The last week in April and the first week in May are usually the best times for Bluebells. These stunning, violet-blue relatives of the Hyacinth are mainly associated with deciduous woodlands but are also found growing in open land and underneath bracken; occasionally white or pink flowers occur. They have a strong, sweet scent, especially on warm days, and are very attractive to pollinating insects; bees will sometimes bite a hole in the top of a bell to reach the nectar. A close relative, the Spanish Bluebell, is paler in colour and has flowers on all sides of the stalk, whereas the English variety bears its arching, drooping blooms on one side only. They can cross breed and will produce fertile offspring which has caused a worry that our native flower may be overtaken by these hybrids. The bluebell is a protected species and it is illegal to pick the flowers or dig up the bulbs and if you disobey the law, legend says that the fairies will take their revenge and we know what they can be like!
Red Campion has started to bloom and often coincides with Bluebells making a colourful spring display. This pretty rose-red flower grows on grassy banks, in hedgerows and woodlands and has separate male and female plants. If it is growing near White Campion they often hybridise, producing pale pink flowers. Since the 1930s 97% of our native wild flowers have disappeared taking a lot of colour from our lives and affecting our wildlife, especially insects. BBC Countryfile has teamed up with ‘Grow wild’, led by the Royal Botanic Gardens, Kew, to encourage people to help the situation. They are giving away free packets of seeds for planting on spare ground and in our gardens. A small area or even a pot will help and you can obtain your seeds by going to https://www.growwild.com/ or by contacting Kew Gardens directly. Last year they ran out fairly quickly so if you are not lucky many garden centres also sell them.
As well as flowers on the ground there are many above our heads this month. Trees are in blossom and one of the most dramatic is the Horse Chestnut which has flowers arranged to form large pyramids, often called candles, most commonly white but there is also a red variety. Horse Chestnuts are long-living trees, but are affected by several diseases caused by fungi, bacteria, scale insects and a leaf mining moth whose caterpillars chomp their way through the leaves. One of the most serious, known as bleeding canker, can result in the death of these trees and was previously caused mainly by fungal infections. There was a sudden upsurge of this disease, which causes the bark to ooze dark, sticky liquid, around 2007 when a newly arrived bacterium affected many more trees than before. Unfortunately, as yet, there is no cure available and badly affected trees are felled and burned.
The Oak is another tree affected by bleeding and this can be caused by fungi, bacteria or possibly a beetle which has been found around lesions on the trunks. The disease can result in death, which is worrying because the Oak tree supports more forms of life than any other in British forests. Besides mammals and birds it is also home for hundreds of species of insect, one of which we may never see. You will have seen the fruit-like bodies, which we call oak apples, that appear to grow from the stems of oaks. As children my sisters and I would sample anything that sounded remotely like food and they most definitely are not apples! In our ‘testing’ we may well have unknowingly consumed some protein in the form of the small larvae that live in the middle of this apple, which is in fact a gall; the larvae are the young of an Oak gall wasp. This insect has an interesting life cycle with two different generations. The wasps that emerge in the summer are both male and female and after mating the female lays her eggs on the roots of the tree where the hatching larvae will feed. In late winter or early spring these all emerge as females and they are able to produce eggs without the help of a male. This generation inserts the eggs into the developing buds and the tree reacts to this intrusion by forming a gall. It is thought that the hatching larvae secrete a chemical which causes the tree to do this, providing themselves with food and shelter until they pupate. When summer comes the adult wasps emerge through tiny holes, which they drill in the gall, and start the cycle all over again. May 29th is ‘Oak Apple Day’ and commemorates the restoration of the English monarchy when Charles ll returned from exile in 1660. He is reputed to have hidden in an oak tree, before he escaped to the continent, when eluding Oliver Cromwell’s soldiers. The 29th was his birthday and people used to wear oak apples or leaves in his honour.
There are many types of oak gall wasps which lay their eggs on different parts of the tree. Leaves, buds and acorns are all affected and not all the larvae are safe inside their galls. As well as being eaten by inquisitive children there are other wasps which lay their eggs into the gall and, depending on the species, their larvae will either also feed on the gall or on the resident larvae.
Our Norfolk wetlands provide an ideal habitat for many species of water dwelling birds including waders, ducks and geese. The most common goose in Britain is the Greylag, which is also the largest and heaviest. This browny-grey bird is very distinctive with pink legs and an orange beak and is the main ancestor of domestic geese. Historically they were quite widespread in Britain but became restricted to the far north and west of Scotland by the early 1900s, mainly due to persecution by shooting. The countrywide population was re-established from eggs taken from the Scottish nests and is now widespread wherever there are watery places and arable or pasture land. Flocks of Greylags announce their arrival on farmland with honking cries as they descend to feed on spilt grain, sugar beet, new shoots and grass; large numbers can cause crop damage and reduced yields. They are nesting, now, in marshes and Broadland reserves and will sometimes be in gravel pits at this time of year.
Butterflies are in flight on sunny days; one is the pretty Common blue which inhabits meadows and sometimes gardens. The caterpillars feed on legume plants, especially clover, vetches and trefoil. If you are in Holt Country Park this spring you may be fortunate to see the Yellow-legged Tortoiseshell. This species is native to Eastern Europe, Japan and China and had not been seen in Britain for around fifty years until last summer. It was thought that they would not survive the winter here but the early sighting of the one at Holt almost certainly means that it hibernated successfully.
Some dragonflies are also flying this month having emerged from the water where they spent their larval days and the first we may see are the damselflies. They are smaller than the true dragonflies, are often brightly coloured and, unlike their larger relatives, hold their wings folded over their bodies when at rest.
Things to do this month include:
- A visit to Weeting Heath.
- Bluebell walks at Lower Wood, Ashwellthorpe and Foxley Wood.
- Earth walk for children – Cley marshes.
- Breeding birds – Cley Marshes.
- Details at www.norfolkwildlifetrust.org.uk or 01603 625540.
- Dawn chorus walk – Titchwell Nature Reserve – 01485 210779.
© Sheila Sims 2015. Email: firstname.lastname@example.org