Category Archives: Uncategorized

Sunday Quiz – Bits of Birds – The Answers

Goodness, how well we all did this week! Our joint winners, with 16 out of 16, were Sarah and Fran and Bobby Freelove – congratulations to all. But in honourable joint second place were Alittlebitoutoffocus and Anne – 14 out of 16, and the one place where both of you tripped up was getting your sparrows and finches the wrong way round, a very understandable blip. Thank you all for playing, and if you have any particular preferences for next week’s quiz, let me know, otherwise I shall devise something fiendish.

The answers…..

1) Goldfinch

2) Juvenile Robin (cheeky I know)

3) Starling

4) Shelduck

5) Grey Heron

6) Woodpigeon

7) Jackdaw

8) Long-tailed tit

And now for the bird families. A bit more challenging I thought!

Spinifex pigeon IGeophaps plumifera) by By Andreas Trepte - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=62541555

1) Spinifex pigeon IGeophaps plumifera) – Pigeon family

Photo Two - Blue-rumped parrot Psittinus cyanurus by By Bernard DUPONT from FRANCE - Blue-rumped Parrot Psittinus cyanurus, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=39716041

2) Blue-rumped parrot Psittinus cyanurus – Parrot family

Photo Three by By Jim McCulloch - Flickr: Chimney swift Chaetura pelagica) overhead, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=18278015

3) Chimney swift Chaetura pelagica) – Swift family

Photo Four by By Alastair Rae from London, United Kingdom - Black Woodpecker, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=29371 Black woodpecker (Dryocopus martius)

4) Black woodpecker (Dryocopus martius) – Woodpecker family

Photo Five by By Nigel Voaden from UK - Kurrichane Thrush, Sakania, DRC, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=39984848 Kurricane Thrush Turdus libonyana

5) Kurricane Thrush Turdus libonyana – thrush family

Photo Six by By DickDaniels (http://carolinabirds.org/) - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=21591358 Sudan Golden Sparrow Passer luteus

6) Sudan Golden Sparrow Passer luteus – Sparrow family

Lawrences goldfinch (Spinus lawrencei)

7) Lawrences goldfinch (Spinus lawrencei) – Finch family

By J.M.Garg - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=2902937 White-browed wagtail Motacilla maderaspatensis

8) White-browed wagtail Motacilla maderaspatensis – Wagtail family

So, how did we all get on? I think some families are much easier to identify than others, and with some, seeing a video would probably have made it much easier (for the wagtail, for example). Anyhow, all revelation, comments and requests are greatly valued, as always. In the meantime, see you tomorrow!

 

A Drop of the Sweet Stuff

Buddleia leaf

Dear Readers, today I decided to do a bit of pruning on my two front-garden buddleias. I know it’s not quite the right time of year, but the wind had snapped a branch off of one of them, and the other was starting to hang over the pavement, making it difficult for people to walk past. However, while one of them was in perfect health, the other was not.

Leaves coated in honeydew

My left-hand buddleia has leaves that are sticky and wet with honeydew, the result of a positive plague of aphids, both green and black. I had noticed that the lid of the wheelie bin underneath the shrub was tacky, but I hadn’t really noticed the degree to which the plant had been attacked.

So, what’s going on? It all starts when a winged greenfly lands on a plant. First, it tests the sap of the plant by boring a hole – it has sharp mouthparts but, much as a mosquito injects an anti-coagulant so that our blood doesn’t clot while she is feeding on us, so an aphid injects a substance that stops the sap from coagulating.

Aphids are true bugs, and plant sap is their only food. Furthermore, they feed ‘passively’ – once they’ve tapped into the plant’s juices, sap is forced into the animal’s stomach purely by the higher pressure in the veins of the plant. Plant sap is not a complete food, because it has no protein, but the aphid has gut bacteria to help with that problem. To regulate pressure, the aphid excretes honeydew, which is what is causing the stickiness.

Photo One by By Amada44 - Own work, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=45449058

Aphid producing honeydew (Photo One)

The honeydew is attactive to many sugar-starved insects. Ants will ‘farm’ aphids, drinking the honeydew and carrying the bugs from one plant to another. Some butterflies, such as the hairstreaks, the holly blue, the speckled wood and the white admiral , use honeydew as part of their adult diet. I have seen honeybees licking leaves that are splattered with the sugary secretion, and many solitary bees are also attracted to the stuff. Sadly, if you have ever parked your car under a lime or sycamore tree in summer and have gone away on holiday, you will be giving it a good scrub when you come back. Furthermore, there are types of fungus that grow on the honeydew, disfiguring the plant further. Finally, aphids may introduce plant viruses into a plant with their first bite, even if they then don’t settle and start to feed.

Photo Two by By Kent Loeffler - http://www.ars.usda.gov/is/graphics/photos/apr12/d2459-1.htm, Public Domain, https://commons.wikimedia.org/w/index.php?curid=66276712

Wheat aphid showing its biting mouthparts.(Photo Two)

As you probably know, aphids can perform parthenogenesis – that is, they can have young without mating. Each new aphid is a clone of her mother, and already has the embryo of the next generation maturing within her. In the course of her lifetime, an aphid born in spring could have twenty to forty generations of young in a single season, literally billions of offspring. No wonder my poor buddleia is looking a little overwhelmed.

Photo Three by By MedievalRich, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=3467494

Aphid giving birth to one of her many, many babies (Photo Three)

Fortunately, aphids are the hamburgers of the insect world, preyed upon by pretty much everybody. I found a couple of ladybirds on the buddleia and a small brown hoverfly larvae. There are also twelve species of parasitoid wasps, tiny creatures only a tenth of an inch long, who feed exclusively on aphids – in fact, some of them are used in commercial greenhouses to control greenfly and blackfly numbers without having to resort to chemicals.

Photo Three by By CSIRO, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=35462601

I wondered why the goldfinches that I saw a few days ago were returning to my buddleia over and over again, and now I suspect that they were munching away on the aphids. 83% of the diet of the American goldfinch is apparently comprised of aphids, so why should the UK one be any different? Blue tits will also work over a shrub in search of small, squidgy creatures to feed to their offspring – caterpillars are the favourite, but a beakful of aphids will do at a pinch.

Goldfinch on the buddleia.

Still, I do wonder why one of my buddleia is a sticky mess, and the other is pristine. One is in full sun for most of the day, so maybe it’s healthier anyway? Who knows. What I will probably do is get my long-suffering husband to give the shrub a good burst with the hose pipe next time he’s doing the watering – hopefully that will at least give the aphids a shock. Lots of other methods have been tried: various chemicals (which I won’t entertain, of course – I don’t want to kill off everything that feeds on the greenfly), the insect predators already mentioned, and traps – apparently aphids are attracted to the colour green (no surprise there) so I imagine these traps are about as green as you can get. I think my main aim will be to see if I can bolster the health of my honeydew-covered buddleia – maybe it isn’t getting enough water, especially during the current semi-drought conditions. I will let you know how I get on!

Interestingly, humans have also been fed on honeydew, both in the form of honeydew honey, from bees who feed on the stuff, and in the form of manna – the solidified honeydew found on tamarisk and some other trees. What effect it has on humans is unknown: I just had a tiny taste from the buddleia, and the honeydew tasted, well, sweetish, as you might expect, but not as delicious as maple syrup. But see what Samuel Taylor Coleridge has to say about it, in Kubla Khan. If I can get hold of some Milk of Paradise, I could be flashing and floating all over the place.

And all who heard should see them there,
And all should cry, Beware! Beware!
His flashing eyes, his floating hair!
Weave a circle round him thrice,
And close your eyes with holy dread,
For he on honey-dew hath fed,
‘And drunk the milk of Paradise.

Sunday Quiz – Bits of Birds

Before we start today’s quiz, were you able to identify the bird calls from yesterday? They were, in order: Eurasian curlew, Eurasian skylark, and song thrush. Some of my favourites – this blog is clearly all about self-indulgence. Onwards!

Dear Readers, for this week’s quiz I wanted to create something that could be enjoyed by all my readers, not just my UK ones. But what to do? In the end, I have settled for doing two separate quizzes. In the first one, the challenge is to identify British birds from just a ‘bit’ of them – I’ve made it multiple choice, but be careful! It might not be as easy as you’d think.

For the second part, I am working on the theory that we all have some idea of what a ‘typical’ bird from a family looks like – we could all probably recognise a pigeon, for example, whatever the species was. Or could we? Let’s have a go, and bonus points to people who cannot only identify the bird family, but also the species.

Anyhoo, part one! Identify the bird from the ‘bit’. Apologies for the grainy photos, but I think they give a certain Impressionistic ambience (that’s my excuse and I’m sticking to it!) Have fun!

1)

2)

3)

4)

5)

6)

7)

8)

Answers:

a) Robin

b) Grey heron

c) Goldfinch

d) Jackdaw

e) Long-tailed tit

f) Woodpigeon

g) Shelduck

h) Starling.

And now, let’s see how good we are at putting non-UK birds into their correct families! All of these birds have UK relations. In other words, what makes a duck a duck (though there are no ducks today!) Extra points for the species.

Spinifex pigeon IGeophaps plumifera) by By Andreas Trepte - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=62541555

1)

Photo Two - Blue-rumped parrot Psittinus cyanurus by By Bernard DUPONT from FRANCE - Blue-rumped Parrot Psittinus cyanurus, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=39716041

2)

Photo Three by By Jim McCulloch - Flickr: Chimney swift Chaetura pelagica) overhead, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=18278015

3)

Photo Four by By Alastair Rae from London, United Kingdom - Black Woodpecker, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=29371 Black woodpecker (Dryocopus martius)

4)

Photo Five by By Nigel Voaden from UK - Kurrichane Thrush, Sakania, DRC, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=39984848 Kurricane Thrush Turdus libonyana

5)

Photo Six by By DickDaniels (http://carolinabirds.org/) - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=21591358 Sudan Golden Sparrow Passer luteus

6)

Lawrences goldfinch

7)

By J.M.Garg - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=2902937 White-browed wagtail Motacilla maderaspatensis

8)

Your choices are:

a) Finch (Carduelidae)

b) Pigeon (Columbidae)

c) Wagtail (Motacillidae)

d) Parrot (Psitticidae)

e) Sparrow (Passeridae)

f) Woodpecker (Picidae)

g) Thrush (Turdidae)

h) Swift (Apodidae)

Answers in the comments please, and as usual, if you don’t want to be influenced by speedier responders, write your answers down on a bit of paper first (old-school I know). Good luck! Answers on Tuesday, but if you want to be marked, please get your answers in before 8 p.m. on Monday (UK time). Thank you.

The Ecology of Sound

Dear Readers, as you will have heard my garden has been completely smothered with fledgling starlings this week. From about 5 a.m. there is a wall of sound, which you would think would attract every predator from miles around. Strangely enough, I think that even the hunters find it all a bit baffling – a very handsome black cat appeared and  was bombarded with such a barrage of screaming alarm calls that he gave up looking sneaky and just walked nonchalantly down the steps and past the pond, as if killing things was the very last thing on his mind. The magpie and the sparrowhawk have been notable by their absence, and in short, I think that this year there are so many fledglings that no one can make up their mind which one to eat.

To get an idea of the cacophony (and this is a very poor sample) have a look here.

Anyhow, all this got me thinking, and so I was glad to attend a very fine talk on Passive Acoustic Monitoring, given by Richard Beason for the Field Studies Council. You can watch the whole thing here. Passive Acoustic Monitoring is the name given to leaving a sound recording device somewhere in nature, and coming back later to download the results.

Increasingly, these devices are being used to record soundscapes – the whole range of sounds that can be heard in an environment, from the wind and rain through the calls of frogs and birds and crickets, to the sound of ancient timber being cut down by a chainsaw (oops). When you’re done, you can play the recording back, but many also come with spectrograms, which enable you to get a visual representation of all the racket.

Credit: Spectrogram©MichaelTowsey&AnthonyTruskinger,QueenslandUniversityofTechnology

One of the most interesting revelations, for me anyway, was that in a habitat, the inhabitants not only occupy geographical niches, but also aural niches. I’d never thought about it before, but if all the animals were calling at the same time, no one would ever hear anyone else. The way that it works is that different animals call at different frequencies, at different times, and often in different rhythms, so that everyone gets their share of the ‘sound stage’. Even in the UK we can see how this works, with soprano and common pipistrelle being distinguished mainly by the fact that their calls are at different frequencies. This way it’s unlikely that bats of different species will end up breeding together.

Photo One fromhttp://www.bio.bris.ac.uk/research/bats/britishbats/batpages/commonpipi.htm

Calls of the common pipistrelle (Pipistrellus pipistrellus) (Photo One)

Photo Two fromhttp://www.bio.bris.ac.uk/research/bats/britishbats/batpages/sopranopipi.htm

Calls of the soprano pipistrelle (Pipistrellus pygmaeus) (Photo Two)

What PAM allows you to do is to see what’s living in a particular place, and compare it to similar habitat elsewhere. Firstly, of course, you have to identify all the sounds, which can be a very demanding task. From just looking at the sonogram, what bird do you think this is?

 

And if you’re stuck, you can have a listen to the bird below.

Once everything has been identified (and you’d better hope that there aren’t any starlings beat-boxing, or lyre birds pretending to be a camera on automatic ) it’s interesting to see how the spectrograms compare between, say, virgin rainforest and a palm oil plantation. And indeed spectrograms are being used in conservation in a variety of ways – in the Central African Republic, placing acoustic monitoring devices in the forest has led to the discovery of an important area where the rare African forest elephants gather to find minerals. In the diagram below, the blue dots are monitoring devices, and the red dots are the mineral licks. The discovery of the one in the south will make it easier to protect this area, and to think about how to create a corridor to the ones in the north.

Photo Three fromhttps://methodsblog.com/2017/08/11/passive-acoustic-monitoring-elephant-conservation/

The blue dots are the monitoring devices, the red dots are mineral licks. (Photo Three)

Perhaps the most interesting thing, though, is how PAM can be used to both identify a problem, and suggest a solution. For example, in 2012 it was discovered that healthy coral reefs sound rather like popcorn, with a great chorus of fish chomping and calling and snapping- shrimps walloping things.

https://www.nhm.ac.uk/content/dam/nhmwww/discover/audio/sound-of-coral-reef.mp3

Other fish use these sounds to orientate themselves and to find a new reef, because a busy reef is a safer reef, and it is also a place where a fish can find something to eat and someone to  mate with. But after a coral bleaching event, the reef is silent, and even after it starts to recover, the fish don’t return because they can’t hear it. So the answer appears to be what’s known as ‘acoustic enrichment’ – putting down underwater speakers which play the sounds of a healthy reef. Slowly but surely, the fish return, and make their own sounds, and after a while the speakers aren’t needed anymore. I find it fascinating how this whole cycle has been identified and how imaginative the solution is. In these times of crisis, I get a real lift from every piece of creativity that’s used to help preserve our beleaguered planet. Who would have thought that a couple of speakers would have increased the diversity and number of fish on a damaged reef by 50%? Furthermore, once the fish have found the reef they tend to stay, and their activities help to build the ecosystem of the reef. You can read the full story here.

PAM has been used in many other ways: to monitor the change in the population of Leach’s petrel in Northern Canada after the removal of Arctic foxes, and to estimate the number of anti-poaching patrols required in Central African Republic by recording the number of gunshots. It really is a area with endless applications, and a great addition to our environmental  toolbox. In lockdown, the sounds of nature become much more prominent, a whole new way of appreciating the world. Let’s hope that we continue to appreciate them once things get back to whatever will pass for normal in the future.

And here, just to round off this very sound-based post, here are three of my favourite birdsongs. All of the singers used to be common, but none of them are now. See if you know what they are! Answers tomorrow.

 

 

 

Friday Books – Wildlife Gardening

Dear Readers, today we have three books that have been indispensable to me in my endeavour to make my garden a haven for wildlife. First up is Adrian Thomas’s Gardening for Wildlife, a superb all-round book on everything from the species that you might see to how to create a particular environment.

Thomas describes the different requirements for different species, but also points out that it’s difficult to actually ‘attract’ wildlife to your garden (though having been awoken at 5.30 this morning by the starlings I’m not sure I’m convinced!) His point, though, is to cherish what you already have locally – there is no point in growing flowers for a butterfly that was last seen in your area in 1786 for example. The book is full of fascinating facts: for example, speckled wood butterflies much prefer the honeydew secreted by aphids to any flower.

There are lists of flowers for bees, butterflies and moths, and these are by season too. There’s stuff on ponds and bat boxes, but also on making your own woodland garden or area of scrub or bog.  In particular, I like that when Thomas recommends a plant, he gives you an idea about the variety that works best, so you don’t waste a lot of time on something unsuitable. If I only had room for one book this would definitely be it.

This is a great, great book – I heard Jan Miller-Klein speak at a meeting of the Wildlife Gardening Forum, and she is such an enthusiast. This book is a real labour of love: Miller-Klein doesn’t just look at planting for adult butterflies, but also considers their foodplants. She has ideas for planting an insectary, which encourages predatory invertebrates such as lady birds and spiders, and a dyer’s garden with weld and woad and all sorts of exciting plants. There are ideas for a moraine garden, and for containers and raised beds.

The beneficial plants are laid out by season, so that you can make sure that there’s always something going on for pollinators.

She doesn’t forget dragonfliies, beetles and moths either.

And at the front of the book there’s a quick gallop through the best plants for each time of year. I would never have thought of hemp agrimony for the pondside in my garden without Jan Miller-Klein, and it’s probably the most popular plant that I grow with the butterflies and bees.

And here’s an old favourite.

This book is such a delight. It concentrates mainly on the behaviour of birds, and I learnt a lot from it. I had no idea that the male wren builds lots of ‘starter homes’ in his territory to attract the ladies, and then abandons each one to get on with rearing the youngsters on her own. And starlings will lay eggs in the nests of their neighbours when they aren’t looking. And a small number of unpaired male swallows will perform infanticide if a female is widowed or unhappy with her partner. Goodness! The shenanigans is really something to behold.

The illustrations, by Peter Partington, are lovely too. This is a book that aims to increase the richness of our understanding of the creatures closest to us, and I am always dipping into it.

Dominic Couzens has done a number of books for the RSPB, but somehow this is the most charming.

So, those are my favourite wildlife gardening books, though I have a great pile of books still to read. Dave Goulson, who wrote the excellent ‘Sting in the Tale’ about bumblebees, has a new book called ‘The Garden Jungle’ which I got for Christmas and still haven’t read, so i think this is a subject that will bear some revisiting. Let me know what your favourite garden wildlife books are, I am always keen to add to my book pile!

A Quick March around the Playing Fields and Daily Starlings

Wood millet (Millium effusum)

Dear Readers, on Mondays, Wednesdays and Fridays our early morning walk through Coldfall Wood and Muswell Hill Playing Fields is at quite a pace, because my husband has to get back for a 9 a.m. call. Hence today, as I galloped along, I was able to snatch a few photos but couldn’t linger, for fear of being tardy. And so, I am throwing myself upon your mercy. I have always been interested in grasses, and in particular the way that they are so well adapted to the habitats that they find themselves in, but my identification skills are approximately zero. So, if you think I am wrong about any of the species I’m writing about, do not hesitate to put me right.

First up is what I think is wood millet (Millium effusum), growing amongst the hornbeams in the shadier parts of the wood. I love the way that each individual seed is lit up in the sunshine – it is a most ethereal plant. It’s said to favour winter-wet clay soils, and there’s certainly plenty of that lurking in Coldfall Wood.

Couch grass (Elymus repens)

We head out into the sunshine at a spanking pace but I manage to get a quick photo as we move along the side of the playing fields. This looks rather like couch grass of some variety: if so it is something of a pain for gardeners, what with its creeping rhizomes. However, finches and buntings like the seeds, and it is the one of the food plants for the Essex skipper butterfly.

Photo One byBy Charles J Sharp - Own work, from Sharp Photography, sharpphotography, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=33951282

Essex Skipper (Thymelicus lineloa) (Photo One)

At least social distancing on the Fields is relatively easy (even at speed) – one can always cut a corner to avoid a runner, and at least you can see people coming. As the temperatures are going into the ’80’s today, though, I do wonder if there are enough 2 metre squares of grass in the whole of England for everyone to sit on, now that we’ve been told that we can sunbathe. Of course, we must simultaneously ‘stay alert’, which rather ruins the whole idea of relaxation. In spite of this I have yet to see a virus, although I know some people in the prime of their lives who have caught it, and are finding that it’s a disease with a very long ‘tail’ that brings with it total exhaustion for weeks and weeks. I for one shall be walking briskly and sitting in the garden (and yes, I really do know how very lucky I am to have one).

Onwards! Another (probably inaccurately identified) grass is this rather dangly chap. It’s growing on the very edge of the fields, and I didn’t manage to capture the way that it sways in the breeze. I think that it might be hairy brome (and even if not, it’s a wonderful name). Hairy brome apparently likes shade, and this was a relatively sheltered spot. I believe that it could also be false brome, or even a fescue. Help! I’m sure there are some gramnophiles out there who could assist. I looked up the phrase ‘grass lover’ on Google to see if there was a special word for such a person, and I guess you can imagine which kind of sites I found.

Hairy-brome (Bromopsis ramosa) or possibly false brome (Brachypodium sylvaticum)

We stomp around the edge of the stream that brings all the run-off from the surrounding area into the woods, and there is my old friend, pendulous sedge. If you have a pond and leave it for more than ten minutes, one of these plants will soon arrive, and within the hour it will have had thousands of babies and distributed them into every nook and cranny. It is, nonetheless, a rather handsome plant (though, as the name suggests, a sedge rather than a ‘true’ grass) and it served the valuable purpose of hiding all my froglets from predators. However, it also has other uses, one of which is that the seeds from all those dangling seedheads can be made into flour. Who knew? Furthermore, unlike other grasses and sedges, pendulous sedge is not prone to the poisonous fungi ergot, which causes hallucinations, limb cramps and convulsions (more commonly known as St Anthony’s Fire).

Incidentally, you can tell a sedge from a grass because a sedge cross-section is triangular. So now we all know.

Pendulous sedge (Carex pendula)

And finally, as we head out past the electricity sub-station, I spot an old friend.

Wall Barley (Hordium mureum)

How we used to love playing with the seedheads of wall barley when we were children! You could pull the seeds apart, you could throw them at one another, and at one point I had them in my ‘zoo’ as ‘sheep’. The ‘zoo’ was polystyrene tiles left over from doing some work on the ceiling (yes, this was the 1960’s and polystyrene-tiled ceilings were all the rage in the East End), and the fence around the ‘field’ was made from spent matches and used drinking straws. The ‘house’ for the ‘sheep’ was made out of Lego. Now, if only I could have persuaded my brother not to run them all down with his toy tractor we would have been in business.

And finally, we are just reaching peak starling, I hope. The fledglings started squealing for food at 5 a.m. this morning, and are still going twelve hours later. Isn’t anybody else feeding them? At one point there were fifteen lined up on what was my pristine new handrail, and which will now require a very thorough scrub. I am pleased to see that the branch that I put into the pond so that the little birds could access a drink is being put to good use though. I just hope that all the fledglings learn to feed themselves soon and will pipe down,  before I am driven out of East Finchley by neighbours bearing pitchforks and lighted torches.

And yes, the water level in the pond is down again, though hopefully just because we’ve had no rain rather than because a heron has stabbed the lining again. We have had maybe 2 substantial days of rain since lockdown started in mid-March. It is the sunniest, most beautiful spring that I can remember which helps a bit, at least for me. I hope that you are managing too, wherever you are.

Wednesday Weed – Hoary Cress

Hoary cress (Lepidium draba)

Dear Readers, Muswell Hill Playing Fields has been a most unexpected source of interesting Wednesday Weeds over the past few weeks, but I was stumped when I first saw this plant. It reminded me somewhat of a white sedum, with its mass of snowy-white flowers and rather waxy green-grey stem, but a quick glance at my Harrap’s Wildflower Guide showed me that I had found another brassica; Hoary Cress. Apparently it is also known as ‘whitetop’, for obvious reasons.

This is a plant that is a long way from home, though: native to south-west Asia and southeastern Europe, it is treated as an invasive weed in both the USA and Australia, where it probably arrived in contaminated seed. In the UK it arrived in the early nineteenth century: in Alien Plants, Clive Stace and Michael Crawley suspect that it probably arrived in ship’s ballast. And therein hangs an interesting tale.

Ship’s ballast was comprised of gravel, sand, stones etc that were placed into the hold of a ship to give it stability and stop it capsizing. It’s easy to see how collecting this material in one port, and then emptying it out when the ship was at the end of its journey, could easily transport plant matter from one place to another. The first recorded case of it, according to Stace, was in 1627, when Francis Bacon reported that:

‘Earth that was brought out of the Indies and other remote countries for ballast for ships, cast upon some grounds in Italy, did put forth foreign herbs, to us in Europe not known’.

Ballast was sometimes dumped at sea, but this ran foul of harbour regulations and incurred a high cost when dredging was required to re-establish safe passage. As a result, it was increasingly left on the land, forming ‘ballast hills’ which must have been a botanist’s delight as alien species germinated. Some ports were more important for this than others: Newcastle, a port where ships went out carrying coal, and came back empty except for ballast, was a prime site for ballast-dumping, whereas London, which was largely an importing port, wasn’t the recipient of a lot of ballast (though alien plants often arrived with the cargoes themselves). The initial entrance site for the plant is established to be Swansea (another coal exporting port) in 1802, but this hasn’t stopped a whole array of stories about the plant’s supposed initial arrival (see later).

Ballast more or less disappeared as a source of alien plants as soon as iron hulls replaced wooden ones, but a number of plants were established by then. The most famous is probably pineappleweed, but in Cornwall prostrate toadflax (Linaria supina) probably arrived in this way.

There is little doubt that hoary cress was also imported with straw brought in for fodder, so it had at least two ways of arriving in the UK. Which ever route was the most important, it has earned the epithet ‘curse of Kent’ and is also associated with the area in yet another name, ‘Thanet Cress’, though it is now found in most parts of the UK. Stace describes it as an ‘aggressive rhizomatous species’. I find it interesting that it has turned up alongside the Playing Fields, much as I was puzzled about the oil-seed rape that is all over the place. I find myself wondering if these have emerged from an agricultural seedbank, dating from when the area was ‘proper’ fields rather than playing fields. I shall have to dig out some maps of the area and have a look.

Stace notes that hoary cress is also often a component of the cheap ‘cornfield seed mixes’ that are sold in order to generate an ‘instant meadow’. I think that this is quite an attractive plant, but that, if the playing fields are anything to go by, it’s also something of a thug – I suspect that the poor old cornflowers and poppies would soon be inundated by a sea of white. There is much to be said for buying such seeds from reputable sources if you want to end up with native species: there are many ‘lookalikes’ which are not the same as the ones that actually evolved here. Still, there is no way that the flora around East Finchley is ever going to be made up of exclusively native plants, and the species from other places make for a most interesting mix.

Stace also points out that in some ways, hoary cress is the ‘ideal’ alien: it doesn’t need any fungal support to spread, it can self-pollinate and spread via its rhizomes, and the seeds are wind-pollinated. In short, given a head start it could take over the world! And it might do this via motorway verges, where it is often found growing alongside oilseed rape. I can imagine those wind-dispersed seeds being blown along the road with each passing car, gradually travelling to every part of the UK.

The plant is also sometimes found in coastal areas, and seems to be highly salt-tolerant, which makes me wonder if the salting of motorways during icy periods has helped it to spread, much as Danish scurvy-grass has.

Now, during the lockdown I have found my thoughts often turning to food, and so naturally I wondered if this member of the cabbage family was edible. Results seem to be mixed: Wild Food Girl in the US uses the young plant in the same way that I would use tenderstem broccoli, and reports that tasting the flowers raw ‘nearly blew my head off’. The Hunger and Thirst website describes it as ‘delicious’. Nearly everyone is very specific that the plant should be eaten ‘young’, and some suggest that you could use the leaves raw, though they also mention that the plant contains hydrogen cyanide so you maybe shouldn’t be too overenthusiastic. As a great lover of broccoli I am almost tempted to have a bash myself. If the blogs suddenly stop arriving, you’ll know what’s happened.

Photo One from https://wildfoodgirl.com/2013/whitetop-a-wild-invasive-substitute-for-broccoli/

Hoary cress and oyster mushroom quiche by Wild Food Girl (Photo One)

Medicinally, the plant has been used to counteract scurvy (like all brassicas it is a good source of Vitamin C) and is said to also be good if you have contracted food poisoning by eating contaminated fish. This seems very specific: I almost wonder if its link with docks and the sea is coming into play here. However, in Plant Lives, Sue Eland mentions that rather than treating food poisoning, the seeds were used as a way of poisoning fish, so that they would float to the surface for easy harvesting – I’m guessing that the hydrogen cyanide was involved.

I went looking for folklore about the plant: often when a plant is a relatively new arrival, there isn’t much to say about it, at least in the UK. I found one ‘creation myth’, from an elderly lady who lived in Whitstable in Kent: she said that the hoary cress had arrived during the 1914-18 war, in the straw brought to feed the horses that were being shipped to the front. Sadly, we know that the plant actually arrived in Swansea a hundred years earlier, but of course plants do arrive in different areas at different times. The war link will not go away, either: in Vickery’s Folk Flora there is a story from the Westminster Gazette of 6th May 1915.

When our troops disembarked at Ramsgate after the disastrous Walcheren expedition of 1809. the straw and other litter on which they had slept aboard ship was thrown into a chalkpit, and afterwards carted into the fields for manure by a farmer called Thompson. A huge crop of the plant (Lepidium draba), thence named ‘Thompson’s Curse’, sprang up, spread right across England, and is now attacking the North Country. The roots of this terrible pest are many feet in length’.

And now a poem. This is actually about a different weed, spotted knapweed, but it could in essence be about any invasive plant, introduced accidentally or for a different purpose, but suddenly out of control. And, like all good poems, it is actually about much more than just a weed. See what you think.

Weeds by Dennis Held (from ‘Betting on the Night‘)

Blessed fiend, sultan of the sagebrush,

spotted knapweed of thee I sing,

bowed before thy spiked tenacity.

 

Cousin to other floral marauders

unholy cadre we honour with sacred

pagan names;dalmatian toad flax

 

dyer’s woad, purple loosestrife, leafy

spurge, hawkweed, cinquefoil,

hoary cress. Knapweed, you’re

 

a hired gun gone amok, imported

by beekeepers greedy for late

summer blooms, but soon

 

you outgrew the pasture

and blasted free, root-fed

toxins offing all around:

 

pedestrian bunch grass,

hyperbolic balsam root,

range-hardened sage,

 

croaked by your democratic

methods-all must die-

just doing what you have to,

 

doing what you can

and you have done it all:

invaded, took over,

 

wiped out the locals,

poisoned the ground,

wasted the water

 

moved west, ever west

and hell, that’s why we fight

so hard to purge you in futile

 

“War on Weeds” campaigns,

knowing we’ll fail, miraculous

centaurea maculosa, impure beast

 

half human, we love

and hate you best,

the honeyed weed within.

Photo Two By Matt Lavin from Bozeman, Montana, USA - Centaurea maculosa, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=14711862

Spotted knapweed (Centaurea maculosa) (Photo Two)

Photo Credits

Photo One from https://wildfoodgirl.com/2013/whitetop-a-wild-invasive-substitute-for-broccoli/

Photo Two By Matt Lavin from Bozeman, Montana, USA – Centaurea maculosa, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=14711862