DIGITALNA ARHIVA ŠUMARSKOG LISTA
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ŠUMARSKI LIST 1-2/1990 str. 64 <-- 64 --> PDF |
2990 ha. The raising of arborescent willow plantations has been intensified due primarily to the establishment of collections of clones, selected and verified through a series of experiments. The sites, on the Danube islands, where the success of three clones in established plantations age 4—16 and 225 ha has been assessed, can be divided into 5 site qualities, which are related to the following plant comunities (biotopes): I Galio-Salicetum albae Rauš 73 II Populetum nigro-albae Slav. 52 III Šalici Populetum nigrae Tx. 31 (Meijer — Drees 36) rubetosum caesii Rauš 73 IV Salicetum purpureae Wend. — Zeil. 52, Scirpo-Phragmitetum W. Koch 26 et Uligines V Paludes In order to increase the wood mass production in arborescent willow plantations, the following principles should be adhered to: 1. For each site quality, the optimal clone mixture has to be selected, showing a specific adaptation to that particular site. 2. Plantations should be multi-clonal. 3. The arrangement of clones in plantations should be mosaic (in groups) in order to alleviate competiton between clones. 4. Plantation spacing on site quality I, II and III should be 4 x 4 m, possibly with one inter-row of same clone, with 2 m spacing. Felling of trees in the inter- row should be done after 8—10 years, while the rotation of remaining plantation trees, at 4 x 4 m spacing, would be 20 years for purposes of log production. On other sites we recommend 3 x 3 m spacing. 5. On site quality I and III (site quality II is relatively dry for willow!), low- cost technology for plantation raising may be applied: by means of one-year twigs, while on all other sites we recommend that strong rootings or sticks of 2/2 and 2/0 age be used. 6. On heavy, flooded and weed-grown sites along the Sava River, willow plantations "may serve as pioneer plantations, as they facilitate reforestation with more valuable broad-leaved species (Fraxinus angustifolia, Quercus robur) on clearings and devastasted parts within the existing hardwood broad-leaved stands. |