IFEVA   02662
INSTITUTO DE INVESTIGACIONES FISIOLOGICAS Y ECOLOGICAS VINCULADAS A LA AGRICULTURA
Unidad Ejecutora - UE
artículos
Título:
Weeds in Eucalyptus globulus subsp. maidenii (F. Muell) establishment: effects of competition on sapling growth and survivorahip.
Autor/es:
GARAU, A.M.; GHERSA, C.M.; LEMCOFF, J.H.; BARAÑAO, J.J,
Revista:
NEW FORESTS
Editorial:
SPRINGER
Referencias:
Año: 2009 p. 251 - 264
ISSN:
0169-4286
Resumen:
Abstract: The effect of herbaceous vegetation on growth and survival was assessed in planted eucalyptus saplings grown under four levels of weed cover. Seedlings of  Eucalyptus globulus subsp. maidenii were planted with 0 (W0), 25 (W25), 50 (W50) and 100%  (W100) weed cover. Weed species composition and above ground biomass was determined. Soil water content was evaluated by the gravimetric method. Seedling leaf area, diameter and height were evaluated at planting and during the 3 months following establishment. Tree height, diameter and stem volume was estimated at 12, 24 and 36 months. First year tree survival was recorded. The ratio of cumulative stem growth under W100: cumulative stem growth under W0 was used to measure competitive performance. Regression analysis was used to determine competition thresholds. Weeds seriously threaten the growth of E. globulus subsp. maidenii. Early negative effects of competition on growth were evident as from the second month after establishment, and both seedlings and 1-year-old saplings were more affected than 2- and 3-year-old ones. A ‘‘minimum-response threshold’’ was determined near 500 kg/ha (corresponding to W25 cover). No clear effect was found between sapling survival and weed biomass.