Virginia gazette. [volume] (Williamsburg, Va.) 1893-192?, 1897-11-27


II you want to know how old the
venerable oak on your lawn Is you
,aa easily find out. but You wiii nrst
nave to cut II down and get cross
section as near the base as possible.
Perhaps your curiosity would not jus-
tify such sacFilegious use OF the
woodlands axe. yet Il may be none the
Tess interesting to learn that accord
ing to Mr.. II. +. Fernow. chief OF the
Forestry Division OF the Agricultural
Department at Washington. the cat
culation OF timber tree ages in the
temperate part OF the United States
has been reduced TO science. and its
accuracy has been tested by thousands
Of experiments.
In the trees referred TO the wood OF
/ the stem is laid on in sheets or lay
! ers which on a cross section appear
/ as so many concentric rings. one being
formed each growing season. The
rings appear as alternate narrow
bands Of lighter or darker color, the
dark line. or summer wood" occupy
ing the outer portion OF one ring and
/ being sharply contrasted against tie
/ highest portion OF the inner. higher or
spring wood" part OF the next ring-
These annual rings differ in width.
commonly averaging from one-eightf
OF an inch 20 three-eighths In harc
woods and from, one-tWentieth 10 one
cnghth IL conifers. and cases are not
rare where whole century's growth
OF a spruce or baisam amounts 20 bu,
10 or three inches on the radius OF
the stem IA all young. sound and
thrifty trees. Mr. Fernow says. the
rings are laid on with the utmest reg
ularity and q cross section n a'Stem
furnishes not only Information "A "a
the age OF the grown section. but Is
a fair indication OF the life history OF
the tree. periods 81 suppression and
thrift being indicated respectively by
zones OF corrcsp0ndinsly narrow on
broad rings. In such timber tbs
countings along different radii Away
give the same result.
In very old. slow grown trees dig
ference may appear ~ from one 20 NJ
e. rings. which IL not due 10 the inabiiN.
2 q the eve 10 detect an extremely mar
/ row ring. Is based On tho actual alb
sence of the ring or rings. along
. given radius. unfavorahle circum
stances having led TO failure OF thci
& regular. continuous development.
Il similar irregularity has been observe
r in densoly shaded or otherwise stunte
:. timber. AID also in timber injured b
/. coal smoke. so that given ring. q
d years growth. was found develope
e twenty feet from the ground. but ei
q tircly absent near the stump q 81
same stem
Z To determine the age or tree Il
/. desirable 20 make a clean. smooth ca
3 Frequently a marnifying glass viii
"a found indispensable. Count along u
= greatest radius. avoiding cover'
b. wounds and other obstacles. Since
.h / eeedling OF white pine for instance,
only one foot high when Eve yea
" old. says Mr. Fernow and since q
&c parts OF this hve-year-old Seeding a
- never raised upward by growth, 4
/ growth being by the addition Of nj
"a parts. a cross section TWO and hi
feet from the ground does not inclu
~ this five-year-old tree a. all. So. II I
er number OF rings on the stump secti
= is 100. the real age OF the tree Is I
100 years. but 100 Plus about six. +
En- most purposes il Is sufficiently ne
IS the truth 10 make this allowance. I
r- when greater accuracy is desired. ;
mt cut must be made level with
be ground. so as 10 include the seedl.
nd stem as well.