LectureNo. 2
HAFIZ MASOOD AHMAD
Lecturer
Department of Forestry &
Range Management
University of Agriculture, Faisalabad
FUNCTIONAL TREE
MORPHOLOGY
Total tree species in Pakistan = 430
Broad leaved/ Angiosperm/ Hard wood species =
408
Conifers/ Gymnosperm/Soft wood Species= 22
Total tree genera =226
Genera belonging to Broad leaved trees =215
Genera belonging to conifer trees = 11
Total tree families =82
Families belonging to Broad leaved trees = 77
Families belonging to conifer trees = 5
TREES IN PAKISTAN
PARTS OF A TREE
Crown
Stem/Bole/Trunk
Roots
Definition
The head of a tree
consisting of leaves,
flowers, seeds, twigs,
branches and limbs.
Function of Crown
Making food for the
tree
CROWN (The Head of a tree) (i)
CROWN (The Head of a tree) (ii)
Various Parts of a Crown:
Leaves
Flowers
Fruits
Seeds
Twigs
Branches.
Limbs
CROWN (The Head of a tree) (iii)
Leaves:
Leaves are the green, flat, lateral outgrowth in
plants.
These are generally dorso-ventrally flattened and
thin.
Functions of Leaves:
These are responsible for photosynthesis as they
contain chlorophyll.
Respiration also take place in leaves
CROWN (The Head of a tree) (iv)
Types of Leaves :
Needle Shaped Leaves vs
Broad Leaves
Simple Leaves vs
Compound Leaves
Large Leathery Leaves vs
Small Scaly Leaves
Types of LeavesExamples of Trees
Needle Shaped
Leaves
ChirPine (Pinusroxburghii),
Blue Pine (Pinuswallichiana),
Chalghoza(Pinusgerardiana),
Deodar (Cedrusdeodara)
Broad Leaves Shesham(Dalbergiasissoo),
Mulberry (Morusalba),
Simal(Bombaxceiba),
Neem(Azadirachtaindica)
CROWN (The Head of a tree) (v)
Types of LeavesExamples of Trees
Simple LeavesPoplar (Populusdeltoides),
Bargad(Ficusbengalensis)
Peepal(Ficusreligiousa)
Mulberry(Morusalba)
Compound
Leaves
Sohanjna(Moringa oleifera),
Kikar(Acacia nilotica),
Neem(Azadirachtaindica),
Bakain(Meliaazedarech),
CROWN (The Head of a tree) (vi)
CROWN (The Head of a tree) (vii)
Flowers
Small, dull colored and inconspicuous.
Pollination is generally by wind in tree species.
Parts of a Flower
Most flowers have four main parts:Sepals, Petals,
Stamens, and Carpals
Function of Flowers
Reproduction, Pollination
CROWN (The Head of a tree) (viii)
Seed
Important regeneration source of plants
Parts of Seed:
Endosperm i.e. Food storage chamber
Embryoi.e.Future plant or baby tree
Testai.e.Protective cover.
PlumuleFuture shoot
RadicleFuture root
CROWN (The Head of a tree) (ix)
Seed Characters:
Some seeds germinate on the tree but some after
falling.
Some seeds undergo dormancy.
Some seeds have very short viability e.g. Neem
and Jaman
Some seeds have very long viability e.g. Kikar,
Naked seeds are present in Gymnosperm
While in Angiosperms,seeds are enclosed in
fruits
CROWN (The Head of a tree) (x)
Twigs:
Small branches of thumb thickness or less.
Woody in nature.
Entire tissue is alive.
Function of Twigs:
Support the leaves, flowers, fruits and seeds
Transport water, nutrients and food
Vegetative reproduction
CROWN (The Head of a tree) (xi)
Branches:
Larger twigs
Woody in nature.
Thickness varies from thumb to wrist.
Central core of branches is generally dead.
Functions of Branches:Same as twigs
Support
Transport of food, nutrients and water
Storage of food, nutrients and water.
Responsible for giving proper shape to the tree
Limbs:
Larger branches over wrist thickness
Woody in nature
Some times central core is dead
Can be used as fuel as well as for timber
purpose
Function of Limbs: (same as branches)
Water, nutrients and synthesized food move
through the limbs
Limbs support the branches and twigs
These are also used for food storage
CROWN (The Head of a tree) (xii)
Central part of a tree that is above roots and
below crown
Consist of dead bark (dead phloem), living
bark (living phloem), cambium, sap wood
(living wood), and heart wood (dead wood).
Most important and useful part of tree.
Woody in nature.
Central core is dead.
Round cylindrical shape
Having tapering
STEM
Function of Stem:
Mechanical Strength
Stem supports limbs, limbs carry branches,
braches carry twigs and twigs carry leaves,
flowers, fruits and seed.
Stem also transport water nutrients and food in
the tree.
Source of wood
STEM
Wood:
Central core of stem (Dead xylem tissues)
ANATOMY OF A TREE STEM
Sap wood/Living wood/Living xylem
The soft outer layers of recently formed wood
between theheart wood and cambium, containing
functional vascular (xylem) tissues.
It is light colouredregion of the tree trunk
consisting of living wood cells and helps in
translocation.
Function of Sapwood
This layer transports water and nutrients from soil
to leaves
PARTS OF A TREE STEM
Heart wood/Dead wood/Dead xylem
Central core of dead xylem surrounded by thin
layer of living xylem
Heartwood is the inner dark colouredpart of the
wood of tree composed of dead cells filled with
resin, gums, tannins, etc.
Function of Heartwood
Deposition of food and waste products in central
woody cells and in canals.
PARTS OF A TREE STEM
Vessels:Larger woody cells with partially or
completely open end walls found in broad leaved
tree species (Angiosperms).
Distributed uniformly throughout the cross
section or concentrated in the form of rings.
Trachieds:Large woody cells with oblique end
walls found in conifer species (Gymnosperms)
Fibers:Long narrow woody cells with pointed
ends like spindles found in broad leaved tree
species (Angiosperms).
TYPES OF WOOD CELLS
TYPES OF WOOD CELLS
TYPES OF WOOD CELLS
Parenchyma cells: Wood cells thatfunction
primarily in the storage and conduction of food
materialsare known as parenchyma cells. These
cells typically form thin secondary walls and are
the last to remain functional prior to heartwood
formation.
Ray cells:Living parenchyma present in radial
direction are also called Ray cells.
Canals:Central ray cells collapse and give rise
to canals
Cambium: Living xylem is surrounded by a
narrow layer of growth cells that is called
cambium.
It exists inside of living bark (living phloem) and
out side of living wood (living xylum)
Functions of Cambium
Responsible for lateral growth
Produce xylem cells (wood cells) Inside and
phloem cells (living bark) outside.
PARTS OF STEM
Phloem:Living phloem is living bark while
dead phloem is dead bark
Function of Phloem:
Transportation of synthesized food.
Bark: The outer most layers is called bark
consisting of phloem.
It protects the inner living layer form extreme
temperature, drought and other factors.
Bark yields important tree products like tannin
and cork for bottle stoppers and insulation.
PARTS OF STEM
FORMATION OF ANNUAL
RINGS IN TREE STEM
Spring & summer wood cells = larger
Autumn & early winter wood cells = Smaller
Both layers can be easily distinguished.
Annual ring or annual growth layer:
A layer of spring/summer cells and a layer of
autumn/winter cells is collectively called Annual
ring
Layers are generally visible, indicate the age and
growth of tree (more prominent in conifer trees).
STRUCTURE OF ROOT
Root: Underground part of the tree, consisting of
woody and fibrous parts.
Woody part provide mechanical support,
transport and storage of food.
Two types of roots: Tap root and Fibrous root
Structure of Root
Central core dead xylem
Many conductive tissues; mostly dead
Conductive tissues of outer periphery; most of
are alive and functional.
STRUCTURE OF ROOT
Endodermis:The central core is surrounded by
a single layer of tightly packed, cemented cells
called endodermis
Function of Endodermis: Controls the
movement of water and solutes. Degree of control
depends on vigor of cells.
Cortex:The next layer is called cortex. These
are loosely packed living parenchyma cells.
Provide cushion & lubrication.
Corky tissue: Outer most layer is corky tissue.
Waste products are deposited in it.
STRUCTURE OF ROOT
Thin and Long, consist of few bundles of
conductive tissues
Two additional structure, i.e. Root cap & Root
hair
Root Cap:It is at the tip of fibrous roots,
consist of loosely packed living cells & provide
lubrication.
Root Hair:Single celled appendages, increase
the area, absorb nutrients and water.
Root surface area is 2-3 times more than leaf area
STRUCTURE OF ROOT