Botany – David Bradley

Mistle Thrush on the Mistletoe

For years our ailing rowan tree had a clump of male mistletoe, the neighbour’s much healthier tree was host to a berry-laden female that attracted a Mistle Thrush. The bird has a cackling call unlike the melodious and repeating sound made by the Song Thrush.*

Then, a couple of years ago, we sprouted a berry-laden female of our own and now the Mistle Thrush jealously guards its crop from other birds that might snaffle its berries.

The scientific name for this bird is Turdus viscivorus. Turdus is Latin for thrush, viscum is Latin for sticky. European Mistletoe Viscum album, album meaning white (for the colour of the berries).

Now, mistletoe is a hemi-parasite that relies on its berries being eaten by birds like the Mistle Thrush to complete its reproductive cycle. The bird’s digestive tract does not process the whole berry and it will excrete a dollop of partially digested berry with an intact seed within. The sticky mass requires a wipe and how better than to do that against the bark of a tree. Once detached from the avian cloaca, the dollop of berry with seed will germinate and embed into the host tree. It will tap into the tree’s nutrient and water supply, but as you can see mistletoe is not wholly parasitic, this evergreen species is replete with chlorophyll in its leaves and can carry out photosynthesis to make sugars from water and atmospheric carbon dioxide. Some of the sugars it makes will most likely help sustain its tree host.

Incidentally, mistletoe berries are not actually berries, they’re drupes. A berry is defined botanically as a fleshy fruit produced from a single plant ovary, with seeds embedded in the flesh. Examples include tomatoes and blueberries. A drupe, by contrast, is a fruit with an outer fleshy part and a hard, stony pit that encloses the seed examples of drupes are cherries, peaches, olives, and mistletoe berries. It’s worth noting that they are potentially fatally toxic, so if you do hang some mistletoe at Christmas, be cautious if you have pets and children around. American Mistletoe is a different species and less toxic but ingestion is still capable of giving you a serious stomach upset.

The presence of mistletoe on trees is a good sign of low atmospheric pollution in the neighbourhood.

*I strongly suspect that the bird in the song A Nightingale Sang in Berkeley Square (lyrics Eric Maschwitz, music Manning Sherwin, 1939) was actually a Song Thrush, rather than the less common summer visitor, the Nightingale, which would likely not have frequented the urban environment of Mayfair even before World War II. The song was actually written in Le Lavandou, a fishing village in France, where Nightingales were probably heard far more often than in the posh bits of London.

Apple of Sodom

As regulars to the Sciencebase site will know, I’ve been doing some ad hoc wilding of our garden for a few years now. Always hoping that blooming wildflowers would attract interesting invertebrates. There are therefore patches and pots that I’ve not managed with all sorts of odd things sprouting from them at different times of year. At the moment, there is a big tub, which used to be crocuses and daffodils that has a very tall and leafy plant growing in it at the moment, with pale-purple flowers in bloom (it’s November!).

I used the ObsIdentify app to take a couple of photos and it turns out to Apple of Peru, Nicandra physalodes. The species is also known as the shoo-fly plant (it repels aphids and other flies and although toxic is sometimes rubbed on the skin as an insect repellant. It’s also known as the Apple of Sodom, presumably somehow that relates to its encapsulated poisonous fruit.

As the name would suggest, Apple of Peru is a native to South America, self-seeds easily, and is sometimes grown as a decorative annual. I didn’t plant it, seeds from some outside source presumably landed in the tub and it’s grown where it fell. I think it’s meant to be in bloom from April to July, usually in tropical and sub-tropical climes rather than the temperate zone, so not entirely sure what it’s doing with open blossom now and setting fruit in the middle of November in England.

Bluebells and Oxlip at Overhall Grove

We discovered Overhall Grove woodland many years ago through a book of woodland walks given to us by the aunt and uncle of Mrs Sciencebase. It’s a small nature reserve, mature woodland, lots of Bluebells and Oxlips in spring, various butterflies too, including White-letter Hairstreak, which I mentioned here in the summer of 2021. Anyway, a visit today was mainly for the Bluebells, the walk, and the fresh air.

A scarce flower for Passover and Easter

We took a walk along the Devil’s Dyke hoping to see Green Hairstreaks and perhaps the Dotterals that had been sighted on neighbouring Ditch Farm. We had no luck with either of those, although there were lots of Brimstone butterflies, a few Whitethroats, and our first Willow Warbler of the year.

Almost in passing we noticed a pretty purple flower with a yellow centre. Mrs Sciencebase suggested it might be some kind of anemone and it is indeed in the same sub-family, Ranunculoideae, but it is specifically Pulsatilla vulgaris, known colloquially as the European Pasque Flower. Pasque from the Hebrew word for Passover, Pasakh. Obviously, quite apt for this time of year.

The plant is also known as the wind flower, prairie crocus, Easter flower, and meadow anemone. The showy purple parts are sepals rather than petal. It’s a scarce plant that likes chalky or limestone-rich land. Happily, the very substance of the raised earthworks that is Devil’s Dyke is a good proportion of chalk. It is also the ‘county flower’ of Cambridgeshire and neighbouring Hertfordshire. Pulsatilla species are toxic and can cause vomiting and diarrhoea if ingested and in serious cases of poisoning, convulsions, a critical drop in blood pressure, and coma.

Thanks to Twitter friends for the ID, one, to my chagrin, I did not know.

Counted 11 hares on adjacent farmland, lots of cowslips, lots of Brimstone butterfly, one or two Small Tortoiseshell, half a dozen European Peacock and lots of the same beige moth (perhaps a caddisfly?)

The Feral Crocus

My very good friend, photographer Diana Sanders took a lovely shot of a yellow crocus growing wild near her home. She posted the photo to acclaim on her Facebook describing it as:

Like a candle flame amongst the dead leaves. If we get any more hard frosts it won't look so cheerful, though.

It triggered me to write a short poem:

The Feral Crocus

A feral crocus nestles among the long-dead leaves
A glimmer of hope, a tiny, shining candle of life
Its flame burns bright among those oaken thieves
Their dew can’t steal this golden light

But Arctic winds might rustle those chilling leaves
And times are hard and so could be the frost
The dew that’s stilled will begin to freeze
And snuff that flame then forever lost

Still, there is hope as it is overcast
The cloud-filled skies blanket all below
The bloom won’t face an icy blast
And tomorrow, we can bask in that feral crocus glow

Twitching wildflowers

The rather derogatory term “twitching” (see definition in my tongue-in-beak bird glossary) is usually preserved for someone going out of their way to see a rare bird…but those with an interest in seeking out natural wonders may well twitch anything. Yesterday, I took my daily walk partly along the Cambridge to Stives guided busway to “twitch” the bee orchids that are thriving sporadically along the wild margins of the route.

While I was walking back to my turning-home point, I bumped into a group of people who were well aware of the bee orchids, pointed out that there were also some pyramidal orchids around and explained that they were (mostly) amateur botanists out for a day’s botanising (the wildflower equivalent of birding and mothing, I presume).

The plant that had taken their interest at the time I stopped to talk them wasÂ a seemingly mundane specimen in the impacted dirt at the edge of the by-way and guided bus cycleway. What made it interesting was that it was a maritime species, a wildflower that should only be seen growing along our coasts. Now, given the number of wading birds that seem to have taken to being landlubbers these last few months in and around our village, it’s perhaps no surprise that a maritime plant species will have taken root, perhaps a seed having hitchhiked among the feathers of one of those coastal waders or been delivered in conjunction with a bird’s inflight fertiliser in the form of avian guano. I think this is the plant, but there were several others around it, so not sure, and no idea of its ID.

Mystery maritime – Is this a coastal plant that has become a landlubber?

The wildflower meadow myth

What could be more natural more evocative, more quintessentially English than a wildflower meadow nestled in the countryside, teeming with bees and butterflies, day-flying moths and countless other pollinators perhaps home to some ground-nesting birds and dozens of tiny mammals, a complete ecosystem when coupled with the natural reservoir in the neighbouring field?

And your wilding projects? Often the packs of seeds we scatter in our gardens to create a wild area or on roadside versions are cultivated mixes of cornflower, ox eye daisy, borage, (bizarrely) California poppy, and a few others. That said, I’ve tried to grow something more naturalistic by seeding corn cockle among the cornflowers, no ox eyes, but plenty of borage, viper’s bugloss, wild marjoram, opium poppies, yarrow, mallow, and the erroneously maligned ragwort.*

Well, sorry, but no. Not much of its not natural, it may be beautiful and conjure up images of a sadly lost past that never really existed, but many of what we call native wildflowers are anything but. Established wildflower meadows may well have taken hundreds of years to become established ecosystems. But, they arrived with humans who brought their agriculture from the Middle East in the stone age. Many of the species we consider essential to stocking a wildflower meadow are native to North Africa and the Mediterranean. They never grew here until the arrival of cultivated grassy food crops just a few millennia since.

Of course, many species in many different countries are not native, there have been so many changes to the climate and the geography and geology of the world over millions of years. What’s a few millennia between friends? Let’s cultivate the wildness anyway…

All of that said, it’s better to wild than to cultivate. Moreover, there is an argument that even if some of the so-called native wildflowers arrived with agriculture from the Middle East who’s to say that some of them weren’t growing here before the last ice age when the British mainland was conjoined to the European continent and the footprint of the landmass and the geography of the present Middle East were all very different?

*Ragwort: Erroneously maligned as a livestock and horse killer. Yes, it is toxic to cattle and horses and other animals and it’s sensible not to let it grow on pasture. However, it’s only a problem if the animals are not getting fed properly. It’s got a really bitter taste and most animals (Cinnabar moth larvae aside) will avoid it. However, it can end up in sileage when its bitterness might be masked by other plants in the mix and the animals quite happily tuck in and suffer.

Fruit of The Tall Sock Destroyer

This unassuming plant, flowers and fruit in the photo, which just happens to be growing locally along the edge of a sugarbeet field, is actually an endangered species on the “red” list…it’s a type of wild carrot that goes by the scientific name of Torilis arvensis, but you can call it The Tall Sock Destroyer*

*It’s also known as Spreading Hedgeparsley, which sounds more like a skin disorder people who run through amber fields of grain might get rather than the worst-ever Marvel comic superhero…

Its fruits have sticky little purple barbs that under normal circumstances cling on to the wool of passing sheep and the fur of other animals and spread the seed wherever those animals might graze. In times of herbicide use and less brazen shepherding, the plant has not thrived and is very much endangered, so it’s lovely to know that it’s growing on the outskirts of our fen edge village in Cambridgeshire. NB This is only the second time I’ve “twitched” a plant.

Spreading Hedgeparsley, The Tall Sock Destroyer

There’s a growing list of wildflowers classed as endangered in The British Isles, among them Apparently, Spreading Hedge-parsley, also known as the Tall Sock Destroyer. A friend of mine, Pam, spotted some growing along a sugarbeet field margin on the north edge of our village. I had to “twitch” it, it seemed so exotic.

It’s a delicate-looking plant of the carrot family, I was not particularly worried about ruining my socks even if that vernacular name sounds like its the worse of the DC/Marvel superheroes. Identification has now been confirmed by the county recorder here in VC29. So, here’s one of my snapshots of Torilis arvensis.

Let’s hope its presence in our village persists. It’s a good sign if we are seeing endangered species growing again, it could be their comeback. It would be interesting to know whether this is a positive effect on the environment of reduced traffic and human activity because of the Covid-19 lockdown. Who knows? And, after we ease lockdown will things revert to their problematic pre-pandemic condition?

Torilis arvensis fruit bodies – Photo by Pamela Newman

The bristly seed-bearing fruits have slightly curved bristles which presumably readily stick to the wool of grazing sheep and the wool of hikers’ socks. Its decline is mostly blamed on agricultural herbicides but the lack of grazing sheep on intensively farmed arable land in modern agriculture may also be to blame for the seed not to be spread as widely as it once was.

Torilis arvensis flowers – Photo by Pamela Newman

The pyramidal orchid

A friend tipped me off that he’d spotted an unusual plant species, Anacamptis pyramidalis, the pyramidal orchid, in our local woodland. It’s in a very prominent spot where lots of people walk their dogs so was unlikely to last long. I headed there this morning to do my first botanical “twitch”.

Took a Canon 6D and a Tamron 90mm macro with a tripod and a flash to try and get a decent close-up or two. I didn’t even think to sniff it, but apparently it has a “foxy” scent.