Large-scale comparison of reforestation techniques commonly used in the lower Mississippi alluvial valley: first year results

Abstract

In the Lower Mississippi Alluvial Valley (LMAV), restoring bottomland hardwood forests has attracted heightened interest. The impetus involves not only environmental and aesthetic benefits, but also sound economics. Financial incentives to restore forested wetlands in the LMAV can come from federal cost share programs such as the Conservation Reserve Program and the Wetlands Reserve Program (WRP), which provide easements and funding to cover planting costs. Forestry led Mississippi agriculture production in 1995, testimony to the importance of timber. This project is designed to test four restoration techniques and includes methods outlined by both federal program guidelines and by industry. The four techniques being tested are: (1) Eastern cottonwood (Populus deltoides Marsh.) as a nurse crop for Nuttall oak (Quercus nuttallii Palmer), (2) planting bareroot Nuttall oak seedlings, (3) direct seeding Nuttall oak acorns and, (4) natural, old field succession. A former farmland in Sharkey County, MS, was chosen as the study area because it represents edaphic and hydrologic conditions frequently encountered in economically marginal cropland in the LMAV. A randomized complete block design was used with three replications. Block size was 32 hectares, allowing for four 8 ha treatment plots. All planting was completed by March 1995, except for the interplanting of oak in the cottonwood, which will occur in year 3. Acorns were sown in May 1995. Sample plots were measured in fall 1995. Survival after one growing season averaged 92% for cottonwood, 63% for planted oak seedlings, and 11% for oak germinants. No trees were found in the natural succession plots. Number of stems per ha averaged 793 for cottonwood, 467 for seedlings and 284 for germinants. Average height of cottonwood after the first growing season was 2.1 meters, seedling height was 0.4 m, and germinant height was 0.1 m. There was variability between blocks, and seedling damage by rodents was prominent. Tree planting on land enrolled in the WRP is considered successful for wetland restoration purposes if 309 live trees per ha are present after three-growing seasons. After 1 year, both the cottonwood and oak plantings resulted in stocking that could meet these standards. Although the stocking mandated by WRP was not met for the direct seeded oak after one growing season, delayed germination may increase stocking. In addition to providing wildlife habitat, the high survival rate and rapid growth of the cottonwood will enable harvest in 10 years, generating income in a relatively short time period. Further evaluation of tree growth and survival under these restoration techniques will allow for a more definitive conclusion on their feasibility and attractiveness to landowners.

Citation

Schweitzer, Callie J.; Stanturf, John A.; Shepard, James P.; Wilkins, Timothy M.; Portwood, C. Jeffery; Dorris, Lamar C., Jr. 1997. Large-scale comparison of reforestation techniques commonly used in the lower Mississippi alluvial valley: first year results. In: Pallardy, Stephen G.; Cecich, Robert A.; Garrett, H. Gene; Johnson, Paul S., eds. Proceedings of the 11th Central Hardwood Forest Conference; Gen. Tech. Rep. NC-188. St. Paul, MN: U.S. Department of Agriculture, Forest Service, North Central Forest Experiment Station: 313-320