Å UMARSKI LIST 1-2/1961

7. H o r v a t I.. Prilog poznavanju nekih fizičkih i mehaničkih svojstava crne johovine,
Š. L. 1960, str. 173—289.
8. Glava č M., Crna joha u Posavskoj i Podravskoj Hrvatskoj s ekološkog, biološkog
i šumsko-uzgojnog gledišta (disertacija — rukopis), Zagreb 1960.
SUMMARY
Taking in account the results of the investigation it is possible to lay out following
conclusions about the rate and the distribution of the reddisch-brown heartwood
in the stem of Black Alder (A. Glutinosa):
1) Diameter of the heartwood increases from the stamp to the top of the stem
till about between 5 and 7 meters above the ground. From this point in the direction
to the top of the stem it decreases.
2) The rate of the heartwood also increases from the stamp to the tree top till
the height of about 9 meters above the ground, where it reaches nearly 84 percent
of the diameter of the stem.
The curve in the fig. no 5, which represents the relation between the height
of the cross-section of the stem and percentage of the heartwood in the diameter
of the stem shows a positive and quite high correlation
r = 0.720 ± 0.0337
3) The width of the sapwood is not constant in the longitudinal direction of the
stem. The widthest sapwood is on the stamp, and decreases till the height of the
9 meters above the ground, where narrowest sapwood has about 1.7 centimeters
(about 3/4 of the inch). From this point to the top of the stem it increases. The
width of the sapwood, in longitudinal direction from the stamp to the top of the
stem, is possible to show with the curve in fig. 5.
The correletion is positive and quite high and is
r = 0.837 ± 0.0205
4) The number of the annual rings of the heartwood in the longitudinal direction
from the stamp to the top of the stem shows quite similar alterations to those of the
diameter of heartwood. It increases till the height of about 7 meters above the
ground, and from this point to the top of the stem it decreases (Sec. table No. 5. and
fig, No. 6).
5) The rate of the number of annual rings of heartwood incresases from the
stamp till the height of the 8 meters above the ground, where it reaches its maximum
(See fig. No. 6).
The correlation is positive and expressed with
r = 0.678 ± 0.0323
6) The number of the annual rings of the sapwood decreases from the stamp
to the height of about 9 meters above the gronud, and the average lowest number
of annual rings of sapwood is tvelwe. From this height to the top it increasses (See
table No. 3 and fig. No. 6).
The correlation between the height of the cross-section of stem above the
ground and the number of the annual rings of sapwood is positiv and is high
r = 0.785 ± 0.0270
7) The area of heariwood on the cross-section of stem increases in the longitudinal
direction from stamp to the top of the stem till about 5 meters above the
ground or to one fith of the height of tree (See fig. No. 7 and table No. 4). From
this height to the top of the stem it decreases and it stops in the height of about
24 meters above the ground.
8) The rate of the heartwood area on the cross-section of stem increases from
the stamp to the height of 9 meters above the ground, where it reaches its highest
value with about 70 percent of the area of the cross-section.
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