Lec 18 - Wood and Wood Products Flashcards
wood once used in
golf clubs and hockey sticks
tree:
erect, single stemmed woody plant that can exceed 6m in height
tallest tree + info:
Coast redwood in californa (115.7m)
tree can stand due to
secondary trees
for a tree to grow in girth, it must be capable of producing
“secondary growth”
are bamboo and banana trees? why?
no. because no secondary growth occurs in monocotyledonous plants
the ____________ is required for secondary growth
lateral meristem vascular
vascular bundles present:
- fasicular cambium and interfasicular cambium fuses
- vascular cambium grow and form to inside and outside
wood:
a combo of xylem vessels, tracheids,divers and parenchyma
how do rings occur in wood
- since wood produced is older than spring wood vs summer wood
- due to less water, less cell growth, means smaller rings
- ## new cylinders of secondary zylem a year produced
heartwood cant transfer water due to
resin which prevents decay
dendrochronology
the study of tree rings
- rings with living trees are matched with fallen trees to produce a record
who does dendrochronology work?
a tool is punched into the tree, a cork is retrieved so the rings can be counted
dendroclimatology used to determine
- if droughts occurred in cyclic patterns
- indicates impact of pollution, pests, forest fires, volcanoes, and earthquakes
wood hardness
relates to sturdiness of cell wall
sturdiness of cell wall due to
cellulose and lignin content
hardest wood
lignun vitae (density 1.37g/cm^3)
what wood has the ability to float
balsa wood
hardwood consists of
a combo of xylem vessels and tracheids
hardwood is from what plants
angiosperm trees
softwood is from what plants
gymnosperms
softwood consists of
solely tracheids
wood characteristics of appearance
- # of rays
- porosity (in hardwoods)
- arrangement of annual rings
- presence or absence of knots
- grain
how can termites digest wood?
- protist symbiotic relationship between termite and protist bacteria break down wood in pieces
- enzymes break down proteins in wood
what lead to the decline of white pine (timber tree) in North America
a fungul disease
what wood does not warp
white pine
what wood is used in plywood production
Douglas fir
what woods are used for furniture
white oak and ideally black walnuts
what wood is 1% (150,000 trees) of all wood utilized in ikea furniture
black walnut
nearly 1/2 of wood produced in industrialized nations used for
pulp
wood pulp
a watery suspension of pulverized wood
____________________ of wood is critical for pulp production
de-lignification
lignin can be turned into
vanilin (a vanilla substitute)
what is environmentally costly in pulp production
lignin removal
charcoal
pure carbon and can yield a flame at a high temp
