DIGITALNA ARHIVA ŠUMARSKOG LISTA
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ŠUMARSKI LIST 1-2/1966 str. 169     <-- 169 -->        PDF

78—92´% and 32—70% respectively. In Pinus nigra in the first two Republics the
established grafts were 68—70%, while in Macedonia only 6—21´%, etc. The effect
of air dryness, viz. insufficient relative air humidity on the percentage of successful
grafts is visible from the above-mentioned numbers. This was proved also by experiments
in the SR of Macedonia at two elevations, viz. 640 and 1250 m. In Abies
alba and Pinus peuce in a dry year successful were at the first elevation 32% and
21´% grafts, while at the second 70% and 52% respectively. In a humid year at the
altitude of 640 m. the percentage of successful grafts was 54% and 55%, while at
1250 m. 79% and 92% respectively. In both the mentioned years the grafting was
carried out at the same time, i. e. in the second half of April.


In conifer grafting work were made experiments with scions cut during winter
and kept in pits with ice, as well as with scions cut just prior to the grafting (April).
The results varied. However, on an average, better results were achieved with winter-
cut scions if they were correctly preserved until use.


In the broadleaved species the grafting was done on Turkish Hazel (Corylus
colurna L.). It become evident that the success depended on the developmental stage
(phenophase) of the rootstock, the grafting method and time, and the individual characters
of the parent trees. With Walnut were obtained satisfactory results when
grafting green scions (Serbia).


Under the conditions of an arid climate achieved were in individual species
varying successes with different methods of grafting. Thus with Pinus peuce was
obtained a higher percentage of successful grafts with the »side grafting« and the
»whip grafting« than with other methods, while with Fir better results were achieved
by means of sied union without cutting off the stock top.


Experiments were made to root cuttings of European Larch (Croatia). The first
results are suggestive of possibilities for further work.


2. Formation of living archives
The works are in the initial stage. Planted was the understock, performed were
the first graftings, etc. Almost all research institutions took up the formation of
living archives. The Institute for Conifers, Jastrebarsko, is forming a central living
archives for coniferous species. Planted are already clones for Larix leptolepis and
Pseudotsuga taxifolia var. viridis on an area of one hectare. The Institute for Forestry
and Timber Industry, Beograd, is establishing two Beech archives of 1.0 ha.,
two Oaks archives of 1.0 ha., and one Locust-tree archives of 0.1 ha. The Institute
for Forestry and Timber Industry, Ljubljana, has laid out living archives of 12
grafted Beech, trees, 56 grafted Spruce trees, 33 grafted Austrian Pine trees, and
45 grafted Fir tees. The Forestry Institute, Skopje, in establishing small-sized archives
from 5 to 10 clones of Fir, Macedonian pine, Birch, Pedunculate Oak, and Oriental
Plane. The Poplar Institute, Novi Sad, established a Populetum with 175 various
Poplar species and types.


3. Establishment of seed orchards
The laying out of seed orchards began in 1960, and a somewhat more intensive
activity has been felt in recent years. The seed orchards being established are intended
to be of an experimental character and serving as a model for forestry practice.
In Table 5 are given data on seed orchards by tree species and the institutions
which are establishing them.


Until now completely finished is only the seed plantation of Fraxinus angustifolia
Vahl. in which works started in 1960. As to other seed plantations, works are
in progress. The seed orchards are laid out for 20—30 clones arranged by the usual
methods. The rootstocks are planted in 5 x 5 m. and 7 x 7 m. spacings. Chosen are
locations with adequate warmth and insolation of the site. Interesting was a suggestion
to lay out the seed orchards outside the natural range of the species, i. e. in
southern regions of this country because of more favourable light and warmth conditions
and the possibility of a higher seed production (11).


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