Cherry Plum

The cherry plum Prunus cerasifera is one of my favourite “native”* British trees. It was originally recommended to me by a local beekeeper as the easiest and most reliable tree to provide early forage for honeybees. He was right; the new cherry plum in the garden here started flowering at the beginning of March this year, and I have known them to flower from early February. What a lovely harbinger of spring!

cherry plum and honeybeeTheir blossom is attractive enough for them to be mistaken for their distant cousins, ornamental cherries, although to mind non-botanical mind the cherry plum is more like Blackthorn. The flowers look similar, it’s as good a plant to lay in a hedge and has the odd spike to keep you wary of it. Although cherry plums are self fertile, the fruit doesn’t appear reliably. The fruit is said to make good wine, chutney or jam – i.e. it’s bitter!- although the birds like it.

They are very vigorous and disease free trees, and seemingly tolerant of most conditions. I guess this is what makes Myrobalan (a synonym for cherry plum) such a good rootstock for domestic plum trees. The trees are neat and small, forming nicely shaped heads up to around 8m, with healthy looking glossy foliage. They’re tough as old boots and make excellent fast growing windbreaks. We planted some around our old orchard, which was a great success. In the garden of our new house they’re doing equally well, to the delight of my honeybees.

You often see the pink flowering cultivars in gardens, most probably P. cerasifera ‘Nigra’, which has lovely dark purple foliage.

* it was introduced from south eastern Europe, but is now naturalized in the UK.

Bees and Pesticides

The bees and pesticides argument rages on. I won’t bore you with the minutiae of the current debate on neonicotinoids, but let’s just say the quality of it leaves something to be desired. There’s much bloody mindedness, politics, mudslinging and finger pointing going on. I’m pleased it has highlighted the decline in bee populations though, which seem to me to be the canary in the coal mine. A ban on neonicotinoids would of course be helpful, but I’m increasingly concerned that folk see this as an instant panacea. Once this single and high profile issue is sorted out – as I hope it will be – then will all be well again? I’m afraid it won’t.

We’re talking here mostly about honeybees and pesticides, as they’re the only bee we know much about. They have a lot to cope with at the moment other than neonicotinoids. For a start there has been the weather here. I have lost a really nice swarm which I hived last summer. Heartbreaking. I did everything right, but they just gave up. Most of my competent beekeeping friends report significant mortality over the extended winter, following last year’s filthy summer. These are experienced beekeepers who keep their bees really well; they’re not over-interventionist or “commercial”, nor do they just trust to luck. We’ve all dealt with the recent enemies of honeybees – nosema and varroa – but this is a new battle.

Bees and Pesticides
Photo: Penn State University
Yesterday I went to a fascinating talk by Maryanne Frazier, of Penn State University’s Centre for Pollinator Research, on bees and pesticides. This reinforced the multiple challenges honeybees are facing. Like many honeybee scientists, Maryanne’s best guess is that there is no single smoking gun behind bee declines in the U.S., but rather a complicated matrix of factors weakening honeybees’ immune systems.

Bees and pesticides don’t mix, and the coktail of pesticides her team are finding in pollen and wax are horrific. They found 31 pesticides in one pollen sample. The average is 6, which is bad enough*. These pesticides can have sub-lethal effects, they can be systemic (like neonicotinoids) and they impact on larva and adult bees in different ways, so their effects are difficult to assess.

What’s worse is that they can be synergistic, so that in combination their impact can be much more extreme than you can predict. Neonicotinoids are very toxic, but more traditional pesticides combine to have really unpleasant effects on colonies. This is true of fungicides and miticides too. Why do I mention miticides? The vast majority of wax in U.S. hives has traces of stuff called Fluvalinate, which was routinely used to wack varroa mites and combines unpleasantly with other pesticides. Fungicides too can be dangerous to bees as they impact microbial activity in the bee gut. Bees also suffer much more exposure to them, as they’re used indiscriminately.

There’s also an issue in the U.S. with the vast monocultures that migratory bee colonies are asked to pollinate. Honeybees are “polylectic” – that’s to say that like Bumblebees they prefer different types of forage to provide a varied and healthy diet. Large scale U.S. commercial beekeeping must add to the strees that these honeybees experience.

So what does Maryanne recommend we do?
1. Manage our honeybees better. We can’t just leave them to fend for themselves, but we can adopt better beekeeping practices. I’d like to think they’re the sort of things I promote already. Change wax regularly, leave lots of stores so artificial feeding is only necessary in dire circumstances, and leave be throughout the autumn and winter months. It’s not rocket science.
2. Provide diverse and season long sources of forage.
3. Improve our regulatory agencies. As in the U.K., U.S. regulators are only interested in the lethal effects of individual toxins on a small group of affected species, which is hopeless. Realistically, we’re not going to be able to stop people using pesticides and honeybees, with their vast ranges, are going to be exposed to them. We have to make sure that the damage that does to them is as limited as possible.
It’s worth pointing out that we can all help with points 2 and 3 by being bee friendly gardeners!

*I hasten to add that the honey itself has no problem. Most of these nasties are fat soluble rather than water soluble, so turn up in beeswax and not honey.

Neonicotinoids again

I’m sure the various campaigns to ban neonicotinoids waged by people like Buglife, the Friends of the Earth and the BBCT are going to carry the day in the UK. I’m confident not least because they are backed by inceasingly persuasive science and, recently, Brussels. A number of retailers have started taking neonicotinoid based products like Bayer’s Provado off the shelves. Parliament’s Environmental Audit Committee is hearing evidence about them too.
Just as I thought neonicotinoids were about to get booted into touch in the UK, the agrichemical business is fighting a spirited rearguard action to save them. I wanted to pick up one point in particular from that, which I heard repeated again on the radio this morning by a man from Syngenta.

Foraging bumblebee
Stop!
Varroa has been a significant problem for honeybees. These are imported mites which attach themselves between the thoracic plates of honeybees and weaken the bees by sucking hemolymph. They also act as vectors for viral diseases. The European honeybee, Apis mellifera, has been defenceless against them. There are now treatments and ways of managing honeybee colonies which help the bees, and a lot of research is going on in this area.

The man from Syngenta said that bee losses were largely a consequence of varroa, not neonicotinoids. This is disingenuous. Recent research suggests the effects of neonicotinoids on honeybees are most marked when in combination with other problems, like the kind of viral diseases spread by Varroa destructor. The key point I wanted to make, though, is this. VARROA ONLY AFFECTS HONEYBEES. There is one honey bee in the UK. As I have blogged before, There are 26 Bumblebees and something over 240 species of solitary bees. Why are they declining? If it’s not varroa what is it? Some of the most persuasive recent research has looked at the impact of neonicotinoids on bumblebees. As for neonicotinoids’ effect on solitary bees (and butterflies, hoverflies, etc.), well… er… we don’t really know.

I did agree with the man from Syngenta when he said that banning neonicotinoids might not halt bee declines, and if it happens there’s a danger bees will disappear off the map of public awareness. There’s climate change, habitat loss, disease, new predators – all sorts of threats which still have to be dealt with.

Three Bees

There’s often general confusion between different types of bees, and I thought it might be helpful to clarify who’s who in a brief introduction. In the U.K. we have honeybees, bumblebees and solitary bees, and each are quite distinct. They all collect pollen (for protein) and nectar (carbohydrates) from flowers, but live in different ways and have different problems.

Honeybees
Bee_plants_crocusThere’s one species of honeybee in the UK – the European or western honeybee Apis Mellifera (Apis = bee, mellifera = honey producing).They can look darker or yellower, though, as there are different strains around. They are social bees, living in highly organized colonies of up to 60,000 bees, where they store large amounts of honey to eat throughout the winter. They travel up to 12km to find the nectar and pollen they need, and they forage in groups. Each colony usually has a single queen, who typically survives for several years. These are the bees we keep, and are most commonly mistaken for wasps.

Bumblebees
White-tailed_bumbles_sedumThere are currently 25 different species of bumblebee in the UK, although only 7 are common (including a recent import from France). Different species have different length tongues, adapted to collect nectar from different sorts of flowers; longer tongued bumblebees can access flowers honeybees and solitary bees can’t. People notice the queen bumblebees in particular, as they look for nest sites in the spring after hibernating or when the new queens fatten themselves up in the autumn (as in the photo). They’re big bees! Most bumblebees nest underground, often in deserted mouseholes or in places like compost heaps, and colonies are very small – only a few hundred. They’re not as well organized as honeybees and produce no food stores to over-winter on; the queens only last a season and the colonies break up in the autumn. They’re not as mobile either, and forage on their own over much shorter distances. They’re visually easy to distinguish from honeybees; they’re much furrier.

Solitary Bees
solitary-bee-3Astonishingly there are over 240 species in the UK. Hardly noticed, they go busily about the garden, typically nesting in the ground (mining bees), in wall crevices (cavity nesters) or in decaying wood (carpenter bees), according to the species. They can do well in the solitary bee boxes you can buy or make. They have relatively simple and short lives, which are concentrated on producing and safeguarding their eggs. These are sometimes protected with physical barriers constructed by the bees, typically made of mud or leaves – cut in neat half circles from plants like roses. We know remarkably little about solitary bees, which are thought to be the major pollinators of flowers in the UK. Oh, and they’re stingless.

Mimics
Hoverfly_Helophilus_trivittatus_asterThere are lots of flies which mimic all three types of bees for their own sometimes nefarious purposes. Hoverflies are often mistaken for them, but once you’ve got your eye in you’ll be able to see they fly very differently; hoverflies…er… hover.

Bee Problems
Honeybees, bumblebees and solitary bees have their own diseases and parasites, which are much more problemmatic when in combination with the issues below. The best known is probably the varroa mite, which has done terrible damage to European honeybee populations – to the extent that there are pretty much no wild colonies left in Britain. It is now treatable in the apiary, but colonies need careful monitoring.
There are a cocktail of other nasties which effect all bees more or less, depending on your point of view:
1. Habitat loss: there are fewer flowers around and fewer of the right sorts of flowers, particularly wildflowers. Bees also need a variety of pollen and nectar sources pretty much throughout the year, from early bulbs to winter flowering shrubs and trees. You can do your bit to help by planting some bee friendly plants, particularly those flowering outside the summer months. Different flowers are good for different bees; I’d recommend Plants for Bees as an invaluable guide.
2. Climate change: warmer winters mean bumblebee queens break hibernation and honey bees become active before spring – i.e. before there are flowers out. The queens use up their fat reserves too quickly and the honeybees their honey, so they starve to death. This can be the single biggest cause of honeybee deaths in a bad year.
3. Pesticides: This is the debate which currently causes the most heat and noise. We’re now using systemic pesticides, neonicotinoids, whose introduction in different countries seems to have coincided suspiciously with dramatic declines in bee numbers. As they’re systemic they effect any insect that feeds off treated plants, which unfortunately includes the insects feeding off the pollen and nectar these plants produce. There’s mounting evidence suggesting the damage to bees from them is significant.

Wild Bees and Honeybees

It’s been an eventful week on the bee front chez Mann. I’m without my honeybees as we’re still house sitting, so a friend is looking after them. I did bring a spare box with us though, which I used as a bait hive last year. I filled it with old comb and even sprayed it with a (French made!) pheromone aerosol to attract any passing swarm. It didn’t work then but it did this week, although it might have been more convenient if I hadn’t left it just outside the kitchen door! A local beekeeping friend was delighted to come and pick up the hived swarm, which seemed very well mannered. Hurrah!
Next to the bait hive my broad beans were being pollinated not by the honeybees, but by some friendly carder bees. It turns out that wild bees like this bumblebee are more important pollinators than many had thought. I’d been puzzled by this; you hear a lot about honeybee declines at the same time as the volume of crops grown in the UK requiring insect pollination is actually rising, as are yields. According to a study just released by the University of Reading (Pollination Services in the UK: How important are Honeybees? ) it’s wild bees wot done it:

The findings indicate that insect pollinated crops have become increasingly important in UK crop agriculture and, as of 2007, accounted for 20% of UK cropland and 19% of total farmgate crop value. Analysis of honeybee hive numbers indicates that current UK populations are only capable of supplying 34% of pollination service demands even under favourable assumptions, falling from 70% in 1984. Inspite of this decline, insect pollinated crop yields have risen by an average of 54% since 1984, casting doubt on long held beliefs that honeybees provide the majority of pollination services. Future land use and crop production patterns may further increase the role of pollination services to UK agriculture, highlighting the importance of measures aimed at maintaining both wild and managed species.

Sexing Up Scabious

Today we saw the latest Countryside Survey published, which is “a unique time series of data which incorporates measures of soil, water, vegetation and landscape made at the same locations in 1978, 1990, 1998 and 2007”, about which more anon. The report’s authors talk about “ecosystem services”, which I think is nice – “the potential of natural and semi-natural ecosystems to provide for human requirements both currently and in the future”. As they point out, it’s a bit vague, but the more we get used to ascribing an economic value to the environment the better. I can’t say I understand the Conservation Credit system, but isn’t something like it worth a try? A forthcoming UN Report,The Economics of Ecosystems and Biodiversity, is about exactly this topic. According to the Guardian:

In all, the report concludes, the world is losing natural capital worth up to £3 trillion every year – mostly due to deforestation, and far more than the one-off cost of the recent financial crisis.

The trouble is that the costs are invisible to conventional economics. “Not a single bee has ever sent you an invoice,” says Pavan Sukhdev, the banker who led the study. “And that is part of the problem – because most of what comes to us from nature is free, because it is not invoiced, because it is not priced, because it is not traded in markets, we tend to ignore it.”

The first step is to make the costs visible, he says, since “what isn’t measured, isn’t managed”.

So what was the main take-away from the Countryside Survey data? There was a significant decline in plant diversity – an 8% reduction in the number of species recorded from 1978 – 2007. Declines in nectar plant diversity were widespread across a number different habitats. The report sees this in the context of terrestrial plant species diversity reduction in the wider countryside, most of which “remains unexplained”. Gulp.

As a non scientist I have to think we don’t need to look much further when trying to understand the steep long term declines in populations and species of pollinating insects here. Caroline Spelman doesn’t have to travel all the way to Nagoya to hear about catastrophic, and costly, loss of biodiversity – it’s happening in her back garden at home.

Perhaps it’s just not sexy enough for people to be interested. In the absence of fetching pictures of large mammals, Press coverage of our domestic conservation issues seems to swing between the indifferent and the bizarrely alarmist. For example, I have seen the “crash” in our honey bee population ascribed to, variously, mobile phones, the wrong sort of bees, new pesticides, mystery viruses, and intensive beekeeping – which may or may not be contributory factors*. Sure, honeybees have their own specific problems, most notably the Varroa mite, but wouldn’t it be sensible to work to make people more aware of the long term problem faced by all pollinators here, rather than looking for the next “bee killer” headline? Even more frustratingly, this is something anyone with a back garden can do something about. And of course it’s not just the pollinators like butterflies and bees which are being affected; this plant loss will cost us all dear.

*It turns out honey bees have had rather a good year in the UK, by the way, according to the BBKA; mine certainly did much better, principally because it didn’t rain all summer. And don’t get me wrong, I’m certainly sympathetic to a couple of these issues. Oh, and incidentally, next year’s “bee killer app” will almost certainly be Asian Hornets. We’re all doomed.

Let’s Make Honey, Honey

I know there are a lot of beekeepers who read this blog, so if you’re one of them look away now! I thought it might be fun to post a few photos of the process of making honey for the non-apiarists though. I’m far from an expert beekeeper, although I’ve been keeping them more or less successfully from 2005. I’ve been on a couple of courses hosted by my local division of the BBKA, and picked up a lot from the beekeepers I know, but still feel I’ve a lot to learn. It’s a real art, and not something that can be learnt from books in a couple of years. We only have between 2 and 4 hives, but they seem to do well and I’ve developed my own style of looking after them. To be honest I’m more into the husbandry side of it than the honey production, but it’s still very satisfying turning up to dinner parties with a pots of honey, or selling them at the village fete. So, how do you get the honey into jars?
Homeward boundOur most successful honey producers this year started life in 2009 as a swarm from one of my friend’s hives, which I captured and hived. The photo shows the queen leading the swarm into their new home in May last year. The big box you see is mostly the “brood chamber”, which has vertical frames of wax “foundation” inside for the bees draw out into cells (beekeepers of old and many current apiarists don’t use these, but let the bees make their own wild comb). These will either be filled with eggs by the queen, or pollen or honey by the workers. When the colony starts to expand, in the spring, I put a metal grill “queen excluder” on top of the main box. Because the worker bees are smaller than the queen they can get through it but the queen can’t. On top of that I put smaller boxes, “supers”, with wax foundation. Because the queen can’t get to them to lay her eggs, the workers fill them up with honey. HoneyThe photo shows a super with a full frame. There’s a lot goes on over the summer, of course, which is for me where the fascination is, but if things go well you end up with a crop of honey to extract in early August. I take much less honey than many beekeepers, which means that I don’t have to feed the bees with suger syrup over the winter as they have more than enough by way of natural stores. Honey extractionThe first stage of the extraction process of the honey we do take is to get rid of the bees from the supers, which we do with a simple system of bee valves which let the bees in one way, down to the brood chamber, but not back up again. Once that’s done, we lug the boxes back to our honey extraction centre (AKA my office) where my glamorous assistant starts the process of decapping. Once the bees have collected enough honey in a cell they cap it with wax, which we remove with a heated decapping knife. Centrifugal honey extractorIt’s a sticky business. Once that’s done we pop the frames in our extractor, which works by centrifugal force; turn the handle, it whizzes the frames around three at a time, and the honey spins out onto its sides where it then falls in rich globs to the bottom of the tank. Next we filter it through a fine sieve into a settling tank overnight. Then, hey presto, Lamyatt honey, which we bottle in rather superior hexagonal jars. I was really pleased this year because I managed to make some squares of comb honey too in minute quantities, which has already been reserved for close family and those local friends with the best wine cellars. Whisper it not, but we’ve had our biggest year this year, and the honey is delicious. I usually make furniture polish or candles with the wax, but that’s another story. Before I do I have to treat the bees for disease and clear up sticky floors, sticky sink, sticky kitchen surface, sticky door handles, sticky…
Related Posts: Honeybees

Lavender

Bees in lavenderIf there is a better plant for bees at this time of year I have yet to see it. I took a rather wobbly video of the 8 metres of lavender hedge outside our kitchen this afternoon, which partly shows the concentration of bees on it. There must have been several hundred there. I could see some of my honeybees, four different species of bumblebee – Garden (Bombus hortorum), White-tailed (B. lucorum), Carder (B. pascuorum) and Red-tailed (B. lapidarius) – and two types of cuckoo bee, the Gypsy cuckoo bee (B. bohemicus) and the Field cuckoo bee (B. campestris). There were probably lots more I didn’t spot, in addition to various hoverflies.
It’s a particularly great garden plant though because it works so well for us humans; it’s a good hardy hedging plant, looks good, smells good, and has all sorts of medicinal and cosmetic uses. I have been digging around for a specialist supplier as we currently only sell a limited selection, albeit of really well priced and nice sized plants, and what better nursery to sign up than Downderry Nurseries in Sussex, Gold Medal winners at the Hampton Court Show. We will be launching our new range of specially selected cultivars next spring. Hurrah.

Our Meadow in July

Greater Knapweed clumpMeadow BrownOur meadow is lovely at the moment; although the most obvious flowers are Greater Knapweed, Yarrow and Meadow Vetchling, the Self-heal and Lady’s Bedstraw are also out. The meadow is alive with insects; it is buzzing and clicking, chirping and rustling. Fantastic. I thought I’d stand in a clump of flowering Knapweed (Centaurea scabiosa) for ten minutes in the morning and in the afternoon and see what came along. I’m no entomologist, so please excuse the identification, but how gratifying to see so many friendly pollinators. Nothing out of the ordinary, but a good crowd.There were, of course, many more, either too small or too fast for this useless photographer, Six Spot Burnetbut at least this gives an idea of what you might help with a small meadow area…
Greater Knapweed is one of the best nectar plants, and it seems to attract all sorts of pollinators. Most obvious were the butterflies (and day flying moths). We’ve once again been swamped with Meadow Browns this year, but in my half an hour I also saw a Six Spot Burnet moth and a Small Tortoisehell. I’m sure we’ll have Gatekeepers later on too. Although Greater Knapweed seems to be just the ticket for butterflies, it is more of a struggle for our honey bees with their much shorter tongues. Perhaps surprisingly they’re not dissuaded, Small TortoisehellHoney beeand in the afternoon sun were the most numerous insect about, with two or three simultaneously working the same patch. They were very specific in their taste, as were the Hoverflies; not for them Meadow Vetchling or Lady’s Bedstraw. The solitary bees I saw were the same. Much quicker and more agile than bumblebees, there must have been at least 6 different species at work, although I only managed to photograph three. I’m still hopeless with my identification;Large Solitary Bee and KnapweedSolitary Bee and Knapweed I think there were Mason Bees of various types and Leaf-cutter bees too. Since we made our solitary bee box I have become more aware of these chaps and, consequently, see many more of them about, but still struggle to work out who is who. There are, after all, over 250 species to get to grips with and they all move fast. More work required. I am marginally more at home with bumblebees. Solitary Bee and KnapweedOur garden and meadow areas have become Bumblebee Central, thanks to judicious planting and management. Although we have plenty of Common Carder Bees (below top left), I’m still disappointed not to have seen the Shrill Carder Bee, but I live in hope! I think I have also seen Brown-banded carder bees (Bombus humilis) about, but I couldn’t be certain. The other unmistakable bumblebee around at this time of year is the Red Tailed Bumblebee, B. lapidarius. There’s a nest under the orchard wall around 50 metres away, and it wasn’t surprising to see a few workers of this very smart Common Carder BeeRed Tailed Bumblebeeand relatively short tongued species around the nectar rich area where I was snapping. My identification skills start to go awry at this point, however. Apparently the key difference between B. hortorum, the Garden Bumblebee, and B. lucorum, the White-tailed bumblebee, is the yellow band at the bottom of the thorax. Tricky. I hope I’ve got this right. I think this is a White-tailed Bumblebee – i.e. without yellow band on thorax. White-tailed Bumblebee Common but endearing. This next lady, then, could well be B.hortorum, or a Garden Bumblebee worker. She is rather moth-eaten, but she does have a yellow band at the bottom of her thorax and, apparently, a very long tongue. If I’m lucky I can sex bumblebees, which you can do by looking at the antenna; long, round antenna mean a male. I might have some idea on bumblebee identification, but I know next to nothing about different hoverflies. I think I can only confidently name one of these. Like solitary bees I am astonished to find the vast number of native species – around 270 – Garden BumblebeeHoverfly 1and they are strong enough flyers that, like butterflies, we also entertain migrants. I’ve always been told their larvae have an insatiable appetite for greenfly, but it turns out that only about a third of them eat aphids. They’re interesting and attractive insects, though, and – surprise surprise – many are in decline as a result of habitat loss. I thought I’d add some to my gallery, as they frequented the Knapweed too. Hoverfly 2Hoverfly 4The meadow will start to look tired in a little while, and once some of the Knapweed goes to seed I’ll cut it. I don’t need the hay, so it doesn’t matter if it’s all stalky. The sheep are already running through some sections of it where there’s nothing left to flower to save me the effort of cutting it. In the meantime I’m looking forward to more coffee breaks out there in the sun, and enjoying it as much as the birds seem to be. Hoverfly 3I haven’t even begun to describe the Flycatchers, finches, martins and swallows… I’m just amazed by how much there is going on in such a small area, and equally amazed at how easy it has been to establish such a rich habitat. Immensely satisfying – go on, give it a go!

In Praise of Holly

Tree PeonyGiven that Somerset are playing Yorkshire at Taunton it seems unlikely, but I declare today to be the first day of summer. To mark it I’m going to write with apparent perversity about Holly. Wandering around the garden enjoying the warmth, this afternoon I was snapping brassy beauties like our tree peony, bought from Kelway’s Nursery, spiritual home of the peony and just down the road from us. I began to wonder though where all my bees were – that was until I came across our holly tree.

Despite it being pretty shaded it was jumping with them. As our tree is female it offers them no pollen, but its pretty little flowers must be a pretty good nectar source. It’s a favourite for the birds too – this one tree has had three nests in it this year, including one that was home to our lovely Mistle Thrushes.Female Holly My guess is that our native holly hasn’t been much planted of late. It doesn’t feature in commercial native hedge mixes sold by folk like us because it can’t be sold bare root. It’s too slow for most people to plant as a screen, and if you want a slow growing evergreen hedge then Yew is easier to grow and to manage – and it’s posher. Holly flowers are so inconspicuous most people don’t even notice them, and our berries get stripped by the birds before we can use them for Christmas decorations. It will be a shame if holly starts to get rarer; it’s not only a useful tree that grows in the darkest spots, but one deeply rooted in British myth and landscape.