Scientia Horticulturae 192 (2015) 60–69 Contents lists available at ScienceDirect Scientia Horticulturae journal homepage: www.elsevier.com/locate/scihorti Effect of olive hedgerow orientation on vegetative growth, fruit characteristics and productivity Eduardo R. Trentacoste a,b,∗ , David J. Connor a,c , María Gómez-del-Campo a a Dpto. de Producción Agraria, Universidad Politécnica de Madrid, Cdad. Universitaria s/n, Madrid 28040, Spain b Estación Experimental Agropecuaria Junín (Instituto Nacional de Tecnología Agropecuaria), Mendoza 5573, Argentina c Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Victoria 3010, Australia a r t i c l e i n f o Article history: Received 10 March 2015 Received in revised form 11 May 2015 Accepted 15 May 2015 Keywords: Olea europaea L. Hedgerow design Flowering Oil yield profiles Fruit water content Ripening index a b s t r a c t The effect of row orientation on oil production and fruit characteristics was studied, during years 3–6 after planting of the super-high density olive hedgerows (1923 tree/ha) planted at the same row spacing (4 m) in four orientations (N–S, NE–SW, NW–SE and E–W). During the last two years of observations the hedgerows were maintained by lateral pruning and topping at the same row width (1 m) and height (2.5 m). In those years, maximum fruit yield was achieved by NE–SW and NW–SE (15.7 t/ha). Of these, NE–SW achieved the highest oil yield (2.7 t/ha). There were no differences in fruit or oil yield between N–S (2.5 t oil/ha) and E–W (2.3 t oil/ha) orientations. Fruit density was the most important component to explain these differences, by previous influence on number of buds developed and fruit set. Analyses of profiles of yield components and yield on opposing sides of hedgerows revealed many differences that contributed to overall hedgerow performance. Regardless of row orientation, fruit density was highest from 1.0 to 2.0 m height, decreasing to the top and to the base. In both sides of N–S and also in N side of the E–W hedgerows, fruit weight decreased linearly from top to base, whereas on both sides of NE–SW and NW–SE and S side of E–W hedgerows, fruit weight decreased linearly from the top layer to 1.4 m height and remained stable to depth. Fruit ripening was also highest in the top layers and decreased linearly to the base in all orientations, but was more evenly distributed in the S and SW sides of E–W and NW–SE hedgerows. Fruit water content increased linearly from top to base in all orientations, more sharply in NE–SW, NW–SE and N–S hedgerows. The discussion explores the role of light relations in the determina- tion of yield in olive hedgerows and options for future study and selection of optimal hedgerow designs. © 2015 Published by Elsevier B.V. 1. Introduction Worldwide, most olive area remains characterized by old, widely spaced trees (between 100 and 300 trees/ha), trained to vase structure, and grown under rain-fed conditions. Productivity is low and the high demand for manpower for harvest and pruning (Vieri and Sarri, 2010) compromises the international competitive- ness of olive compared with alternative vegetable oils. In response, growers have recently begun to establish new olive orchards in hedgerows to allow mechanical harvesting and so reduce the costs of manual labour while also allowing more rapid and timely man- agement interventions (Connor et al., 2014; Tous et al., 2010). Two types of hedgerow have emerged suited to available mecha- nized over-row, canopy-contact harvesters. The first are hedgerows ∗ Corresponding author at: Dpto. de Producción Agraria, Universidad Politécnica de Madrid, Cdad. Universitaria s/n, Madrid 28040, Spain. fax: +34 913365406. E-mail address: trentacoste.eduardo@inta.gob.ar (E.R. Trentacoste). planted at high tree density (1500–2000 trees/ha) that are main- tained around 2.5 m high and 1.0–1.5m wide to suit the dimensions of modified grape harvesters. These orchards have expanded in environments where olive shows moderate-low vegetative vigour in Spain, Chile and Portugal (León et al., 2007; Rius and Lacarte, 2010) and are usually called “superintensive” orchards. The second are large hedgerows, planted at 250–500 trees/ha and maintained around 4.5 m high and 4 m wide. A large harvester, “the Colossus”, was developed for these so-called “intensive” orchards that have expanded in production zones where olive grows vigorously in Argentina and Australia (Cherbiy-Hoffmann et al., 2012; Ravetti, 2008). The design and management of hedgerow orchards has improved mainly through trial and error by commercial growers, while adequate scientific research in olive hedgerow remains very limited (Cherbiy-Hoffmann et al., 2012; Connor et al., 2014; Pastor et al., 2007; Tombesi and Farinelli, 2014). Row orientation is a major aspect in the design of these plant- ing systems and yet its influence on olive oil production and fruit characteristics has not been well studied. In practice, N–S oriented http://dx.doi.org/10.1016/j.scienta.2015.05.021 0304-4238/© 2015 Published by Elsevier B.V.