Neonicotinoids And Bees (Again)

Yesterday I saw two papers on neonicotinoids and bees. They are the first large scale look at how these systemic pesticides affect bees in the field.
We’ve known for some time that neonicotinoids have bad effects on bees in the lab, which is hardly surprising. They are pesticides, after all. The big argument has been about how they affect bees in the real world.

neonicotinoids
Oilseed Rape
The Centre of Ecology and Hydrology (CEH) looked at honeybees, bumblebees and solitary bees. Their paper aimed “to quantify the impact… of two commercial neonicotinoid-based seed treatments in commercially grown crops of oilseed rape”. As usual, the results the results have thrown up more questions. People will continue to argue about methodology, I’m sure. In essence, however, the conclusion is that the neonicotinoids harmed both “wild bees” and honeybees.
Ironically, Syngenta and Bayer funded the study. It was their neonicotinoids which were used. Led by the unfortunately named Dr Schmuck, Bayer CropScience are now scrambling to re-interpret the results and are adamant they are not conclusive.
A second paper, however, published in Canada, reached similar conclusions. It looked at neonicotinoid treated maize and honeybees. It has more bad news, as Buglife point out:

The Canadian study also found that the common fungicide boscalid almost doubled the toxicity of neonicotinoids to bees. This is significant because a recent paper showed that 70% of the plants that people buy from garden centres to help garden bees contain neonicotinoids, and 48% also contain boscalid (Lentola et al. 2017). This suggests that gardeners may be unknowingly poisoning pollinators in their efforts to try to help them, a factor that may be associated with recent declines in numbers of urban butterflies (Dennis et al. 2017).

We knew how toxic the combination of insecticides and fungicides is to bee colonies. This first came up when scientists were looking at Colony Collapse Disorder in the U.S. Now we can worry about the scale of the problem.

Three things have continued to irk me throughout this shambles. Firstly, we still know nothing about how these pesticides affect other pollinators. Secondly, what are the less damaging alternatives to neonicotinoids? Farmers claim they would have to use lots more pyrethroid based pesticides to control, for example, flea beetle. Conservationists claim they wouldn’t.* Why is this debate STILL going on? Let’s have some fact based policy! And this take us to the third point. Why have we been using these pesticides for so long without knowing what damage they might be doing? We are supposed to follow the Precautionary Principle. Instead, we seem to chase short term financial gain. Our environment is too precious to turn it into a kind of giant chemical experiment.

*no prizes for guessing where I stand on this one.

Tree Bumblebees

Tree bumblebees, Bombus hypnorum, were the main topic of conversation on the Bumblebee Conservation Trust stand at RHS Chatsworth last week. I last blogged about them in 2013, but it seems there’s a need to get more information out!

Bombus hypnorumBoth the BBCT and the BBKA (the British Beekeepers’ Association) are swamped by people asking for help with honeybee swarms, which turn out to be Tree Bumblebee nests. I get calls here too as I’m on the local swarm collection list. As the name suggests, Tree Bumblebees nest… in trees. Failing that, birdboxes or small holes in eaves make lovely snug nests for them. This is unlike our other bumblebees, which nest underground. It’s also unlike honeybees, which need bigger spaces to make colonies in.

It’s unusual for a bumblebee, and its behaviour fools many. Tree bumblebees are new arrivals, driven here by climate change around 2000/2001. They’re thriving, and are now one of the “big eight” of common bumblebees in the UK. Combine this with the cloud of drones which whizz around outside the nest entrance, and their habit of nesting in more obvious locations, and lots of people reach for the phone.

Please don’t! A honeybee swarm is quite different. The bees look very distinctive and there will usually be many, many more of them. Tree Bumblebees might look black from a distance, but they are actually a very smart brown, black and white. Like all bumblebees, Tree Bumblebees will nest for a season, so they’ll only be a temporary nuisance if they’re in the way. And they’ll help pollinate your fruit and veg!

Nigella Lawson in The Garden

For my sins I have spent several hours recently tramping around local estates delivering election leaflets. This has provided a fascinating insight into the average local garden. The real ones – not like you see on Gardener’s World or the Chelsea Flower Show.

I make this distinction because gardening seems to be treated by the visual media like cooking. Millions of people love to watch cookery videos but live on take-aways and fish fingers. Millions love to watch Monty Don and his dog but have urban gardens full of rusting barbeques and decking.

So what does Monty think his typical viewer’s garden looks like? I assume he’s in the same bubble as the celebrity cooks, so he’s going to be well wide of the mark. Well, at least in this part of the world, they generally don’t look great.

They fall into four groups:

1. Immaculate. Unusual. Typically heavy on the veg and cut flowers, head gardener of pensionable age.

2. Struggling. Possibly aspiring to immaculate but time and knowledge poor. Some weird sights. Gnomes.

3. Jungle. Lost engine parts and bits of recycling the foxes have messed about with. The odd child’s toy.

4. Hard landscaping. Cars on breeze blocks. Marestail the only green thing.

In total, not very encouraging for Monty – or for wildlife.*

A balance between 1 and 3
Firstly, jungle is – contrary to popular belief – not great for invertebrates. I aspire to a balance between 1 and 3. This combination was almost non-existent, interestingly. My favourite garden was one which had a kind of delicate urban meadow going on, with Fox and Cubs and Trefoil in the lawn. Judging by the veg, here was a competent gardener, but one who could give nature a nod with an aesthetically pleasing and time saving feature.

Secondly, jungle is mostly the look of rented houses and – consequently – becoming more and more prevalent. Why on earth should young renters bother?

Somerset MeadowThirdly, the more modern the house the more miniscule the “garden” and the more aggressive the hard landscaping. This is appallingly obvious, not the least because of the almost complete absence of pollinators in recently built areas. And these are areas surrounded by “countryside”.

So I took myself off to the local meadow by way of an antidote. Even here there seemed to be fewer bees than there used to be. Maybe the cold spring has been hard for them. Oh well. Here’s a nice picture of an orchid from the meadow anyway; Monty – or Nigella for that matter – would be pleased.

*Talking of which – people! – go easy on the damn slug pellets!

Seeding Wildflower Meadows in Spring

Thank goodness we have done no wildflower seeding here this spring. It has been so dry the patch of unruly wasteland we have in Somerset looks more like the Gobi Desert. I have been watering our green roof and running around the veg patch with a watering can.

I fear this is going to be a pattern; a dry spring followed by a cool wet summer. This is hopeless for seeding wildflower seed mixes. Wildflowers and native grasses are particularly vulnerable because – unlike commercial cultivars – they take a while to get going. They’re also surface sown rather than drilled, which leaves them exposed.

If there’s enough moisture around for seed to germinate the seedlings will conk out before you’ve even noticed them. If there isn’t there’ll just sit there being eaten by birds and blowing about until a downpour washes them away.

Traditional wisdom is that you sow wildflowers in spring or early autumn. Most of the species in wildflower meadow mixes set seed in summer, so you would think early autumn would be a better bet for seeding – and you’d be right.

Fingers Crossed

The idea with seeding in September is that the soil is warm and moist enough and the days long enough that there will be some germination before it turns cold. The caveat to this is to be wary of heavy wet soils, where there is a risk seed will just sit in waterlogged conditions and rot. There’s also a risk of a really wet and cold period on any soil, which would do for a lot of seedlings. Generally, though, it looks to be better time to seed than spring as rainfall is more reliable in September/October than it is in April/May.

Some species too, most notably Yellow Rattle, need to stratify to germinate, so want the cold of winter.

The text books say the last time to seed in spring is end May. This is particularly true of annuals, which won’t have the time to flower before the days start drawing in. If you’re sowing a mix of perennials and grasses – a wildflower meadow mix – I’m increasingly thinking you should think about doing it at any time of year between March and November when conditions are right.

We need to adapt to changing weather patterns and local conditions. If I were seeding a Welsh hillside I would be reasonably happy doing it in June, for example. Rainfall is pretty reliable throughout the summer here. On the other hand I’m increasingly cautious about sowing wildflower mixes in places like East Anglia and Kent in spring without the ability to water.

It looks like we’ll have to take more care whenever we seed. We should also resign ourselves to more failures because of hostile weather conditions. If you have to seed in spring water the seed bed then the seedlings.

Hooper’s Hedgerow History Hypothesis

Max Hooper has just died. He was a proper botanist, who became known because of his work on British hedges in the 60s. From the obituaries and his writing he seems to have been quite a character too.

Hooper's Rule

Like many I came across him because of “Hooper’s Rule”. This was his rule of thumb – for obvious reasons not definitive – for dating hedgerows. Walk along a 30 metre length of hedge and count the species in it. Multiply that number by 100 and you have a reasonable estimate for the age of the hedge.

There was also his work on the extent of the hedge loss in the UK. Hooper uncovered it by looking at RAF reconnaissance photos. 50 years ago we were losing over 10,000 miles a year. 10,000 miles! I didn’t think we had that many hedges – and how could we continue to be so casual about them?

I was staggered by Hooper’s Rule too. I started looking much more carefully at the hedges around our house in Somerset. All around us were early medieval hedges. Given the history of the village this was entirely predictable, I suppose, but I was amazed. Amazed that I hadn’t stopped twice to think about these important ancient things. Amazed that their diversity and history went unnoticed, at best. I then realised the hay meadow next door was probably pre 15th century. It was suddenly obvious to me that we didn’t even begin to appreciate or understand what was underneath our noses.

Realizing this and the extent of the destruction to our environment still going on was an important part of my decision to leave the City. There were much more important things to do. I started a business promoting – among things – native British hedge plants.  Thank you for helping to convert me, Dr. Hooper.

Adder Bites Man

I shudder when I read an adder bites man story. The Daily Mail couldn’t resist the temptation to sensationalise this extraordinary tale, although to be fair it did point out the last death from an adder bite in the UK was in 1975.

It’s an extremely rare event – rare enough that it gets plastered all over the National Press when it does happen. Adders aren’t easily provoked and they’re not “common throughout mainland Britain”. Far from it. Finding one in London is extraordinary. They’re pretty much restricted to some areas of southern England, Scotland and West Wales. Why? Loss of habitat but also persecution.

I shudder about stories like this because they provoke hysterical reactions in people. We have a lovely big grass snake in the garden. They’re clearly not adders, but people cheerfully chop grass snakes’ heads off because they’re scared of them. I’ve even seen people take spades to slow-worms because they thought they were adders. Yuk.

Slow Worm
The Gardener’s Friend

For the record, it’s illegal to kill slow-worms, grass snakes and adders. And people should think better of them. Slow-worms are fantastically helpful around the garden (and not snakes anyway). Adders kill small rodents, and with grass snakes are indicators of healthy ecosystems. I’m not thrilled by the idea of our grass snake eating our frogs and newts, but I am delighted we have so many it can.

Native And Exotic Plants In The Garden

Robin Lane-Fox wrote a bad tempered piece in last weekend’s FT about “exotic” v. “native” plants in the garden. He’s a respected plantsman, and so I wasn’t surprised to read he was against using native plants in the garden. I’m entirely sympathetic to this view; we are all masters and mistresses of our own gardens, and should do with them whatever we most enjoy. What did surprise me, however, is that he repeated the mantra that our wildlife was oblivious to the difference between (plain) native plants and attractive exotics. It’s true that disease threatens many of our “native” tree species. Sadly we would do well to think about alternatives for planting schemes. When we do, it would also be advisable to source them from UK nurseries so that a raft of new diseases doesn’t reach our shores. Improved biosecurity and more UK grown plants may be rare Brexit dividends.

Plants for Pollinators
It’s also right that “exotic” plants can be at least as beneficial to some wildlife as “native” plants – in some cases more so. Many bees, butterflies and other pollinators benefit from the longer and different flowering periods. There’s also the heavy nectar production of some attractive exotic flowers. We sell a fantastic seed mix from Flowerscapes which illustrates this. However – and this is a big but – it’s wrong to think of plants purely as providers of pollen and nectar. Even if we did there are bee species which are oligoleges – i.e. they feed from a specific plant genus or even single plant species.

Plant Food
I imagine there are no Brimstone butterflies in the doubtlessly beautiful Lane-Fox garden. Brimstone larvae dine exclusively on the leaves of one of our dullest looking shrubs, Buckthorns*. Many moth and butterfly larvae have similarly exclusive or nearly exclusive relationships with other native plants as do many thousands of insects. This includes the Blackthorn so disliked by Mr Lane-Fox.  Quercus robur – that’s the English oak, not your imported tat – supports up to 400 different species of herbivore insects in the UK. This kind of dependence is true of amphibians and mammals – no boring old hazel, no boring old dormice.

My own garden is less ornamental and more nature reserve, but that’s what gives me pleasure. It’s a smorgasbord of natives and exotics, vegetables and fruit trees. It’s also full of the munching, buzzing, swimming things which can’t survive in the surrounding farmland.

*Our bees also seem very partial to Purging Buckthorn‘s inconspicuous little flowers.

Garden Flowers For Bees

Perfect For PollinatorsWhen people ask me to recommend garden flowers for bees I usually point them at the excellent Plants for Bees by Kirk and Howes. Like most of us, though, I often wander through the local garden centre to buy plants for the garden. I try to buy flowers which are good for bees and other pollinators. I had thought that the RHS “Perfect for Pollinators” badge was a definitive guide to help me. Not so, apparently – nor are a number of other similar schemes and labels.

A study has just been released by the excellent Laboratory of Apiculture and Social Insects at Sussex University. They spent time in local garden centres where they found that “there were many recommended varieties that were unattractive or poorly attractive to insects, and some non-recommended varieties that were very attractive”. The report also points out the difficulties of recommending many different varieties and hybrids in the same plant group, many of which have misleading pictures on their labels.

Poor for bees and pollinators
No Thanks
I was aghast, to be honest, although it did confirm what I had suspected for a while. How can you say that two wildly different cultivars are both as attractive to pollinators? It explains why some “bee friendly” of “butterfly friendly” flowers in our garden here have disappointed. Roses are a very good example; the open single types of rose – closer relations to wild roses – are very different and much better for pollinators than the popular modern “English Roses”.
Dog rose - bumblebee
Yes Please!

So what’s the answer? The study suggests seeing which plants at the garden centre insects and bees visit most, which seems good advice. Ask yourself too how any self respecting pollinator is going to access the nectar and pollen of the flower you’re looking at.

The labels are a guide but nothing more.

Pruning Old Apple Trees

It’s the time of year to prune apple trees. We used to have an old orchard, and I loved renovating the apple trees there; it was amazing to see them springing back into life with renewed vigour. They must have been around 80 – 90 years old, so towards the end of their time, although pruning will extend their lives. This is one of the reason why orchards are such good habitats. Apple trees don’t last long, so there is always lots of dead and rotting wood around, with their attendant flora and fauna.

There are several reasons to prune, which you should bear in mind. Firstly, remove badly placed and rubbing branches, which can be an entry point for infection. Then think about increasing the light and air flow through the tree, to reduce the risk of infection and help apples ripen properly. I also cut out diseased wood rather than spraying a tree with fungicide to help biodiversity. You also want to manage the tree’s shape so it doesn’t blow over or risk losing major limbs in windy weather.

I was always told not to be frightened of taking too much off an old tree – up to 25% as a guide is fine – and to concentrate on taking bigger branches off to reduce the number of wounds. An old apple grower in Kent used to say a well pruned tree was one you could throw your hat through!

The chances are good that when you renovate an old orchard you’ll find heritage apple varieties. Many have only gone out of fashion because they don’t keep, bruise in transit or look asymmetrical. Think about grafting from the cuttings, to perpetuate part of our rural heritage.

If you would like to know more about pruning have a look at this helpful video introduction from the People’s Trust for Endangered Species – big orchard fans because of their importance as a habitat for so many rare flora and fauna.

Bees and Warm Wet Winters

My poor bees are having another terrible winter. “Terrible” winters for honeybees are warm and wet, not cold, which they can deal with quite happily.
If it’s consistently warm and wet they’re in trouble. They are too active, eating their winter stores of honey too quickly. After a while they starve, which is why beekeepers “heft” their hives – to feel how heavy they are, to assess how much honey is left in them. If not much they can be fed fondant to keep them going.
Better though would be to give the bees nearby forage, so that on dry days at least they can get out and bring some food back to the hive. We have some “trees for bees” on our website, which can help. It’s also worth thinking about early flowering bulbs like crocuses.
This pre-supposes that dry winter days are also warm, which isn’t what’s happening in Somerset at least. It’s either warm enough for the bees to be active but too wet for them to fly or sunny but colder. Grrr…
Bumblebee queens are only slightly better off as they can fly in lower temperatures and in drizzle. They will break hibernation on a warm day. I’ve seen queen wasps, which follow a similar life cycle, as recently as the last frost. I can guarantee low Social wasp populations here next year already.

European and Asian Hornets
Which is European?
These warm wet winters bring another ill for honeybees. The Asian hornet, Vespa velutina has reached these shores. It is an aggressive animal and a voracious predator of honeybees. Without colder weather it will spread rapidly and spell disaster for unguarded colonies.
I also fancy it is very bad news for our own European hornet, which is a relatively harmless* but much persecuted and increasingly rare beauty. Many more will now be killed, through paranoia and mistaken identity. Gone from our gardens will be their lovely baritone buzz – another victim, in a way, of climate change.

*not what I felt when I dried myself off after a dip on holiday last year with a hornet tangled in the towel – OUCH!