As the Bluebell extravaganza in Wivenhoe Wood starts to fade, I have been reflecting on the wonder that is our Bluebell. An almost universally-loved feature of our spring countryside, but one that is if anything underappreciated. It is a feature of the here and now: here, as it is restricted to the Atlantic fringes of northern Europe; now, as in the past when we still had Wild Boar, their rootlings would have prevented the massed displays we now take for granted.

Native Bluebell

Spanish Bluebell

But as is well known, our native Bluebells are under threat, particularly from the Spanish Bluebell, not by displacement but by dilution – insidious genetic pollution. The Spanish species, grown in gardens here for a couple of centuries at least, is less vibrantly coloured, more feebly scented, with splayed rather than recurved petals, altogether a less droopingly delicate plant, with flowers all around its stems, rather than one-sided. Unfortunately, as plants so often do, the two species readily hybridise. And the hybrids breed freely with other hybrids or either parental species. The result? A continuous suite of intermediates between the two parental species. 

Sometimes those hybrid intermediates are quite clearly so…

Hybrid Bluebell

…but sometimes less clearly, in which case you need to look more closely at the flower structure, as I have been doing this week. 

To be a true native Bluebell, the ‘petals’ (actually technically termed tepals, as the six segments representing the sepals and the petals are the same shape and colour as each other) should be strongly recurved; the pollen-producing anthers should be cream in colour; and the stamen adjacent to each outer tepal should be fused to the surface of the tepal for at least 75% of its length. Incidentally, all this came as a surprise to me as a lifelong botanist: I had simply never delved into bluebell flower structure before. Never knew about the stamens fused to the tepals, nor the fact that the stamens associated with the inner whorl of tepals are shorter, attached only at the bottom of the tepal, and the inner anthers burst open to release pollen later than the outer anthers. Such a revelation!

Above: close-ups of a native Bluebell flower

In contrast, ‘good’ Spanish Bluebells should have splayed tepals; blue anthers; and the stamen adjacent to each outer tepal should be fused to the surface of the tepal for less than 75% of its length.

Above: Close-ups of Spanish Bluebell flower

And then there are the hybrids, intermediate in detailed flower features as well as gross morphology.

Above: close-ups of Hybrid Bluebell

Trouble is that whereas plants may look either of the true parental species, detailed examination of anther colour and stamen insertion etc often reveals a degree of hybrid ancestry, anomalous features which indicate genetic pollution through the pollen dispersal activities of bees. The closer one looks, the less clear-cut the story becomes!

Not so long ago, we were in the grip of cold, damp weather which had set back the onset of Spring by two weeks or more. But now, in response to recent unseasonable warmth, it feels like it is racing to catch up and make up for lost time. Swifts have been scything the airwaves over the town for three days already, three weeks ahead of schedule…

In Wivenhoe Wood, the Wood Anemones, just opening a fortnight ago and which often retain the power of their display for a month, are already past their best. The snowflake blanket  of Anemones and Blackthorn is beginning to look ragged, and other white delights are starting to fill the gaps – witness the creeping patches of Greater Stitchwort and, more sparingly, Barren Strawberry, its petals so well-separated that the green sepals show through. ‘Barren’ because it fruits are hard, not the succulent red flavour bombs of Wild Strawberry, whose flowers are yet to show.

Lifting the colour into the canopy, the large white clusters of Wild Cherry flowers provide a counterpoint to the dangly, insignificant catkins of English Oak.

And other hues are being added to the woodland palette, especially the intense, fragrant blue of Bluebells, now approaching their peak, on time if not a shade early: spring has been telescoped into a few frantic days. Catch them if you can, especially on a still, sunny morning when the fugitive, heady scent is almost intoxicating. Then waiting in the wings are the reds (Campion) and yellows (Archangel), buds straining to sprinkle their pointillistic colour on the pastel background, before the ferny foliage of Cow Parsley masks it with emerald-green, and the leaves of the tree canopy expand fully, marking the arrival of summer.

On the edge of the wood, and out into Lower Lodge meadows, the yellow is already here. Broom buds have burst, and the grass is studded with the nectar- and pollen-filled sunbursts of Dandelions in flower. A beacon for all manner of insects, they offer their bounty to all, unlike the Red and White Dead-nettles whose two-lipped flowers restrict their bounty to insects of a certain size, which are heavy enough to open the mouth of the flower when they land on the lower lip. The importance of Dandelions in particular is such that it justifies leaving the lawnmower alone for a few weeks yet.

Where springs merge at the foot of the slope, Cuckoo-flower is now blooming, pale pink, sometimes almost homeopathically-so. And just in time: the first Cuckoos are now calling, and the first Orange-tips are on the wing. Whereas the link between Cuckoo and Cuckoo-flower is merely one of temporal coincidence. the butterfly has a more pressing biological link, often laying is eggs on the stalks of the flower. Such are the complexities of Nature’s calendar: beautiful, the fruits of eons of evolution, but sadly all too likely to be thrown out of kilter by climate change.

My previous post took a look at some of the showier flowers appearing around Wivenhoe right now. But there are others, less showy and more of an acquired taste perhaps: the ‘little white jobs’, of which there are many in our gardens and waysides.

Several of these are in one family – the Brassicaceae, or cabbage family – and easily recognised as such by their flower structure, usually having four petals and sepals, six stamens (male naughty bits), and a single female part (style) in the centre. After that, the separation into species is best done by looking at the distinctive fruits and seed pods, which in the annuals below are produced only a very short time after the first flowers.

Shepherd’s-purse (above) is so-called because of the lobed, almost heart-shaped seed pods.

In contrast, Hairy Bittercress has long, thin, upright seed pods, the tips of the pods projecting above the flowers and so distinguishing from other Bittercresses.

 And smallest of all, Common Whitlow-grass, barely 6cm tall usually, and found especially where the soil is on the sandy side. Definitely worth adopting the Botanist’s Pose for, nose to the ground and bum in the air, check out its petals, each deeply divided into two lobes, its pointed oval pods, and then its leaves covered in whitish, branched hairs – just click on the right-hand photo above to get a closer look.

Finally for now, one further species which may look similar, but is soon revealed to be in a different family altogether. The Caryophyllaceae (campion family) generally have five sepals and petals; five to ten stamens, and three to five styles. Common Chickweed (below) shows this well, especially the five petals, again divided to the base, and so looking like ten; and three female styles, each bearing a pollen-receptive stigma.

Yes, Spring is here. Nothing can stop it now, surely…. Each day, new flowers are blooming, new insects are stirring, new birds are singing, including Chiffchaffs and Blackcaps, mostly just arrived from their wintering grounds, and merging seamlessly with the swelling voices of our resident songsters.

True Blackthorn in the hedges, leaves only just showing, if at all,  as the flowers open, Green Alkanet and Lesser Celandines have large open flowers, available to all insects.

In contrast, tubular flowers such as Red and White Dead-nettles restrict access to their precious nectar resources to the largest, heaviest, long-tongued insects – be more selective, and you maximise the chance of pollination with the right sort of pollen. And then there are the gems, tiny flowers such as Ivy-leaved Speedwell, which are such a morsel as to be of interest only to the smallest flies and wasps.

Many of the newly-emerged flowers are rather showy, and have to be if they want to attract appropriate pollinators. All it takes is for the sun to go in, or an easterly breeze to kick in, and temperatures stall, such that insect activity grinds to a halt: they are ‘cold-blooded’, needing warmth from their environment to allow them to stir. But patchy-cloud days are useful for the photographer, imposing periods of inactivity on insects and other invertebrates which are otherwise difficult to pin down (in the pictorial sense!). Basking Drone-flies and Nursery-web Spiders can sometimes seem to be everywhere, and this week, on 6 April (some two weeks later than typical) Dark-edged Bee-flies emerged in Wivenhoe. Always a delight to see, it was a treat to be able to see these ‘flying-noses’ as anything other than a fast-moving blur.

In calendar terms, Spring is here at last…not that the dismal rain of recent days encourages much in the way of exploration. But in gaps between the showers, every day is moving Nature’s calendar on a notch or two. The first Sand Martins and Swallows have been seen flying through, while Chiffchaffs are coaxed into song at every hint of sunshine and warmth. Buds are bursting before our eyes, vibrant new greens brightening up the greyscape, as violets reveal their welcome intensity underfoot. And not just colour, but also scent, at least with some species. Best of all is the Sweet Violet, bearing a fragrance so intense it can anaesthetise our scent receptors: time then to revert to other identification characters. The picture below may not be a classic portrait, but it does show clearly the bluntly rounded sepals and stems with copious deflexed hairs, features that confirm the species’ identity.

However it is water which defines WildWivenhoe at the moment. Rain, snowmelt, and high tides have conspired to turn most walks into a mudbath. Around Ferry Marsh water levels are especially high, and indeed have been for most of the winter, because of a blocked sluice. Concerns have been raised about this, particularly as a result of footpaths being impassable and also potential effects on our best local population of Water Voles; as a result the Environment Agency is due to deploy pumps in the next few days to try and shed the surplus water.

But, at least from the wildlife perspective, does the flooding really matter? I tend to think not. The clue is in the site’s name: Ferry Marsh…not Ferry Meadows-with-a-few-wet-ditches. Marshes are meant to be at least periodically wet: this encourages wetland wildlife and helps to maintain wetland habitats. Water Voles are quite happy living away from water, at least temporarily, so the only real risk to them is if they are concentrated in particular parts of the site, and then become vulnerable to predation. Water birds are certainly making most of the water, with feeding Little Egret (surprisingly scarce in these parts since the February freeze) and displaying groups of Teal, both on the marsh and the river, taking advantage not only of the expanded habitat but also the lack of disturbance from humans and dogs.

A serious inundation will also do great things for the marshland habitat. One of the greatest problems marshes suffer from is the invasion by trees and other weeds (a weed being any plant which is growing in the wrong place) when the ‘marsh’ is dry: once they get a roothold, they can then dry the marsh out further and exacerbate the problem. A good drowning will help to kill them, and return the marsh to its wetland state. Hopefully, once the reserve becomes accessible once again, the flood will have set the ecological clock back to a time when our valued marshland wildlife is even more at home.