Abstract

ARREOLA AVILA, J. G. et al. Sunlight availability and nut production after removing pecan trees. Rev. Chapingo ser. cienc. for. ambient [online]. 2010, vol.16, n.2, pp.147-154. ISSN 2007-4018.  https://doi.org/10.5154/r.rchscfa.2009.11.047.

The volume of well-illuminated canopy is one of the main factors in the productivity of pecan trees. When mature pecan orchards with high densities (at least 100 trees per hectare) become overcrowded, photosynthetic active radiation penetration within the tree canopy, growth and nut production are affected adversely. Little research has been done to determine the effect of thinning on available sunlight and productivity of a pecan orchard. The objective of this study was to determine the effect of tree thinning on photosynthetic active radiation (PAR) available within permanent pecan trees, shoot growth, nut production and nut quality. This study was carried out in a mature pecan orchard thinned at different stages from 25 to 50 % during the 2004-2008 period. Available PAR within pecan trees, shoot growth, and nut production per tree were affected by thinning treatments; however nut quality (kernel percentage) per tree during the three-year period of the study was not significantly affected. The results of this study indicate that a gradual thinning in overcrowded pecan orchards could be done in order to recover growth and production components.

Keywords : Tree thinning; sunlight penetration; shading; nut yield; kernel percentage.