Stručni rad

Regeneration of Floodplain Forests in the Croatian Podunavlje Region Combined with Planting Seedlings of Narrow-Leaved Ash (Fraxinus angustifolia Vahl.)

Željko Mayer ; Hrvatske šume UŠP Vinkovci
Željko Hećimović ; Hrvatske šume UŠP Vinkovci

Sažetak

The paper explores the possibility of generative and vegetative natural regeneration of Euro-American poplar cultures (Populus × canadensis Moench and P. deltoides W. Bartram ex Marshall), either with seeds or from sprouts and stumps of autochthonous black and white poplars (Populus nigra L. and P. alba L.) and white willow (Salix alba L.), combined with planting narrow-leaved ash (Fraxinus angustifolia Vahl). After the seventh year of plantation age and the applied tending and cleaning treatments in the stand, the dominant layer features narrow-leaved ash (7.86 m), white poplar (8.66 m) and white willow (8.64 m), while the subordinate layer contains “American” ash (Fraxinus americana L. and F. pennsylvanica Marshall), boxelder (Acer negundo L.), spreading elm (Ulmus laevis Pall.), black and white mulberry (Morus nigra L. and M. alba L.) and other species.
Following the final cut of “Euro-American” poplars (Populus × canadensis Moench. and P. deltoides W. Bartram ex Marshall), it is possible to raise a natural stand of black poplar (Populus nigra L.), white poplar (Populus alba L.) and white willow (Salix alba L.) combined with narrow-leaved ash (Fraxinus angustifolia Vahl). The regeneration period lasts somewhat longer, but the rotation will also be longer, because narrow-leaved ash and autochthonous poplars and willow are longer-lived than the clones of Euro-American poplars. This will make it possible to achieve natural succession of floodplain forests, thus obtaining the paraclimatic community Fraxino-ulmetum laevis Slav. 52 Salicion (Soo) Oberd 53.
By complementing a natural forest with narrow-leaved ash (Fraxinus angustifolia Vahl.) we have enriched the vegetation of floodplain forests and accelerated the process which would occur anyway. It is also possible to plant pedunculate oak (Quercus robur L.), but this requires more care and time, but also better and drier sites. Black poplar is hard to raise naturally since this species is more demanding. It requires much more care and well prepared soil for the seeds. This, however, should not cause concern as a black poplar selection programme is currently under way (Osijek Forest Administration in cooperation with the Faculty of Forestry in Zagreb, Department of Forest Genetics, Dendrology and Botany), so that it will be possible to introduce it via planting material, similar to narrow-leaved ash. We recommend that, after the final cut of the Euro-American poplar, the site be prepared for natural regeneraton with autochthonous black and white poplar and white willow. The introduction of good-quality two-year-old seedlings of narrow-leaved ash (1,111 pcs/ha – planting distance 3 x 3 m), pedunculate oak and black poplar (up to 100 pcs/ha – planting distance 10 x 10 m) will improve the natural stand.
In the first, or possibly second year of plantation age, the young growth should be tended by freeing the young trees from luscious vegetation and from dewberry (Rubus caesius L.) in particular. In the fourth of the fifth year the saplings should be cleaned. In the meantime climbers should be removed; common grape vine (Vitis vinifera L.) ss. sylvestris /C.C. Gmel./ Berger), common hop (Humulus lupulus L.), clematis (Clematis L.) and others. Tending with thinning follows depending on the developmental stage of the stand until the final cut and resumed natural regeneration. Apart from the above mentioned species in the dominant layer, “American” ash (Fraxinus americana L., F. Pennsylvanica Marshall), boxelder (Acer negundo L.), spreading elm (Ulmus laevis Pall.), white and black mulberry (Morus alba L. and M. nigra L.) should be left in the subordinate layer, as well as other species that sporadically occur on river islands and in

Ključne riječi

Croatian Podunavlje region; floodplain forests; narrow-leaved ash

Hrčak ID:

24053

URI

https://hrcak.srce.hr/24053

Datum izdavanja:

29.2.2008.

Podaci na drugim jezicima: hrvatski

Posjeta: 2.792 *