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Horticulture Group Newsletter - July 2013

tomato slice

1 Jul 2013

Earlier this year the Group joined with the Professional Horticulture Group South West for a visit to Branstons, a major potato marketing organisation supplying UK supermarkets. A full report appears below.

In June members of the Group were treated to an informative mid-summer's day tour of the Harcourt Arboretum, part of the Oxford Botanic Garden which is also reported below.

On 3 July the Society will hold its Annual General Meeting and all members are encouraged to attend. The day will include the award of the Lampitt Medal, a presentation by the 2013 Seligman Fellow and the Annual Summer Lecture by the Society's Honorary President Mr Paul Booth. Details

Later in the month we will again join with the Professional Horticulture Group South West for a visit to Avon Bulbs and the National Trust Gardens at Tintinhull. Details will be posted on the website as soon as possible but for now please email.

Editor

Branstons Potatoes

Ian Waite, photo by Peter GrimblyThe Branstons unit at Seavington St Michael is part of a Lincolnshire based company; one of the largest buyers, packers and distributors of potatoes in the UK. The company was started as a grower cooperative by a group of Lincolnshire potato growers around the village of Branston a few miles south-east of Lincoln. A similar cooperative was formed near Seavington St Michael, eventually joining with Branstons in Lincolnshire.

The packing station was built on a piece of land owned by one member of the cooperative luckily now close to the upgraded A303. However access to the site and the A303 remains via a single track road - less than ideal for the large lorries bringing potatoes in from the 48 growers in the group and delivering to their customers.

Ian Waite, general manager of site (pictured right), explained the history of the company which now includes a Scottish unit at Abernethy in Perthshire. He then took us on an escorted tour in which we were accompanied by Operations Manager, Nick Brake, and Agronomist, Pascal Myles. We started where the potatoes do, at the weighbridge.

As each lorry arrives from the grower, with some of the 82,000 tonnes of potatoes that pass through the packing station, the contents are weighed. 10kg samples are washed and then assessed for quality, looking for skin defects, blemishes and disease. They then either go to cold store or are immediately graded. Potatoes due for eating are stored at 3°C while those for processing at 8°C.

The majority of the potatoes passing through the site are destined for Tesco which orders early each morning. These must be ready for dispatch by 3pm each day.

Potatoes are first graded for size by passing them across vibrating belts with holes of the appropriate diameter. The vibration is essential since, as everyone is aware, few potatoes are conveniently round and they need to be shaken to ensure they are presented to the grading holes in a variety of attitudes. The graded potatoes are then washed, polished to remove any residual soil, before being colour graded.

Branstons grader - photo by Peter Grimbly This is intended to remove as many diseased and green potatoes as possible. However, it only works with uniformly coloured potatoes so varieties like King Edwards, which have red patches, have to be graded entirely by hand. They are re-graded and a final manual quality check made before being packed.

The packing machine itself is an ingenious gravity-fed system (pictured right). Cleaned and graded potatoes fall into one of 16 weighing cups. A computer then works out which combination of 2, 3 or 4 cups contains the nearest approximation to 2kg before opening the respective traps to allow those to fall into the bags below. A final check of the completed bag weights is made before they are boxed for delivery to the customer.

The company would normally aim to fill the majority of their orders from home-grown potatoes. However, last summer's wet weather created major shortages, with growers finding it difficult to lift the crop, and large losses when they did. As a consequence they were forced to import potatoes from France and further east.

All UK growers conform to Tesco's 'Nurture' standard of husbandry. However, when the company has to import to fill shortages, it relies on similar EU standards which, although slightly lower, are still high enough to be acceptable.

In addition to the 2.5 million packs supplied to Tesco each week, larger bags are also sent to other customers.

Washing potatoes inevitably results in large volumes of muddy water. This is all passed through a recycling plant where a combination of flocculation and filtration removes the soil and enables 80% of the water used to be recycled.

Peter Grimbly

Harcourt Arboretum

Harcourt Arboretum - photo by Peter Grimbly The core of this arboretum was originally planted in the 1830s by Archbishop Vernon Harcourt, who lived at nearby Nuneham House and many of his original trees still survive. Today it forms part of the Oxford Botanic Garden, providing a larger site with a distinct soil type broadening the range of plants that can be grown and used for the university.

Our guide for the day, Senior Curator Alison Foster, explained that the artist, William Sawrey Gilpin (more), was involved in the original plantings, although there is some doubt as to the extent of his involvement. The Botanic Garden acquired the arboretum in 1963 and, over the last 50 years, purchased additional land and now covers 130 acres. Much of this land has not been used to extend the tree planting, but to create permanent wildflower meadows.

Our tour started in the rather prosaically entitled 'Pylon Meadow' (pictured right), named after the high voltage electricity pylon that stands in the middle. This is the oldest established of the meadows and has a wide range of species with the meadow buttercup, Ranunculus acris, very much in evidence at the time. Scattered plants of the hemiparasite yellow rattle, Rhinanthus minor, were also visible and, in one area where it was particularly dense, the dwarfing effect of its parasitism on the grasses was very apparent.

Harcourt Arboretum - photo by Peter Grimbly We then moved on to the newer more recently established meadow. This had been planted over a three-year period using seed collected from the pylon meadow, which only yielded enough seed to do a third at a time. Now well established, this meadow contains a similar mixture of species to the parent meadow, although here the grass vetchling, Lathyrus nissiola, with its small solitary crimson pink flowers, was showing up well along the sides of the mown grass paths.

Part of the mature plantings originally acquired from the Harcourt estate was native woodland. This had been planted as a series of largely single species stands to create separate oak, lime and ash woodlands. Though 30 acres of the newly acquired land has been used to extend these woodlands, sadly an area of newly planted ash is highly vulnerable to the ash dieback fungus, Chalara fraxinea, that is sweeping across the country. Despite the young age of these plantings Alison was keen to show us two species of orchid that had become established - the spotted orchid, Dactyllorhiza fuchsia and a fine specimen of possibly Dactylorhiza majalis agg.

Our tour ended in the mature arboretum where Rhododendron and Cornus were providing splashes of colour amongst the magnificent mature pines, cedars, firs and redwoods. One pine tree in particular was taking advantage of the gusty wind to shed large clouds of pollen (pictured right).

Peter Grimbly

Plant of the Month

Galium tricornutum, corn cleavers, Rubiaceae

gallium 02 - photo by Alison Foster Galium is a cosmopolitan genus, of approximately 300 species of herbaceous plants. They typically have whorled leaves and leaflike stipules.

Corn cleavers, as its name might suggest, is an arable weed, a more diminutive sister species to the more familiar, widespread and much larger plant, cleavers (Galium aparine, goose-grass, pictured right).

Over recent decades, due to the changes in farming practice, arable weeds such as corn cleavers have come under significant threat of extinction. Corn cleavers, in particular, has been cited in the recent State of Nature report (a landmark report published by a coalition of 25 organisations, about the UK's wildlife) as an example of one of the most dramatic plant declines. Previously widespread, it is now reported to be found only at a single site in southern England.

However, the Rare Plants Group of the Ashmolean Natural History Society in collaboration with the University of Oxford Botanic Garden, are working to reintroduce this arable weed into a traditionally-farmed field close to Oxford, where it was previously recorded. We hope that the future is looking a little brighter for this species. More

Alison Foster
Oxford Botanic Garden

Medicinal Plant of the Month

Meliotus officinalis - photo by Kristian Peters Melilotus officinalis, yellow sweet clover, Fabaceae

What might yellow sweet clover (pictured right) and another species of Galium (Galium odoratum) have in common? The answer will be revealed in due course.

But first, we must go back almost 100 years to the 1920s and move across the Atlantic ocean to North America. Much like in recent years in the UK, there was a series of very wet summers in the 1920s in America and all the hay and forage crop being harvested was rotting and going mouldy. The farmers were desperate, and were still having to feed this spoiled crop to their cattle. However, the cattle began suffering from a bleeding disease and were haemorrhaging to death.

One day a desperate farmer took a bag of his mouldy hay and a container of blood from one of his dead cows in to a local research laboratory and asked the chemists there to investigate whether there was a connection between the two. He was convinced (and rightly so as it turned out) that something in the hay was causing the death of his cattle.

warfarin - formula Eventually, the chemists located a substance which they named dicoumarol in both the hay and the blood. Furthermore, they established that the dicoumarol was being formed in the mouldy hay from a substance called coumarin, that was present in some of the plant species in the hay. It is coumarin that is present in both yellow sweet clover and in sweet woodruff (Galium odoratum).

However, this doesn't make either of these plants 'medicinal'. After establishing that dicoumarol was an effective anti-coagulant, the scientists then went on to synthesise analogous compounds, with similar structures to dicoumarol, in an attempt to understand which part of the structure caused the anti-coagulant effect, as well as trying to make more effective compounds.

dicoumarol formation - formulae

Due to the perseverance of one particular student, a single analogue was then developed into the drug that today in the UK we know as warfarin. The research was funded by the Wisconsin Alumni Research Foundation (WARF). This drug, which is given to patients to control the clotting time of their blood, has saved countless lives after operations and also lives of people suffering from deep vein thrombosis. People often liken developing drugs to finding a needle in a haystack - and in this case it absolutely was!

Alison Foster
Oxford Botanic Garden

Horticulture Industry News

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Events Calendar

SCI Horticulture Group events are listed here

Other Events of Interest

Postharvest and Quality Management of Horticultural Products of Interest for Tropical Regions
1 - 5 Jul, International Society for Horticultural Science
Port of Spain, Trinidad

Fireblight
2 - 5 Jul, International Society for Horticultural Science
Zurich, Switzerland

Taxonomy of Cultivated Plants
15 - 19 Jul, International Society for Horticultural Science
Beijing, China

Pecans and Other Carya in Indigenous and Managed Systems
17 - 20 Jul, International Society for Horticultural Science
College Station, USA

Fruit for the Future
18 Jul, James Hutton Institute
Dundee, UK

Walnut Symposium
20 - 23 Jul, International Society for Horticultural Science
Taiyuan, China

Plant Bioregulators in Fruit Production
28 - 31 Jul, International Society for Horticultural Science
Orlando, USA

Jojoba world
30 - 31 July, Centre for Jatropha Promotion and Biodiesel
Jaipur, India

C4 and CAM Plant Biology
6 - 9 Aug, University of Illinois
Champaign, USA

Potatoes in Practice
8 Aug, James Hutton Institute
Dundee, UK

Photosynthesis: Opportunities and Challenges of the 21st Century
11 Aug, Hyatt Regency at the Arch
St Louis, USA

Plant Cryopreservation
11 - 14 Aug, International Society for Horticultural Science
Fort Collins, USA

Horticulture Economics, Marketing and Consumer Research
19 - 21 Aug, International Society for Horticultural Science
Portland, USA

Plantarium
21 - 24 Aug, Plantarium
Boskoop, The Netherlands

Rose Research and Cultivation
25 - 30 Aug, International Society for Horticultural Science
Hannover, Germany

Phylloxera
28 - 30 Aug, International Society for Horticultural Science
Bordeaux, France

EPSO Conference
1 - 4 Sept, European Plant Science Organisation
Port Heli, Greece

Managing Quality in Chains
2 - 5 Sep, International Society for Horticultural Science
Cranfield, UK

Tropical Horticulture
2 - 6 Sep, International Society for Horticultural Science
Santiago de Querétaro, México

Image Analysis Methods in the Plant Sciences
2 - 3 Sep, Nottingham University
Nottingham, UK

Fungal diseases, diagnostics and drug discovery
2 - 4 Sep, Society for General Microbiology (SGM) and British Society for Medical Mycology
Brighton, UK

Four Oaks Trade Show
3 - 4 Sep
Lower Withington, UK

Plum Pox Virus
3 - 6 Sep, International Society for Horticultural Science
Olomouc, Czech Republic

Agchem Forum
4 - 5 Sep, British Crop Production Council
Barcelona, Spain

Green viruses, from gene to landscape
7 - 11 Sep, EMBO
Hyères-les-Palmiers, France

Ornamentals in Africa
9 - 13 Sep, International Society for Horticultural Science
Naivasha, Kenya

Landscape and Urban Horticulture
12 - 14 Sep, International Society for Horticultural Science
Kolkata, India

Open Afternoon at Warwick Crop Centre
18 Sep, Warwick Crop Centre
Warwick, UK

Pomegranate and Minor Mediterranean Fruits
20 - 24 Sep, International Society for Horticultural Science
Taian, China

AgriGenomics
24 - 25 Sep, Select Biosciences
Norwich, UK

Knowing your enemy - the future of crop protection
5 Sep, HGCA
London, UK

International Advances in Plant Virology
25 - 27 Sep, Association of Applied Biologists
Norwich, UK

Sustainable intensification: The pathway to low carbon farming?
25 - 27 Sep
Edinburgh, UK

If you would like to advertise a forthcoming event please contact. ester.monfort@soci.org

Horticulture Group Contact Details

For submitting ideas or to volunteer to be part of a committee or a group, please contact:

Chairman - Peter Grimbly
Meetings Secretary - Alison Foster
Minutes Secretary - Margaret Waddy
Newsletter co-ordinator - Sue Grimbly scihortigroup@btinternet.com
Group Contact - Ester Monfort Martinez, E: ester.monfort@soci.org T: +44(0)20 7598 1584

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