TIME OF SHADING INFLUENCES YIELD, NUT QUALITY, AND FLOWERING

A.N. Azarenko, R.L. McCluskey, C.R. Hampson
Five-year -old self rooted ‘Willamette’ hazelnut trees were enclosed entriely with 63% black shade cloth for five 6-week intervals beginning 5 April and ending 30 September. Yiled and nut size and quality data were obtained after the growing season. Catkin and cymule flower number were counted in February and flower densities calculated. Yileds were reduced by 25 % with the mid-season shading (23 May - 3 July). Yield efficiency was reduced by a similar degree by shading during this period and the next 6 week shading period. These two periods were apparently critical for nut size since a 10% reduction in average nut weight was observed. Only 20 % large nuts were produced in contrast to 64 % in unshaded controls when trees were shaded mid-season. There was an increase in poorly filled, shriveled, and moldy kernels from trees shaded during the last two periods from 4 July - 30 September. The density of catkin, and total female and female flowers borne of catkin peduncles was reduced when trees were shaded during the three 6- week periods from 23 May -30 September by approximately 32 %, 35 % and 50 %, respectively. The light environment within a hazelnut canopy must be managed to optimize yields, nut quality and flowering.
Azarenko, A.N., McCluskey, R.L. and Hampson, C.R. (1997). TIME OF SHADING INFLUENCES YIELD, NUT QUALITY, AND FLOWERING. Acta Hortic. 445, 179-184
DOI: 10.17660/ActaHortic.1997.445.24
https://doi.org/10.17660/ActaHortic.1997.445.24

Acta Horticulturae