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.

Design trends

Your Garden and Bees

Yarrow (achillea) strongly attract bees with their nectar and pollen.

You can hear them a long way before you see them. I’m talking about the hundreds of honey bees feasting on the highly nutritious pollen of the Crape Myrtle blossoms. I confess I don’t know a lot about keeping bees. I even had to look up what a nuc was when offered as a pre-order from Mountain Feed in Ben Lomond. BTW- a nuc is a small, fully functioning hive. It consists of 5 deep frames containing all stages of brood and live adult bees along with a young well-bred queen. However, I do know how to attract all types of bees to the garden and here are some tips and interesting information about the bees in our area.

There are 1600 species of native bees in Santa Cruz county. 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.

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 and provide pollen in your landscape and vegetable garden are herbs such as African blue basil, bee balm, 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, achillea, aster, coreopsis, sunflowers, monarda, aster, butterfly bush, sweet alyssum, alstroemeria, red hot poker, gloriosa daisy, verbena, scabiosa, coneflower and echium also attract bees of all types.

The higher temperatures that come with climate change 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 too 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. Use only organic pesticides and avoid applying during mid-day hours when honey bees and pollinators are most likely to be out foraging for nectar and pollen on flowering plants and only then if you can’t control a pest with any other methods including Pest Management techniques. Help save the bees.

Design trends

Finding Our Horticultural Heritage

Planted in the early 1900’s by settlers, canna lilies are easy to care for.

I used to live in Bonny Doon where a huge Tasmanian Tree Fern grew without care on the “lower forty”. It was over 50 years old at the time of the fire having been planted by the original builder of the house. I guess it qualified as a heritage plant. There is so much horticultural history in our area. I’m fascinated by it all.

This area is rich in history. I love to look at old photos and try to identify what the early settlers planted around their homes in the Santa Cruz mountains.

I’ve spent hours reading through the history of the Alba Schoolhouse online. Besides the history of the actual schoolhouse, which dates back to 1895, there are many first person accounts of who grew what crops and how the land along Alba Road was used and is part of our local horticultural history.

Did you know that vineyards stretched along the west side of Empire Grade opposite the eventual route of Alba Road? In 1884, as many as 2000 gallons of wine was produced? The Burns family also had cattle on their ranch. A 1915 photo of their house show palms and hollyhocks, too. Ben Lomond became known for fruit other than grapes. Orchards of prize winning apples, peaches and plums were planted as well as strawberry plants. These crops thrived in the sunshine created by the clear cutting of timber.

Out on Bear Creek Road, the Ercoli villa featured yucca which I saw in many early photographs. Most likely they originated from the deserts in the southern California and Mexico and were brought north by the missionaries.

California fan palms and canna lilies appear in many early landscapes. The Middleton house in Boulder Creek was heavily planted with native western sword ferns. Black locust trees planted for their fragrance and flowers are still seen here today where they have naturalized. Originally planted for erosion control, particularly on strip mined areas, their durable timber was used for homes.

Many settlers arrived from the east coast, the midwest and Europe and brought with them seeds and starts of plants. As early as 1871, nurseries in San Francisco were importing plants such as pittosporum tenuifolium and the 1915 Panama Pacific Exposition in San Francisco allowed many more plants to become available to homeowners. Hebe from New Zealand was all the rage. The brochure for this World Fair describes a Palace of Horticulture and Tower of Jewels as …” a great garden, itself, a marvel of landscape engineering skill… one side of a magic carpet on which these beautiful palaces are set with its floricultural splendors for a wondrous beauty, has never been equaled.”

The 1915 Panama Pacific Expo introduced more than plants to the public. In 1916, construction of a home in Brookdale featured timber, flooring and doors shipped from the Expo to this area by Southern Pacific railroad. When the house was finished in 1926, photographs show a beautiful home surrounded by hollyhocks, roses and wisteria.

My interest in early local horticulture started after looking at a friend’s family photographs from the early 1900’s. His family had a resort with a natural spring and rock-lined forest paths close to Highway 9 in South Felton. This was very near the Big Tree Grove resort ( now Toll House ) that opened in 1867. I remember looking at the photos and marveling at all the flowers surrounding the dwelling. The redwood trees have now grown back but at that time there was lots of sunshine, a by-product of clear cutting. I could see roses, lilacs and Shasta daisies in the photo surrounding a wrap around porch.

Beginning in the 1930’s, peat moss was removed from Scotts Valley and taken to San Francisco to supply soil and fertilizer for difficult indoor plants such as gardenias. The land from Burger King on Scotts Valley Drive over to Safeway on Mt Hermon Road was a peat bog. When the peat ran out, sand and gravel were quarried and sold. There were apple and cherry orchards at the north end of town and vineyards on both sides of Highway 17. The subdivision, The Vineyard, was named to memorialize the past land use.

You can tell a lot about landscape plants from old photographs. It’s a fun trip down memory lane and part of our horticultural heritage. You might even plant a historical garden for the fun of it.

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