Category Archives: Climate change

Climate change

Flowers Adapt to Climate Change

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

I read about a study in France a while ago 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.

bees, California Native Plants, Climate change

Helping Bees Help Us

Honey bee gathering pollen

Outside the birds are chirping like crazy in anticipation of this year?s nesting activities. The bees are becoming more active every day searching for nectar in the flowering trees and shrubs. Ceanothus season is coming soon and then they?ll really be busy. Last year was a banner year for my native bees and bumble bees. There were also a lot of European honey bees around. Maybe I was just lucky. What can you do to help our pollinators in these times of diminishing habitat, disease, climate change and pesticide use?

There are 1600 species of native bees in California with several hundred living in Santa Cruz county alone. They are solely responsible for pollinating many of our native plants. Being solitary they do not make a hive but make nests underground or live in wood, one female per nesting hole and she lays her eggs there. Leaving areas in your garden near flowering plants un-mulched helps her find a nesting hole. The hard working females mate, make nests, collect pollen for their young and lay eggs. Males live to mate and only pollinate inadvertently when they visit flowers for nectar to fuel their flight.

Long-horned native bee

Common native bees in our area are the yellow-faced bumble bee and the long-horned bee which has stripes a little like a yellow jacket. The hard working bumble bee is easy to identify from its bight yellow facial hair and yellow bands on their backs and abdomens. Female bumble bees? hind legs widen to form pollen baskets often filled with bright yellow, moistened pollen pellets.

The long-horned native bee gets their name from the long antennae of the males although the females do not have this. Males may be seen by day jostling for female attention above a patch of blooming plants while the females are collecting pollen. Only the females have branched hairs on their legs for carrying pollen.

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 our area 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.

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.

Honey bee searching for nectar and pollen

The higher temperatures that come with climate warming can affect a bee?s ability to detect a flower?s pollen. A flowers scent is what tells a bee that nectar is present. If the weather gets to hot the plant will spend less energy on producing fragrance and just try to survive. When flowers stop emanating these enticing smells, some bees have a tough time finding food and may abandon certain area. Studies have shown that warming climates already have affected our central coast bumblebee population during the past 30 years especially the California bumblebee.

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

Honeybees and native bees need help to survive and we’re the ones to give it. Besides planting nectar and pollen sources you can help by buying local honey which support beekeepers.

Climate change, fall foliage

Quaking Aspen, Fall Color & Climate Change

Inspired by a website called ?Dude, Autumn Happens Here, Too? (https://www.californiafallcolor.com/ ) I set off last week to see the quaking aspen groves in the Sierra. As I drove up Highway 4 and over Ebbetts Pass the aspen groves came into view. Markleeville and Monitor Pass displayed some nice color, too. As I enjoyed the fall display I wondered if they would be as beautiful for future generations or if our impact on the environment would cause these glorious trees to change in any way.

Quaking Aspen on Ebbetts Pass, Hwy 4

Quaking aspen (Populua tremuloides) is the most widespread tree species in North America. They generally grow in high altitude areas but also exist at sea level in places like the state of Washington along the Pacific coast where climate conditions are ideal. Quaking aspen provide food for foraging animals and habitat for wildlife. They also act as a fuel break retaining much more water in the environment than do most conifer species.

High mountain systems, such as the Sierra Nevada, are uniquely sensitive to anticipated global climate changes and act as “canaries in the coal mine” to provide early signals of significant climate-driven changes. Research in the Sierra Nevada by Pacific Southwest Research Station, a USDA Forest Service research organization, shows how vegetation has responded to climate in the past and indicates changes than might be coming in the future over the next decade.

Climate has a profound influence in shaping our environment and natural resources. By looking at tree ring records of living and ancient wood and pollen lake sediments present climate can be compared to historic patterns to show climate changes.

Research indicates a complex, unpredictable future for aspen in the West, where increased drought, ozone and insect outbreaks will compete with carbon dioxide fertilization and warmer soils with unknown cumulative effects. They are vulnerable in the face of climate change. Hopefully, we will not lose this wonderful tree in California.

Weather conditions play a major part in the intensity of fall color. The time of year is nearly consistent but some years the show is more dramatic than others. The best conditions for intense leaf color to develop are dry sunny days followed by cool, but not freezing nights.

Which plants put on the best show in our area? Here are some of my favorites.

California native Western redbud turns yellow or red in the fall if conditions allow. This plant is truly a four-season plant starting in spring with magenta flowers, then leafing out with apple green heart shaped leaves. Colorful seed pods give way to fall color. This small native tree or large shrub does well as a patio tree in gardens with good drainage.

Other native plants like spicebush and Western azalea turn yellow or gold in the fall. A native vine that lights up with the onset of autumn is Rogers Red California grape. If you have an arbor, wall or fence that needs covering quickly this is your plant. The green and gray leaves are transformed in autumn into great draperies of rich, scarlet leaves with clusters of summer fruit turning all shades of purple.

Edibles that turn color in the fall include blueberries, pomegranate and persimmons.

Trees and shrubs that do well in our area and provide fall color include Chinese flame tree, ginkgo, Idaho locust, Chinese pistache, crape myrtle, witch hazel, all maples, liquidambar, katsura, dogwood, locust, cherry, crabapple, oakleaf hydrangea, barberry and smoke tree.