- Newest: The genus Dawn Redwood (Metasequoia) had only been seen as a fossil
and was thought to be extinct until a living tree was discovered in China in 1941.The tree,
now known as the species Dawn Redwood (Metasequoia glyptostroboides), is a deciduous
conifer. One of these special trees was planted some years ago in the Dominion Arboretum in Ottawa.
When, camera at the ready, I found its location one cold. windy day in April 1996, it was only to
discover that the major part of the tree had been cut down the day before. However, one shoot,
about 8 ft. high, remained and so all was not lost. It should be interesting to see what the
future holds for this sapling; I believe its habitat is somewhat south of Canada. A Virginian
tells me he has a beautiful 50 foot Dawn Redwood in his backyard. Lucky him.
But, just recently, I've discovered that there's a new kid on the block.
The Wollemi Pine, Wollemia nobilis, was discovered in August 1994 in the Wollemi National Park
about 200 miles north-west of Sydney, Australia. The tree is another "living fossil", a new
genus and species in the ancient conifer family Araucariaceae. Fossils of this tree date back to
the Jurassic Period -- the age of the Dinosaurs. There are only 40 mature trees, making the Wollemi one of the
world's rarest species.
- Sole Surviver of a Family: The Ginkgo biloba is the only surviving species
of the family GINKGOACEAE (SE China).
- Oldest: The ancient bristlecone pines (Pinus longaeva)
in California, Utah and Colorado. They are known to live more than 4000 years.
- Most Beautiful: The Horse-chestnut in full bloom,
"in all the richness of its heavy velvet
drapery,
embroidered over with millions of silver flowers."
-- Author unknown.
Second place to the Mountain Ash, Rowan,
"She lifts her head,
Decked with
autumn berries that outshine Spring's richest blossoms"
-- Wordsworth.
- Tallest: The giant redwoods (Sequoia sempervirens) in
California (about 112 metres), and the Eucalyptus regnans in Australia
(about 107 metres).
- Shortest: How about the
Weeping Mulberry?
It's not even as high as an elephant's eye.
- Biggest Trunk: A Taxodium mucronatum in Mexico is reported to have a
circumference of 42 metres which equates
to a trunk diameter of approximately 13.37 metres (almost 44 feet). Elsewhere it
is reported that the diameter is 52 feet. Would the real Taxodium please stand up.
Further investigation is required -- I'll to have to check this one out myself.
The tree is reported to be over 2000 years old.
- Heaviest: Black ironwood weighs about 81 lbs/cu.ft. (specific gravity = 1.30);
Lignumvitae about 78 lbs/cu.ft. (sg = 1.25). They do not float well!
(specific gravity of water = 1.00)
- Lightest: Balsa weighs about 7 lbs/cu.ft. (specific gravity = 0.11). It floats
so well it almost jumps out of the water.
- Stiffness: The Modulus of elasticity of wood, a measure of its stiffness,
is about 1/15th that of steel.
- Sweetest Smelling: ????
- Foulest Smelling: Pride of place goes apparently to the fruit of the Ginkgo. I
can't verify.
- Hardest: I suppose that depends on your definition of hardness.
Dictionaries define hardwood as the wood of deciduous
trees as opposed to conifers.
Generally, hardness is thought of as resistance to indentation
but exactly how
the terms hardwood and softwood were chosen originally does
not appear to be known. It would
appear that the terms are not now as meaningful as they were several
hundred years ago.
Many of the mechanical properties of the two groups are quite similar but,
considering timber used in construction, there is a significant difference
between the two groups in the properties of shear strength and the effect
of temperature. In any case, it would be an interesting project to
determine the history of the names: hardwood and softwood; I
wonder when the words first appeared in dictionaries?
- What makes the sap rise?:
- Poisonous Trees?:
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