Bluebells - By Gillian
The British bluebell Hyacinthoides non-scripta is the most recognisable and best loved of our (British)spring flowers. It is particularly associated with ancient woodland, dominating the understory to produce carpets of bluish-purple flowers in "bluebell woods". However, this most characteristic of British plants has been the subject of growing concern as its survival is threatened.
Experts have warned that this wild flower could be wiped out by a similar Spanish variety. The Spanish bluebell Hyaointhoides hispanica which is scentless and paler than its British cousin was introduced to British gardens many years ago. This foreign ‘invader’, is increasingly cross-pollinating with the home-grown strain, creating a new hybrid. Both non-native flowers are now becoming more common in parks, gardens and garden centres. Cultivars of the Spanish bluebell are now more commonly grown in British gardens than the British bluebell.
The Suffolk Wildlife Trust argues that hybridisation can alter the genetic make-up of a species. They propose that gardeners should not plant Spanish or hybrid bluebells since they threated the long term survival of the native populations. They claim that hybrid forms could potentially oust the natives, eventually leading to the whole bluebell woods vanishing. This could also impact negatively on other wildlife as bluebells provide important food for bees and butterflies.
Our Investigation.
In light of this, Haley and I conducted investigations to determine if the Spanish Bluebells have encroached in Seeley Copse. We started our observations just past the gate and observed patches of bluebells in a systematic method, using a large grid so as not to cause any damage to existing blooms. We looked at the shape of the flower and colour of the anthers to decide if the bluebells were Spanish or British. According to the National History Museum, the easiest way to tell the difference between native and non-native bluebells is to look at the colour of the pollen. If it is creamy-white then the bluebell is a native. If it is any other colour, such as pale green or blue, then it is definitely not native.
The difference between English and Spanish Bluebells.
English bluebell - Flowers of native bluebells are narrowly bell-shaped, with straight-sided petals, deeply curled back at the tips. The majority of flowers droop from one side of the stem. The anthers are creamy-white and the leaves narrow, usually between 0.7-1.5cm wide (about ¼-¾in), although occasionally up to 2cm (¾in). These native flowers also have a strong, sweet smell.
British Bluebells
Spanish bluebell and hybrid - The bell-shaped flowers of Spanish bluebells and the hybrids between this and the English (known as H. × massartiana) open more widely than on English bluebells, with the petal tips just flaring outwards or curling back only slightly. Some flowers may droop from one side, but most are arranged all around the stem and held more erect. The anthers of Spanish and hybrid bluebells are usually pale to dark blue, and the leaves are wider, up to 3-3.5cm (about 1¼in) across.
Spanish Bluebells
Our results-
No Spanish bluebells were detected in the areas examined.
Conclusion.
Based on our observations we can suggest that Spanish bluebells are not present in the areas examined. Further investigations will be needed, covering a greater surface area of the woods ( particularly near to the bordersor periphery of the woods, near the Houses/ gardens) in order to determine if there is the presence of Spanish Bluebells in Seeley Copse.
Based on our observations we can suggest that Spanish bluebells are not present in the areas examined. Further investigations will be needed, covering a greater surface area of the woods ( particularly near to the bordersor periphery of the woods, near the Houses/ gardens) in order to determine if there is the presence of Spanish Bluebells in Seeley Copse.
Spanish Bluebells have been found in other woods. Why is this?
Spanish bluebells are mainly found in the vicinity of villages, towns and cities. They are common in churchyards, cemeteries, hotel gardens, parks and gardens. It has been reported that many bluebell bulbs sold by some garden centres and commercial suppliers are called ‘British native bluebells’ when, in fact, they are Spanish. They also occur as either escapes or "throw-outs" alongside road-verges, wastelands, hedgerows and woodland borders. When garden waste is fly-tipped in the countryside, the Spanish bluebells become established, interbreeding with the native British bluebells. When this happens, because its genes are dominant, the traits of the British bluebell disappear within a very few generations. It has been found that in certain cases, Spanish bluebells have been found because of well-meaning people actually planting bulbs of the Spanish bluebell in the woods!
So Where have these Spanish Bluebells come from?
Records show that cross pollination between the native and Spanish flower - introduced about 50 years ago because people wanted bluebells in their gardens - had created a hybrid, leading to the decline of the pure native flower. The Spanish bluebell has been planted in gardens for many years because it is easier to grow than our native British bluebell. The British bluebell is very particular about where it grows because it is dependent upon a specific fungal environment (Mycorrhizal fungi) generated from rotting leaf-matter. Without the assistance of the fungus, the native bluebell cannot synthesise the nutrients necessary for growth. To grow Spanish bluebells represents more of a threat to the survival of the native form than digging it up in the wild, because, without the fungus Mycorrhiza, the transplanted bluebell will die.
Why is this a problem?
Conservationists say the native flower could be wiped out by its hardier Spanish cousin, which is rapidly taking over our woodlands. It has been found that the Spanish bluebells have started creeping out of flowerbeds and into woods and forests where they have crossbred with the native variety. In some areas of the woods, the Spanish bluebell is already dominant. They are taking space and nutrients from the native bluebells and also cross pollinating with them creating a hybrid bluebell. Studies have shown that one in six woodland areas is now home to a mixture of native, Spanish and hybrid bluebells. The threat is so great that the Natural History Museum has started a nationwide survey to establish the spread of the foreign interloper. Bluebells can spread rapidly, sending out underground runners, on the end of which new bulbs form. They also seed freely and often hybridize when grown together. In light of this, conservationists have predicted that the continuing genetic purity of the surviving fragmented H. non-scripta populations is unlikely especially in urban areas and they will be replaced by the aggressive Spanish invader. The Devon Wildlife Trust says the problem is so widespread that the pure-bred British bluebell could be wiped out within ten years.
On the other hand, some researchers have argued that in survival terms the hybrid has the edge as more genetic variety is known to help species survive change.
What can we do to protect our British Bluebells?
Education is necessary to slow the spread of H. hispanica genes. It is important to never plant anything from your garden in parks or in woods. Proper disposal of garden waste, not into rural areas adjacent to woodlands can help to slow the spread of Spanish bluebells as well. Any ‘invaders’ should be placed in black plastic sacks and left for a year before composting. It is important to remember that it is only legal to dig up wild plants on your own land!
The Wildlife Trusts is urging gardeners who live near woodlands to shun the Spanish bluebell, in favour of the traditional British variety. Gardeners should also ensure they buy native varieties rather than hybrids -- and never dig up the plants from the wild. The native bluebell is protected under the Wildlife and Countryside Act and so it is illegal to dig up wild bluebells! Anyone caught uprooting plants or digging up bulbs can be fined £2,500!
References:
Kohn, D., Hulme, P., Hollingsworth, P., Butler, A. (2009) 'Are native bluebells (Hyacinthoides non-scripta) at risk from alien congenerics? Evidence from distributions and co-occurrence in Scotland', Biological Conservation, 142, 1, [Online.] Available at: http://www.sciencedirect.com/science/article/pii/S0006320708003686 (Accessed: 7 April 2012)
Linconshire Echo (2009)'Bluebells blossom despite triple threat', 15 April, [Online]. Available at: http://ebscohost/ (Accessed : 10 April 2012).
Mabey, R (1996) Flora Britannica:The Definitive Guide to Wild Flowers, Plant and Trees. London: Sinclair and Stevenson.
MacRae, F. (2006) 'BRITISH BLUEBELL 'WILL BE WIPED OUT IN TEN YEARS'', Daily Mail, 27 April, [Online]. Available at: http://ebscohost (Accesed :9 April 2012).
MacRae, F. (2006) 'BRITISH BLUEBELL 'WILL BE WIPED OUT IN TEN YEARS'', Daily Mail, 27 April, [Online]. Available at: http://ebscohost (Accesed :9 April 2012).
National History Museum. http://www.nhm.ac.uk/nature-online/species-of-the-day/biodiversity/endangered-species/hyacinthoides-non-scripta/index.html
Pilgrim, E and Hutchinson, N. (2003) Bluebells for Britain- A report on the 2003 Bluebells for Britain survey. [Online] Available at: http://www.plantlife.org.uk/uploads/documents/People-and-plants-mapping-the-UKs-flora.pdf (Accessed 9 April 2012).
The Times (2010) 'Spanish invader' April 4 [Online]. Available at: http://ebscohost
Western Morning News (2006), 'Bluebells at the mercy of Spanish invaders', 28 April [Online]. Available at: http://ebscohost (Accessed: 13 April 2012).
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