Researchers at Plantlife would like your help in collecting information on the native bluebell which is threatened by the Spanish bluebell, writes ELIZABETH EDWARDS

The bluebell is the nation's favourite flower but there are questions as to just how many of the plants we see in bloom at this time of the year are the native species. Plantlife, the international charity dedicated to the conservation of wild plants in their native habitats, together with the Natural History Museum in London, the Royal Botanic Garden in Edinburgh and the Ramblers' Association, have been investigating to what extent our native bluebell, Hyacinthoides non-scripta, is being threatened by the invasions of the Spanish bluebell, Hyacinthoides hispanica (See Flora of Oxfordshire, left), which is often planted in gardens and the hybrid Hyacinthoides hispanica x non-scripta.

Bluebells for Britain was launched to alert the public to these potential threats and, with bluebell-time upon us, information that would help the research effort would be welcomed.

People out walking in woodlands can take this opportunity to look closely at the bluebells they see.

In Oxfordshire, there will be a number of opportunities on organised walks.

At opposite ends of the county, in the west there will be a Bluebell Walk for charity at the woodlands at Badbury Hill, near the National Trust estates at Coleshill, near Faringdon, on Sunday, April 20, starting at 10.30am and, in the east, a Bluebell Walk, also for charity, on the National Nature Reserve at Aston Rowant, will be an opportunity to see our native bluebells in an area in which they are being conserved. This walk sets off at 1pm.

The native bluebell, in Scotland also known as the wild hyacinth, is a bulbous perennial. Our indigenous species is native to north-western Europe, where it seems to prefer slightly acidic soils and partial shade.

Early in the growing season, it can be a dominant species in coppiced woods on light soil but is also found on hedge-banks. The native bluebell's deep violet-blue flowers have a strong sweet scent and the flower stems droop or nod distinctively to one side.

The Spanish bluebell is native to Portugal and western Spain and was introduced into British gardens in the 1660s as an ornamental plant. It was favoured over the native species because it can grow almost anywhere and has bolder blooms.

It is a more upright plant than the native bluebell. Its flowers range in colour from pale to mid-blue and it can also be white or pink but it has characteristically deep-blue pollen. It has very little, or no scent.

The Spanish bluebell was first recorded in the wild in Britain in 1909.

The hybrid bluebell has become prevalent because the native and Spanish varieties can readily cross-breed from this fully-fertile hybrid.

It was first recorded in the wild comparatively recently in 1963. It is mainly found in woodlands but also grows in hedgerows and churchyards, by shady roadsides, on rough ground and in waste places and it has become extremely common in gardens.

Jayne Manley, Plantlife's director for development and communications, points out that the threat to the native bluebell has a wider aspect, for research by the Natural History Museum suggests that it is not as widely distributed in Europe as had been thought and therefore the populations in the UK have been shown to be of world importance. They represent half the total numbers.

The deep-blue native plant has been present in Britain since the Ice Age and held sway until the arrival of the newcomers.

Scientists at the Natural History Museum and at the Royal Botanic Garden in Edinburgh have been using the most up-to-date genetic techniques to trace the family history of the bluebell. Further findings this spring will help to confirm those from the earlier years of the survey.

Bluebells are a protected species, making collection from the wild for commercial purposes illegal. Collection of any wildflower is also illegal without the permission of the landowner. Unfortunately, the demand for native bluebells has led to illegal collection. There have been a number of successful prosecutions for the uprooting of bluebells without a licence.

The threat to the overall population underlines an international obligation to protect the native population in Britain. There are other threats - habitat loss, due to poor management or to the conversion of woodland to farming, and climate change.

Encouragingly, the majority of records received from the surveys in previous years were of the pure native bluebell populations still to be found in woodland strongholds. However, one in six of these woodlands had a mixture of species, with one or both of the others also present.

Plantlife points out that the presence of hybrids on road verges in built-up areas points to the fact that the Spanish or hybrid species are present in local gardens.

Gardeners can help by not planting these two foreigners. When buying, they should check the scientific name when selecting bulbs and also check that they have not been sourced illegally, nor incorrectly labelled. Information on the packaging as to origin should be checked and suppliers asked for their policy on obtaining supplies.

Anybody who would like a survey form can contact Plantlife on 01722 342730 or the Natural History Museum at nhm.ac.uk/bluebells.

Bluebell walks

Natural England and the Lewknor Gateway Project have organised a bluebell walk at Aston Rowant nature reserve on Sunday, April 27, 1-3pm. The event is free. It is followed by tea and cake from 3pm. Meet at the reserve car park signposted from the A40 near Stokenchurch.

Alternatively, you can try the walk for charity at Badbury Hill, near the National Trust estates at Coleshill, near Faringdon, on Sunday, starting at 10.30am.

Canine Partners have also organised Bluebell Walks throughout this month and next. The charity specialises in providing highly trained assistance dogs to people with disabilities. Canine Partners is looking for walk organisers that want to set up an event in their area as a way to raise funds for Canine Partners, as well as participating in a fun and healthy day out for all the family.

A walk can be for five to 100 people, covering distances from a mile to ten miles. Organisers will be sent a free information pack.

Visit their website www.caninepartners.co.uk or call Malcolm Wells on 01730 716011 or Jane Bryant on 01730 716013 for further information.