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Trees and seeds
Clementp.fr CCA-S A 4.0 International
For a few days in 2023 this tree was the most famous tree in the world.
Sited in a break in Hadrian's Wall in the north of England, the tree was known not just to a handful of walkers, but to millions across the world who had seen it in a popular film.
On the night of 28 September 2023, the tree was cut down in a mindless act of vandalism. Sadly the world is used to daily acts of terror against mankind, but this was something else – ignorant, pointless barbarity against the natural world which nurtures us as a species, an assault even on beauty itself. For those few days it was so much more than just a tree.
The tree was a sycamore (acer pseudoplatanus), one of the commonest trees in the UK, and identifiable by many due to its unusual seedpods. Each seed is attached to a small 'tag' or 'winglet', which due to its shape causes the seed to slow down and rotate as it falls through the air, so often described as like a 'helicopter'. The proper name for it is a 'samara'. A similar feature is seen not just in the sycamore but in the rest of the acer (maple) family and several others.
Janny 2/ istock
The basic problem is clear.
If a tree sheds its seeds and they fall to earth only under the influence of gravity and a temperamental breeze, they will land mainly within the area of the parent tree's canopy. There they will be sheltered from rainfall and sunlight, and be competing with the host tree for soil nutrients – not a good place for a single seed to germinate alongside 100s of others. The search is on for a way of dispersing the seeds more effectively over a wider area.
This arrangement is distinctive
and clearly purposeful, and a number of scientists have examined it over the years to see exactly how it works.
In July 2009 Science Magazine published an article 'Leading-Edge Vortices Elevate Lift of Autorotating Plant Seed', which explains the precise aerodynamics of how the samaras spin through the air:
"..the scientists found that the swirling seed generated a tornado-like vortex that sits on top of the front leading edge, which lowered the air pressure over the upper surface of the seed, effectively sucking it upwards to counter the gravitational pull. Sycamore seeds, by creating this vortex, achieve twice the lift that non-swirling seeds can....a sycamore seed twizzling through the air is not just one of nature's more remarkable autumnal sights.
It's also a masterpiece of Nature's aerodynamics."– Country Life Magazine.
Just as remarkable is the writer's appeal to a nonsensical, undefinable concept called 'Nature'. It seems anything will do, provided it's not a designer or Creator!
The whole subject of 'seed dispersal' is the subject of a comprehensive article in Wikipedia. But there is one outstanding example which caught the attention of some of the early pioneers of human flight, going back to Igo Etrich and the Horton Bros in the early 1900s, and two Japanese engineers Akira Azuma and Yoshinori Okuno some 30 years ago. It is the seed of the alsomitra vine, from Java, Indonesia.
1912
The beginnings of human flight:
design studies for a glider by Igo Etrich, starting with the alsomitra seed (top left – alsomitra was then classified as zanonia).
The alsomitra vine – design for flight
The alsomitra vine, otherwise known as the 'Javan cucumber', is a climbing gourd which relies on another tree for its support. Once it is way above the forest floor it developes a very large (football-sized!) seed pod.
This pod contains about 400 seeds. Each seed is flat and integrated into the centre of its own wing. The seed is very light and thin (about 1mm thick), the wing even thinner, a flat translucent material in an overall double winglike shape, and 130 to 150 mm wide (around 6", see picture). When the time is right, the seedpod with its 400 seeds opens and each seed is gently released, one at a time, into the air. The wing responds to air pressure by curving into a shallow bird-like profile, settles into a slow gentle and stable glide which can take it sometimes hundreds of metres from the host vine.
The idea of a 'flying wing' was once popular amongst model aircraft enthusiasts, but never found any commercial application. The material of the alsomitra wing is assumed to be a cellulose product – the photo above shows it as a soft, fabric-like material, not the stiff card-like material we might imagine. Examining it In the 1980s two Japanese engineers found:
“The geometrical characteristics of the wing of Alsomitra macrocarpa, such as the slightly swept and twisted wing, the reflected trailing edge of the airfoil, the lightly loaded wing and adequately arranged CG [center of gravity] position, are well fitted to assure the good performance and stability in gliding flight of the winged seed."– Azuma and Okuno 1987:264
Once the flight is complete, the wing rots away very quickly and leaves the seed to germinate where it has landed.
So there you have it – a perfect micro-glider, assembled (grown) from scratch, but, we are told, without intention, knowledge or expertise, by an innumerable series of highly unlikely tiny accidents, and, by astounding good luck, a unique model of design for human flight.
A well known astronomer, Johannes Kepler, coined a famous phrase.
He said that science was like 'thinking God's thoughts after him'. We are the only creatures in the universe capable of doing that, gifted as we are with some element of the divine intellect that enables us to follow his mind, to 'think his thoughts.' When we probe the miracles of design with which he has filled our planet, we learn to think as he does – and when we think like God in every sense, we become as God wanted us to be; we become the 'image' of our Creator. (Genesis 1: 26)
Meanwhile, back in Northumberland,
the sycamore has switched to survival mode (another miracle of programming!). Within a few months the first green shoots of recovery appeared that may one day produce a great tree to replace its ancestor:
Northumberland National Park.org.uk
"...there is hope for a tree: if it is cut down, it will sprout again, and its new shoots will not fail..." Job 14:7
In the bleak materialism of today's world, HOPE is what God gives us. We may be cut down, we may die and rot, but God has given us the hope of recovery, healing and new life:
"...to you who fear my name the Sun of Righteousness shall arise with healing in his wings..." Malachi 4:2 NKJV
"For as the soil makes the sprout come up and a garden causes seeds to grow, so the Sovereign Lord will make righteousness and praise spring up before all nations." Isaiah 61:11