Mountain Ash

The tall Mountain Ash trees of Mount Donna Buang, in the Alps of Victoria, were a sawyers dream when they were discovered in the 1800s. Although they tower into the air, the ones shown here are at the top of the mountain and more exposed to the conditions, hence they have a more sprawling aspect. I loved the mess and tangle of lines.

For more trees, see Becky’s squares.

Tree diagrams

Not the sole province of mathematics, tree diagrams go as far back as 1296 and have been used to organise information in every field of knowledge.

What they do have in common is a hierarchy and branches, but they can be rotated and tilted depending on the user and the purpose.

I was going to sketch up another example, but I thought I’d just borrow them from Creative Commons and square them up, and had a wealth of learning. Bits will be missing because, just like living trees, tree diagrams are rarely square.

From top left to right, we have Darwin’s tree of life 1859, a syntax tree, a family tree template, Phylogenetic tree of Theropods respiratory system, Haeckel’s foundations of science tree 1866, and one and a half medieval trees of knowledge.

But it can’t finish there, can it? I must include the famous Monty Hall Problem – that a contestant in a game show is presented with 3 doors, behind one of which is a great prize and the others have goats, or nothing. The contestant picks a door. The host reveals what is behind another door, which is (predictably) a goat. Two doors remain and the contestant is asked if they want to change their mind.

This tree looks at the probability of whether the contestant should switch.

If you’re having trouble reading it, and ever find yourself as the contestant – switch.

I’ll return to the more predictable trees in future – 100%, despite stem-and-leaf plots calling and data needing truncation.

For more tree squares, go to Becky’s challenge.

Tallest ghost

The Corymbia aparrerinja, or ghost gum, usually grows to 15m. Our star, or square, here, has been measured at 33m tall and is recorded in the National Register of Big Trees as the largest ghost gum in the country.

The stark white trunk of the ghost gum stands out against its background

As it is estimated to be 300 years old, it also appears in the Northern Territory Register of Significant Trees and it’s now appeared in Becky’s squares.

The tree’s home is Trephina Gorge Nature Park, East MacDonnell Ranges, just out of Alice Springs. Definitely worth a visit.

Salvaged trees

In 1983, Australia’s infamous Ash Wednesday II saw more than 180 fires sweep across South Australia and Victoria, in winds of up to 110km/h. Seventy-five people lost their lives, with thousands becoming homeless. Other casualties were the extensive pine forests, the biggest industry in the South East, which affected people’s livelihood.

What to do with all the burnt timber? From what I can gather, the world’s biggest timber salvage began and, up to three years after the fire, trees were collected and kept submerged or wet in Lake Bonney, a freshwater lake near Mt Gambier, for use in the decade after.

The feature bench, or series of seats, for Becky’s squares, and Xingfumamas pull-up-a-seat, were salvaged trees that were removed from water storage in 1987, sawn, dried and preservative treated to act as a lasting reminder of the fire devastation and salvage operation.

They are outside the Umpherston Sinkhole in Mount Gambier, South Australia. I believe that the timber shows no signs of damage when salvaged in this way and can be used for building, furniture and all other usual purposes.