|Brauer, David - Dave|
Submitted to: Agroforestry Systems
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/2/2005
Publication Date: 3/1/2006
Citation: Ares, A., Reid, W., Brauer, D.K. 2006. Production and economics of native pecan silvopastures in central United States. Agroforestry Systems. 66:205-215. Interpretive Summary: Silvopastoral practices with native pecans (Carya illinoinensis) are an important land use for floodplains in southern and central regions of the United States, however, declining nut prices threaten the sustainability of this practice. We examined nut, forage, and timber production as well as economics of managed pecan systems in southeastern Kansas. Economic simulations obtained with the Agroforestry Estate Model indicated that the system economic outputs are highly sensitive to pecan nut price and maximum income is generated when beef, nuts and timber are sold. These results are of interest to landowners and natural resource professionals who work with landowners because they provide an indication of the system's potential profitability.
Technical Abstract: Riverine silvopastoral practice with native pecan (Carya illinoinensis) are a suitable land use for southern and central regions of the United States. However, a detail examination of the profitability of this practice has not been reported recently. We examined nut, timber and forage production to determine the economics of managed pecan silvopastures in southeastern Kansas. During 1981-2000, annual hulled nut production varied between 50 and 1,600 kg/ha in stands averaging 72 years of age, and ranging in density between 35 and 74 trees/ha. The nut crop had a clear pattern of biennial bearing. Tree stem diameter and stand basal area increased linearly with time. Nut production was not related to stand age or increased tree density, suggesting that nut production had reached a steady state level. Merchantable timber yield ranged between 0.25 and 1.35 cubic meters/ha/yr. In pecan silvopastures with a mean tree age of 37 years, forage production varied between 1,500 and 4,600 kg DM/ha in 2001 and 2002. In 2001 only, grass production decreased with decreasing solar radiation in a range of 0.25 to 0.83 of fraction light transmitted. In both years, the grass understory had acceptable quality for cow-calf production with average crude protein content between 9 and 11.8% and no evidence of excessive levels of ergoalkaloids from tall fescue. Twenty-seven vascular plants were identified in the understories of which nut sedge, tall fescue, wild oat and Canadian wild rye were the most abundant. Economic simulations obtained with the U.S. Agroforestry Estate Model indicated pecan nut price is the main variable driving economic outputs under current production conditions. Annual cash flows from nut sales had smaller fluctuations than nut yields because of an inverse relation between nut price and yield. Improved timber production appears an option for increasing system profitability.