Tag Archives: climate change

Fun Facts about Fall Color

Eastern Dogwood showing off fall foliage

The weather has been perfect for us to have great fall color this year. Because it’s been warm during the day and chilly at night I’m looking forward to the show. Many trees and shrubs are already showing color because they are stressed from lack of water. Others will wait their turn and baring a wind storm which would dry out leaves before their time we’re in for a beautiful fall.

The vivid colors in a leaf are always there. They are just masked by the green chlorophyll which is busy making food by photosynthesis while the sun shines.

Come autumn, shorter days and cooler temperatures cause the trees to switch to energy-storage mode and their leaves stop producing chlorophyll. The leaves actually develop a corky later of cells between the leaf stalk and the woody part of the tree. This slows the transport of water and carbohydrates. The manufacture of chlorophyll is slowed and the green color of the leaves begins to fade, allowing the other pigments to show through. For the few weeks before the leaves fall to the ground, they are colored only by their natural pigments that have built up in the sap. Depending on the acidity of the sap – red and purple anthocyanins, yellow and orange carotenoids – fall foliage can be glorious, sometimes anyway.

I read that the fall color in the eastern U.S. is not quite as great this year due to their exceptionally hot and dry summer. The Rockies are rockin’ it this autumn because of the summer’s monsoon rains. And our own Eastern Sierra Quaking aspen show is in full swing.

Quaking Aspen

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 high places 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 global climate changes and act as “canaries in the coal mine” providing 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 that 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. Aspen are vulnerable in the face of climate change. Hopefully, we will not lose this wonderful tree in California.

Lagerstroemia in fall color

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 California native plants like Western dogwood, Spicebush and Western azalea turn yellow, red 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 red leaves with clusters of summer fruit turning all shades of purple.

Trees and shrubs that also provide fall color include Eastern dogwood, Chinese flame tree, Ginkgo, Idaho locust, Chinese Tallow, Chinese pistache, crape myrtle, smokebush, witch hazel, all maples, liquidambar, katsura, Eastern redbud, sumac, crabapple, goldenrain, locust. oak leaf hydrangea and barberries.

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

Light up your garden as the light fades and the days shorten. Now through late fall is a good time to shop for plants that change colors because you can see in person just what shade of crimson, orange, scarlet or gold they will be.

The Power of Nature

Although not a mangrove or salt marsh, this Ginkgo, one of the oldest living tree species in the world, does its best to absorb CO2 from the environment.

We live close to some outstanding research facilities. NASA Ames Research Center in Mountain View had a role in the development of the Webb telescope that launched earlier this year. Stanford University is on the cutting edge of many medical advancements. Lawrence Berkeley and Lawrence Livermore National Laboratories are front and center of many studies that affect our daily lives.

When I was a kid my father used to work at the Lawrence Berkeley Lab. As a welder during the 1950’s I remember him telling me about working on the Bevatron which was the state of the art particle accelerator being built there. The goal of Berkeley Lab has always been to bring science solutions to the world.

Their newsletter, now published online, reported the results several years ago of a study about the increased rate that the earth’s vegetation is absorbing human-induced CO2. Never underestimate the power of nature – especially that of plants.

A new study published in this month’s Berkeley Lab newsletter, has found that plants, especially sea grasses, mangroves and salt marshes, are grabbing more carbon from the air than in previous decades. The study is based on extensive ground and atmospheric observations, satellite measurements of vegetation and computer modeling. They are even better than forests and can continue to do so for millions of years. The carbon found in coastal soil is often thousands of years old.

“To be clear, human activity continues to emit increasing amounts of carbon”, the study explains but plants have slowed the rate of increase in the atmosphere by absorbing more. “It’s a kind of snowball effect: as the carbon levels rise in the atmosphere, photosynthesis activity flourishes and plant take in more carbon, sparking more plant growth, more photosynthesis and more carbon uptake.”

Another player was identified in the study. Plant respiration, a process in which plants use oxygen and produce CO2, did not increase as quickly as photosynthesis in recent years. This is because plant respiration is sensitive to temperature. The study showed that between 2002 and 2014, plants took in more CO2 through photosynthesis but did not “exhale’ more CO2 into the atmosphere through respiration.

What does this all mean? “This highlights the need to identify and protect ecosystems where the carbon sink is growing rapidly,” says Trevor Keenan, a research scientist and author of the paper. “Unfortunately, this increase in the carbon sink is nowhere near enough to stop climate change. We don’t know where the carbon sink is increasing the most, how long this increase will last, or what it means for the future of Earth’s climate.”

Still I’m hopeful that the earth will heal itself if given the chance and we can thank plants including the humble houseplant for helping offset increasing levels of CO2 from fossil fuel emissions.

Berkeley Lab is at the forefront of research in the world of science. They continue to share information about how plants transport water from their roots up through the stem and how they respond to stress such as drought. The new data will provide insight about how to better tend crops and other plants under stress and to improved understanding and forecasting for drought-related die-offs of trees and other plant species.

Several years ago during the Ebola outbreak, Berkeley Lab was one of the research facilities searching for a cure. Rather than using human or lab animals, a crystal isolated from the cells of a broccoli related plant called mouse-ear cress, provided the target related protein. Researchers have used this plant as a model species for studying cell activities and genetics since the mid-1940’s and in 2000 this plant’s genome was the very first plant genome to be sequenced. Quite an honor for another humble plant.

The current Department of Energy Lawrence Berkeley Lab newsletter reported that the site of the former Bevatron, that operated from 1954 to 1993, has been designated a historic site by the American Physical Society for its exemplary contributions to physics. Dad would be proud to have been a part at its inception.

The current issue of the newsletter features a study conducted along with Michigan State University and the University of Southern Bohemia (yes, that’s a real place) about microbial photosynthesis. According to the article this info could help researchers remediate harmful algal blooms and develop artificial photosynthesis systems for renewable energy among other awesome applications. Check out the Berkeley lab newsletter online if you’re into browsing the internet like me. https://newscenter.lbl.gov/

Fall Color & Climate Change

Although it?s a bit early around here to see fall colors it?s happening at the higher elevation. Or is it? Have the wildfires affected the changing of the leaves? And what about the effects of ongoing climate change? How is our planet changing?

Ebbet’s Pass

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 global climate changes and act as “canaries in the coal mine” providing 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 that 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. Aspen 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.

Recent wildfires have had an effect on changing leaf color. Not much had been studied in this field prior to the 2018 fires that ravaged our state. Researchers? measurements have shown that the total amount of sunlight available to a plant for photosynthesis decreased only slightly – about 4% – compared to the previous summer. The smoke didn?t block the light but scattered it. Direct sunlight might fall mainly on the upper foliage but diffuse light can reach greater number of leaves throughout the canopy. So smoke can have some affect on photosynthesis but not much more than a cloudy day. Oxidative stress levels can occur during expended smoke exposure, however, so for the health of your plants be sure to wash the leaves off after a smoky day.

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.

More on our own fall color later.