Maize paper

Most of our paper comes from plants, but the process by which leaves and stems are converted to sheets that we can write on or wrap things in is unknown to most of us.

As part of her work with the Living Field, Jean Duncan has been making paper from plants grown in the garden.

She started with some maize, which is a tropical and sub-tropical species originally from the Americas. Some types can now grow in our climate, and it was one of these that was grown in the garden for its cobs (corn on the cob).

Jean used the maize plants to make the paper. Here is a description of what she did.

Step 1 is to collect maize leaves and stems when they are in good condition, still green.

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Step 2 is to cut the leaves and stems into small pieces. Leaf pieces should be abput the size of those in the white bowl. The tough stems were cut into larger pieces (right  below).

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Step 3 – put the cut material in an enamel bowl or pot (above left). Add soda ash to the material, 1 teaspoon for a 10 litre pot, and mix.

Step 4 – cook the plants for 3 hours, or more if the material is tough. At this point you will need pH indicator strips (litmus paper) to check that the cooking is going according to plan. (Litmus can be bought on line or at some gardening shops.) The pH of the mixture should be around 8, but if it drops to 7 or 6 then add a little more soda ash. When cooked, the fibre should be soft and easy to tear.

Step 5 – rinse the fibre thoroughly in water; when fully rinsed the pH or the water should be neutral (i.e. about 7).

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Step 6 – the fibre now needs to be beaten to a pulp. The traditional way is to beat it with a mallet for a few hours. (Craft-workers in some countries still use this method).  An alternative, if you have electricity, is a kitchen blender working in short bursts so as not to burn out the motor. Jean uses a machine called a Hollander beater.

Step 7 – the fibres are now ready to be transformed into sheets of paper. The pulp is suspended in water. A ‘mould and deckle’ is lowered into the water (image above) and brought out slowly with a flat layer of fibre on it, or else the pulp is poured into the mould and deckle until there is a flat layer of the right thickness for the type of pulp (which you work out by trial and error); the water drains out through holes leaving the moist fibre.

Step 8 – the moist sheet of fibre is  turned on to a an absorbent fabric  or board or something similar for drying and pressing, a procedure that takes about 3 days (top right in images below).

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Maize paper: lighter sheet (top left) is from the husk round the cobs, the darker sheet from stems; etchings below of root cross sections (Jean Duncan)

And that’s it – a sheet of paper!

Info, links

Khadi papers India. Web site: khadi.com. Youtube: Papermaking at Khadi Papers India

Jean’s recent work on an exhibition of etchings using her own-made paper: The Beauty of Roots and Root art.

[Update with minor amendments 10 June 2017]

The phenomenon of noctilucent clouds

Dundee Astronomical Society has been joining us at various open days for some years and has a small observatory in the Living Field garden. Ken Kennedy kindly sent us this article on noctilucent clouds for the Living Field web site. 

We all hope for a fair bit of sunshine during our northerly summer months but the suggestion that clouds may appear in the summer sky will not be a concept too alien to most of us. However, the clouds I am thinking about are not the cumulous or even stratus type clouds you may well expect on many (well, perhaps most) summer days. In fact these clouds will not be making their appearance during any summer day but could appear an hour or so after the Sun has set and disappear about an hour before sunrise.

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Noctilucent Clouds by Ken Kennedy, Dundee Astronomical Society

On June 8, 1885 Thomas Backhouse in Kissingen, Germany became aware of wispy bluish-white clouds low down towards the north and north-west following a beautiful sunset just a bit earlier in the evening. It had become quite a habit for many people to watch the sunsets and sunrises following the eruption of Krakatoa in August 1883. Many of these were quite spectacular with pink and purple colours which were the result of changes to the light of the setting Sun by particles in the upper atmosphere pushed upwards by the violence of the volcanic eruption. What Backhouse saw on the night of the 8th June, however, was rather different. These clouds were a pearly white, tending towards blue in colour, not the garish colours produced by the volcanic sunsets. It is likely to have been the colourful sunsets which allowed the discovery of these still unusual clouds as a number of historians of astronomy have failed to find any realistic reference to them before 1885.

More reports of sightings of these clouds were made and, as they were seen during the late evening and night, were given the name noctilucent clouds (NLC) or night luminous clouds. Reports and frequency of sightings gradually increased into the 20th century by which time they became a serious curiosity and were creating some questions in the scientific world. It was generally agreed that rising warm air cools and moisture carried by that warm air forms water droplets as the air ascends. These form clouds which could extend upwards to around 15km. Beyond this, very little water could be carried, and certainly not sufficient to form these clouds which had been measured to be at the remarkable height of around 83km. The clouds are formed of ice crystals and are illuminated by the Sun which is between 6 and 16 degrees below the observer’s horizon. James Paton, the then Director of the British Astronomical Association’s Aurora Section made an extensive study of NLC from his home in Abernethy until his death in 1974. Dr Mike Gadsden of Aberdeen University continued to make a detailed study of NLC from the Cromwell Tower of Aberdeen University until his death in 2003. I remember well Mike saying to me ‘These clouds shouldn’t exist. There should not be enough water at that height to allow visible ice clouds’. He also was the first person I heard who suggested that NLC may be a barometer of global atmospheric change (he said this before the phrase ‘global warming’ became popular).

[Continued ……. ]

Ken continues to explain how noctilucent clouds form, describes their role in space science, notably via the findings of the AIM (Aeronomy of Ice in the Mesosphere) satellite and points to the importance of the sun’s cyclic activity (sunspots) on their recorded occurrence. His article can be read in full at the DundeeAstro page on this web site Clouds on the summer horizon. With thanks.

Dundee Astronomical Society
Noctilucent Clouds by Alan Tough, Dundee Astronomical Society