FBS 10 Lab Exer 4, 5a

• Cylindrical bole

  • trunk is not tapering
  • circular top view
• Tapering bole

  • decreasing perceptively from base to top
  • forming triangle shape
• Fluted bole/stem form

  • irregular in cross section and with conspicuous vertical ridges, and rounded, shallow and concave grooves or furrows in the bark along the length of the bole
  • flower shaped top view
• Latticed bole/stem form

  • a structure of crossed pattern usually arranged to form a diagonal pattern of open spaces between the strips
  • not common in TRFs
• Smooth bark


  surface is even and generally unbroken
• Fissured bark


  bark is cracked with narrow furrows or grooves which are irregularly interconnected
• Scaly bark


  with small detachable scars and are quite large generally not longer than eight cm
• Flaky bark


  the detachable scales are quite large, generally longer than 8 cm
• Thorny bark


  with stiff sharp spines or prickles; for predatory purposes
• Pustulated bark


  characterized by conspicuously raised areas or swellings due to the lenticels or to natural pruning of small branches
• Pocked-marked bark


  with conspicuously deep areas or dents due to removal of thick circular plates of the bark; similar to flaky and scaly but the removed part is generally thicker
• Excurrent branching pattern


  The main trunk goes the entire height of the tree, with branches forming patterns; e.g., pines and evergreens
• Decurrent branching pattern


  the main trunk continues up about halfway (no branches yet), then splits into more than one main branch to forma a spreading crown; e.g. fruit trees
• Columnar/Caudex


  the main trunk continues the full height of the tree, with the branches forming only at the top(apical meristem); e.g. palms
• Branching pattern (Formation of branches on the main stem)

  • orthotropic: growth is upright and stem symmetry is typically radial
  • plagiotropic: horizontal, often associated with bilateral symmetry
• • Some stems can be orthotropic then plagiotropic, or vice versa; they are called mixed axes
  • Some stems have no particular orientation and are called ageotropic
• Phyllotaxy


  arrangement and position of the branches on a tree
• Opposite arrangement


  branches grow from the opposite side of the trunk, across from each other
• Alternate arrangement


  branches grow opposite to each other, but one will be further up the trunk than the first
• Spiral arrangement


  branches grow alternately along the trunk, but in a spiral pattern like a corkscrew, moving up the trunk
• Whorled arrangement


  branches are attached in a group of 2 or 3 from the same location on the trunk
• Pseudobark


  consists of a thick layer of sclerified tissue and is made of cortex with very thin epidermis
• Leaves are formed from meristematic tissues located in the shoot tip called primordia
• Axillary buds are in specific locations and their final shape results from cellular division and expansion
• Simple leaves have a flattened blade or lamina and a stalk called petiole
• The lamina of compound leaves is divided into leaflets that form one plant and lack axillary buds.
• Phyllotaxis (from the Greek word phyllon, meaning “leaf” and taxis, meaning “arrangement”) is the arrangement of leaves on a stem.
• When pairs of successive nodes form right angles to each other,

  the phyllotaxis is decussate.
• Monocot and dicot common leaf parts:

  • blade
  • petiole
  • midrib
  • veins
• Monocot has ligules and auricles at the base of the leaf sheath that both function for protection against dust and other dirt.
• Stipule (small leaflike structure at the base of the petiole) is a feature that is shared only by the members of dicotyledon.
• Leaves are a highly variable plant organ that can be characterized using the following characteristics:

  1. Leaf composition - simple or compound
  2. Phyllotaxy – leaf arrangement which can be opposite, alternate, spiral, whorled
  3. Venation - arrangement of veins (netted, pinnately veined, palmately veined)
  4. Lamina characteristics such as apex, margin, base and shape
• Leaf Modification

  Scale-like - leaf shaped like a small awn or scales for

  protection during harsh weather condition, common

  among temperate species like Norfolk Island Pine.
• Leaf Modification

  Needlelike - long, slender, tubular or triangular leaf and

  usually attached in a fascicle (Example Benguet pine,

  Pinus kesiya)
• Leaf Modification

  Bract - a modified (often reduced) leaf holding a flower or

  flower cluster, usually colored mimicking petals (Poinsettia,

  Bougainvillea and Mussaenda); it can also be green as in

  the case of most lilies
• Leaf Modification

  Phyllodes - modified petiole or rachis of a leaf flattened for

  photosynthesis as the lamina is poorly developed.

  Example: Rusty banana (Heliconia angustia)
• Leaf Modification

  Bulb - presence of fleshy scaly leaves with storage functions

  (members of Lily family like onions)
• Leaf Modification

  Succulent - thick, fleshy leaf, usually modified for water

  storage (Aloe Vera, Sedum, banana)
• Leaf Modification

  Leaf Tendril - slender, twining modified leaf (or stem) used for

  clinging to objects for support. It may come in various forms

  which range from leaf apex, stipular, leaflet tendril, or leaf

  petiole tendril.
• Leaf Modification

  Spine - a leaf or leaf part modified into a sharp point (Date

  Palm, cactus)