Exploring the flora of Japan..

Gardens Curator Tom Price and Arboretum Curator Ben Jones have embarked on their four week field trip to Japan. This, the first of two trips, is part of a project to develop the living collections at the University of Oxford Botanic Garden and Harcourt Arboretum and the University of Oxford Herbaria. 

Japan is one of the 34 global biodiversity hotspots. Collectively these areas hold over 50% of all known plant species, yet cover only 2.3% of the Earth's land surface. The aim of this project is to cultivate plants from Japan at both the Botanic Garden and Harcourt Arboretum to communicate the importance of these biodiversity hotspots and the need for both in situ and ex situ conservation. 

The department is working in collaboration with the Department of Plant Sciences at Oxford, the University of Bonn Botanic Garden and botanic gardens across Japan.

This first trip involves travelling the length and breadth of Japan. From Hokkaido in the north to Shikoku in the south, via Tokyo, Niigata, Toyama and Kyoto. At each stop meetings are being held with botanic garden staff to establish seed collection sites of endemic plant species. These sites will be revisited in 2013 for the collection of seed and supporting herbarium specimens.

The Botanic Garden and Harcourt Arboretum are extremely grateful to the Impey family for their generous donation and to the Friends of the Botanic Garden and Harcourt Arboretum whose collective generosity has funded this trip.

Tom and Ben will be posting regular updates here on their progress over the next four weeks. Watch this space!

Naked Ladies Provide Gout Cure

The oncology bed of the Botanic Garden's medicinal plant collection has been glowing with colour in the autumn sun. The source of this radiance is the autumn crocus, Colchicum autumnale. Along with several other bulbs, its habit of flowering before the appearance of any foliage has earned it the common name 'Naked Ladies.' The mythical origin of this plant has it springing forth from drops of a magical potion concocted by the sorceress Medea to restore youth to Aeson. As this myth suggests, the medicinal properties of Colchicum have been known about for some time. In fact, it is first mentioned in the Ancient Egyptian Ebers Papyrus three and a half thousand years ago.

Colchicum autumnale  flowering on the oncology bed

The medicinal uses of this plant have not changed over the millennia- it is still used for the treatment of gout and joint pain. Modern medicine is researching its potential as an anti-cancer drug. As with many medicinal plants, the genus is extremely toxic and should never be confused, despite its common names, for the autumn-flowering Saffron Crocus, Crocus sativus. The stamens of the latter are an astronomically expensive condiment. In Crocus species there are only three stamens whereas Colchicum species have six.

Amaryllis belladonna

Amaryllis belladonna is flowering now on the family beds. In its native South Africa it is known as the March Lily, reflecting the Southern hemisphere month of its flowering. But the lack of accompanying foliage gives it another common name - 'Naked Ladies.' Now, it is worth pointing out that Amaryllis belladonna belongs to an entirely different family from Colchicum. Unlike Colchicum, it does not contain the active chemical Colchicine and has no application in the treatment of gout or in cancer research. This, of course, is an example of the confusion that scientific names were coined to avoid.

Umbel Relations

  Apiaceae, the carrot family, is well represented at the Botanic Garden. A huge family of annual, biennial and perennial plants with a global distribution, Apiaceae is characterised by its distinctive inflorescence - the umbel, which gave the family its former name of Umbelliferae. From familiar foods, such as carrot and parsnip, to the striking architecture of the ornamentals Eryngium and Bupleurum, to toxic and invasive weeds like Giant Hogweed(Heracleum mantegazzianum), the family is rich in variety and uses. 

Eryngium paniculatum on the Apiaceae bed

  Three species of Eryngium have germinated on the Merton borders with E. planum 'Blaukappe' producing spectacular, metallic blue inflorescences. E. maritimum, our native sea holly, has germinated well. Its thick, glaucous foliage can be seen dotted across the borders. The candied roots of this species were considered aphrodisiac in Elizabethan England.

Eryngium planum 'Blaukappe'

  Of the many Apiaceae species native to the British Isles several are threatened by changing patterns of land use. Sium latifolium, the Greater Water-parsnip, is a native plant found in the rafts of fen vegetation that build up on the margins of rivers and lakes. Modern approaches to the management of waterways have made such habitats increasingly rare. Now the Greater Water-parsnip is mostly confined to drainage ditches adjacent to arable land and is nationally scarce. The Oxford Rare Plants Group is active in the conservation of many threatened species in Oxfordshire including Sium latifolium. The Botanic Garden will be working with the Oxford Rare Plants Group to collect the seed of this plant for germination trials at the garden. More seed will be sent to the Millenium Seed Bank for long-term storage.

The nationally scarce Greater Water-parsnip
Sium latifolium

Braving the elements (in more ways than one)

As gardeners we are all used to dealing with "the elements"on a daily basis - braving whatever the weather throws at us. Never has this been more true than this year. However, at the University of Oxford Botanic Garden we are a positive lot and thought we'd embrace "the elements" - but in a different way altogether.

Following on from a successful collaboration with our colleagues in the Department of Chemistry (the other "Elements") in 2011 to celebrate International Year of Chemistry, we have teamed up once again to deliver a new audio trail entitled "Chemistry at the Garden" which is available free of charge to all our visitors. During the summer, a group of enthusiastic science communicators got together to record the audio trail on location at the Garden. Helped by the very patient Josh from the University podcast team, we told the stories of how plants have provided inspiration for chemistry research both in the past and still today.

The audio trail leads you around the Garden, where, at the appropriate places you trigger the sound by pointing the nib of the audio pen on a specially designed map. You can hear about photosynthesis, how the lotus plant has inspired the development of new materials, what makes the wonderful caramel smell that is wafting across the Botanic Garden on sunny days at this time of year and how the plants at the Garden helped an Oxford chemist win a Nobel prize.
Each of the trail stops lasts just a few minutes and gives you an insight into what motivates the research chemists to pursue their work.

The new audio trail was launched on the 13th September. The weather was kind and all those who came had fun exploring the collections with the audio trail. 

Another fantastic group who have braved "the elements" over the spring and summer are the volunteers who have been working at the Garden alongside our team of botanical horticulturalists. This year we have welcomed almost thirty gardeners and weeders who have enabled us to tame the weeds in the face of one of the wettest summers on record. Their help has been invaluable in keeping our worst weed (Nothoscordum) under control and their never ending enthusiasm to eradicate this beast is much appreciated. On Wednesday this week we said a proper thank you to all our volunteers (whether office based or practical, Garden or Arboretum) as well as all those who have given their time to support the Friends of the Botanic Garden and Harcourt Arboretum over the past year. This occasion was marked  of course by tea and cake (and more cake).

After consuming our bodyweight in cake we finished with a walk around the Botanic Garden, led by Gardens curator Tom Price.

It seemed only appropriate that is was pouring with rain!

Keys at the Sea

The Botanic Garden is a living collection of plants and, like any museum collection, it is important to know exactly what we are looking at. Plants can be identified in a number of ways- often it is enough to see a plant once and be told what it is to establish familiarity for life. Often it is possible to match the living plant to a picture or photograph in a guide. An image search on the internet, however, may provide us with a variety of plants from widely different families, all sharing the same name. It is obvious that identification has to come from an authoritative source. Luckily for botanists and gardeners this source exists in the form of comprehensive floras of native and garden plants. It was to gain experience in using these guides that staff from the Garden team attended a recent course in identifying coastal plants run by the Field Studies Council.

Saltmarsh at Shingle Street, Suffolk

Which Salicornia is which? 

The course took place in Suffolk under the expert tuition of Ros Bennett. Staff from the Botanic Garden joined other students in an effort to identify various coastal plants, mainly using the key from Stace's New Flora of the British Isles. A key of this kind lets the user choose between two descriptions of a plant. The chosen description will lead to another pair of descriptions, and so on, until the plant has been identified to the level of family, genus or species. Often the key features in these descriptions require a hand lens to be visible. The curious naturalist discovers a hidden world of microscopic beauty. 

Many beautiful plants grow in the ever-changing landscape of the salt marshes and shingle. Obviously, many are adapted to the high levels of salt and the regularly inundated mud of estuaries. While these plants may be impossible to grow in Oxford some, such as Sea Lavender (Limonium) and Sea Kale (Crambe maritima) are thriving in the garden.

In any case, learning how to use a flora allows us to identify plants from any habitat and encourages to look at the wonderful variety of detail that makes every plant species unique.

Keeping it in the family...

Towards the end of summer there is one plant family above all others that provides the final foray of colour, the daisy family: Asteraceae.

There are c. 27,000 species in this family assigned to 1,765 genera, making it one of the largest plant families. The diversity of this group is pretty staggering, with representatives found worldwide, only absent from the Antarctic mainland.  From annual herbs and arctic alpines to the narrowly endemic and threatened, arborescent Dendroceris of Chile.

We represent a reasonable amount of this diversity at the Botanic Garden, both in the Glasshouses and the Gardens. Here are a few:

Rudbeckia maxima

Rudbeckia maxima from the central and southern USA is a fine garden plant. It grows to about 1.8m, has sumptuous, glaucous, ornamental leaves and does not need staking. Grown as a repeated element through plantings it provides a very natural effect.

Dahlia 'Moonfire'

The Dahlias are now in full bloom, somewhat delayed by the weather. We cultivate a large number of cultivars at the Garden, mostly within the Autumn   Border. These are bedded out each June, following on from the spring flowering tulips and forget-me-nots. They are then lifted in late October and the tubers protected over winter in deep frames in the nursery. The best of the bunch include: 'David Howard', 'Moonfire' (right), 'Grenadier', 'Twinings White Chocolate' and 'Dovegrove'.

Bartlettina sordida

The Glasshouses hold a range of interesting species. Including the spiny shrub Barnedesia caryophylla from South America, Bartlettena sordida (left) from Mexico, which is vaguely reminiscent of Eupatorium and the endangered Centaurea akamantis from Cyprus.

Centaurea akamantis

As well as all these striking ornamental members of the family, it's also worth mentioning that many of them are familiar and important food crops. Both kinds of artichoke, Jerusalem (Helianthus tuberosus) and Globe (Cynara cardunculus var. scolymus) are in this family. The former has edible tubers containing inulin, broken down by bacteria in our large intestines yielding the familiar and rather antisocial side effects of eating these tubers!

Globe artichoke

Pop into the Botanic Garden over the next few weeks to see this family at its best.

Plotting on...

This year's curious weather has not been too kind to the vegetable plot. Unseasonal warmth and drought followed by months of cold rain... Most vegetables are annuals or are at least grown as such, and they need good conditions to establish themselves. Bad weather at the wrong moment can set crops back to the extent that they never really establish well. Perennials, on the other hand, can endure difficult conditions and even thrive in them- our rhubarb is a good example.

Courgette and sweetcorn bulking up.

Broccoli 'Beaumont'

Nevertheless, the vegetable plots  are producing. Last week the first brassicas were ready: cauliflower, calabrese and 'Hispi' cabbage were all harvested by Oxford Food Bank as part of their weekly collection. Courgettes, which had refused to grow in the cooler temperatures, finally began to bear fruit and the first french beans developed from the subtle pink flowers of 'Cobra'.

         Climbing French Bean 'Cobra'
   

It has been exciting to watch the onions bulking up since the days began to shorten after the summer solstice. This decrease in daylight length is the trigger for seed-grown onions to put all their growth into bulb formation. We sowed pinches of onion seed in modules at the beginning of february and planted out the whole modules. As they have grown the onions have just pushed each other apart. The drooping, yellowing tops are a sign that they will soon be ready to harvest!

Onion 'Ailsa Craig'

We have had to wait longer than expected for the potatoes to reach a worthwhile size- 'British Queen' is a second early and 'Anya' is grown as a maincrop, we get good results from harvesting it earlier and although the potatoes are smaller we can usually harvest before blight affects the plants. This year the humid conditions have caused some blight- in an attempt to save the crop we have removed all the foliage to ground level to avoid spores being washed off the foliage into the ground. So far, so good...

'British Queen' before losing her foliage to blight.