6" that is atop relatively undisturbed ground.

There is a trade off between speed of rice harvest and amount of straw load on the field. Ideally, the harvester would cut at water level for us. Ideally for the harvester, cutting a bit higher speeds moving through the field - a critical matter during harvest when speed is essential. When they cut higher the combines can go faster, but at the expense of getting an ideal 2 tons per acre of straw (which keeps balers fed and building bales most effectively.) If the grower cuts just at the waterline, the yield is ideal for the straw and it appears the grower can readily enjoy the benefits of farming the stubble back into the ground. This leads us back to the ideal level of 6". Fields cut at this level produced an average of 2 tons per acres in straw yield in 1998 and 2.14 tons per acre yield in 1999.

Equipment operators need to watch out for alkali holes. We avoided these spots this year that we found in 1998.

The number of days after combining before straw could be baled depended on ground moisture and stubble heighth. For example, one grower’s ground was as especially firm. He had put in rotary ditches (cut ditches) toward the drainage end of the dike. This practice allows growers to use wheels not tracks under their combines and avoids tracking up the ground. It also makes the ground harder and more suitable to straw harvesting equipment. Baling equipment could run faster and more efficiently and smoothly on this ground. Two years in a row on this type of ground confirmed these observations.

Ground moisture also depends on the type of ground – whether it is heavier or lighter soil. Two types of soil on opposite ends of a drainage spectrum may characterize farm ground we encountered: silty / clay soils and more sandy soils. The heavier silt / clay soils seals in moisture making for more moisture issues in moving equipment across the ground. From our point of view the better draining, sandier soils were preferable during the earlier part of harvest season (closest to water being pulled from checks) and would be important towards the end of the season in the event of rain showers intruding earlier in the latter part of the harvest season.

Once again, tractors with dual-wheeled rear axle and four-wheel drive (4WD) performed very satisfactorily through all types of soils. Our greatest equipment mobility problems by far came with the stackwagon. Stackwagons typically utilize lightly treaded tires enabling faster, more efficient road speeds and even field speeds. . We remedied 90% of this last year by putting on lugged back tires, which cut into the wetter, slicker ground, giving adequate traction to the stackwagon. We confirmed during 1999 harvest that lugged wheels are essential to working in rice checks under the ranges of ground conditions encountered during a typically harvest.

Some part of stacking may well need to be a pull type in order to gain time in very marginal or wetter ground. This would give us performance in areas that have heavier soil or in a wetter year. Also, this would enable us to address the need to move bales off wetter checks before the bottom-side wicked up enough moisture to affect the quality critically for the export market.

One note is that new tractors are good for 30 mph vs. 18 miles mph. This may address the speed issue of the pulled stackwagon scenario and allow us to retain needed productivity levels of the stack wagon.

Access to checks: After our work in 1999, we found that check access was tolerable. We found that for the most part we can make our way in and out of checks. Most access can be improved by a small amount of dirt work by existing blades and equipment that farmers have.

Overall, the value of "lighter" with more "floatation" is better when moving in and out of rice checks.

General Logistics

In our 1998 report, we concluded:

    Most stack pads for staging stack wagon dumps were too small. This small field stack staging capacity increased pressure on squeeze / trucking crews moving field stacks to storage locations. (A common scenario was two checks capacity out of a 12-check field.) Straw staging and working area needs much improvement and will be an important thing to work out among growers and straw harvester. Trucking management is more critical due to smaller staging areas. Due to field soil conditions we didn’t stack straw blocks and load trucks in the field. Only stack wagons could go in and out of the checks and fields. Too often the stack wagon had some trouble with high centering between checks when crossing the cuts. This is very important because of the number of trips that a stack wagon must make to retrieve blocks to staging pad out of field by best corner for truck access and squeeze operating for loading room.

In 1999, we noted:

    Even though stack pads (which have really been sized over the years to equipment staging needs for rice harvest) were too small for our ideal, we learned to use roadsides and corners of fields that were dry and had access for staging stacked straw for removal by truck to storage. We also learned to schedule stacking/staging and loading / trucking with each other in accordance with available room. This accommodation of tighter stacking room went reasonably well.

    We again saw the need for widening culvert covered approached in order to accommodate longer trucks than are common in just rice harvest activities. This would have to be developed on a farmer-by-farmer, location-by-location basis.

    It is clear that moving straw to these smaller corners’ staging areas increases the trip time for stack wagons and decreases the productivity of the stack wagon due to longer distances per trip. We saw a 40-50% lower productivity in stack wagons in rice straw vs. in Oregon grass straw, due to significantly longer roundtrips between field and field-side stack. Clearly, we foresee a higher stack wagon need (and higher associated cost) than in Oregon, but also foresee the need to develop additional stack yards where possible that are located strategically in order reduce travel within fields and among checks.

    Where ever growers had landing strips is ideal staging off of field. We made full use of these when available. They are very welcome working and staging areas. They contribute to the longer trips by stack wagons than if we could stack in the field or check, but do give us the needed room to stage larger quantities of straw without having to immediately schedule the take-away trucking.

Stack wagons need to hump over several checks to get to the stack area. In 1998 we noted that the humps needed to be cut flatter to expedite better movement. In 1999, several growers did this for us and it was very helpful.

Truck access and average stack wagon trip distances will affect harvest costs and overall smoothness of movement from country to storage destination. We know we will need 50% more stack wagons than in Oregon due to stack wagons being required to run longer distances to move straw out of field / check, not just to nearest point of building a 7 or 8-pak of units for squeeze loading in the field.

100,000 Ton Harvest Equipment Scenario

This scenario is offered as a second year outline (revised after 1999 harvest) of necessary equipment to accomplish a 100,000-ton harvest. It is based on the assumption that 25% of ground to be covered is "wetter" than dryer, as we had in 1999 harvest. Further, we are changing our assumption of a harvest window from 60 days in last year’s report to ONLY 40. This is due to the fact that we have now had two years in a row of seasons that were running more at 40 days of activity possible rather than 60. We see the core of this window between September 10 and October 20.

21 Big Balers - Based on Hesston balers.

14-21 Rakes - Based on Allen rakes.

25-41 Tractors

14 Sackers - Several stack-wagons would be 4WD or dualed for more floatation.

Balers

No modification from Oregon grass straw or from dealer.

Baler Tractor

100% wheeled power units, relying on 4WD and floatation, with our current thinking that were tracked equipment needed, conditions would be getting pretty wet and expensive with quality issues to compound these two considerations.

Rake

Outside tire of rake would be a floatation design.

Rake Tractor

Stay with 4WD.



Progress Report Executive Summaries

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