Abstract
Many landowners in the United States have little knowledge of the potential economic returns from agroforestry practices. Economic simulators for temperate agroforestry practices have been generated; yet, there are few data sets on yields of timber and other products to validate and refine such models. The objectives of this study were to characterize variations in nut yields among open canopy eastern black walnut (Juglans nigra L.) trees and apply this information to the development of predictive equations between tree diameter at breast height (DBH) and nut yields. Three data sets were analyzed that included results from Tennessee; Chetopa, Kansas; and Mt Vernon, Missouri. Tree-to-tree variation in nut yields was high within each data set, with coefficients of variation for nut yields typically exceeding 50%. Averaging nut yields over several consecutive years reduced coefficients of variation. Nearly half of the high nut producing trees exhibited an alternate, biennial nut bearing pattern. Trees with low average nut yields had either sporadic or irregular patterns of nut bearing. The regression coefficients for equations relating stem diameter and nut yields varied considerably. Averaging nut yields over consecutive years, and averaging stem diameter and nut yields over a number of trees increased regression coefficients of such equations. These results indicate that predicting nut yields of a tree stand over a several year-period will be easier than predicting yields for a specific tree in a specific year.
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References
A. Ares D. Brauer (2004) ArticleTitleGrowth and nut production of black walnut in relation to sitegenotype and stand management in south-central United States Agroforest. Syst. 63 83–90
J.E. Bergez M. Etienne P. Balandier (1999) ArticleTitleALWAYS: a plot-based silvopastoral model Ecol. Model. 115 1–17 Occurrence Handle10.1016/S0304-3800(98)00153-7
H.E. Garrett W.B. Kurtz (1983) ArticleTitleSilvicultural and economic relationships of integrated forestry-farming with black walnut Agroforest. Syst. 1 245–256 Occurrence Handle10.1007/BF00130610
Hammons Products, Co. 2004. Crop updateNovember 13, 2003. [on-line] www.blackwalnuts.com/page.asp?category=information&subcategory=cropupdate. Verified September 3, 2004.
J.E. Jones J. Haines H.E. Garrett F.F. Loewenstein (1995) ArticleTitleGenetic selection and fertilization provide increased nut production under walnut-agroforestry management Agroforest. Syst. 29 265–273 Occurrence Handle10.1007/BF00704873
Kincaid W.H. 1982. Silvicultural economic assessment of black walnut management alternatives. MS thesis, University of Missouri, Columbia, 99 pp.
Microsoft Corporation. 1999. Microsoft Excel for windows, Microsoft Office 2000, Version 09.00.3822.
New Zealand Forest Research Institute 1994. AEM User Guide Version 3.0. FRI Software Series No. 12. Rotorua, New Zealand.
F. Ponder J.E. Jones (2001) ArticleTitleAnnual applications of NP and K interrupt alternate-year nut crops in black walnuts J. Plant Nutr. 24 661–670 Occurrence Handle1:CAS:528:DC%2BD3MXktlOlsbs%3D
A. Raedeke J.J. Green S.S. Hodge C. Valdivia (2003) ArticleTitleFarmers, the practice of farming and the future of agroforestry: an application of Bourdieu’s concepts of field and habitus Rural Sociol. 68 64–86
Reid W., Coggeshall M.V. and Hunt K.L. 2004. Cultivar evaluation and development for black walnut orchards. In: Michler C.H., Pijut P.M., van Sambeek J.W., Ciggeshall M.V., Seifert J., Woeste K., Overton R. and Ponder F. (eds) Proceedings of the 6th Walnut Council Research Symposiumnc-243, U.S.D.A. Forest service, North Central Research Station, St. Paul, MA, USA, pp. 18–24.
SAS Institute. 1989. SAS/STAT user’s guide. Version 6. 4th ed. Volume 2. SAS Institute Inc., Cary, USA.
Schmidt T.L. and Kingsley N.P. 1997. Status of black walnut in the United States. Gen. Tech. Rep. NC-191, U.S.D.A Forest Service, North Central Forest Experiment Station, St. Paul, MN, USA, pp. 9–22.
G. Simioni X. Le Roux J. Gignoux H. Sinoquet (2000) ArticleTitleTREEGRASS; a 3D process-based model for simulating plant interactions in tree-grass ecosystems Ecol. Model. 131 47–63 Occurrence Handle10.1016/S0304-3800(00)00243-X
D. Sparks (1997) ArticleTitleA model for predicting pecan production under arid conditions at high elevations J. Am. Soc. Hortic. 122 648–652
A.L. Thomas D. Brauer J.L. Rhoades J.P. Slusher (2003) ArticleTitleLong term effects of tall fescue cover on black walnut growth and nut production Proceedings of the 8th North American Agroforestry Conference 8 342
T.H. Thomas R.W. Willis J. Winterbourne J.H. Samuel (1994) ArticleTitleBio-economic agroforestry modelling: the BEAM project Agroforest. Forum 5 65–72
J.G. Woodroof (1979) Tree Nuts: Production, Processing, Products EditionNumber2 AVI Publishing Company, Inc. Westport CT, USA 732
G.C. Wright J.B. Storey M.K. Harris P.T. Sprinz (1990) ArticleTitlePre-harvest pecan yield estimation HortScience 25 698–700
T.G. Zarger (1946) ArticleTitleYield and nut quality of the common black walnut in the Tennessee Valley Ann. Rep. North. Nut. Grow. Assoc. 37 118–124
T.G. Zarger (1956) ArticleTitleStatus of tree crop investigations in the Tennessee Valley region Ann. Rep. North. Nut. Grow. Assoc. 47 57–68
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Brauer, D., Ares, A., Reid, W. et al. Nut-yield Variations and Yield–diameter Relationships in Open-canopy Black Walnut Trees in Southern USA. Agroforest Syst 67, 63–72 (2006). https://doi.org/10.1007/s10457-005-1705-0
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DOI: https://doi.org/10.1007/s10457-005-1705-0