Tag Archives: pollinators

Flowers Adapt to a Changing Climate

These cultivated violas look similar to the field pansy in the study.

On this rainy day I’m picturing my garden and deck this summer filled with colorful flowers. The bumblebees will be happy, the hummingbirds will be happy, I’ll be happy. Or will I?

I recently read about a study in France that suggests that humans are quickly altering the way flowers are reproducing and it’s happening in just 20 generations. Toxic pesticides and vanishing habitats have driven down the populations of bees and other pollinators so some flowers have evolved to fertilize their own seeds more often than the seeds of other plants.

Bumblebee populations have declined and it may be that the field pansy flowers in the study are investing their energy into using their own pollen to fertilize their own seeds more, rather than produce big flowers that lure pollinators.

The researcher in the study, Dr. Cheptou an evolutionary ecologist at the University of Montpellier, was inspired to carry out the study when it became clear that bees and other pollinators were in drastic decline. How would flowers adapt? Would they find another way to reproduce?

The field pansies have always been able to reproduce using both methods. But a selfing flower can use only its own genes to produce new seeds. Sexual reproduction allows flowers to mix their DNA, creating new combinations that make them better prepared for diseases, drought and other challenges that future generations may face.

Tracking the evolution of the field pansy was made possible by the cache of seeds from the National Botanical Conservatory in France collected in the 1990s and early 2000s.

The researchers compared these old flowers with the new ones found in the countryside. After growing the new and old seeds side by side in the lab under identical conditions, they discovered that selfing had increased 27 percent since the 1990s.

Other changes of note were that although the new field pansies had not changed in their overall size, their flowers had shrunk by 10 percent and produced 20 percent less nectar.

So this change in reproduction may be making a bad situation worse for pollinating insects. The genetic limitation of selfing could put plants at risk of extinction.

Flowering plants are dealing with other issues such as global warming which speeds up the growth of the flowers and shrinks the window of time before the flower wilts and has nectar for pollinators.

Another study, however, on morning glories in the southern United States, found that between 2003 and 2012, the flowers became bigger, not smaller. Is this a strategy to keep attracting bees as they become less common?

Being an optimist I’m hoping that nature will adapt and figure out how to keep everybody happy.

Gardens Change with Time

Whether you want them to or not all gardens change with time. It?s part of nature that the fittest survive. Possibly you have different ideas of what you want your garden to look like but it?s hard to fool Mother Nature. Several years ago I had the opportunity to visit a special garden in the Gilroy area that has evolved with time. This garden of California native plants truly demonstrates how nature can decide the best plants for birds, butterflies, wildlife and people.

It was one of those classic mild autumn days when several fellow landscape designer friends and I were treated to a tour by the enthusiastic owner of 14 acres of land. Located at the base of Mount Madonna the property is called Casa Dos Rios. Jean Myers, the owner, loves to share her property and especially the journey that has transformed it from a formal landscape with lots of lawn to the present truly native wild garden. She loves that the landscape now supports all sorts of wildlife including birds, mammals, reptiles, amphibians, insects and fish.

A few of the native plantings have been more successful than she would have liked. Jean laughed as she pointed out the California rose thicket that has taken over the entry garden. She wishes she had planted the native wood rose instead which doesn?t spread as much. Her new plan is to remove the wild rose to make room for other native plants that aren?t so aggressive.

At this time of year a native garden is at rest. There was a quietness to the landscape as the wind blew the grasses. Deer grass has naturalized in garage swaths. Originally, Jean planted many varieties of native grasses and some still remain but the deer grass have been particularly successful. Jean explained that this grass was used for making baskets by the Ohlone Indians that used to live in the area. To keep this grass fresh looking she cuts them back to 6 inches from the ground in late winter.

California aster are butterfly and pollinator magnets

The California aster was still blooming along the path as we made our way to the frog pond. This plant is well liked by the native moths and butterflies, Jean said, as it provides a late source of nectar. The lavender flowers make perfect landing pads. The two species of butterfly weed bloomed earlier in the season and had already spread their seed for next year.

The frog pond consists of basalt columns that drip water into a deep pool filled with rocks that cools the water in the heat of the summer. Jean said the area is usually alive with birds but they were keeping their distance during our visit. Lots of time for them to bathe later when we weren?t invading their space. She said Pacific tree frogs and Western toads call the area home, too.

This ground cover is fire wise native and has high quality nectar favored by hummingbirds

Another late blooming plant, the California fuchsia, covered a slope alongside massive granite boulders. You could barely see the foliage through the hundreds of flowers of this red blooming variety. These plants spread easily and with a bit of late winter pruning look great late into the season.

Native iris tolerates sandy, clay and serpentine soils and seasonal flooding

Jean loves all her native plants. From the butterfly garden to the bog garden she had a story to tell about each area. In the spring, Jean said, the native iris steal the show. She rounded up 600 of these from nurseries all over California when the garden was first planted. Grouping each type together she says was half the fun to keep the colors pure in each stand. I was amazed to see them in areas of full sun as well as part shade locations.

We picked late blackberries and raspberries as we walked around this amazing 14 acre property that benefits all wildlife. She is an avid birder and she and her husband manage two creeks, the Uvas and the Little Arthur that support hundreds more bird species, including bluebirds, swallows and owls. ?There?s so much for them to eat here.? said Myers. She lets nature feed and attract all the native wildlife that visits.

It was a privilege to listen to Jean share her enthusiasm for gardening with California natives that attract wildlife and conserve water. I left with my pockets filled with seeds from native wild grape and clematis so I was hoping to always have a bit of Casa Dos Rios in my own garden.

Bees- Pollinators for a Bountiful Harvest

Pollination or the transfer of pollen in and between flowers of the same species leads to fertilization and successful seed and fruit production in plants. Pollen can be carried from flower to flower by pollinating animals such as birds, bees, bats, moths, beetles or by the wind but bees pollinate approximately 1000 plants worldwide including apples, blueberries, chocolate, coffee, melons, peaches, potatoes, pumpkins, vanilla, almonds and tequila. Clearly we need our bees- both native bees and honeybees.

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honey bee pollinating African blue basil- photo courtesy of Gaylon Morris

Honeybees aren?t native to the United States. The colonist brought them here in the 1600?s to pollinate apple trees and for their honey and wax for candles. They are loyal to the plants they feed on and that makes them valuable to farmers and orchard owners. It works this way. When a worker bee leaves a hive in search of food it will feed on on one type of flower- whichever type it tasted first on that trip. Unlike other insects that might go from a cucumber blossom to dandelion to squash flower the honeybee sticks to one thing. That way it picks up and deposits only one type of pollen making honeybees particularly efficient in pollinating crops.

We know that honeybees are having a hard time of it due to diseases, parasites and pesticides. Planting flowers that bees like can increase the chances of bees? survival as will cultivating native plants, especially those that provide nectar and larval food for pollinators.

Bees eat two things: nectar which is loaded with sugar and is their main source of energy and pollen which provides proteins and fats. Some of the common native plants that are recommended for the ecological region of our California Coastal Chaparral, Forest and Shrub Province by the North American Pollinator Protection Campaign to attract bees of all types include yarrow, columbine, California poppy, coral bells, silver lupine, penstemon, ceanothus, toyon, big leaf maple, mahonia, monkey flower, buckwheat, western azalea and purple sage.

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honey bee on echium wildpretii

Common garden plants that can attract bees to your landscape and vegetable garden are herbs such as African blue basil, oregano, mint, catnip and cat mint, borage, rosemary, chives, hyssop, dill, comfrey and fennel. Edibles that attract bees are blueberry, pumpkin, squash, sunflower, blackberry, hazelnut, artichoke, beans, cucumber and peas. Crabapple, iris, lavender, salvia, sunflowers, monarda, aster, butterfly bush, sweet alyssum, alstroemeria, red hot poker, gloriosa daisy, scabiosa, coneflower and echium also attract bees of all types.

In your own garden an abundant and healthy population of pollinators can improve fruit set, quality and size. Crops raised in California depends on both domestic honeybees and native bees for pollination of almond, blackberry, cucumber and artichoke crops.

We can all help honeybees and other pollinating animals by being more mindful of the way we tend our yards. Reduce the amount of lawn you have and plant natives and flowers that will attract them. Use organic pesticides carefully and only if absolutely necessary. Buy local honey and support beekeepers. Honeybees and other pollinators need help to survive and we?re the ones to provide it.