It’s not just bees and butterflies on your flowers

Today we have a guest blog from Dr. Stan da Prato, a Keep Scotland Beautiful judge and editor of the Caledonian Gardener.

There is now considerable public support for our bees, and awareness they are in decline and that pollination services are important economically.  Garden centres regularly feature ‘bee friendly’ plants in their sales areas. Amateur gardeners are keen to do their bit. The good news is that most flowers are of some value to pollinating insects.  Avoid double flowers and some highly developed bedding plants – though don’t worry if you have a few e.g. double begonias in your hanging baskets provided there are lots of single flowers elsewhere.   Aim for as long a flowering window as possible which implies a wide range of plants.

Herbaceous plants with background of cat mint and Russian sage

It always interesting to look at other people’s gardens so when you are out for a walk look at what is in flower, grows well in your area and is attracting insects.  Talk to other gardeners, they may well be happy to divide their plants to give you some. Hardy perennials are easy to divide at the right time of year so you get plants for free. If there is a local garden club join it. 

Although honeybees get most of the credit, at least 1,500 insect species pollinate plants in the UK. Different colours, shapes and sizes of flowers tend to attract different pollinators. In the UK the majority of pollination is carried out by bees (wild solitary and bumblebees, as well as domesticated honeybees), flies (including hoverflies and bee-flies), butterflies, moths, wasps and beetles.  Bumble bees are important pollinators. They fly in lower temperatures than many other bees.  Their round, fuzzy bodies perform buzz pollination, when they grasp a flower   vibrating their wings to dislodge the pollen. Plants like tomatoes and peppers benefit from this. Many other plants are pollinated by shorter-tongued insects including honeybees and hover flies. Most fruit tree pollination is carried out by solitary bees and honeybees. 

Although attractive to us there are just 34 resident butterfly species in Scotland, compared to around 1,300 moths.  Many moths operate at night when they are attracted to pale flowers with a strong scent.   Beetles are attracted to flat, open flowers, which allow them to graze, such as cow parsley. Approximately a quarter of the UK’s beetles are pollinators, around 1,000 species. Some birds like the warblers will transfer pollen as they take insects from flowers. Abroad some plants e.g. fuchsias are pollinated by hummingbirds, but in this country they get by with insects. 

Native wildlflowers allowed to grow in grass

It not practical to give a full list of the plants that are used by pollinators as it would be so long ! Early flowers are especially valuable to us as well as wildlife. Ivy, many spring  bulbs, primulas and hellebores are all good. As the season  progresses a wide range of perennials come into  bloom. All the hardy geraniums are good with Rozanne one of the best due to its very long flowering season.   Particularly good for bees are the catmints  e.g. the vigorous Nepeta Six Hills Giant and Russian sage, Perovskia, an easy to grow lavender substitute. Annual mixes are cheap and colourful. Those containing cosmos have a very long season into autumn. In later years they often become less attractive to humans as thistles and docks take over so you may wish to resow annually. Sunflowers are fun for children to grow. Borage is an easy annual that bees love. By late summer there many good perennials such as asters, echinacea, rudbeckia and many more.   

An obvious late summer flower is the butterfly bush, Buddleja davidii. However this brings us  to an important point. Most flowers, even if not native wildflowers, will attract some insects. However the caterpillars or larvae are usually much more specialised and will only survive on a limited  range of  species, some on only one. Comma, peacock, red admiral and small  tortoiseshell  caterpillars will not feed on butterfly bushes but need nettles; only four of the 40 invertebrate species that need a plant many regard as a troublesomeweed.

In your own probably limited space aim for maximum returns. It’s easier to run a large garden  than a small one where you have to think more carefully about what to leave out!

Long flower annual mix

How about taking an interest in your local park or other public open space?  Here there is much more  room for planting but local authorities are all under financial pressure. They are likely to welcome input from local volunteers, especially for the fiddlier tasks – weeding is one! – which their staff don’t have the time to do. Do remember council managers will be concerned  that you may start a project but not keep it up so discuss this issue thoroughly at the start. It is easier to have wilder areas in parts of a park with native weeds/plants.  Note that rotting logs, and piles of stones, usually have more invertebrates than elaborate bug hotels though these can be useful educationally in school grounds.  Solitary bees – there are over 300 British species – can benefit from pieces of timber with holes drilled into them. 

It’s worth having a notice board explaining to the public what is happening so they don’t  presume the wilder areas are just about saving money.  

Letting  your lawn grow a little wilder has become popular though initial results can be disappointing as short grass becomes longer grass.  However, long grass can be food for caterpillars including the skippers and several  brown butterflies   No mow May has become a slogan but many would leave cutting into the autumn and, crucially, remove the clippings to reduce fertility. 

Crocus provide cheap and cheerful colour in early spring

It’s well worth keeping a record of your progress; easy nowadays with digital cameras and phones. 

More information can be found on the Butterfly Conservation, Buglife, Bumblebee Conservation and Plantlife websites. The RHS site has lists of pollinator-friendly garden plants.

Further information:

In his role as a volunteer for the environmental charity Keep Scotland Beautiful, Stan offers mentor advice, guidance and support to many communities across Scotland and writes a regular piece in the Beautiful Scotland and It’s Your Neighbourhood newsletter. To find out more about Beautiful Scotland and It’s Your Neighbourhood and how to join the family in 2023, visit www.keepscotlandbeautiful.org or email beautifulscotland@keepscotlandbeautiful.org

Images C North of Berwick in Bloom

Walk this way

In an afternoon in July a group met to walk along the Kinross Raingardens Trail. What they were going to see, and celebrate, was a fine example of the power of nature based solutions. Setting off from Kinross’s Park & Ride the group would look at a series of swales and wetlands designed to harness the power of nature to tackle an environmentally challenging issue.

Let’s pause for a moment. You might be asking yourself “What is a raingarden?” Had you asked the question during the walk the likely answer you would have received is that it is a collective term for various water management features, in its simplest form it is a planted area designed to accept rainfall running off adjacent land.

That’s a clear, if brief, way to explain what otherwise could be seen as a range of technical solutions comfortable with phrases such as enhanced extended detention basin, constructed wetland, infiltration basins; infiltration swales; permeable pavements, conveyance and biofiltration swales; hybrid hard/soft engineered permeable surfaces such as ‘grasscrete’. The user-friendly phrase raingardens neatly avoids the need to stretch for the nearest reference book.

Brian D’Arcy has been central to this project for several years now and recognises the dual task in front of him. The challenge at its simplest is how to use nature based solutions to tackle climate change issues such as flash flooding, whilst simultaneously explaining the techniques to a curious general public? Aided by an enthusiastic group of experts and volunteers alike he has done just that in four short, but hectic, years. The results are visually and environmentally impressive.

Nature based solutions of this kind are not a one-off, walk away, job done, fix. To imagine otherwise would be foolhardy. The walk explained that maintenance is required to ensure the effectiveness of the solutions. That’s something that has been grasped not just in Kinross but in smaller projects in outlying villages around Loch Leven such as Kinnesswood and Milnathort too.

Rain garden projects come in all shapes and sizes. 

Some notable projects have been delivered in partnership with local businesses such as the impressive willow swale at the car park edge of ‘Dance Connect’ in Kinross, and the wildflower plantings at ‘Kipper Hire’ in Kinross. 

Hungry diners can view retrofit planted channels and mini-basins in the car park at the highly popular Loch Leven’s Larder, whilst in Bridgend Industrial Estate gravel drains feature as part of a treatment wetland basin.

Shift along to the West Kinross Link Road and you can view an impressive detention wetland and street edge mini-swales (with short mown grass) all regularly viewed given that many people pass on their regular journeys. However, arguably the most visible project is the vastly improved Park and Ride facility in Kinross which offers much more for biodiversity than its predecessor managed. 

You could argue that the projects are at their most appreciated in a community setting, such as the ponds at three housing developments. Meanwhile a retrofit raised bed garden at Portmoak Primary school, and the‘ Natural raingardens’ at the lower end of overspill car parking in Kirkgate Park, catch the eye and give a growing sense that the approach is increasingly visible in the heart of local neighbourhoods.

For the projects to successfully deliver multiple benefits in different locations calls for a wide knowledge base. The key to harnessing that is partnership working. This draws  together those with expertise in delivering technical solutions and those with an environmental insight – such as the Tayside Biodiversity Partnership. 

This team work ensures that the community benefits from truly integrated and ‘natural’ solutions which deliver multifunctional benefits. All the retrofits have been working to reduce flood risks and most of the existing sites have dual function in the shape of water quality protection. However, there is a welcome and huge biodiversity bonus with the creation of wildflower and pollinator rich features in the townscape environment which just happen to visually enhance the areas for local people and visitors to enjoy and, as an aside, contribute directly to targets within the Scottish Pollinator Strategy.

Even something as apparently straightforward as reduced mowing regimes delivers reduced public expenditure on grass cutting, a smaller carbon footprint, and a haven for wildlife. In the wider sense the work here raises the profile of the necessity to embrace climate change mitigation measures now. 

For pollinators the work has certainly  been a real bonus. The projects use native vegetation, sourced from the highly respected Scotia Seeds (a recognised authentic native wildflowers supplier) in Scotland. These plants have lower nutrient requirements (and hence leaching losses) and lower watering requirements than conventional garden plants, which is all music to the ears of the project team. 

Other issues such as habitat fragmentation benefit from the  creation of ‘stepping stones”, which are a key part in producing healthy greenspaces for insects. It isn’t just the increased network of food sources that is good news, it’s the seasonal variety on offer too.

In 2020 the embryonic group had a goal to achieve 20 raingardens in the district, such was the zeal and enthusiasm that it had delivered that by 2021. 

Such startling progress clearly resonated with many.  Supporters include Scottish Government and SEPA, as well as Perth and Kinross Council. And to crown it all Kinross Raingardens won CIRIA’s ‘Community SuDS’category to scoop a prestigious national award. 

That’s quite an accolade. CIRIA is the construction industry research and information association, and within that body Susdrain is a respected community that provides a range of resources for those involved in delivering sustainable drainage systems to help to manage flood risk and water quality. It also makes no bones about the need to simultaneously improve biodiversity and amenity.

The raingardens challenge was designed to tackle issues ranging from regular flash flooding, biodiversity loss, quality of greenspaces, through to diffuse pollution from car parks, industrial premises and roads. The realisation that alongside technical solutions there was a need to navigate a clear path through language and communications was a vital component. 

So, should you take a stroll around Kinross, do look at the impressive raingarden solutions. The local community are rightly proud of the changes made at Portmoak Primary School, Kinross Park & Ride, Loch Leven Boathouse, and Kirkgate Park to name but a few. Each project is testimony to a group that can both ‘talk the talk’ and ‘walk the walk’. 

Images copyright and courtesy of C A G Lloyd

Apples forever?

By Athayde Tonhasca

In the 1800s, British people were familiar with the saying “eat an apple on going to bed and you’ll keep the doctor from earning his bread.” The advice was shortened into the form we know today: “an apple a day keeps the doctor away.” As often happens with popular lore, the maxim piqued the curiosity of doctors and researchers about the truth behind it. They gathered data to see whether there was an association between apple consumption and physician visits (Davis et al., 2015. JAMA Internal Medicine 175: 777-783), and the answer was no. However, the team found out that adults who eat an apple a day appear to use fewer prescription medications. So a more accurate, science-based maxim would be “an apple a day keeps the pharmacist away.”The result is not really surprising: fruit and vegetables are excellent sources of vitamins, minerals and dietary fibre; they reduce the risks of heart disease, digestion problems, stroke and some types of cancer; they also help in maintaining a healthy weight.

Foods rich in fibres: fruits, vegetables and grains © National Institutes of Health, Wikimedia Commons.

According to the World Apple and Pear Association, the UK produces about 190,000 tonnes of apples annually, but only 30% or so of the eating apples we consume are home-grown; we need imports to supply all of our apple munchers. Apples are the third most popular fruit in the UK – after citrus and bananas – but there is more to them than being a healthy snack: juice, puree, cider (an industry valued at £4.5 billion/year), jam and compote are important items in British pantries. The passion for apples is not unique to Britain; 85 million tonnes are produced worldwide, with an economic value of US$ 45bn.

The Fruit Market, by Giacomo Legi (1600?–1645?). Image in the public domain.

Of all variables affecting the apple industry, one is particularly finicky – the demands of an apple flower.

Most varieties of apple (Malus domestica) cannot self-fertilize; they need to receive pollen from a different variety to produce fruit. Wind cannot do the job, so apple trees rely on insects for pollen transfer. If flowers are not adequately pollinated, the resulting fruit may be misshapen. Not only that: poor pollination reduces seed set, fruit set and fruit weight, which is the most important quality for the market.

The European honey bee (Apis mellifera), solitary bees, bumble bees and hoverflies can all pollinate apples, although some pollinators are more efficient than others for some varieties and in some regions. Also, different pollinators complement each other’s work. For example, honey bees visit flowers in large numbers, but their activity is drastically reduced in bad weather and low temperatures. But bees such as mason bees, leafcutter bees (family Megachilidae) and bumble bees carry on, come rain or shine. Solitary bees in the genus Andrena emerge early in spring, thus start pollinating way before other insects are going about.

An Andrena sp. bee loaded with pollen visiting an apple flower © Sheffield et al., 2016. A Manual on Apple Pollination.

The overall picture emerging from an assortment of studies involving different apple varieties in different geographical regions is that the stability of pollination services depends on pollinator biodiversity: a range of bee and hover fly species is the best insurance for yields and economic profit. And it’s not just apples: some varieties of pears, apricots, blueberries, cherries, cranberries, peaches, raspberries, plums and many imported fruits also depend on insects for pollination. Recent events highlight the importance of not losing sight of these connections.

The Covid-19 pandemic has increased food insecurity in almost every country by reducing incomes and disrupting food supply. Food security, or people’s physical and economic access to sufficient and nutritious food, has been further endangered by the war in Ukraine. Few of us would have predicted that an isolated conflict in Eastern Europe could threaten several African countries with famine, reduce the supply of cooking oil in our supermarkets, or shrink crop production worldwide for the dearth of fertilisers. Terrible as they are, epidemics and wars can prompt us to consider the consequences of apparently loosely related variables such as declines in insects and human health.   

Christopher Coghlan (McGill University) and Shonil Bhagwat (University of Oxford) did just that: they estimated the drop of food production if there was a severe decline of pollinators (Global Food Security 32: 1000614, 2022). Although the authors considered a worst-case scenario, the results were worth paying attention to. Their analyses suggested that fruit supply in many parts of world would dwindle: losses would be above 80% in Britain.

Maximum decline in the production of non-citrus fruit. Percentage based on current production minus amount dependent on pollinators © Coghlan & Bhagwat, 2022. Global Food Security 32: 1000614.

A world without pollinators would be a world with no apples – or very expensive apples – and a scarcity of other fruits. ‘Hidden hunger’, which is a form of malnutrition caused by a lack of vitamins and minerals in the diet, would shoot up because many of these nutrients come from animal-pollinated plants. Non-communicable diseases such as obesity, cardiovascular disease, cancer and lung diseases would increase as well, with unforeseen consequences to global health. To make a bad situation worse, the world economy would be badly damaged, as more than 50% of exported crop products depend on pollinators.

Energy security, climate security and lunatic strongman security are constantly in the news these days; apple production security deserves a share of our attention.

Where dreams come true

To visit Clydebank’s Melfort Park is to glimpse the possible.  Not so long ago this was the site of a demolished school, out of bounds and rubble strewn. Fast forward to West Dunbartonshire Council accessing the Green Infrastructure Strategic Intervention Fund and you have a wonderful community park that embraces active travel, biodiversity, community growing and inviting green spaces.

But don’t just take my word for, Gillian Neil is the busy West Dunbartonshire Council biodiversity officer and knows the park and its aspirations well. Providing a better site for biodiversity was always a key target, but there is more to doing that than often meets the eye. It certainly isn’t a case of simply scattering bags of seed here and there.

From left to right: Andy, Gillian, Magda and Colin from West Dunbartonshire Council

“People might be surprised to learn that at Melfort Park there have been four different types of wildflower mixes planted on various plots, as well as some naturalised bulb planting,’” she explains.  “An early conversation for us was about how we establish wildflower meadows and what we were trying to create or replicate. That was an important discussion. Sometimes you are trying to create a nice pictorial meadow that is just lovely flowers and you get a great display every year. However, in some instances you are trying to recreate the good biodiverse elements which were previously there. Melfort Park posed a further challenge in that we had to protect the site against undue disturbance due the amount of asbestos found. To do this the site had to be capped which unfortunately meant the demise of the much of the existing vegetation which had lovely specimens naturally occurring on the brownfield site.  This included species such as kidney and common vetch, black medic and meadow vetchling. After the capping was complete, we brought in agricultural top soil, and it was that top soil which was then seeded with the four different mixes in four distinct plots.”

“We are about three years down the line now and some of the plots are being dominated by one or two species. Ordinarily with these kinds of meadows the traditional approach is that in the first couple of years you get them established, and look to supress anything that might become dominant. What happened here of course is that the Covid pandemic cut across all our normal monitoring and adapting opportunities in those early years. Following normal practices was impossible, which allowed some of the less desirable dominant plants to gain a foothold.

“Typically, the basic principle is that in the first year of a pictorial or wildlife meadow you sow a perennial mix with an added annual mix. In the first year the annuals show while the perennials are getting established. In the second year the perennials show better, although folk can feel a little disappointed as it doesn’t often match the first year’s bright and bold display. What you should do really is stick to a low sowing rate  – pictorial and wildflower meadows probably only really require just two to four grams per square metre – much less than in a normal grass mix. And if you go beyond this you don’t leave enough bare soil for the annual seeds to drop onto and germinate on for the next year. Many annuals are prolific seeders due to their short life span this is their reproductive technique, so you have to leave enough bare ground for contact to be made to continue getting annuals coming through in the subsequent years”

The team in West Dunbartonshire can now survey the site more regularly, especially this summer, now that things are normalised. This will allow two things to be measured. Firstly it will allow the team to see what has established that was in the original mix, and secondly to assess what has potentially come in with the soil that was that was brought in. Although councils tend to order sterile soil, sometimes this isn’t actually 100% sterile and surprises can emerge.  If it was purely a wildflower and grass mix then a subsoil substrate, rather than a topsoil, might work better as it is already nutrient deplete, which creates more favourable growing conditions for many of our native flora, as demonstrated by the broad range of species mix on the former demolished school site prior to the works. However, in this instance, we also wanted trees and some bulbs planted onsite too and they require topsoil.

“The other thing we will do,” explains Gillian “is establish if the right mix has been put in the right location. Although you can buy specific mixes off the shelf these days – like a wetland mix, or a pond mix — they might not always suit exactly the conditions you have on your own particular site. On reflection I’d say a site like Melfort Park probably needs an 80% grassland meadow with maybe 20% wildflowers coming through. But whatever your intentions and hopes, you have to be realistic about these things and accept that it can take several years to get your meadow right, and even then the job isn’t over, you need to keep on top of the maintenance. No meadow will be exactly the same from year to year. Ultimately what you have growing in year 5 will be substantially different to the mix you have sown as the annuals reduce in frequency and the perennials respond to the specific site conditions.

You have to continue to deplete the nutrients from the meadow until it establishes, otherwise the species which thrive on a more nutrient rich soil will dominate and you will lose your meadow mix. “To help us achieve our goals we have brought in a machine called a flail collector.  This basically connects to a tractor, and is run over the grasslands at the end of the season once the seeds have set, lifting the cuttings to be taken off site. The aim is to deplete the soil of nutrients, as native grasslands and wildflowers prefer nutrient depleted soils.”

Clearly it’s not an exact science creating a flourishing meadow. There is the issue of seeing if what you planned takes, agreeing on a mowing regime with the operatives,  and keeping a close eye on what is happening in case plans have to be amended. 

“We rely on a team effort to note anything gaining a foothold that ought not to be there,” notes Gillian, “In those cases we will have to cut on a more regular basis to keep some species in check.”

At the end of the day Gillian and the team can take comfort that what is happening is pretty much what was planned, despite the challenges.

Melfort Park is far better than just a bland rye dominated amenity grassland plot. That is something councils are increasingly trying to get away from. “If anyone asked me if what we have here is better than what was here before, then I’d say ‘Yes’. We can point to 40 or so species occurring now and there are wildflowers and native grasses and fescues over much of the plot. Sure we have to tackle things like docks and we also unfortunately have 1 plot with Horsetail, but those kind of challenges go with the territory when it comes to establishing a meadow.

“The general public response to Melfort Park has been overwhelmingly positive, Magda Swider, the regeneration officer in charge of the project, sought public opinion early on, and factored it into the creation of the site.  We listened to local voices when they said that they wanted some areas to be kept for general public use, so there are some flat areas of amenity grassland to provide somewhere easy for children to play, and for people to stage small scale events. But we also added the biodiversity, exercise and access elements that the public expressed a real desire to see here.”  Andy Devine, Greenspace Community Engagement Officer has had a large part to play on site especially with regards to the community allotment spaces which of course focus on growing, however, this has also made a considerable contribution as a wide variety of plants, fruit and vegetables which are grown onsite which not only is excellent for the local community, but the pollinators love the gardens too.

“Occasionally things don’t go right, you have to accept that, and adapt to meet those issues. We sought to include a lot of native grass seed in the grassland mix we used here on reseeded areas, mirroring what had been recorded here before. Originally the site had a good coverage of common birds’ foot trefoil, which is a prolific nectar provider as well as being a caterpillar food plant, alas in the meadow mix provided we found greater bird’s-foot trefoil instead, which I would more associate with a wetland environment.  This might seem like a small difference, but this species has a shorter flowering season than the more widely occurring common bird’s-foot trefoil and that matters in a biodiversity park.  It has established quite well now and I am also pleased to see the common version making a return as well.  It was a simple case of someone trying to improve an element but unfortunately in doing so perhaps losing sight of the better and key existing species. The lesson is to stick to the naturally occurring species if they are good. I often think that when you are trying to manage a site it pays to have a close look at what naturally occurs. However, on this site that was hard to achieve as we had to cap the contaminated parts of the site and bring in the topsoil therefore substantially changing the conditions for the existing species.  It will be interesting to survey the site over the coming seasons and keep an eye out for any of the original dormant seed stock that makes a reappearance!”

Undoubtedly Melfort Park is a big improvement for the local community.  For biodiversity, and pollinators in particular, a crucial follow up will be the ongoing overall management. There is something special about having such a rich biodiverse site in the heart of a town which had a considerable industrial footprint, and with the Greenspace team on the case it should stay that way.

STOP PRESS : Gillian was surveying Melfort in mid July with the local BSBI recorder Michael Philips, and Malcome MacNeill who is something of an expert in urban botany. They recorded 72 grass and wildflower species on the site.  It was particularly nice to record several native species that have now made their way on to the site that were not planted as part of the meadow sowing – lesser trefoil and black medic among them. There was also discussion of ideas on how to tweak the mowing regime to increase the habitat types within the park so safe to say Gillian is looking forward to seeing the progress over the next couple of years.

The unloved pollinators

By Athayde Tonhasca

When people are asked to list their most feared or reviled animals, sharks are almost invariably mentioned; snakes, wolves and crocodiles are other popular bogeys. These choices reveal a sharp dissonance with the real world, because sharks account for some 80 unprovoked bites per year, with about ten deaths: lightening is about 50 times more deadly. Wild reptiles and mammals are slightly more dangerous, dispatching an estimated 75,000 souls annually.

We may have nightmares about big wild beasts, but most of us are unaware they are small fry when compared to some of the Grim Reaper’s most efficient representatives: mosquitoes. 

According to the World Health Organization, mosquito-borne diseases kill around 725,000 people a year, some 600,000 of them from malaria. Dengue, West Nile virus, yellow fever, Zika, and many other pathogens and parasites transmitted by mosquitoes add to the vast numbers of people killed or debilitated, mostly children and the elderly in developing countries.

Zika virus information © World Health Organization.

Considering the magnitude of suffering, let alone the economic and social impacts of mosquito-borne diseases, nobody could be blamed for wishing mosquitoes to disappear from the face of the Earth. And with today’s knowledge and technology, a mosquito wipeout is not farfetched. Large-scale programs of genetic manipulation, male sterilization, bacterial infection or another technique could do the trick.

The question is, should we have a go at getting rid of mozzies?

There are more than 3,000 species of mosquitoes (family Culicidae), and most of them go about their lives feeding on nectar and other plant substances, never getting even close to humans or other animals. Only 200 or so feed on people, and a handful are responsible for the spread of diseases: mostly species from the genera Aedes, Anopheles and Culex. 

So, eradication schemes would likely sweep away innocent bystanders, which comprise the majority of mosquitoes. And there could be consequences. Mosquito larvae and adults are food to dragonflies, tadpoles, some turtles and fish; adults are also eaten by bats and birds. In the Arctic tundra, the Biblical numbers of mosquitoes during summer are a significant menu item for migratory birds. But ecologists debate the importance of mosquitoes as a food source: some maintain that bats, fishes and birds would decline sharply, with reverberations along the food chain; others believe that mosquito eaters would adapt and switch easily to midges and other insects.

Mosquitoes are considered mostly nectar thieves, that is, they take nectar without transferring pollen between flowers. But as improbable as it sounds, some of the pesky creatures pollinate. The blunt-leaved orchid (Platanthera obtusata) and the Northern tubercled bog orchid (Platanthera flava) give off faint mixtures of scents that some Aedes mosquitoes find irresistible. When a mosquito sticks its head into these orchids’ flowers, it may come out with a pollinium (a bag of sticky pollen) glued to its head. The pollinium can be almost as big as the mosquito’s head, so it’s surprising that the reluctant pollinator is able to fly away. Both orchids are pollinated by moths as well, but mosquitoes seem to be their main pollination agent. 

Left and bottom right: male and female Aedes aegypti probing the flowers of a blunt-leaved orchid. Top right: A pollinium attached to the eye of a mosquito © Lahondère et al., 2019. PNAS 117: 708-716.

Other orchids are mosquito-pollinated, and probably several more plant varieties are too. Culex pipiens and related species contribute to pollen transfers for tansy (Tanacetum vulgare) and other members of the Asteraceae, and for the aptly named mosquito flower (Lopezia racemosa) and Spanish catchfly (Silene otites). Aedes spp. helps pollinate the white mountain-avens (Dryas integrifolia).

The mosquito flower © Juan Carlos Fonseca Mata, Wikimedia Commons, and the Spanish catchfly © Stefan.lefnaer, Wikimedia Commons: two plants benefiting from mosquitoes.

Evidence for mosquito pollination is often circumstantial but credible. Field collected specimens can be loaded with pollen grains, at levels comparable with moths and butterflies.

a. A pollen-carrying male Culex tarsalis from inflorescences of tansy; b. A pollen-carrying female C. pipiens collected from inflorescences of Achillea millefolium © Peach & Gries, 2016. Arthropod-Plant Interactions 10: 497-506.

What would happen to those plants in a world without mosquitoes? It’s impossible to say. They could get by with the help of alternative pollinators or by self-pollinating; their populations may hang by a thread; or they may go extinct. If we ever have the wherewithal to eliminate mosquitoes, we will need to ponder the balance between deliberate species extinctions and sparing millions of human beings and animals from death and sickness. The question will keep many a moral philosopher awake at night.

Conference highlights

Our Second Annual Pollinator Conference proved a big hit in mid-June. An array of excellent presenters provided a fascinating insight into work of busy community groups on behalf of pollinators from Caithness to Glasgow, Dundee, Stirling and finally Turin. 

The aim of the conference, which Keep Scotland Beautiful promoted via their extensive ‘It’s Your Neighbourhood’ network, was to share good practice from existing projects, and offer support and encouragement to communities contemplating doing their bit for pollinators in their own local greenspaces.  

Nature Scot’s entomologist Athayde Tonhasca provided a highly engaging and extremely relevant scene setter on pollinators, looking at the range of species, their needs, and simple actions which could help improve the fortunes of pollinators.  It was the perfect way to summarise the purpose of the conference and ease us into the subject matter.

Enthusiasm, and perseverance, dominated the gathering and Scott Shanks demonstrated how Glasgow’s Yorkhill Green Spaces (a recent winner of our Keep Scotland Beautiful Pollinator Friendly award) certainly thrived on this recipe.

In a talk entitled ‘Making Space for Pollinators in Yorkhill’, Scott showed how three parks in this area, almost adjacent to the River Clyde, had ultimately offered a huge resource for pollinators and people. The work of improving greenspaces was fuelled by volunteers, and their activities ranged from sensitive planting, to long term management and included monitoring and educational activities.

Overnewton, Yorkhill, and Cherry Parks should all anticipate increased visitor numbers on the back of the wonderful slides that Scott shared. And that won’t be an entirely new experience, as Scott revealed that the sites drew considerable numbers of additional visitors throughout the recent COP26 event.

Scott’s approach was studious and targeted, covering a range of important issues for pollinator progress.  He outlined what pollinators needed from an urban greenspace (covering flower rich habitats, through to breeding and hibernation sites, and the avoidance of any pesticides). The determination to approach spring, summer and autumn with a continuous supply of pollinator food sources was also well explored.  The practical challenges of converting amenity grassland into wildflower meadows was covered, and the ongoing management requirements, particularly in an urban setting, featured heavily. 

As Scott moved towards his conclusion he pointed to the benefit of creating ‘stepping stones’ for pollinators. It was a wonderful (and colourful) insight on a range of magnificent approaches being taking in Glasgow.

We then moved on to Highland Council’s Paul Castle highlighting a most impressive long-term project on the north coast of Scotland at Farr Glebe in Bettyhill.

Paul is a Countryside Ranger in North Sutherland and North Caithness and brought bags of experience to his presentation – he has been involved in helping pollinators in his patch since 2006. His presentation revealed how, along with inspirational figures such as Murdo MacDonald and a range of willing partners, he had been able to oversee the pollinator-friendly transformation of a patch of land behind the Strathnaver Museum which is now well known as Farr Glebe.

With excellent support from the local community Paul was able to expand on how the patch of land is managed and he was at pains to stress the value of good interpretation in raising understanding of the issues and encouraging community involvement. 

The important issue of removing cuttings if an established meadow is to thrive was given a deal of attention by Paul and in this regard he was quick to acknowledge the sterling support of many local volunteers.

Some of the detail Paul revealed was fascinating. He highlighted how species like greater knapweed and field scabious – which are present at Farr Glebe – are actually quite uncommon locally. An undoubted star of his patch was the elusive Great Yellow Bumblebee. The role of organising events such as bumblebee safaris and benefitting from a close connection with the local museum emphasised the strength of partnership working and sheer drive on Paul’s part.

The contrasts, and similarities, between the presentations featuring Bettyhill and Glasgow were clearly appreciated by those looking on.  The shared goals, the varying challenges and the geographic differences all made for a good session when it came to comparing and contrasting methods and hurdles.

A cross-city approach was the theme of Catherine Lawson’s excellent summary of the work of Bonnie Dundee. Partnership working lay at the heart of a project that not only covered community gardens, but embraced allotments, schools, the council and Dundee’s Botanical Gardens. 

The group were embracing a city-wide approach and there was admiration for the variety of sites covered and the personal touch of reaching the community with seed packs. 

Those ‘Seeds of Hope’ and a strong presence at a host of events meant that Bonnie Dundee was well known in the city, and thus able to make an impact across a variety of communities. Again the value of interpretation to explain new management practices in greenspaces, and to engage the public with the species and habitats around the city had a big impact.

Leigh Biagi took us through the work of the highly respected and increasingly recognised On The Verge project. The Stirling-based group has gone from strength to strength on a philosophy of identifying patches of verges and under-used strips of land and converting them into floral resources for pollinators. 

People are crucial to the success of community groups, and all of our presenters displayed healthy levels of persuasive and passionate arguments. This was particularly true of Leigh’s approach which was laced equally with innovation and determination. The growth of a small local movement, into something increasingly gathering admiring glances nationally, is testimony to the desire and drive Leigh’s brings to her work and her excellent talks.

Topics covered ranged from the challenges of annual versus perennial flowering plants and the rewards of being fleet of foot when seeing an opportunity. The images shown spoke volumes for On The Verge’s achievements, and the ringing endorsement for the group from the likes of Professor Dave Goulson were testimony to the group’s reach and success.

With mirror-image groups now sprouting up in Cambridge and Surrey it is clear the On The Verge had adopted a model that is both effective and transferable.

We were delighted to be joined by Francesca Martelli who rounded off our presentations by giving us an inspirational run through community involvement with greenspace regeneration in Turin. The focus here was again multi-pronged and the mental health and physical well-being of participants merged with pollinator needs in projects designed to help nature and people in the ‘Fiat City’. 

Francesca’s work is again a wonderful advert for collaboration and partnership and the way in which swathes of former industrial wasteland had been harnessed for people and nature was an inspiration.

The Turin work sits to some extent under the umbrella of proGIreg work (a green infrastructure initiative) which is an EU project in urban areas often using co-designed pollinator gardens and infrastructures whilst emphasising the value of citizen science in species monitoring and the benefits to our own health and well-being.

That theme of post-industrial regeneration and the role of Nature-based solutions took us on a journey through parks and green spaces in Turin. Community and pollinator gardens complemented green roofs and raised beds in a flurry of activity carefully designed to benefit people and pollinators. 

Green corridors leading into the city centre and the involvement of disadvantaged families and Mental Health patients revealed both the value to communities and individuals as well as a nature dividend.

So an inspiring conference, with quality presentations from start to finish. It was with a sense of ‘things can be better’ that we drew the conference to a close.

Stay in touch:

You can follow the work of our presenters across various social media and digital channels.

Yorkhill Green Spaces on twitter @yorkhillgreen

Farr Glebe on facebook

Bonnie Dundee are on facebook and Instagram https://www.instagram.com/bonniedundeebloom/

On the Verge on facebook and webpages @ www.facebook.com/OnTheVergeStirling  &. https://www.onthevergestirling.com

Pollinators and people in the city of Turin are on the web, facebook and Instagram @ https://progireg.eu/   https://www.facebook.com/proGIreg    https://www.instagram.com/progireg/ . Turin’s Farfalle in ToUr