24th September 2018
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Beaches strain with pulverised seaweed

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While the rest of Britain is gently vanishing under a blanket of snow, Shetland gleams in the brilliance of winter sunshine and recent gales have subsided, leaving beaches groaning under the weight of fresh­ly cast and pulverised seaweed.

It’s time to get the sacks out and head for the shore. Tonight I will have hands as smooth as silk, after a rich, deep seaweed treatment session. But with luck, I may find a few marine treasures too in the process.

As usual, nearby sheep begin to stream downhill, finding a crack in the fence and gradually engulfing us in shunting damp, fleecy bodies and raucous baaing. But resolutely, somewhat stiff and awkward under too many layers of jumpers, breeks and boiler suits, we waddle to the strand line. An hour later, the car laden and smelly, hands frozen and noses needing hankies, we return home. I have a single treasure, safely housed in my top pocket.

At first glance, it looks like a small flap of kelp, with a greyish blob in one corner. Closer inspection reveals the blob to be a small patch of minute, geometric patterning. A hand lens brings it into sharper focus. The pattern consists of white rectangular outlines, all perfectly aligned, bonded like tiny bricks and made of something extremely fine, white and presumably very strong. They have obviously withstood immense forces of abrasion and battering, judging by the smashed fragment of weed, which has been torn and cast onto the beach. The small patch of tessellated rectangles is a sea mat.

Sea mats, or Bryozoa, are colonies of tiny animals, which can be found growing on rocks and seaweed around coastlines all over the world and Shetland has several kinds. All the little cells were ragged and broken.

When living, each cell apparently has a mass of tiny tentacles and moving hairs which help create currents, sweeping miniscule food particles into their mouths. These moving hairs can create a furry, almost mossy appearance to the mat, hence their name; Bryo, meaning moss, and Zoa, animal. Moss animal! My specimen proved to be dead, once properly scrutinised under a binocular microscope. But the walls were distinct enough to seek identification. Out of all the examples revealed in my Collins Guide to the Seashore, I settled on the illustration most closely resemb­ling the one in front of me, rather grandly called Membranipora mem­branacea. Others on the same page had very different structures, but they were intriguing and I shall certainly keep an eye open this year in the hope of seeing a few more moss animals.

The sea has been spring cleaning its shaggy shallows, heaving up tons of loose material and the spring fever has been nagging me too. As a keen collector of what used to be called geraniums, I have windowsills which regularly collect their shed petals and leaves. But my attempts to clear them and throw away the dead bits failed miserably this weekend, as I found something very different among the litter. Seed heads.

So the next section is especially for lovers of Lady Plymouth, Lord Bute, The Boar, One in a Ring and all their friends.

Watch out, don’t throw out those shrivelled up seed heads, there are extraordinary things to be seen. I know that window sills gather dust, that which used to be loosely termed indoor “geraniums”, now called pelargoniums, drop their old leaves and petals far too frequently for tidy folk to stand, but bear with me. Fish among the scraps and pull out a single dry, dead seed head.

The petals have long since faded and crumpled. But from the centre of a few of their dried up clumps a long, dry spear has risen up. This seed head, with its firm, rounded blob at the base, and the tall spike reaching out from it, resembles the head and bill of a stork, or a crane. Folk familiar with these birds will see the resemblance at once. In the geranium family are some old Shetland favourites: storksbill, mea­dow cranesbill among them. These seed heads give them their common names.

But the really exciting events come later. I have an old flowering head on the table beside me and with a bit of luck it will perform its tricks right here. Depending upon how dry it is, what the weather is like and how much indoor heating and humidity is affecting it, the seed will begin to move.

Plants aren’t generally considered to be things that move independently, but these seeds can break the rules. Watch the process closely. What happens is the same for all the five seeds in the seed head, but to follow the action clearly, I will describe just one of them.

First a long, thin, wiry appendage begins to separate itself from the “beak” part of the seed head. It forms a loop, attached at both ends. Eventually the lower portion, revealing itself to be a short, stubby, pointed seed, is pulled out of the old flower base.

The tip of the wiry extension still clings on. But it is changing its appearance. No longer is it thin and dark. A silvery edge is developing along the inside next to the shaft. Something gorgeous is beginning to thrust its way out of the shadows.

A few minutes pass. The seed is now well clear of its socket and gradually rising upwards, at the end of the “wire”. The silvery effect is revealed to be a kind of comb of pure white, shining filaments, attached all the way up from the tip of the seed to the very top. They slowly fan out, catching the light, for all the world like silk, or glass fibre. The entire structure, seed and shining tail, still pinned to the tip of the “beak” now begins to twist. I am describing one seed, but the same thing is happening to the remaining four seeds too.

The twisting process causes the seed to revolve slowly in mid air. The widening fan of filaments is curled up on itself, the fibres stiff and gossamer fine, stretching out like the spokes of a delicate wheel, minus the rim.

The curling continues, but up­wards as well as inwards and the dark, wiry shaft becomes a tight spiral, twirling away from the seed. Each of the five seeds has now similarly left its moorings, has risen and twisted upwards and each is held out away from the central beak, with its twirling silvery fan and spiral.

The effect is strikingly beautiful. How I can have kept geraniums, sorry, pelargoniums for 20 years and never properly noticed before, I can’t imagine.

Before us now stands a sym­metrical figurine, a radiating balance of curved rays, small, dark seeds suspended outwards from coils of silvery fringed tight spiral wires, taut, tense, ready to spin off like an unwinding heliblade into the ether; and in fact, that is exactly what it wants to do. For the frail, rotary feathers are now ready to fly, or rather float and drift in the breeze, ferrying their seed to a place where it can land and germinate into a new plant.

The wonderful, poised structure, beautiful as it may be, is simply a practical, ultra technically designed organ for production of more of the same. But, as Darwin, much in the news just now, made clear, it wouldn’t be the same; not exactly the same.

Whatever air current or insect enabled the pollen from one of last year’s flowers, to reach the stigma of another pot plant’s flower, brought a different range of genes into the picture. It’s worth a few minutes needed to get a plant pot, some compost and a label, to tuck these seeds into the soil and see what results in due course.

What I hadn’t realised at first, was that the seeds, in the wild, continue the spiralling action even when the seed lands. Through a process called hygrometry, minute changes in humidity cause the seed and its tail to twist the seed down into the soil, until it is firmly embedded. Apparently, a handful of these seeds, if laid in a small dish and carried into different rooms, will start to move about, as they experi­ence changes in humidity levels.

The outer skin of the seed is rough, but not randomly rough. The minute irregularities act as ratchets, allowing tiny movements down­wards, but locking each time, pre­vent­ing any possibility of escape. The clever tricks department of nature has really excelled itself with this set up. So why not take a chance?

If you have window sills or conservatories with favourite old pelargoniums in, try to breed a new one this year. Set a few of these glorious little feathered seeds and see what comes up. It will take a while for the plants to reach adulthood and flower, but who knows? You may be lucky, and land a real treasure. I must go and find a pot and a “gyoppmfoo o moold” while the resolve lasts.

Jill Slee Blackadder