DIGITALNA ARHIVA ŠUMARSKOG LISTA
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 ŠUMARSKI LIST 1-2/1966 str. 95     <-- 95 -->        PDF This will give rectangular plots 4,20 X 8,40 m = 35,28 m2 for pine andsquare plots 6 X 6 m = 36 m2 for spruce. With the 8 replicates planned eachprovenance will cover 282,24 m2 and 288,0 m2 for a pine and spruce plantationrespectively. Thus on a site of 5 ha it will be possible to include about 170provenances. Smaller number of provenances will require a relatively smallerarea.In Table 1 the number of trees per plot at different ages is given for pineand spruce. The number of trees per ha. at different ages shown in Table 1were taken from Schwappach´s yield tables (1943) for the best site class. Onpoorer sites there will be more trees per ha.Table 1Number of trees per hectare and per plot at different ages for pine and spruceAge,yearsPin eper ha.1.20 X 0.60 m.per plot 35.22 sq. m.Spruc eper ha.1 X 1 m.per plot 36:1 14,000 49 10,000 3625 4,380 15.5 5,110 18.430 2,880 10.0 3,702 13.335 2,080 7.3 2,800 10.040 1,570 5.5 2,210 7.95(1 998 3.5 1,468 r>.´i60 739 2.6 1.037 3.770 583 2.1 771 2.880 480 1.7 598 2.290 403 1.4 479 1.7100 342 1.2 396 1.4120 265 0.9 284 1.0The values per plot have been calculated from Schwappach´s figurescorrected for the actual plot size.If the site quality is lower than class I, then there will be more trees perplot at a given age.As can be seen from Table 1, the proposed arrangement will give about8 trees per plot at 1/3 of the rotation age assuming a rotation of 100 years forpine and 120 years for spruce. Thus, as has been discussed above, there willbe enough trees to evaluate the productivity per unit area.At the end of the rotation there will still be one tree per plot and, withthe 8 replicates, 8 trees of the same provenance in the whole experimentalarea. This will be sufficient to compare the provenances in respect of treequality and of numerous other features.Productivity per ha will of course no longer be estimable. However, itwill be possible to corroborate all other characters with those tested earlier,and to establish juvenile-mature correlations.For the reconstruction of the population by means of a seed orchard, 40trees are deemed necessary. These will be available at the age of 40 years inpine (from all the 8 replicates), and at the age of 50 years for spruce. At theseages both the productivity per hectare and most of the other qualities ofinterest will have been reliably compared for the provenances in the experimentand the best ones would have been selected.