Tag Archives: redwoods

Summer Fog & Winter Rain

Morning fog captured by redwood trees

I’m not sure how the subject changed from heirloom tomatoes to the the number of gallons of water that a redwood tree uses daily but over lunch the other day with my friend, Colly, the food writer for the Press Banner, and Susan, another friend of ours, this discussion got me thinking about the weather. Is it too early for winter precipitation predictions when the snow has barely melted in the Sierra?

Weather shapes our lives. We celebrate when the weather is good although that might mean mild and sunny for the soccer game or a rainy day when we desperately need it. We watch the Weather Channel forecast and the satellite image for what’s headed our way. Our climate is changing but it’s the seasonal weather that gets out attention.

There have been several heat waves this summer. Recently the temps soared to the high 90’s and low 100’s in some places and remained high even at night. The next couple of days brought fog so thick it dripped from the trees. We know that redwoods thrive along the coast because of the fog. Have you ever wondered how much water a tree can get from this source?

Fog drip is precipitation that forms when fog droplets condense on the needles or leaves of trees. Redwoods especially are extremely efficient producers of fog drip but other conifers like Douglas fir and pines can collect quite a bit as do large madrone leaves. According to Dr. Todd Dawson, author of “Redwood” by the National Park Service, “A relatively small 100 foot tall redwood can gather the equivalent of four inches of rain in a single evening.”

Dawson’s studies have found that Doug firs along our coast produce anywhere from 7-27 inches of fog drip each year. He measured the fog drip below a single tanoak at a whopping 59 inches of precipitation along the Northern California coast. This summer moisture can provide as much as half the water coming into a forest for over a year. Trees can absorb a small amount of water through their needles and leaves, too. A redwood tree needs about 150 gallons of water each day. Every little bit helps in our summer dry climate.

Understory native plants in a redwood fairy ring.

Because of the water that accumulates below the trees many plants like our native Western Sword fern, the small Epipactis orchid and Phantom orchid are found in these unique conditions.

Fog drip occurs every summer. Ask Mark Twain who said “The coldest winter I ever saw was the summer I spent in San Francisco”.

But what about this upcoming winter’s rainfall forecast? What’s the latest on our chances of El Nino coming to visit and bringing more nice soaking rainfall with it?

According to the National Weather Service at NOAA, “ All in all, El Nino is still present, but just barely”. Winter is still a long way off and there are many possible outcomes from the current conditions. Hopefully, we’ll be on the winning side of these forecasts. Water conservation will always be a part of our lives. Start planning now the changes you want to make in your garden this fall.

Arbor Day in California

California’s Arbor Day is celebrated on March 7th, in honor of famed horticulturist Luther Burbank’s birthday. The day is celebrated on different dates around the world because one of the features of Arbor Day is the planting of trees which is best done at certain times of the year. The simple goal of this day is to inspire people to plant, nurture and celebrate trees.

Second growth redwood fairy ring.

We are fortunate to live here in the Santa Cruz mountains in a temperate rain forest with lots of trees. Our redwoods are especially important in our biodiverse watershed as is all flora and fauna in the forest. Redwoods and many native trees keep our environment moist. Let’s make it a priority to protect them and pass the baton of stewardship to our children who will inherit this place.

So whether you’ve been thinking about planting a redwood, heritage oak or other native tree, a fruit tree to feed the family, a shade tree to save on summer cooling, a flowering tree to attract pollinators, or a tree to hang the hammock on this is a good time to plant as well as nurture and celebrate all trees..

Trees are remarkable in how they grow and adapt to their environment. Some trees, like redwood, ponderosa pine, sycamore and madrone have especially beautiful bark. This is the tree’s protection from the outside world. Continually renewed from within, it helps keep out moisture in rain and prevents the tree from losing moisture when the air is dry. Bark insulates against cold and heat and wards off insect enemies.

The inner bark, or phloem, is the pipeline through which food is passed to the rest of the tree, It lives for only a short time, then dies and turns to cork to become part of the protective outer bark.

The next layer in is the cambium cell layer which is the growing part of the trunk. It annually produces new bark and new wood in response to hormones that pass down through the phloem with food from the leaves. These hormones are called auxins and stimulate growth in the cells. They are produced by leaf buds at the ends of branches as they start growing in spring.

Inside the cambium layer is the sapwood or xylem which moves water from the roots to the leaves. Sapwood is new wood. As newer rings of sapwood are laid down, inner rings lose their vitality and turn to heartwood.

Finally, the central supporting pillar of the tree is called heartwood. Although dead, it will not decay or lose strength while the outer layers are intact. A composite of hollow, needle-like cellulose fibers bound together by a chemical glue called lignin, it is in many ways as strong as steel.

fog filtering through the redwood trees.

Leaves make food for the tree. Their shapes help them reduce wind resistance, shed rain that could decay the leaf if left standing and produce chlorophyll. The narrow needles of a Douglas fir, for instance, exposes as much as three acres of surface to the sun.

Be kind to all trees. They are a valuable asset to your home and our environment. Earth Day is next month on April 22nd. Let’s continue to celebrate the natural beauty of our planet and learn what we can do to keep it healthy.