Industrial Short Rotation Intensive Cultural Operations

Thomas H. Morgan, Jr., Scott Paper Company, Mobile, AL USA

INTRODUCTION

This paper presents a brief history of Scott Paper Company in Mobile, Alabama in general and an outline of our work with Short Rotation Intensive Hardwood Culture in particular. The Mobile plant began as Hollingsworth and Whitney in the 1930s and was purchases by Scott paper in the 1950s. Scott Paper Company manufactures personal care products and printing media at the Mobile site. Two hundred thousand ha of timberland in the southeastern United States supply 40 percent of the fiber needs for this plant. Presently all pulpwood is chipped at the Mobile site for consumption in our pulp mill. Final transportation of pulpwood to our Mobile site is done primarily by water with 90 percent all solid wood delivered by company-owned river boats and barges and the balance trucked into the gate. Our co- generation facility produces 100 MW of electricity (mill's demand) on site. In producing this electricity, the co-generation plant uses 110 t per hour of wood waste, among other energy sources. Four in-woods biomass harvesting crews produce 225,000 t of this wood waste from non-merchantable biomass in stands of timber scheduled for harvest. The balance comes from our chip plants, and is also purchased from other wood-using industries in this area.

Fiber Resource Strategy and Operations

As stated earlier, fee land produces approximately 40 percent of our fiber needs and constitute our most cost-efficient source. This land base is comprised of about 60 percent pine plantations managed on even-aged 25 to 30 year rotations primarily on pine uplands and flat sites. Lobolly and slash pine dominate formerly planted species. The remaining acreage of our fee land base is managed for hardwood production. These stands are predominately bottomland hardwood sites that are regenerated naturally by "silvicultural" clearcuts. A relatively small amount of our land base is dedicated to short rotation intensive culture hardwood plantations. These stands are predominately sycamore plantation intensive cultured on 5 year rotations. SRIC plantations are placed on upland pine sites in order to provide a source for winter season hardwood fiber.

Scott employee timber buyers negotiate and purchase about 60 percent of the timber coming off land not owned by Scott Paper Company both by dealing directly with other landowners or purchasing timber from other wood producers directly at out yard gates.

Uniquely, Scott Paper Company's Southeastern Timberland is dedicated to the concept of company harvesting crews. Scott Paper Company operates 40 company logging and 4 energy harvesting crews throughout Mississippi and Alabama USA. We are now probably the largest logging operation in this country.

History of Short Rotation Intensive Culture Plantations

Prior to 1975, a small amount of wood waste was used in our boilers, primarily mill shavings and bark. We would also have sawdust brought in from cabinet shops, a clock factory, etc. In 1975, Dick Snider, our mill manager, turned procurement of biomass fuel over to the woods division in order to increase the volume and quality of fuel being used. This was when fuel prices had rocketed up and wood waste was a much cheaper alternative fuel. We visited a whole tree chipping crew that supported the fiber board plant of Masonite Corporation and decided to give it a try. We purchased a 25 cm Morbark<2> chipper, a Melroe Bobcat which had been converted into a feller-buncher, and 3 chip vans and started our first energy harvesting crew. We started out harvesting after the logging crew had removed merchantable timber, but quickly found out that it was more economical to pre-harvest stands for biomass. In 1984, we expanded the utilities complex and started up 5 more energy crews based on the experiences of our start-up crew.

Also during the period of the mid- to late-1970s, Scott entered into the North Carolina State Hardwood Research Cooperative and, with Dr. Bruce Zobel and Dr. Bob Kellison, established several long rotation hardwood plantations, primarily in bottomland hardwood stands. In the late 1970s, the idea of short rotation hardwood plantations gained notoriety, and we began establishing a sweetgum and sycamore orchard. Also, a sycamore mother tree test was established and thinnings at age 3 and 4 years yielded 10.5 tons/ha/yr and 12.8 tons/ha/year. We were in the midst of an oil crisis again at this time and Tom Kelly, our woodlands manager, calculated that this represented about the BTU equivalent of 16.1 to 19.8 barrels of oil/ha/yr. This began to increase our work on short rotation intensive culture and a biomass study was initiated at our Wildfork Seed Orchard in Monroe County, Alabama.

In the mid-1980s, the oil crises subsided and the project was almost dropped. Hardwood pulp prices similarly started to climb, particularly in the wet winter months when a majority of the hardwood in this region was inaccessible. Some chips from one of our biomass plantations were sent to our fiber quality lab in Philadelphia and the results were promising that we could whole-tree chip these 5-year-old sycamore stands and produce good quality chips for fiber.

These two programs - the biomass harvesting and the Short Rotation Program - have come full circle as they are connected together in the harvesting of these SRIC plantations. Having the resources of the company operating harvesting crews has allowed us to experiment with some harvesting schemes and get good harvesting data and experience, even during the experimental stages of our SRIC program.

We began installing operational plantations in 1988 and currently plant 300 to 400 acres per year. These plantations are located on soils conducive to tree growth but that can be operationally harvested in wet weather. We are also planting some longer rotation sweetgum plantations.

Present Harvesting Operations

We are presently harvesting these stands with our conventional biomass crews, which consist of three 411 Hydro-Ax feller-bunchers, two 450 Timberjack skidders and a 69 cm Morbark mobile chipper. This crew will harvest approximately 250 tons per day. All chips are transported to our Mobile site in closed-top, lightweight wood chip vans by a private trucking contractor.

The Future

The flexibility of small green sycamore creates a problem. Our chipper, with its anvil set at 1.9 cm, generates small twigs 1.9 cm in diameter and 25 to 51 cm long. This doesn't seem to be a big problem for the pulpmill; however, our screen room is fed by volumetric metering bins, and these stems cause choke-ups. We feel the manufacturer of our chipper can help us solve this problem during our present harvest.

On wet ground conditions, our equipment (which use 58 cm tires designed for pre-harvesting tracts) have trouble operating. More needs to be done on larger accumulation-capacity feller-bunchers and pre-haulers or single grip machinery in order to increase efficiency with extremely small stems. Sycamore seems to be very site specific and operational yields do not meet our expectations presently.

Some suggested solutions are site selection and genetic work to provide yields that can be more predictable. Using equipment from one of our logging crews with lower ground pressure tires to harvest the SRIC plantations, while the energy crew equipment is used for logging could also be tried. New equipment designed to harvest small diameter stems on wet sites might be developed.

We are still in the early stages of this system and much work remains to be done. With more and more lands being taken out of production due to regulations (wetlands, endangered species, etc.), our productivity will remain static without coming up with new and innovative ways to increase yield and efficiency while maintaining long-term productivity of our land. We need to continue to ask why or why not?

File posted on March 5, 1996; Date Modified: February 21, 1999