atlas of macroscopic wood identi˜ cation
TRANSCRIPT
8
Specimen Preparation
The �rst operation to do when performing an identi�cation is to locate the three planes of observation (transverse, longitu-dinal radial and longitudinal tangential—see Chap. 1) within the specimen and to check that they are perfectly orientated: a surface out of plane is not suitable for identi�cation, since the anatomical characters will appear stretched and deformed.
First of all, determine the grain direction of the specimen: longitudinal and transverse surfaces must be perfectly paral-lel and perpendicular to it, respectively. Once you have located the transverse surface, you can use it to check the longitudinal ones orientation. With a utility knife clean a por-tion of the transverse surface in correspondence to the border of the longitudinal surface you want to check and observe ray direction: the latter surface will be radial or tangential if parallel or perpendicular to ray direction, respectively.
A transverse surface is correctly oriented if perpendicular to the grain, and a longitudinal surface is correctly oriented if parallel to the grain and either parallel or perpendicular to ray direction as seen on the transverse surface.
In order to adjust a specimen surface not correctly ori-ented, a saw or a utility knife is best suited. You will most likely need a saw to amend grossly out-of-plane surfaces or if you want to cut the entire specimen surface. For identi�ca-tion purposes, however, most of the times it is enough to have few square centimetres of correctly oriented surfaces, a result that can be easily obtained by making small cuts with the utility knife (Fig.�2.3).
Once you have correctly oriented surfaces, you can make clean cuts as described in section “Cutting Tools” to obtain perfect characters visibility. Alternatively, you can smooth the surface with abrasive paper (use up to 800 or 1000 grit for best
results); in this case be aware that the wood dust produced by sanding will occlude cell lumina, especially the small ones.
Hand Lens Observation
For macroscopic wood identi�cation we recommend to use a 10× or 14× magni�cation. Hold the lens with one hand as close to your eye as possible, while with the other hand adjust the distance between the lens and the specimen until its surface appears in focus (Fig.�2.4). It is very important to always ensure the best possible illumination of the specimen; therefore always work in a bright environment and be sure not to shade the specimen with the hand holding the hand lens or your head. Also consider that the best illumination is provided by sunlight.
Fig. 2.3 How to obtain correctly oriented surfaces
Fig. 2.4 How to use a hand lens
Fig. 2.2 Cutting procedure with razor blade
9© Springer Nature Switzerland AG 2019F. Ruffinatto, A. Crivellaro, Atlas of Macroscopic Wood Identification, https://doi.org/10.1007/978-3-030-23566-6_3
Materials and Methods
Species Selection
This book includes the timber species listed in the European Standard EN 13556, the CITES-listed timber species (up to 2018) and other selected species relevant in the European timber market.
POWO (2019) has been adopted as reference for scientific names and systematic classification, while EN 13556, Gérard et al. (2017) and Giordano (1988) were used for common names.
Specimen Preparation and Imaging
Small wooden blocks of about 2 cm side length have been cut and the transverse surfaces polished to 1000 grit to obtain the best definition of wood characters. For each species mac-roscopic pictures of cross sections have been taken at 10× magnification. An Olympus SZX10 stereomicroscope fitted with an Olympus KL1500 LCD light source and a ColorView I digital colour camera have been used to collect pictures.
Specimen Description
Wood descriptions have been compiled according to the macroscopic character list by Ruffinatto et al. (2015). Some characters have been modified from the original list in conse-quence of the experience gained by compiling the descrip-tions for this book, in detail characters 20 (definition modified), 42 (one character state added), 43 (two character states modified), 49 (definition modified), 52 (one character state added), 57b (added), 97 (one character state added) and 106 (two character states added). A complete updated list of characters and their definitions is now available in Chap. 4.
Character 2 has not been used since, by definition, it is not apt to distinguish different timbers. Characters related to extractive properties (96, 97, 98, 99, 100, 101) are more reli-ably assessed on a large number of samples because of their variability. For this reason Miller (2007) has been used as
reference for characters 96 and 97, while characters 98–101 have not been included in the absence of a similar reference. Information about the latter characters has been recorded (as additional notes) only if, according to bibliography or authors’ experience, consistent within the species/genus and remarkably helpful for identification. Characters 102 and 103 have been excluded too since quite variable as well (according to authors’ experience).
For each wood species the Atlas provides a complete macroscopic description plus the following data (sources in brackets):
• English, French and German common names1 (EN 13556 2003; Giordano 1988; Gérard et al. 2017)
• IUCN status according to the IUCN red list of threatened species (IUCN 2018)
• Decay resistance according to EN 350 (EN 350 2016; Gérard et al. 2017)
• Resistance to dry wood insect borers according to EN 350 (EN 350 2016; Gérard et al. 2017)
• Resistance to termites according to EN 350 (EN 350 2016; Gérard et al. 2017)
• Treatability according to EN 350 (EN 350 2016; Gérard et al. 2017)
• Use class2 according to EN 335 (Gérard et al. 2017)• Tangential shrinkage (TS), radial shrinkage (RS) and TS/
RS ratio (Cividini 2001; Gérard et al. 2017; Meier 2016)• Modulus of elasticity (MOE) and modulus of rupture
(MOR) (Giordano 1988; Gérard et al. 2017; Meier 2016)• Janka hardness (Global species website 2018; Meier 2016)• Maximum stem diameter at breast height (Giordano 1988;
Gérard et al. 2017; Meier 2016)• Timber most common end uses (Giordano 1988; Gérard
et al. 2017; Meier 2016)
1 Be aware that, as a rule, several common/commercial names apply to a single species.2 Except when otherwise stated, for each class the use in lower classes is admitted too.
3
10
In order to contextualise each timber from a botanical, commercial and identification point of view, several infor-mation about the genus are provided too (data sources in brackets):
• Family name (POWO 2019)• Number of species within the genus (POWO 2019)• CITES-listed species3 within the genus, if any (Species+
2018)• Main timbers of commercial interest within the genus4
• Timbers belonging to other genera but with similar com-mercial names, if any
• Details about to what extent timbers within the genus can be typically5 identified through macroscopic6 and micro-scopic7 analysis, if any
• Worldwide distribution (POWO 2019)
3 CITES restrictions do not apply to plants artificially propagated or that come from commercial plantations.4 For each timber not described within the Atlas, the geographical area of origin is reported in square brackets (codes from Ruffinatto et al. 2015).5 i.e. exlcuding the availability of any supplemental information (e.g. geographical origin), which might improve identification accuracy.6 If not otherwise stated, it is typically not possible to identify single species or group of species within the genus.7 If not otherwise stated, the implied level of accuracy by microscopic identification is the genus.
References
Cividini R (2001) Essicazione convenzionale dei legnami. Compendio. Editore Nardi S.p.a.
EN 13556 (2003) Round and sawn timber. Nomenclature of timbers used in Europe
EN 335 (2013) Durability of wood and wood-based products. Use classes: definitions, application to solid wood and wood-based products
EN 350 (2016) Durability of wood and wood-based products. Testing and classification of the durability to biological agents of wood and wood-based materials
Gérard J, Guibal D, Paradis S, Cerre JC (2017) Tropical timber atlas. Technological characteristics and uses. Éditions Quae
Giordano G (1988) Tecnologia del legno. Volume III: parte seconda. I legnami del commercio. UTET
Global Species Website (2018). http://www.globalspecies.org/. Accessed 2018
IUCN (2018) The IUCN Red list of threatened species. http://www.iucnredlist.org. Accessed 2018
Meier E (2016) Wood! Identifying and using hundreds of woods world-wide. Edited by The Wood Database
Miller RB (2007) Fluorescent woods of the world. In: Flynn JH (ed) A guide to more useful woods of the world. Forest Products Society, Madison, WI, pp 271–305
POWO (2019) Plants of the world online. Facilitated by the Royal Botanic Gardens, Kew. http://www.plantsoftheworldonline.org/. Accessed 2018
Ruffinatto F, Crivellaro A, Wiedenhoeft AC (2015) Review of macro-scopic features for hardwood and softwood identification and a pro-posal for a new character list. IAWA J 36(2):208–241
Species+ (2018). https://www.speciesplus.net/. Accessed 2018
3 Materials and Methods
11© Springer Nature Switzerland AG 2019F. Ruffinatto, A. Crivellaro, Atlas of Macroscopic Wood Identification, https://doi.org/10.1007/978-3-030-23566-6_4
Definition of Macroscopic Characters
In this chapter, each character used for macroscopic wood identification is described along with its character states (in square brackets) and definition (Ruffinatto et al. 2015). Character states represent any possible attribute applicable to a character. The implied surface of observation is the trans-verse one, unless otherwise stated in the character descrip-tion. A summary of all characters is provided in Table 4.1.
Anatomical Characters, Wood with and Without Vessels (Hardwoods and Softwoods)
Growth Rings
1. Growth rings distinct [present/absent/variable] (in Figs. 4.1, 4.2 and 4.3 growth rings are marked by an arrow on the right of the picture)
Growth rings with an abrupt structural change at the boundaries between them (IAWA 1989).Growth ring boundaries can be marked by one or more of the following structural changes: (a) Thick-walled and radially flattened latewood fibres or
tracheids versus thin-walled earlywood fibres or tra-cheids, macroscopically visible as a difference in colour intensity (lighter in earlywood)
(b) Distinct differences in colour between earlywood (light) and latewood (dark) (softwoods and ring- porous hardwoods)
(c) Marked difference in vessel diameter between late-wood and earlywood of the following ring as in ring- and semi-ring-porous woods (hardwoods)
(d) Marginal parenchyma, terminal or initial (hardwoods)
(e) Decreasing frequency of parenchyma bands towards the latewood resulting in distinct fibre zones (hardwoods)
(f) Distended or noded rays (hardwoods) (Richter and Oelker 2002, adapted from IAWA 1989)
2. Growth rings per cm [numerical value/NA]Growth ring width is not used to separate different spe-
cies of wood, but can sometimes be used as an indicator of whether an unknown is from a plantation or a natural stand of trees. Generally speaking, plantation-grown spe-cies grow more rapidly than the same species does in nature, resulting in abnormally wide growth rings (Wiedenhoeft 2011).
General CommentsAlthough plant stems are typically round with some random irregularity, some species have characteristic undulated or indented growth ring boundaries. This is a variable trait in a number of species, but it is consistent enough in some to be useful in identification (e.g. Carpinus spp.). This characteris-tic should be recorded in the notes.
Anatomical Characters, Wood with Vessels (Hardwoods)
Porosity
3. Diffuse-porous [present/absent/variable] (Fig. 4.3)Wood in which the vessels have more or less the same
diameter throughout the growth ring. The vast majority of tropical species and most temperate species show this pattern. In some temperate diffuse-porous woods the lat-est formed vessels in the latewood may be considerably smaller than those of the earlywood of the next ring, but vessel diameter is more or less uniform throughout most of the growth ring (IAWA 1989).
4. Semi-ring porous [present/absent/variable] (Figs. 4.4 and 4.5)
(1) Wood in which the vessels in the earlywood are distinctly larger than those in the latewood of the previ-ous growth ring, but in which there is a gradual change to narrower vessels in the intermediate and latewood of the same growth ring (Fig. 4.4), or (2) wood with a dis-
4
12
Tabl
e 4.
1 L
ist o
f m
acro
scop
ic c
hara
cter
s an
d ch
arac
ter
stat
es
Stru
ctur
ePr
oper
tyC
hara
cter
Cha
ract
er s
tate
sM
acro
scop
ic f
eatu
re
num
ber
Ana
tom
ical
fe
atur
esH
ardw
ood
Gro
wth
rin
gsG
row
th r
ings
Gro
wth
rin
gs d
istin
ctP/
A/V
1
Gro
wth
rin
gs p
er c
entim
etre
Num
eric
al v
alue
/NA
2V
esse
lsPo
rosi
tyD
iffu
se p
orou
sP/
A/V
3Se
mi-
ring
por
ous
P/A
/V4
Rin
g-po
rous
P/A
/V5
Num
ber
of r
ows
of e
arly
woo
d po
res
One
row
/mor
e th
an o
ne r
ow/V
/NA
6
Wid
est t
ange
ntia
l spa
cing
bet
wee
n ea
rlyw
ood
vess
els
One
ear
lyw
ood
vess
el a
t mos
t/mor
e th
an o
ne e
arly
woo
d ve
ssel
7
Arr
ange
men
tV
esse
ls in
tang
entia
l ban
dsP/
A/V
8V
esse
ls in
rad
ial p
atte
rnP/
A/V
9V
esse
ls in
dia
gona
l pat
tern
(e
chel
on)
P/A
/V10
Ves
sels
in d
endr
itic
patte
rn
(flam
e-lik
e)P/
A/V
11
Gro
upin
gsSo
litar
y an
d in
rad
ial m
ultip
les
of
2–3
vess
els
P/A
/V12
Exc
lusi
vely
sol
itary
(90
% o
r m
ore)
P/A
/V13
Rad
ial m
ultip
les
of 4
or
mor
e co
mm
onP/
A/V
14
Clu
ster
s co
mm
onP/
A/V
15Fr
eque
ncy
≤5 v
esse
ls p
er s
quar
e m
illim
etre
P/A
/V16
6–20
ves
sels
per
squ
are
mill
imet
reP/
A/V
17>
20 v
esse
ls p
er s
quar
e m
illim
etre
P/A
/V18
Ves
sel d
iam
eter
/por
e vi
sibi
lity
Smal
l (no
t vis
ible
to th
e na
ked
eye,
le
ss th
an 8
0 μm
)P/
A/V
19
Med
ium
(ju
st v
isib
le to
the
nake
d ey
e, 8
0–13
0 μm
)P/
A/V
20
Lar
ge (
com
mon
ly v
isib
le to
the
nake
d ey
e, la
rger
than
130
μm
)P/
A/V
21
Lat
ewoo
d po
re
visi
bilit
yL
atew
ood
pore
s la
rge,
indi
vidu
ally
di
stin
ct, a
nd f
ew e
noug
h th
at th
ey
can
be r
eadi
ly c
ount
ed
P/A
/V/N
A22
Ves
selle
ss b
ands
Ves
selle
ss ta
ngen
tial b
ands
P/A
23Ty
lose
sTy
lose
s co
mm
on [
TR
, TL
S, R
LS]
P/A
/V24
Ves
sel d
epos
itsG
ums
and
othe
r de
posi
ts in
he
artw
ood
vess
els
[TR
, TL
S, R
LS]
P/A
/V25
Dep
osits
whi
te [
TR
, TL
S, R
LS]
P/A
26D
epos
its y
ello
w [
TR
, TL
S, R
LS]
P/A
27D
epos
its d
ark
[TR
, TL
S, R
LS]
P/A
28
4 Definition of Macroscopic Characters
13
Axi
al
pare
nchy
ma
Dis
trib
utio
nD
iffu
seP/
A/V
29
Dif
fuse
-in-
aggr
egat
esP/
A/V
30V
asic
entr
icP/
A/V
/uni
late
ral
31L
ozen
ge-a
lifor
mP/
A/V
/uni
late
ral
32W
inge
d-al
ifor
mP/
A/V
/uni
late
ral
33C
onflu
ent
P/A
/V/u
nila
tera
l34
Ban
ded
Maj
ority
wid
e/m
ajor
ity n
arro
w/V
/A35
Ban
ded
pare
nchy
ma
dist
ribu
tion
Thr
ough
out t
he r
ing/
in la
tew
ood
only
/in e
arly
woo
d on
ly/N
A36
Pare
nchy
ma
band
s w
ider
than
ray
sP/
A/V
37Pa
renc
hym
a in
mar
gina
l or
seem
ingl
y m
argi
nal b
ands
P/A
/V38
Ret
icul
ate
P/A
/V39
Scal
arif
orm
P/A
/V40
Fest
oone
dP/
A/V
41Pr
edom
inan
t par
ench
yma
patte
rn
with
in th
e bo
dy o
f th
e “g
row
th
ring
”
A/d
iffu
se/d
iffu
se-i
n-ag
greg
ates
/vas
icen
tric
/loze
nge-
alif
orm
/win
ged-
alif
orm
/con
fluen
t/ban
ded/
in m
argi
nal o
r se
emin
gly
mar
gina
l ban
ds/r
etic
ulat
e/sc
alar
ifor
m/
fest
oone
d
42
Ray
sW
idth
Ray
vis
ibili
ty to
the
nake
d ey
e on
th
e tr
ansv
erse
sec
tion
Ray
s no
t vis
ible
/ray
s vi
sibl
e/so
me
of th
e ra
ys c
lear
ly
mor
e ev
iden
t tha
n th
e ot
hers
43
Ray
vis
ibili
ty w
ith th
e na
ked
eye
on th
e ta
ngen
tial s
urfa
ce [
TL
S]R
ays
not v
isib
le/r
ays
visi
ble
44
Rat
io o
f ra
y w
idth
to p
ore
diam
eter
Lar
ger
rays
nar
row
er th
an w
ider
por
es/la
rger
ray
s as
w
ide
or w
ider
than
wid
er p
ores
45
Nod
ed r
ays
P/A
/V46
Stor
ying
Ray
sto
ryin
g [T
LS]
Not
sto
ried
(ab
sent
)/re
gula
r co
arse
sto
ryin
g/re
gula
r fin
e st
oryi
ng/ir
regu
lar
coar
se s
tory
ing/
irre
gula
r fin
e st
oryi
ng47
Hei
ght
Ray
hei
ght [
TL
S]H
ighe
st r
ays
less
than
5 m
m h
igh/
high
est r
ays
mor
e th
an
5 m
m h
igh
48
Ray
s pe
r m
illim
etre
Ray
s pe
r m
illim
etre
≤4/m
m/5
–12/
mm
/>12
/mm
/NA
49W
ood
rayl
ess
50Fi
bres
Arr
ange
men
tFi
bres
in r
adia
l arr
ange
men
tP/
A51
Can
als
Inte
rcel
lula
r ca
nals
Axi
al c
anal
sA
/dif
fuse
/in s
hort
tang
entia
l lin
es/in
long
tang
entia
l lin
es/V
52
Tra
umat
ic c
anal
sP
53R
adia
l can
als
P/A
54Ph
loem
Phlo
emIn
clud
ed p
hloe
mA
/dif
fuse
/con
cent
ric
55So
ftw
ood
Gro
wth
rin
gsE
arly
woo
d/la
tew
ood
tran
sitio
nE
arly
woo
d/la
tew
ood
tran
sitio
nA
brup
t tra
nsiti
on f
rom
ear
lyw
ood
to la
tew
ood/
grad
ual
tran
sitio
n fr
om e
arly
woo
d to
late
woo
d/V
56
Axi
al c
anal
sA
xial
can
als
Axi
al c
anal
sL
arge
/sm
all/A
57T
raum
atic
can
als
P57
b
Anatomical Characters, Wood with Vessels (Hardwoods)
14
Tabl
e 4.
1 (c
ontin
ued)
Axi
al
pare
nchy
ma
Vis
ibili
tyA
xial
par
ench
yma
visi
ble
with
ha
nd le
nsSc
arce
dif
fuse
/tang
entia
lly z
onat
e/A
58
Non
an
atom
ical
fe
atur
es
Har
dwoo
d +
So
ftw
ood
Hea
rtw
ood
Col
our
Hea
rtw
ood
colo
ur d
arke
r th
an
sapw
ood
colo
urP/
A59
Hea
rtw
ood
basi
cally
bro
wn
or
shad
es o
f br
own
P/A
60
Hea
rtw
ood
basi
cally
red
or
shad
es
of r
edP/
A61
Hea
rtw
ood
basi
cally
yel
low
or
shad
es o
f ye
llow
P/A
62
Hea
rtw
ood
basi
cally
whi
te to
gre
yP/
A63
Hea
rtw
ood
with
str
eaks
P/A
64D
ensi
tyD
ensi
tyD
ensi
ty lo
w: <
0.40
g/c
m3 /
dens
ity m
ediu
m: 0
.40–
0.75
g/
cm3 /
dens
ity h
igh:
>0.
75 g
/cm
3
65
Odo
urO
dour
A/d
istin
ctly
pre
sent
and
ple
asan
t (sw
eet,
spic
y, fl
oral
)/di
stin
ctly
pre
sent
and
unp
leas
ant (
sour
, bitt
er, f
oetid
)66
Oily
sur
face
Oily
sur
face
P/A
67H
abit
Tre
eP/
A/V
68Sh
rub
P/A
/V69
Vin
e/lia
na/c
limbe
rP/
A/V
70G
eogr
aphi
cal
dist
ribu
tion
Eur
ope
and
tem
pera
te A
sia
(Bra
zier
an
d Fr
ankl
in r
egio
n 74
)P/
A71
Eur
ope,
exc
ludi
ng M
edite
rran
ean
P/A
72M
edite
rran
ean
incl
udin
g N
orth
ern
Afr
ica
and
the
Mid
dle
Eas
tP/
A73
Tem
pera
te A
sia
(Chi
na),
Jap
an,
USS
RP/
A74
Cen
tral
Sou
th A
sia
(Bra
zier
and
Fr
ankl
in r
egio
n 75
)P/
A75
Indi
a, P
akis
tan,
Sri
Lan
kaP/
A76
Bur
ma
P/A
77So
uthe
ast A
sia
and
the
Paci
fic
(Bra
zier
and
Fra
nklin
reg
ion
76)
P/A
78
Tha
iland
, Lao
s, V
ietn
am,
Cam
bodi
a (I
ndoc
hina
)P/
A79
Indo
mal
esia
: Ind
ones
ia, t
he
Phili
ppin
es, M
alay
sia,
Bru
nei,
Sing
apor
e, P
apua
New
Gui
nea
and
Solo
mon
Isl
ands
P/A
80
Paci
fic I
slan
ds (
incl
udin
g N
ew
Cal
edon
ia, S
amoa
, Haw
aii a
nd F
iji)
P/A
81
Stru
ctur
ePr
oper
tyC
hara
cter
Cha
ract
er s
tate
sM
acro
scop
ic f
eatu
re
num
ber
4 Definition of Macroscopic Characters
15
Aus
tral
ia a
nd N
ew Z
eala
nd
(Bra
zier
and
Fra
nklin
reg
ion
77)
P/A
82
Aus
tral
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Anatomical Characters, Wood with Vessels (Hardwoods)
16
tinct ring of closely spaced earlywood vessels that are not markedly larger than the latewood vessels of the pre-ceding ring or the same growth ring (Fig. 4.5) (IAWA 1989).
5. Ring-porous [present/absent/variable] (Figs. 4.6 and 4.7)
The vessels in the earlywood are distinctly larger than those in the latewood of the previous growth ring and of the same growth ring, and form a well-defined zone or ring, and there is an abrupt transition to the latewood of the same growth ring (IAWA 1989).
6. Number of rows of earlywood pores [one row/more than one row/variable/NA] (Figs. 4.6 and 4.7)
How many vessels wide the earlywood ring of a ring-porous wood is. Such characteristics can be useful in dis-tinguishing between species (IAWA 1989).
7. Widest tangential spacing between earlywood vessels [one earlywood vessel at most/more than one earlywood vessel] (Figs. 4.6 and 4.7)
The earlywood of some ring-porous woods exhibits characteristic spacing between earlywood vessels. In many woods spaces are less than the diameter of one
Fig. 4.2 Cross section (10×) of Pinus sylvestris. 1—Growth rings dis-tinct [present]. 56—Earlywood/latewood transition [abrupt transition from earlywood to latewood]. 57—Axial canals [large]
Fig. 4.3 Cross section (10×) of Ilex aquifolium. 1—Growth rings dis-tinct [present]. 3—Diffuse-porous [present]. 9—Vessels in radial pat-tern [present]. 14—Vessels in radial multiples of four or more common [present]. 18—>20 vessels per square millimetre [present]. 19—Vessels small (not visible to the naked eye, less than 80 μm) [present]
Fig. 4.4 Cross section (10×) of Juglans regia. 4—Semi- ring porous [present]. 12—Vessels solitary and in radial multiples of 2–3 vessels [present]. 17—6–20 vessels per square millimetre [present]. 20—Vessels medium (just visible to the naked eye, 80–130 μm) [present]
Fig. 4.1 Cross section (10×) of Taxodium distichum. 1—Growth rings distinct [present]. 56—Earlywood/latewood transition [gradual transi-tion from earlywood to latewood]. 58—Axial parenchyma visible with hand lens [tangentially zonate]
4 Definition of Macroscopic Characters
17
earlywood vessel, whereas in others the distance between earlywood vessels is sometimes greater than two or more earlywood vessel diameters (Ruffinatto et al. 2015, Wheeler et al. 1989).
General CommentsCaution: Slow-grown ring-porous woods have narrow growth rings with very little latewood. Be careful not to con-fuse the closely spaced earlywood zones of slow-grown ring-
porous woods with a tangential pattern, or to interpret such woods as diffuse-porous (IAWA 1989).
Vessel Arrangement
8. Vessels in tangential bands [present/absent/variable] (Fig. 4.7)Vessels arranged perpendicular to the rays and forming short or long tangential bands; these bands can be straight or wavy (IAWA 1989).
9. Vessels in radial pattern [present/absent/variable] (Fig. 4.3)Vessels are arranged radially independently from their grouping (adapted from IAWA 1989).
10. Vessels in diagonal pattern (echelon) [present/absent/variable] (Fig. 4.8)Vessels are arranged intermediate between tangential and radial (IAWA 1989).
11. Vessels in dendritic pattern (flame-like) [present/absent/variable] (Fig. 4.6)Vessels are arranged in a branching pattern, forming distinct tracts, separated by areas devoid of vessels (IAWA 1989).
General CommentsThese features often occur in combination. All applicable features should be recorded. When rings are narrow these patterns are not obvious. In ring-porous woods, only the intermediate wood and latewood are examined for vessel arrangement description (IAWA 1989).
Fig. 4.5 Cross section (10×) of Prunus avium. 4—Semi- ring porous [present]. 12—Vessels solitary and in radial multiples of 2–3 vessels [present]. 18—>20 vessels per square millimetre [present]. 19—Vessels small (not visible to the naked eye, less than 80 μm) [present]. 49—Rays per millimetre [5–12/mm]
Fig. 4.6 Cross section (10×) of Quercus rubra. 5—Ring- porous [pres-ent]. 6—Number of rows of earlywood pores [more than one row]. 7—Widest tangential spacing between earlywood vessels [one earlywood vessel at most]. 11—Vessels in dendritic pattern (flame-like) [present]. 22—Latewood pores large, individually distinct and few enough that they can be readily counted [present]. 35—Axial parenchyma banded [majority narrow]. 36—Banded parenchyma distribution [in latewood only]
Fig. 4.7 Cross section (10×) of Ulmus glabra. 5—Ring- porous [pres-ent]. 6—Number of rows of earlywood pores [more than one row]. 7—Widest tangential spacing between earlywood vessels [one earlywood vessel at most]. 8—Vessels in tangential bands [present]. 15—Vessel clusters common [present]. 23—Vesselless tangential bands [present]
Anatomical Characters, Wood with Vessels (Hardwoods)
18
“No specific pattern” is a term of convenience; the major-ity of hardwoods do not feature a specific vessel arrangement (Richter and Oelker 2002).
Vessel Groupings
12. Vessels solitary and in radial multiples of 2–3 vessels [present/absent/variable] (Figs. 4.4 and 4.5)
Variable proportions of the vessels solitary (less than 90%) and in relatively short radial multiples of 2–3(−4) vessels. This is the most common character state for ves-sel grouping in hardwoods.
13. Vessels exclusively solitary (90% or more) [present/absent/variable] (Figs. 4.8 and 4.9)
90% or more of the vessels are completely sur-rounded by other cells than vessels; that is, 90% or more appear not to contact another vessel (IAWA 1989).
14. Vessels in radial multiples of four or more common [present/absent/variable] (Fig. 4.3)
Radial files of four or more adjacent vessels of com-mon occurrence (IAWA 1989).
15. Vessel clusters common [present/absent/variable] (Figs. 4.7 and 4.10)
Groups of three or more vessels having both radial and tangential contacts, and of common occurrence (IAWA 1989).
General CommentsFeatures 14 and 15 should be used only when they are of common occurrence. Clusters and radial multiples are not
mutually exclusive and can occur in combination (adapted from IAWA 1989).
Vessel Frequency
16. ≤5 vessels per square millimetre [present/absent/vari-able] (Fig. 4.11)
17. 6–20 vessels per square millimetre [present/absent/vari-able] (Figs. 4.4 and 4.8)
18. >20 vessels per square millimetre [present/absent/vari-able] (Figs. 4.3 and 4.5)
Fig. 4.8 Cross section (10×) of Eucalyptus camaldulensis. 10—Vessels in diagonal pattern (echelon) [present]. 13—Vessels exclu-sively solitary (90% or more) [present]. 17—6–20 vessels per square millimetre [present]. 24—Tyloses common [present]. 31—Axial paren-chyma vasicentric [present]. 49—Rays per millimetre [>12/mm]
Fig. 4.9 Cross section (10×) of Dryobalanops lanceolata. 13—Vessels exclusively solitary (90% or more) [present]. 52—Axial canals [in long tangential lines]
Fig. 4.10 Cross section (10×) of Grevillea robusta. 15—Vessel clus-ters common [present]. 40—Axial parenchyma scalariform [present]. 41—Axial parenchyma festooned [present]. 43—Ray visibility to the naked eye on the transverse surface [some of the rays clearly more evi-dent than the others]
4 Definition of Macroscopic Characters
19
General CommentsAll vessels are counted as individuals; for example, a radial multiple of four would be counted as four vessels. Vessel frequency is not computed for ring-porous woods (IAWA 1989).
In practice this number is determined by counting vessels within a given area and then dividing by the amount needed to have the /sq. mm number (adapted from Ilic 1990).
There are no further classes after the “20 vessels per square millimetre” because such woods have vessels too small to count accurately with a hand lens. The number of vessels per square millimetre can be more easily determined with the aid of a transparent reference grid.
Vessel Diameter/Pore Visibility
19. Vessels small (not visible to the naked eye, less than 80 μm) [present/absent/variable] (Figs. 4.3 and 4.5)
20. Vessels medium (just visible to the naked eye, 80–130 μm) [present/absent/variable] (Fig. 4.4)
21. Vessels large (commonly visible to the naked eye, larger than 130 μm) [present/absent/variable] (Figs. 4.11 and 4.12)
General CommentsLarge vessel lumen is clearly visible to the naked eye with-out the aid of a loupe, whereas in medium vessels it is per-ceivable but not clearly discernable. Pore visibility at the naked eye is determined not only by vessels dimension, but by their contrast with the background tissue too. For this rea-son, consider the vessels diameter range given by the defini-
tions as indicative, since vessels of the same dimension may fall in different categories depending on the species.
Latewood Pore Visibility
22. Latewood pores large, individually distinct and few enough that they can be readily counted [present/absent/variable/NA] (Fig. 4.6)
This feature applies only to ring-porous woods. All the latewood pores must be distinct and countable. This is contrasted with latewood pores which are numerous and indistinct, where they are impossible to see and count indi-vidually. This feature is used, for instance, for the separa-tion of the red oak group (feature present) from the white oak one (feature absent) (adapted from Hoadley 1990).
Vesselless Bands
23. Vesselless tangential bands [present/absent] (Fig. 4.7)Long more or less continuous tangential zones within
the growth ring without vessels, the radial extent of which is at least two times the tangential vessel diameter of the vessels in the adjacent portions of the growth ring.
Tyloses
24. Tyloses common [present/absent/variable] (Fig. 4.8)Tyloses are best recognised on account of strong light
reflection from the numerous facets producing a dis-tinctive glitter (much like the iridescent glitter of soap
Fig. 4.11 Cross section (10×) of Amburana cearensis. 16—≤5 ves-sels per square millimetre [present]. 21—Vessels large (commonly visible to the naked eye, larger than 130 μm) [present]. 25—Gums and other deposits in heartwood vessels [present]. 32—Axial parenchyma lozenge-aliform [present]. 34—Axial parenchyma confluent [present]
Fig. 4.12 Cross section (10×) of Dipterocarpus alatus. 21—Vessels large (commonly visible to the naked eye, larger than 130 μm) [pres-ent]. 25—Gums and other deposits in heartwood vessels [present]. 29—Axial parenchyma diffuse [present]. 31—Axial parenchyma vasi-centric [present]. 52—Axial canals [in short tangential lines]
Anatomical Characters, Wood with Vessels (Hardwoods)
20
bubbles). Likewise, tyloses can be observed on longi-tudinal surfaces filling the vessel lines. Tyloses may be few or many, ranging from all vessels filled with many tyloses to a few vessels with a few tyloses. This feature applies only when tyloses are not of sporadic occurrence (Richter and Oelker 2002).
In some taxa, tyloses are also characteristically small and densely packed (e.g. Robinia pseudoacacia), of typ-ical size and appearance (Quercus alba) or with a char-acteristic multicoloured reflective pattern (e.g. Fraxinus americana). These characteristics can be recorded in a comments section in a description.
Vessel Deposits
25. Gums and other deposits in heartwood vessels [present/absent/variable] (Figs. 4.11 and 4.12)
26. Deposits white [present/absent] 27. Deposits yellow [present/absent] 28. Deposits dark [present/absent]
General Comments“Gums and other deposits” includes a wide variety of chemi-cal compounds, which are variously coloured (white, yellow, red, brown, black) (IAWA 1989).
In dark-coloured woods, some deposits are seen as chalky streaks on longitudinal surfaces (Ilic 1990).
Axial Parenchyma Distribution
29. Axial parenchyma diffuse [present/absent/variable] (Fig. 4.12)
Diffuse parenchyma appears as small dots of gener-ally lighter coloured cells scattered among the fibres (Wiedenhoeft 2011).
Diffuse parenchyma may be very difficult to see with a hand lens when devoid of cell contents and of equal wall thickness as the surrounding fibres, but is more eas-ily seen when the cells are crystalliferous or the fibres are thick walled, or both.
30. Axial parenchyma diffuse-in-aggregates [present/absent/variable] (Fig. 4.13)
Parenchyma appears as short discontinuous tangen-tial lines of generally lighter coloured cells scattered among the fibres (Wiedenhoeft 2011).
31. Axial parenchyma vasicentric [present/absent/variable/unilateral] (Figs. 4.8 and 4.12)
Lighter coloured cells appear as a halo or sheath around a solitary vessel or multiple vessels (adapted from Wiedenhoeft 2011).
32. Axial parenchyma lozenge-aliform [present/absent/vari-able/unilateral] (Fig. 4.11)
Lighter coloured cells appear as a halo or sheath with lateral (tangential) extensions forming a diamond- shaped outline (adapted from IAWA 1989).
33. Axial parenchyma winged-aliform [present/absent/vari-able/unilateral] (Fig. 4.14)
Lighter coloured cells appear as a halo or sheath with elongated and narrow lateral (tangential) extensions (adapted from IAWA 1989).
34. Axial parenchyma confluent [present/absent/variable/unilateral] (Fig. 4.11)
Coalescing vasicentric or aliform parenchyma con-nects two or more vessels (adapted from IAWA 1989).
Fig. 4.13 Cross section (10×) of Nauclea diderrichii. 30—Axial parenchyma diffuse-in-aggregates [present]. 45—Ratio of ray width to pore diameter [larger rays narrower than wider pores]
Fig. 4.14 Cross section (10×) of Gonystylus bancanus. 33—Axial parenchyma winged-aliform [present]. 51—Fibres in radial arrange-ment [present]
4 Definition of Macroscopic Characters
21
35. Axial parenchyma banded [majority wide/majority nar-row/variable/absent] (Figs. 4.6, 4.15 and 4.16)
Continuous tangential lines, variable in terms of straightness, width and frequency, and with regard to specific patterns formed with the rays running perpen-dicular to the bands. This feature should be coded only when parenchyma bands constitute a distinct character-istic of the transverse section. Parenchyma bands may be mainly independent of the vessels (apotracheal), defi-nitely associated with the vessels (paratracheal) or both. Bands may be wavy, straight, continuous or discontinu-ous (the latter often intergrading with confluent). Prominent bands will cause, like all concentric struc-
tures, V-shaped or U-shaped markings on tangential faces, with a more or less regular (straight bands) or rather jagged (undulating bands) course. Parenchyma in narrow bands is usually not or only barely visible to the unaided eye. Parenchyma wide bands are usually visible to the unaided eye (Richter and Oelker 2002).
36. Banded parenchyma distribution [throughout the ring/in latewood only/in earlywood only/NA] (Figs. 4.6, 4.15 and 4.16)
Banded parenchyma present through the entire growth ring, only within the latewood or only within the earlywood. This character can be interpreted across the entire early or late portion of the growth ring or can be restricted. For example, pecan and true hickory (both Carya spp.) can be separated by the absence of bands between the earlywood vessels in the latter (adapted from Hoadley 1990, based on Taras and Kukachka 1970).
37. Parenchyma bands wider than rays [present/absent/ variable] (Fig. 4.16)
The radial extent of tangential parenchyma bands as compared to the apparent average ray width. In those woods with two-sized rays (e.g. Grevillea robusta), the comparison is between the parenchyma bands and the wider rays.
38. Axial parenchyma in marginal or seemingly marginal bands [present/absent/variable] (Fig. 4.17)
Parenchyma bands forming a more or less continuous layer of variable width at, or appearing to be at, the mar-gins of a growth ring. With a hand lens, and without developmental study, marginal parenchyma formed at the beginning (initial) or the end (terminal) of the growth season cannot be distinguished. Axial parenchyma
Fig. 4.15 Cross section (10×) of Bombax buonopozense. 35—Axial parenchyma banded [majority narrow]. 36—Banded parenchyma dis-tribution [throughout the ring]. 49—Rays per millimetre [≤4/mm]
Fig. 4.16 Cross section (10×) of Lophira alata. 35—Axial paren-chyma banded [majority wide]. 36—Banded parenchyma distribution [throughout the ring]. 37—Parenchyma bands wider than rays [pres-ent]. 39—Axial parenchyma reticulate [present]
Fig. 4.17 Cross section (10×) of Daniellia ogea. 38—Axial paren-chyma in marginal or seemingly marginal bands [present]. 43—Ray visibility to the naked eye on the transverse surface [rays visible] 52—Axial canals [diffuse]
Anatomical Characters, Wood with Vessels (Hardwoods)
22
bands which are not marginal are typically more fre-quent and more closely spaced (also found between marginal bands), and often follow a more irregular course (wavy, interrupted) than marginal bands (adapted from Richter and Oelker 2002).
39. Axial parenchyma reticulate [present/absent/variable] (Fig. 4.16)
Parenchyma in continuous tangential lines of approxi-mately the same width as the rays, regularly spaced and forming a network with them. The distance between the rays is approximately equal to lower the distance between the parenchyma bands (adapted from IAWA 1989).
40. Axial parenchyma scalariform [present/absent/vari-able] (Fig. 4.10)
Parenchyma in fairly regularly spaced tangential lines or bands, appreciably more closely spaced than the rays and with them producing a ladder-like appearance in cross section. The distance between the rays is greater than the distance between parenchyma bands (adapted from IAWA 1989).
41. Axial parenchyma festooned [present/absent/variable] (Fig. 4.10)
Parenchyma in fairly regularly spaced lines or bands arranged in arcs perpendicular to rays.
42. Predominant parenchyma pattern [absent/diffuse/dif-fuse-in-aggregates/vasicentric/lozenge-aliform/winged-aliform/confluent/banded/in marginal or seemingly marginal bands/reticulate/scalariform/festooned]
While most woods will exhibit several different parenchyma types that can and should be coded sepa-rately, with hand lens observation there is often a pre-dominant apparent parenchyma pattern that best describes the overall axial parenchyma pattern. This can be a useful sorting tool to avoid character redundancy.
General CommentsAxial parenchyma is often recognised by its lighter colour (thin-walled cells with high light reflectivity) and the result-ing colour contrast with the surrounding darker ground tissue (fibres with thicker cell walls). Axial parenchyma is present in nearly all hardwoods, but can be so sparingly developed that it is not visible, even with a hand lens. On longitudinal surfaces, well-developed vasicentric and aliform axial paren-chyma is often visible as a lighter coloured lining of the ves-sel lines. The various types of axial parenchyma often co-occur and/or intergrade within a given taxon (Richter and Oelker 2002).
Unilateral parenchyma forms semicircular hoods or caps only on one side of the vessels, which can extend tangen-tially or obliquely in an aliform or confluent or banded pat-tern, and is used in this list as a modifier for each of the parenchyma types (IAWA 1989).
Macroscopically, vasicentric tracheids and vascular tra-cheids have more or less the same appearance as axial parenchyma and as such are not treated as separate charac-ters in this list. Only by reference to the microscopic anat-omy can the true nature of those cells be known.
Ray Width
43. Ray visibility to the naked eye on the transverse sur-face [rays not visible/rays visible/some of the rays clearly more evident than the others] (Figs. 4.10, 4.17, 4.18)
On transverse surfaces, rays appear as more or less straight lines running perpendicular to the growth rings (Wiedenhoeft 2011).
44. Ray visibility to the naked eye on the tangential surface [rays not visible/rays visible] (Figs. 4.19 and 4.20)
On tangential surfaces, rays appear like small axially oriented lines, usually darker than the background (Wiedenhoeft 2011).
45. Ratio of ray width to pore diameter [larger rays nar-rower than wider pores/larger rays as wide or wider than wider pores] (Figs. 4.13 and 4.18)Ray width estimated by comparison with the tangential diameter of largest pores (Ilic 1990).
46. Noded rays [present/absent/variable] (Fig. 4.18)In some woods, rays appear to flare or become swol-
len as they cross the growth-ring boundary; this can be useful in identification and also indicates distinct growth rings (Hoadley 1990).
Fig. 4.18 Cross section (10×) of Fagus sylvatica. 43—Ray visibility to the naked eye on the transverse surface [some of the rays clearly more evident than the others]. 45—Ratio of ray width to pore diameter [larger rays as wide or wider than wider pores]. 46—Noded rays [present]
4 Definition of Macroscopic Characters
23
General CommentsWhen rays are broad, about 0.5 mm or more in width, they are easily visible with the unaided eye both on the transverse and on the tangential surface (adapted from Richter and Oelker 2002). Character state “some of the rays clearly more evident than the others” mainly applies when broad rays are mixed with not visible ones.
Rays visibility at the naked eye is determined not only by rays width, but by their colour contrast with the back-ground tissue too. For this reason, rays of the same width may be visible or not to the naked eye depending on the species.
On the transverse surface even uniseriate rays will be detectable with a hand lens.
Ray Storying
47. Ray storying [not storied (absent)/regular coarse story-ing/regular fine storying/irregular coarse storying/irreg-ular fine storying] (Fig. 4.21)
Rays arranged in tiers (horizontal series) as viewed on the tangential surface. Tiers of rays are visible with the unaided eye or a hand lens, and appear as fine hori-zontal striations or ripple marks on the tangential sur-face. These series can be described as horizontal/straight (regular storying), or wavy/oblique/only locally present (irregular storying) (adapted from IAWA 1989).
Coarse storying is characterised by three rows or less per axial millimetre, and fine storying by more than four rows per axial millimetre (adapted from CITES 2002).
Ray Height
48. Ray height [highest rays less than 5 mm high/highest rays more than 5 mm high] (Figs. 4.19 and 4.20)
Determine the total ray height on the tangential sur-face, in the axial direction (IAWA 1989).
Rays per Millimetre
49. Rays per millimetre [≤4/mm/5–12/mm/>12/mm/NA] (Figs. 4.5, 4.8 and 4.15)
The number of rays per millimetre determined mac-roscopically on the transverse section. It can be easily established with the aid of a transparent reference grid.
Fig. 4.19 Tangential surface of Fagus sylvatica. 44—Ray visibility to the naked eye on the tangential surface [rays visible]. 48—Ray height [highest rays less than 5 mm high]
Fig. 4.20 Tangential surface of Quercus petraea. 44—Ray visibility to the naked eye on the tangential surface [rays visible]. 48—Ray height [highest rays more than 5 mm high]
Fig. 4.21 Tangential surface of Diospyros kaki. 47—Ray storying [regular coarse storying]
Anatomical Characters, Wood with Vessels (Hardwoods)
24
Wood Rayless
50. Wood raylessWood with axial elements only. Rayless woods are
restricted to a small number of families. Some examples are Arthrocnemum macrostachyum (Chenopodiaceae), Heimerliodendron brunonianum (Nyctaginaceae), Hebe salicifolia and Veronica traversii (Scrophulariaceae) (IAWA 1989).
Fibres
51. Fibres in radial arrangement [present/absent] (Fig. 4.14)Fibres aligned in straight radial rows, typically most evi-dent in fibres with rectangular outlines and large lumina.
Intercellular Canals
52. Axial canals [absent/diffuse/in short tangential lines/in long tangential lines/variable] (Figs. 4.9, 4.12 and 4.17)
Diffuse: randomly distributed solitary canals; in short tangential lines: two to five axial canals in a tangential line; in long tangential lines: more than five canals in a line (IAWA 1989).
Axial canals can be very similar to pores on the end grain surface. They are often distinguished from pores only by means of a special arrangement, e.g. in continu-ous tangential bands, by consistent differences in diam-eter or by exuding resin. The irregular outline of axial canals due to the lack of a single bounding cell wall may also be of some help in distinguishing them from vessels of similar size. In woods with a diffuse distribution of canals, and with a diameter similar to that of the vessels, they can be easily overlooked unless betrayed by exud-ing resin (adapted from Richter and Oelker 2002).
53. Traumatic canals [present] (Fig. 4.22)Timbers which do not have normal resin canals may
still form so-called traumatic resin canals or gum ducts. Traumatic canals form as a response to injury and there-fore may not occur consistently in a given taxon; this is why their absence is not of diagnostic value. Traumatic resin canals usually differ from normal canals, by their large size, irregular outline and/or clustering into short to extremely long tangential groups (adapted from Richter and Oelker 2002).
54. Radial canals [present/absent] (Fig. 4.23)Rays in which radial canals occur are generally spo-
radic, and require special care in observation. Radial canals can be sparse and small with colourless contents or large, abundant, and with coloured contents, or any combination of these. Exudation of resin, gums or latex
by the canals can greatly improve the ease of observa-tion (adapted from Ilic 1990).
On the transverse surface, radial canals appear as apparently wider, broken or distended radial cavities, somewhat similar in appearance to vessel lines on the radial or tangential surfaces.
Included Phloem
55. Included phloem [absent/diffuse/concentric] (Fig. 4.24)Included phloem may have an appearance similar to
axial parenchyma and can be irregularly organised in concentric (tangential bands) or diffuse (scattered and isolated) patterns. Concentric-included phloem very often intergrades with diffuse-included phloem. In spe-
Fig. 4.22 Cross section (10×) of Lovoa trichilioides. 53—Traumatic canals [present]
Fig. 4.23 Cross section (10×) of Mammea africana. 54—Radial canals [present]
4 Definition of Macroscopic Characters