Chapter 8. The Evolution of Pine Plantation Silviculture in the Southern United States Thomas R. Fox, Eric J. INTRODUCTION 1 Jokela, and H. Lee Allen ine (Pinus spp.) plantation silviculture in the Southern United States is one of the major P success stories for forestry in the world. In 1952, there were only 1.8 million acres of pine Abstract—In the 1950s, vast acreages of cutover plantations in the South (fig. 8.1), containing 658 63 forest land and degraded agricultural land existed million cubic feet of timber (U.S. Department in the South. Less than 2 million acres of southern of Agriculture, Forest Service 1988). At the turn pine plantations existed at that time. By the end of the 21st century, there are 32 million acres of of the 20th century, there were 32 million acres of pine plantations in the South that contain 23.9 southern pine plantations in the Southern United billion cubic feet of timber (Wear and Greis 2002). States, and this region is now the woodbasket Perhaps more remarkable is the significant of the world. The success story that is southern increase in productivity that occurred during pine forestry was facilitated by the application of this period (fig. 8.2). Mean annual increment of research results generated through cooperative pine plantations has more than doubled, and work of the U.S. Department of Agriculture Forest rotation lengths have been cut by > 50 percent. Service, southern forestry schools, State forestry The success of pine plantation silviculture has turned the South into the woodbasket of the agencies, and forest industry. This chapter reviews United States (Schultz 1997). the contributions of applied silvicultural research in land classification, tree improvement, nursery These remarkable changes in the last 60 years management, site preparation, weed control, and were the result of a variety of factors that came fertilization to plantation forestry in the South. together at the end of World War II. Economic These practices significantly increased productivity factors, including a declining agricultural economy coupled with a rapidly expanding pulp and paper of southern pine plantations. Plantations established industry based on southern pine, combined to in the 1950s and 1960s that produced < 90 cubic provide the impetus for the large increase in feet per acre per year have been replaced by southern pine plantations. The success of this plantations established in the 1990s that are effort was due in large part to the cooperative producing > 400 cubic feet per acre per year. research and technology transfer efforts of many Southern pine plantations are currently among organizations, including the U.S. Department of the most intensively managed forests in the world. Agriculture Forest Service (Forest Service), State Growth of plantations managed using modern, forestry agencies, forestry programs at southern integrated, site-specific silvicultural regimes rivals universities, and forest industry. that of plantations of fast-growing nonnative The objectives of this chapter are to describe species in the Southern Hemisphere. Additional the evolution of southern pine plantation gains in productivity are likely as clonal forestry silviculture over the last 50 years and to outline is implemented in the South. Advances in forest our view of the current state of the art of pine biotechnology will significantly increase growth plantation silviculture in the South. Rather than and quality of future plantations. It appears likely present an exhaustive review of the literature, that the South will remain one of the major wood-producing regions of the world. 1 Associate Professor of Forestry, Virginia Polytechnic Institute and State University, Department of Forestry, Blacksburg, VA 24061; Professor of Forestry, University of Florida, School of Forest Resources and Conservation, Gainesville, FL 32611; and C.A. Schenck Distinguished Professor of Forestry, North Carolina State University, Department of Forestry, Raleigh, NC 27695, respectively. 35 30 Figure 8.1—Number of 25 acres of pine plantations in the Southern United 20 States from 1952 to 15 1999 (data from U.S. 10 (million acres) Department of Plantation area Agriculture 1988, 5 Wear and Greis 2002). 0 1952 1962 1970 1977 1985 1999 Year 250 60 Total yield Pulpwood rotation age 200 50 40 64 150 Figure 8.2—Estimated 30 total yield and pulpwood 100 rotation age in pine 20 plantations in the 50 10 Southern United States Rotation age (years) from 1940 through 2010. yield (tons per acre) Total 0 0 1940 1950 1960 1970 1980 1990 2000 2010 Productivity Year Clonal and biotech Site preparation Tree improvement Planting Weed control Natural stand Southern Forest Science: Forest Southern Fertilization Past, Present, and Future Present, Past, 250 200 Figure 8.3—Estimated 150 contributions of intensive management practices to 100 productivity in pine plantations in the (tons per acre) Volume at harvest Volume 50 Southern United States from 1940 through 2010. 0 1940 1950 1960 1970 1980 1990 2000 2010 Establishment period we will highlight what we believe are the major of cotton and tobacco, which were the most advances during the last 50 years and illustrate important agricultural crops throughout the their contribution to the productivity gains that South (Bennett 1939). Declining soil productivity have been observed during this time (fig. 8.3). As due to erosion, accompanied by low prices for cash part of this, we hope to demonstrate the significant crops and pest problems such as the boll weevil contributions that applied coop-erative research (Anthonomus grandis grandis), caused large has made to this success story. amounts of agricultural land to be abandoned throughout the South between the end of the SETTING THE STAGE FOR PLANTATION Civil War and World War II. FORESTRY IN THE SOUTH The South has been an important source of learing of forests for crop production occurred timber and forest products since colonial times throughout the Coastal Plain and Piedmont (Williams 1989). Other than timber for local use, Cfrom the colonial period until the beginning the first major products from southern forests of the Civil War (Williams 1989). In Virginia > 25 were naval stores from longleaf pine (P. palustris million acres, or 47 percent of the total land area Mill.) and ship timbers from live oak (Quercus in the State, had been cleared by 1860. Soil erosion virginiana Miller) (Butler 1998, Williams 1989). was a serious problem associated with production The production of lumber in the South increased Commenting on the situation in the 1950s, gradually following the Civil War and more Wahlenberg (1960) stated, “Much land suitable dramatically beginning in the 1880s and 1890s, for loblolly pine that has been made unproductive when available timber in the Lake States was through heavy cutting, wildfire, natural depleted. Between 1890 and 1920, the South was catastrophe, or abandonment of agriculture is in the major lumber-producing region in the country. need of planting.” Wakeley (1954) estimated that Production peaked at approximately 140 billion there were 13 million acres of land requiring board feet in 1909, when the South produced 46 planting in the South in 1950. percent of all timber cut in the United States Tree planting in the South, which had nearly (Williams 1989). After 1909, lumber production ceased during World War II, rapidly increased in declined gradually until the start of the Great the years immediately following the war (U.S. Depression in 1929, when production fell sharply. Department of Agriculture, Forest Service 1988). The discovery by Charles Herty that acceptable A large percentage of this planting occurred on pulp and paper could be made from southern farmland associated with the Soil Bank Program 65 pine had a dramatic impact on southern forestry of the 1950s. The successful reforestation of beginning in the 1930s (Reed 1995). A rapid abandoned and degraded agricultural land increase in the pulp production in the South illustrated the conservation value of trees and followed this discovery (Josephson and Hair 1956). their role in reducing soil erosion and improving Numerous pulp and paper mills were constructed water quality (Bennett 1939). The rapid expansion throughout the South during the 1930s, increasing of the pulp and paper industry in the South during 8. Chapter the demand for smaller diameter southern pine the 1930s increased the demand for pine pulpwood timber. Pulp and paper companies purchased large and stimulated planting on forest industry land. tracts of timberland during this period to provide By this time, the superior growth and yield of pulpwood for these new facilities (Williams 1989). pine plantations relative to naturally regenerated stands had become evident. For example, the At the start of the 20th century, almost no effort original plantations established by Great Southern was devoted to reforestation following timber Lumber Company clearly showed the potential Silviculture Pine Plantation harvest (Williams 1989). Destructive fires often value of fully stocked plantations compared to the followed logging, killing much of the natural poorly stocked naturally regenerated stands that regeneration that might otherwise have become were the norm at the time (Wakeley 1954). established on many cutover tracts. During the 1920s, the Forest Service recognized the need NURSERY PRACTICES AND for large-scale tree planting in the South and SEEDLING HANDLING began a research program to address reforestation issues. The first large-scale planting of southern rtificially regenerating the large pine occurred between 1920 and 1925 when the acreages found in the South required an Great Southern Lumber Company planted A abundant supply of high-quality seedlings. A approximately 7,000 acres near Bogalusa, LA concerted research effort of the Forest Service on (Wakeley 1954). During the 1920s, the Forest reforestation in the South began in the 1920s and Service also began its reforestation program in culminated with the publication of Agricultural the South with the planting of 10,000 acres in the Monograph 18 “Planting the Southern Pine” Sumter National Forest in South Carolina.