permaculture@lists.ibiblio.org
Subject: permaculture
List archive
[permaculture] NYT: Native plants attract pollinators better
- From: "rafter t. sass" <rafter@liberationecology.org>
- To: "Northeastern Permaculture (List)" <northeasternpermaculture@lists.riseup.net>, permaculture@lists.ibiblio.org
- Subject: [permaculture] NYT: Native plants attract pollinators better
- Date: Fri, 1 May 2009 14:37:33 -0400
Pretty significant findings for polyculture guilding...
rafter t. sass
The Liberation Ecology Project
liberationecology.org
518-567-7407
skype: raughter
-------------------------------------------------
http://www.nytimes.com/2009/04/30/garden/30GARDEN.html
The New York Times
April 30, 2009
In the Garden
Come Hither, Bumblebee, and Pollinate
By ANNE RAVER
MY native black cherry tree is covered with little white flowers, and if the bees and other pollinators do their job, I'll have plenty of sweet black cherries by midsummer.
My Korean spicebushes (Viburnum carlesii) are also in full bloom, their clusters of pinkish-white flowers filling the air with the heady scent of cinnamon and honey. But it's striking how few bees are sipping nectar from these Asian shrubs compared with my native redbud and sassafras trees, which are literally vibrating with pollinators.
It bears out the research that Gordon Frankie, an entomologist at the University of California, Berkeley, has begun in gardens around that city, where he and his students have surveyed 1,000 different plants, both native and nonnative.
"Only 50 were native plants, but of that 50, 80 percent were attractive to pollinators," Professor Frankie said. "In contrast, only 10 percent of the 950 nonnatives were attractive to pollinators."
My spicebushes don't seem to be among those pollinator favorites, but I would never trade them, or my Asian lilacs and peonies, for natives. So I am adding native plants wherever I can to feed the pollinators - in particular the native bees, because there are so many different species, and far fewer nonnative ones, like the European honeybee (Apis mellifera), which doesn't seem to be much in evidence around my old farm in Maryland these days.
Douglas W. Tallamy, an ecologist at the University of Delaware, and the author of "Bringing Nature Home: How Native Plants Sustain Wildlife in our Gardens" (Timber Press, 2007), inspired my new plantings. "We have 4,000 species of native bees in North America," Mr. Tallamy said. "If we gave them food - flowering native plants - and a place to build their nests, they would be able to take up the slack from decreasing honeybee populations."
While some native bees are particular about the plants they like, about half are generalists, scientists say, which explains why I see native bumblebees and mason bees on my pear tree, an Asian plant. And why my unmown yard is abuzz with pollinators, from tiny wasps and flies to solitary native bees, nuzzling the dandelions (transglobal weeds), violets (found throughout the temperate world) and clover (largely European).
So don't be too quick to mow. Those so-called weeds are important sources of food for pollinators, which need protein and sugar to build up their populations. We need to keep feeding them from early spring to hard frost if we want vigorous, well-pollinated plants.
Crops like tomatoes, peas and beans are self-pollinating, but they still have to be shaken by the wind or bees to release the pollen inside the flowers. Bumblebees and a few other native bees are able to vibrate the flower - something a European honeybee cannot do - shaking pollen from the stamens to the stigma, where it fertilizes the ovules that will become seeds inside a pod (think snap peas or green beans!) or fruit (juicy tomatoes! strawberries!). These bees also travel from flower to flower, cross-pollinating, which improves the vigor of plants and the size of that tomato.
Other crops like the cucurbits - melons, cucumbers and squash - are entirely dependent on pollinators for fertilization, because they have separate male and female flowers.
Both honeybees and natives do an excellent job of pollinating such plants when they are around, but all these pollinators are in serious decline from many stressors, and scientists suspect that habitat loss is key.
David Salman, the founder and chief horticulturist at High Country Gardens, a mail-order nursery in Santa Fe, N.M., said he has noticed a big decrease in pollinators as the fields of wildflowers around his greenhouses have been developed.
"I'm not getting the seed production I used to, because I'm physically cut off from pollinators," he said. "I am excited beyond words about this resurgence in home food production, but the big thing left out of the equation is bringing pollinators into these gardens, particularly in urban areas."
In the kitchen garden, where many plants are a mix of European, Asian and American species, I don't worry so much about whether an herb or flower that attracts pollinators is native or not. I just go for diversity, and it all seems to work out.
So I'm not going to give up my Mediterranean lavender, catmint, oregano or any of the other age-old plants imported to the New World. I'm just packing in more natives.
In a wide border around the kitchen garden, I've planted Purple Smoke, a native baptisia or indigo, with charcoal stems and violet- blue flowers the same shape as those of the sugar-snap and snow peas climbing a nearby fence. And I've put in two indigo plants, rather than one, to get a good six-foot-wide clump, because according to my "Pollinator Conservation Handbook" (Xerces Society/The Bee Works, 2003), native pollinators are more likely to home in on flowers when they're in masses at least four feet across.
I've put in more native coneflowers, too: Echinacea purpurea, the purple coneflower, and E. paradoxa, the yellow coneflower, as well as black-eyed Susans (Rudbeckia hirta) and Rudbeckia maxima, the so- called cabbage-leaf coneflower, a six-foot plant with big blue-green leaves and bright yellow flowers.
"I love the purple coneflowers and rudbeckias, the ratibidas, or prairie coneflowers, which are all wonderful for bumblebees," Mr. Salman said. "If you have melons and squash, plant these right in the patch."
Other native perennials that provide plenty of nectar and pollen include giant hyssop, coreopsis, larkspur, Joe-pye weed, blanket flower, sunflower, lupine, evening primrose, poppy, penstemon, salvia and sedum. Annual and biennial flowers like milkweed, spider flower, cosmos, poppy, mullein, daisy and verbena also draw pollinators. So do wild roses and blueberry bushes, raspberry and blackberry brambles, elderberry and sumac, and nonnative herbs like lavender, mint, basil, marjoram, rosemary, borage and lantana.
And don't forget late-summer favorites like goldenrod and asters.
Ecologists are encouraging home gardeners to experiment with all these plants, and to observe what pollinates what. It's as fascinating as bird-watching.
- [permaculture] NYT: Native plants attract pollinators better, rafter t. sass, 05/01/2009
Archive powered by MHonArc 2.6.24.