Tag Archives: pollination

On food, pollinators and what makes me scared (guest post by Maria Schewenius)

A long year ago and a few thousand miles away, I enjoyed my first lovely home-cooked Swedish meal in my then new friend Maria Schewenius’ flat, barely a week after I had flown there to start my sabbatical. Along with the moose patties and potatoes,

A traditional Swedish meal on Maria's balcony

A traditional Swedish meal on Maria’s balcony

the delicious meal Maria whipped up also included a salad featuring the freshest of tomatoes,

Tomatoes

Fresh tomatoes growing on an urban balcony

basil,

Basil, fresh as it gets

Basil, fresh as it gets

and other herbs

Herb garden in the balcony

Container garden full of herbs

Herbs in the balcony

Herbs and flowers

grown organically right there on the relatively small balcony of her (4th floor, if I remember correctly) flat!

Maria is a young urban ecologist working with the Stockholm Resilience Center on a number of projects of global import, including the Cities and Biodiversity Outlook (in which I played a small part) and URBES, among other things. As evident from the above photos, she is also an avid gardener, creatively making the most of the little open space and the few long days of summer sunshine available to her in the suburbs of Stockholm. Lovely flowers brighten up the containers which provide both beauty and food to this small scale urban farmer.

Edible blue flowers

Edible blue flowers

Flowerbed in the balcony

Flowers brighten up the balcony

Recently, though, she has had a personal realization of how much her little urban garden depends upon a larger network of species supported by the ecosystem of Stockholm, what we call ecosystem services in the jargon. Earlier today, she posted the following observation/lament on the apparent loss of an ecosystem service crucial to that supply of tomatoes which we enjoyed so heartily last summer.

My gracious hostess

My gracious hostess

On food, pollinators and what makes me scared:

A discovery and sudden realization yesterday made me terrified. My tomato plants, cocktail type according to the package, beef type according to the size the plants have actually grown to, have not only grown remarkably well since March but also been covered in pretty little yellow flowers for weeks. Now the flowers are falling off, and… nothing. Where little round tomatoes in abundance should now be emerging, weighing down the strong branches of the giant little plant, nothing appears.

Although the theoretical knowledge has been with me for years, it is the real experience, seeing with my own eyes, that truly makes me realize how fragile one of the most basic and vital of ecosystem functions is: pollination. Without honeybees, bumblebees and butterflies, which have been few and far between on my little balcony garden, my tiny scale food production system has crashed in the span of one single season. Suddenly I can start to imagine the potential effects of the global honeybee population decline, although it would be impossible to imagine the full effects if the pollinator system crashed – and I’m quite happy that it is.

As I am writing this, I glance at the gladiator of cocktail tomato plants next to me that with leisure nod along with the wind. One of the branches catches my eye: at its very end, well hidden beneath a labyrinth of leaves, three tiny pea-sized green tomatoes are emerging. There is hope.

Floral closeup

An urban floral closeup

Bee-assisted wind pollination? Or daylight pollen-robbery by sweat bees?

Grasses are all supposed to be wind-pollinated, right?! So what’s this sideoats grama doing flashing its bright red anthers so flagrantly? Watching the sweat bees carefully at work collecting pollen from these grass flowers, in this languid hi-def video (check out the 720p version in full screen!), you can also see puffs of pollen being launched into the still air by the bees! So are the bees providing an assist to the flowers in their normal wind-driven sex, even as they steal pollen? Do the flowers actively attract the bees or are they mere victims of pollen robbery? But if the bees are helping, and the flowers want to attract them, what are they doing with bright RED genitalia?! Those are among the questions that come to my mind, and those of several commenters over at the Myrmecos blog of Alex Wild, the biologist behind the smooth hi-def camerawork in this video. You should also check out some of his other HD videos of insects in action.

What blows me away further is knowing that this wonderful cinematography comes through a proper macro lens on a digital SLR camera! Alex has one of the new Canon 7D model that can do HD video – and this clip now has me wishing for one to enhance my own amateur photography! Now how do I justify it on my next grant?! 🙂