England's bluebells fight for their lives !

[Dave]

BRITAIN'S native BLUEBELLS
The battle for survival,


Britain's native bluebells are under threat from an aggressive hybrid,
so could they disappear completely?
The bluebell is a quintessential sign of British springtime,
with the vast spreads of tiny blue flowers found across Britain in April and May.
In fact, the UK's woodlands are home to almost 50% of the global population of our native bluebell (Hyacinthoides non-scripta). With its unique scent and the very delicate form and structure of the flowers, it is an extremely special flower.

But our native bluebell is now under threat from an aggressive hybrid. And with the UK being home to such a large chunk of the world's population, it means this bluebell is threatened on a global scale. It's ringing alarm bells for conservationists.
Many of the bluebells found in our gardens and urban areas are not the traditional British flower,
they are in fact an aggressive hybrid (Hyacinthoides x massartiana) - the product of cross-breeding between the native bluebell and the Spanish variety (Hyacinthoides hispanica).
This hybrid was first recorded in the wild in 1963. It's highly fertile and has spread rapidly in the UK's urban areas.
But more worryingly, its distribution has also been increasing in woodland areas - the preferred habitat of the UK's native bluebell and home to some of its oldest populations.
Evidence shows that when a hybrid bluebell has got into a woodland area it does have the ability to take over,
There are concerns that hybridisation could dilute the distinctive traits of our native bluebell over time.
To make matters more complicated, identifying the hybrid in order to assess its rapid spread is no simple matter.
When identifying bluebells, it is important to look at flowers that have just opened. Older flower spikes are less unidirectional and more upright. Also pollen may be lost and the flowers could have lost their scent.
Know your bluebells   
Bluebell type    Characteristics

Native bluebell (Hyacinthoides non-scripta)   Flowers have a strong, sweet scent
Pollen is creamy-white
Flower stems nod to one side
Deep violet-blue in colour
Often found in woodlands or shady areas

Spanish bluebell (Hyacinthoides hispanica)   Native to Portugal and western Spain
Pollen is deep blue
More upright than native plants
Flowers can be pale to mid blue, white or pink
Grown in gardens and found in the countryside

Hybrid bluebell (Hyacinthoides x massartiana)   Flowers range from dark to pale blue, pink and white
A hybrid of native and Spanish bluebells
Can show characteristics of both parent plants
Widespread in urban areas; has been recorded broad leaf woodland
Thought to be more common than the Spanish variety

The hybrids are incredibly variable, which makes identifying them difficult.
Some hybrids will be almost identical to the Spanish plant, while others are almost identical to the native.
Sometimes you cannot tell the difference unless you apply DNA analysis.
Although they may still outnumber non-natives by 100 to 1, the possible scale of eventual change in native populations should not be underestimated.
native and non-native bluebells were planted together in recent research experiments.
reseachers found that in just three years the non-natives had reproduced at a much greater rate than the natives had.
So could this spell the end of the British bluebell?
There are certain areas in southeast England where the bluebell will become a somewhat different plant to what it was several hundred years ago.
There's even evidence that this is already happening. In London for example, nearly all plants will have varying degrees of mixture with the Spanish bluebell.
But researchers do not think it's a "death knell" for our native bluebell, but spreads in ancient woodland could change irreversibly

Effectively as gardeners in the last 200 years we've undone 8-10,000 years of isolation by bringing together the Spanish bluebells with our native species.
What we have done may cause irrevocable change to a species for which we hold the major proportion of examples in the world.
We should therefore act as we directly caused the problem.
What could help stop the spread of the aggressive hybrids is milder weather.
I think this early milder weather might separate out the flowering times of the native and hybrid bluebells. At the moment they overlap completely and can only hybridise when the flowering in synchronous.
But if this strange weather means that they overlap less, then it would reduce the chance of them hybridising.
The National Trust reports that bluebells are likely to peak in time for the Easter weekend across most of the UK, earlier than previous years.
The low winter rainfall also means bluebells could be smaller and less abundant in 2012, but the dry conditions could mean the ones that do emerge will be well-scented.

Thanks to GG