Influence of phytotechnology on growth, production and leaf area index of black walnut (Juglans nigra L.) monocultures in Slovakia
Tokar, F.(Slovenska Akademia Vied, Nitra (Slovak Republic). Ustav Ekologie Lesa)E-mail:[email protected] | Krekulova, E.
We evaluated the influence of crown thinning with positive selection, different intensity (moderate PRP III and heavy PRP IV) and 5-year frequency on growth, production, quality and leaf area index of three Juglans nigra monocultures from 1978 to 2003. The trends of development of mean stem, basal area, standing volume and aboveground dendromass (in dry matter) were mainly influenced by heavy crown thinning. The total production was also significantly influenced by heavy thinning. In comparison with the control, the total mean increments of basal area and volume were both higher by 24%, respectively, that of weight by 16%. The leaf area index ranged from 6.54 ha/ha (PRP III) to 7.82 ha/ha (PRP V). Dendrochronological analyses revealed minimum widths of annual rings in the years 1952, 1961, 1968, 1971, 1975, 1981, 1983, 1985, 1993, 2000, maximum ones in 1951, 1957, 1959, 1967, 1974, 1979, 1982, 1984, 1989, 1999.
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