Midterms Flashcards
What is the most common way of identifying physical and chemical properties of wood?
Microscopic observation (Abe, 2016)
refers to the determination of a
certain wood sample as being
similar to an already known
kind.
Wood Identification
It is also the
determination of the taxonomic
position of wood.
Wood Identification
3 Confirmatory test for identification
a) Splinter/ Ash Tests
b) Fluorescence Tests
c) Froth Tests
Gross physical features of wood
Texture
Color
Taste
Grain Direction
Luster
Weight
Odor
refers to the size and proportional
amount of woody elements.
TEXTURE
due to the presence of extractives
deposited in the wood cells.
COLOR
Colors of wood
Bright yellow or orange
Light wine red to blood red
Black with black stripes
Bright yellow (fresh)
the ability to reflect light.
Luster
Taste of pagatpat and batino
Pagatpat- Salty
Batino- Bitter
resistance to indentation. This may be
known by cutting the sample with a knife or by
applying pressure with the fingernails on the
longitudinal surface of the wood
Hardness
dependent on three factors:
(1) amount of wood substances
(2) moisture content
(3) amount of extractives present
Weight
hardest and heaviest wood in the world found in the Philippines
Mangkono
Malabayabas and Mangkono of Family __________ are
extremely heavy woods
Myrtaceae
this refers to the arrangement
or orientation of the wood elements with
respect to respect to the longitudinal axis
Grain direction
Types of grain direction
Straight grained
Wavy
Cross
Spiral
tangential surface of wood shows the ___________
Grain direction
Lighter colored rings
developed during the rainy
season.
Early wood / spring wood
Cells with thinner
walls and of lower density.
Early wood / spring wood
Darker colored bands
formed during the dry
season.
Late wood or
summerwood
Cells with
thicker walls and of
higher density.
Late wood or
summerwood
A type of growth ring that is sometimes
encountered especially in old or suppressed trees.
Discontinuous ring
formed when factors such as
drought, insect infestation, late frost in
temperate countries affects the structural
development of the cells, and results in a
subsequent formation of more than one ring
during a growing season.
False ring
One false ring included in the true
ring
Double ring
More than 1 false ring is included
* Results in overestimation of the age of the tree.
Multiple ring
Growth increments are ________ near the lower
part of the crown and ___________ in width toward
both the tip and the base of the trunk
(lengthwise).
Widest, Decrease
Factors of variations in growth increment
Environment and genetics
the cross-section of a vessel.
Pore
This provides a number of features that
are of value in identification like the
shape, size, its occlusions, number and
distribution.
Pore
pipelines within
the trunk, transporting sap within the tree.
Pores
largest
type of cells
Vessel elements or PORES
Refers to the classification of hardwoods
on the basis of pore size and distribution.
Topography
radial series of adjacent solitary pores
Pore chain
pores appearing as one and
consisting of several divisions
pore multiple
tangential grouping of pores
wavy bands
Wood diameters are measured in _________
Micrometers or microns
Short-thin-walled element concerned
primarily with storage and to a lesser
extent in the distribution of carbohydrates
Parenchyma
May appear in the form of dots, lines and
bands. More abundant in hardwoods.
Parenchyma
longitudinal
parenchyma arrange independent of
vessels/pores.
Apotracheal parenchyma
refers to a tube or pipe
trachea
parenchyma cells that
occur separate from the pores.
Apotracheal
can occur as single cells bordering a
pore, called scanty parenchyma.
Paratracheal parenchyma
In some species, banded
parenchyma can also occur along
the growth ring boundary called ___________
Marginal parenchyma
It is when
both the parenchyma and rays occur
in thin, closely spaced bands forming
a net or grid-like pattern,
Reticulate parenchyma
Parenchyma may occur in
slightly narrower intervals than
the rays, appearing as rungs on
a ladder,
Scalariform parenchyma
Other parenchyma type
Boundary
Initial
Terminal
a ribbon-shaped strand of tissue extending
in a radial direction across the grain.
Wood rays
What is seen in the tangential section of a tree?
Rays arranged in horizontal
THE BASIC CELL TYPES:
A. Vessels
members
B. Parenchyma
C.Fiber
D.Tracheid
primitive element of xylem (fluid-conducting
tissues), consisting of a single
elongated cell with pointed ends and a
secondary, cellulosic wall thickened
with lignin
Tracheids
serve for support and for upward conduction of
water and dissolved minerals in all vascular plants
and are the only such elements in conifers and
ferns
Tracheids
Tracheids comprises __________ of the volume of the wood
90-95%
Vessels are composed
of elongated vessel members in
series connected by ____________
Perforation wall
primary and
secondary, lignified.
cell wall
Types of vascular rays
Homocellular ray
Heterocellular ray
defined as tracheids
present adjacent to
vessels in a wood
which also
possesses libriform fibers or fiber-
tracheids as imperforate
tracheary elements
Vasicentric Tracheids
Vascular tracheids
would correspond
with the definition of
vasicentric, but are
defined as occurring
only in latewood
Vascular tracheids
somewhat uncommon form of paratracheal
parenchyma is sometimes seen in a handful of wood species
Unilateral parenchyma
occurs when the parenchyma is so extensive that it extends outward
and makes contact with the parenchyma from neighboring pores
Confluent parenchyma
form of parenchyma that is closely related to
vasicentric
Aliform parenchyma
overgrowths of the protoplast of adjacent living
parenchymatous cells, which protrude into xylem vessels through
pits
Tyloses
a powerful tool for the identification of wood, but like all tools it must be used correctly
to take full advantage of its powers.
Wood hand lens
considered a primitive cell type that gave rise, through evolution, to both vessel
members and fibres.
Tracheids
minute units
Cells
These
cells are mainly longitudinal, or axial—their long axis runs parallel to the axis of the trunk (vertical
in the standing tree).
Tracheids
Most in demand cut in the market because it is strong
Radial cut
Basis of wood identification
Physical/structural features and anatomical features
Kaya mo pa gurl?
HAHAAHA
refers to the arrangement or direction of the wood elements particularly the
fibers in relation to the wood’s longitudinal axis.
Grain
denotes the size and the proportional amounts of woody elements in relation to the size of pores.
Texture
quarter sawn lumber
Radial face
Plain sawn lumber
Tangential face
Softwood
Conifers
Hardwood
Dicotyledons
Type of wood where rays is always narrow
Softwood
Type of wood where rays are short and narrow or wide and tally depending on species
Hardwoods
ray widths vary within and between
species.
Hardwood
_____________tracheids are
preferred for paper, since
longer fiber length is
important for paper
strength.
Softwood
articulated, tube-like structure of indeterminate
length in porous woods; formed through the fusion of the
cells in a longitudinal row and perforation of common
walls in a number of ways.
Vessel
Rays that swell at the growth-ring boundary.
Node rays
rays composed of only one type of cells,
typically only porcumbent cells.
Homocellular
portion of
ray as it appears on the
quarter surface
ray fleck
What is the distance of the eye to the wood lens?
1-4 cm
growth rings with an abrupt structural change at the boundaries between them, usually including a change in fibre wall thickness and/or fibre radial diameter,
Growth rings boundaries distinct
growth rings vague and marked by more or less gradual structural changes at their poorly defined boundaries or not visible,
Growth ring boundaries indistinct or absent
It has fibers and other elements that are generally parallel to the wood’s longitudinal axis
Straight grained
wood shows undulations in the direction of fiber alignment, or the exposed surfaces are wavy
Wavy grained
fiber alignment deviates from the direction parallel to the longitudinal axis
Cross grained
When _____ or more of the
pores in a wood sample are solitary, it is said to be exclusively solitary
90%
This classification includes
pores that are in a more-or-less horizontal (tangential) orientation.
Ulmiform
what size is 50-100 micrometers
medium
