East Bay Regional Park District

Here in the East Bay of the San Francisco Bay Area, we have access to thousands of acres of undeveloped land, which is under the stewardship of the East Bay Regional Park District. The Park District provides oversight for multiple parks throughout Alameda and Contra Costa counties. The parks preserve open land and watersheds in a growing urban area, for our enjoyment now, and for future generations.

Most of the plant communities associated with regional microclimates are represented in their holdings, including oak woodland, chaparral, coastal scrub, grassland, redwood forest, mixed evergreen forest, coastal dune, coastal strand, riparian, and so forth. This commitment to preserving some pristine land is a treasure for anyone interested in native plants, hiking, or getting back to nature.

East Bay Regional Park District provides stewardship
for many parks and open spaces

I have enjoyed hikes and events with family and friends in Briones, Temescal, Tilden, Leona Canyon, Redwood, Huckleberry, Roberts, Sibley, and Crown Beach, to name a few. I’ve also helped remove invasive plant species in several parks. To learn more about the East Bay Regional Park District: http://www.ebparks.org; about individual parks: http://www.ebparks.org/parks; and for plant checklists: https://www.ebparks.org/natural-resources/biodiversity/plants-checklist  (select by district, or specific park).

Plant Identification Resource

One of my favorite resources is the book Plants and Landscapes for Summer-Dry Climates of the San Francisco Bay Area. It is published by the East Bay Municipal District (known as EBMUD by locals). The book is filled with beautiful, glossy photographs, information, and illustrations.

A great resource for identifying plants
in the San Francisco Bay Area

A main feature is the Plant Catalog, which includes about 200 pages of plant photographs. The information is sorted alphabetically by the scientific plant name [the binomial name, which includes the family and genus, such as Eschscholzia californica (California poppy)]. The plants are not all natives, but those that do well in the Mediterranean climate and are not invasive.

I have spent many happy hours reviewing its glossy pictures to identify a tree, shrub, or flower I’ve seen. But the book is more than pictures; it includes great information about local climates, plant communities, garden designs for the summer-dry garden, and plant lists sorted by type.


Native Plants of Leona Canyon

I know more about Mediterranean and desert plants than I know about the local plants in the San Francisco East Bay. I plan to change that, and hope the change works its way into my shady, woodland, Oakland Hills garden.

A great local resource is the East Bay Regional Park’s network of parks and open space preserves. These parks enable you to see plants in their natural regional environments, such as oak woodland, chaparral, coastal scrub, grassland, and redwood and mixed evergreen forests. I learned to identify a few of the local plants at the Leona Canyon Preserve in the Oakland Hills.

Lupine	Sticky Monkey Flower
California Blackberry	Coastal Sage Brush

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Preserves located close to population centers frequently include non-native plants introduced intentionally, or naturally from their proximity to personal gardens. This makes it tricky for the newbie to distinguish between native and non-native plants. The East Bay Regional Park District runs an ongoing volunteer program to remove invasive, non-native species from the parks and preserves.

Invasive French Broom provides beautiful
color, but forces out native plants.

The Teacher’s Trail Guide publication for Leona Canyon includes a great write-up of native plants: http://www.ebparks.org/parks/leona. The park-specific write-up for Leona Canyon also provides information about its native species. For more plant lists see the Wild Plant Checklists.

Special thanks to Quackit for use of the HTML table generator: Quackit Webmaster Tutorials

Leona Canyon Preserve

May is a great time to hike in the Leona Canyon preserve, which is located in the Oakland Hills. The canyon and hills are green from winter rains, and the wildflowers are blooming. The preserve is part of the East Bay Regional Park District’s network of parks and open space preserves. We took a short hike starting from the Merritt College trail head, but didn’t make it all the way down the canyon.

Lush vegetation on the Leona Canyon trail, near
the Merritt College trail head.

An interesting aspect of the trail is that to the East, the hillside resembles chaparral, and to the West, woodlands. This is typical of the San Francisco East Bay, where sunny facing slopes are dry with sparse vegetation, and shaded slopes, which are shrouded in coastal fog for longer periods, support lush vegetation.

Taking a breather to enjoy the canyon view. You can see
the difference in vegetation between the hill on
the left and the one on the right.

I am interested in seeing native plants in their environment, to learn more about what grows naturally in the area, and to consider what might be adapted to my shady garden. The brochure at the trail head is very informative about native plants, and their uses by the Ohlone people who lived in the area. The trail has corresponding markers for the information described.

To learn more about the East Bay Regional Park District: http://www.ebparks.org/. To learn more about the Leona Canyon Regional Open Space Preserve, see the Teacher’s Trail Guide publication on Leona: http://www.ebparks.org/parks/leona.

To get to the Preserve:
There are two trail heads – one from the Merritt College campus, and one from Oaks Canyon Drive off Campus Drive.

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Fighting Soil Compaction

I have done some research into how to fight soil compaction, so I can come up with a game plan for restoring my compacted soil to healthy, productive soil. The primary thing I learned is that it is difficult to restore compacted soil, and the best solution is prevention. Great. But there are some guidelines and principles I can use:

• Break up the ground to start the process of adding pore space.
• Don’t work with wet compacted clay soil. The molecules can slip into even more compacted configurations. Let the soil dry out a bit.
• Add organic matter, such as compost, to the soil. Work the organic matter into the top few inches of soil. Organic matter breaks down quickly, so this is an iterative process of adding organic matter, working it in to the soil, letting it break down.
• Use mulch to cover soil if you do not plan to plant immediately.
• Keep people from walking over the soil, to prevent further compaction. Ideally provide paths where needed.
• Use a cover crop to protect the soil, and even develop it. In agriculture, farmers plant a cover crop, such as alfalfa, between other crops. A crop like alfalfa, a legume from the Fabaceae (formerly Leguminosae) family, can actually grow in poor soil, and fix nitrogen in the soil to enrich it. Cut the foliage at the end of the growing season, but leave the roots in the soil to improve aeration.

Agriculture uses cover crops to hold the soil in place,
 and enrich the soil. The same principle can work
in the personal garden.

I learned a lot about soil from the Soil Management class I took from Dr. Ed Brennan, and from a soil compaction project I worked on with team members in the Arboriculture class I took from Jocelyn Cohen, both at Merritt College. Stay tuned to see if this research and knowledge pays off!

Soil Compaction

Healthy soil is a blend of decomposed minerals, organic material, microorganisms, and pore space, which provides oxygen. Soil characteristics include color, structure, and texture. Soil color is influenced by the parent mineral, for example, a red soil may indicate iron. Soil structure describes how the soil arranges itself in aggregates, for example, clay soil dries in hard, dry clumps. Soil texture is the composition of sand, silt, and clay, for example, sandy soil drains quickly, where clay soil holds on to water. Healthy soil should be teaming with life to provide a home for trees, shrubs, and plants.

Soil can become compacted, which means pore space is reduced or eliminated. This may happen purposefully during construction of a house, where soil is compacted to stabilize the soil. This can also happen when raindrops strike bare ground over a period of time, ground is used as a path or road, or ground is left fallow with nothing growing in it. When soil becomes compacted, water runs off and does not penetrate the soil; roots cannot move through the soil as easily; and the water and oxygen exchange between soil and roots cannot take place. The microorganisms that are required for healthy soil cannot live in this condition. The soil becomes unusable.

Soil has become compacted in a section of the yard
where a tree was removed.

My garden has an area where the soil has become compacted. We took out a pine tree several years ago that had grown out of scale for the property, and was growing close enough to the house to become a fire hazard. We cleared out the tree roots, but never replanted anything in the area. The soil has become compacted, with nothing growing on it except for a colony of moss which revives during the winter rains. The rest of the year, the soil is like a clay brick. I’d like to restore this patch of ground to life.

Working With an Arborist

Arborists specialize in arboriculture–the care of trees, shrubs and woody plant material outside of a forest setting. They may work in a municipal or utility setting, keeping public trees healthy and safe, or utility right-of-ways cleared. They may work in a commercial setting, caring for private trees, removing dead or problematic trees, or providing consultation services. Certified arborists are well trained in the health and care of trees, and versed in the municipal requirements for urban trees.

The International Society of Arboriculture (ISA, http://www.isa-arbor.com/) is a great resource for finding a certified arborist, learning more about arboriculture, and finding out about certification. Becoming a certified arborist requires several years of field experience, rigorous testing, and ongoing education. The ISA provides certification in these key areas:

· ISA Certified Arborist

· Arborist/Utility Specialist

· Arborist/Municipal Specialist

· Tree Worker/Climber Specialist

· Tree Worker/Aerial Lift Specialist

· Master Arborist

An arborist is a wonderful asset for your urban garden. I’ve used Brende and Lamb in the San Francisco Bay Area for years, to prune and care for our big oak and elm trees. If we had contacted them at the first sign of trouble, we might have been able to save the maples.

Street trees in Dublin, California

Arborist to the Rescue

It's the retaining wall

Our arborist came to assess the health of our trees, and give an estimate for pruning some of the big trees. This is something we do every two or three years to keep the trees in scale with the property, and ensure safety.

He also gave a diagnosis for the death of the three maple trees - last year’s broken sprinkler and the retaining wall conspired to flood the roots and drown the trees. Roots need oxygen in the soil in order for the tree's hydraulics to work. The water and oxygen exchange draw water up the trunk and out through the leaves. With flooded roots, the tree suffocates.

The soil may have also become compacted. Soil compaction can be a problem with clay soil. The solution to this is aeration to increase pore space in the soil, enabling a better exchange of water and oxygen. The process involves using an aerator to dig holes in the ground every 18 inches, and fill the holes with compost.

Once we remove the trees , we'll be  planting new maple trees, because we miss their beauty, elegance, and grace. 

Evil Comes to Eden

Death has come to my little piece of Eden - three Japanese maple have died. All three maples stand in a row, near a retaining wall, which separates the slope of the yard from the patio. All three maples have thrived since we moved into our home fourteen years ago. All three maples now show the same symptoms – first the buds did not develop last spring, then mushrooms and conks began to grow in the fall, then the bark peeled on the northern face of the trunks in the winter. Looking back, death happened over a period of time, so I could have take action sooner.

One of the maple trees - notice the
peeling bark

And, looking back, I can see several events that may have contributed – several years of drought, followed by two very rainy seasons. There was as sprinkler incident last spring, where we realized we had an underground leak, which might have flooded the root zone. Perhaps the soil itself is infected with something. A beetle infestation might explain the peeling bark (although, in the Arboriculture class I took last fall, we learned that pest infestations may be a secondary symptom for a tree that is already in a weakened state).

Symptom: dead branches

Symptom: peeling bark

Symptom: conk (the fruit of a wood-rotting fungus)

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Another possibility is that circling roots may have strangled the trees (I also learned in the Arboriculture class that many container grown trees develop circling roots; after they are planted, the trees grow fine until they reach a certain size, and then the roots cut off the vascular system and strangle the tree). And a final thought is that every living thing has a life span, and eventually dies. Enough speculation, it is time to call in our arborist, Brende and Lamb of Berkeley (http://www.brendelamb.com/), to diagnose the problem. They have been pruning my big trees and providing guidance for years.

Mom's Garden

My folks have lived in Southeast Alaska for over fifty years. Southeast Alaska is an arboreal rainforest that receives an average of 58 inches of rain a year, making it green and lush. Most of Alaska is a wild garden, but Southeast Alaska seems especially beautiful. The Sunset climate zone is A3 (mild, maritime climate, with influence from the interior of Alaska and Canada), and the USDA Plant Hardiness Zone is 5b-7a. The growing season is short but intense, with 12 to 18 hours of daylight during the summer.

Mom and Dad have tamed the wilderness surrounding their home, clearing the dense underbrush to create a small lawn and several raised flower beds. They frequently grow containers of beautiful flowers, many started from seed by my sister-in-law early in February. In the back yard they grow rhubarb, and harvest wild blueberries that are wonderfully flavorful from the moist, tannic soil. Gardening in Southeastern Alaska has many challenges, including the short season, drainage issues, blue clay, mold, not enough sun, and too much rain. But the rewards are well worth the effort.

Mom's garden in Southeast Alaska

Mom is a lot like her garden – gracious, beautiful, welcoming, hardy, and tenacious. She is at home in the wilds of nature (whether cold, damp forest, or hot, dry desert), and in concert halls, opera houses, and theaters (a consummate Lipstick Adventurer)! Mom is a continual source of inspiration and encouragement, and an oasis is the wilderness of life.

Japanese Gardening

I would love to know more about the Japanese gardening style. I think I “know it when I see it”, but I really don’t know all that much. When I think of a Japanese garden I think of a serene place that is very naturalistic - nature is tamed to present the best of itself. A Japanese garden is comprised of plants, and structures, such as small buildings, lanterns, paths, bridges, and ponds. Ideas may be represented in the Japanese garden, for example, water may be represented by gravel or sand, and plants may represent life.

When I think of a palate of Japanese plants, I think of iris, camellia, rhododendron, azalea, pine, and maple. I also think of a very distinctive pruning style, which showcases the trunks, branches, and leaves of each tree. The aesthetic pruning class series that I have been taking at Merritt College is heavily influenced by Japanese gardening.

Pine tree

My garden benefits from the pruning skills of Yakito who is a pruning artist in the Japanese style. His artistry has found its way to many of the trees in my garden.

Maple tree

Kimura Style Gardening

Kimio Kimura designed the Japanese Gardens of the Hayward Area Recreation and Park District over a period of 30 years, and continues to tend the garden. Kimura was born in Japan, and migrated to the United States to attend University. At the prompting of his father, Kimura studied economic and international business for his undergrad degree; Kimura switched to Landscape Architecture for his Masters Degree at University of California, Berkeley.

Kimura uses physical objects to demonstrate dynamic
groupings of rocks and plants.

On the first Saturday of the month, Kimura gives an informal lecture about his Japanese gardening ideas, which he calls Kimura style. The basic garden elements are water, stone and plants. He demonstrates how to achieve dynamic balance by grouping two or three components in different combinations – varying texture, placement, and height. He also describes the importance of each gardening element as an individual, and its contribution to the overall garden.

Here Kimura uses objects to help students
visualize the distinctive layered look
of a pruned tree.

I learned a lot from Kimio Kimura, and plan to return to learn more. It is inspiring to learn from a master, and Kimura encourages students to ask questions. He is writing a multi-volume book that describes and illustrates his design principles.

 

Hayward Japanese Garden

I recently visited the Japanese Gardens of the Hayward Area Recreation and Park District. The garden was designed by Kimio Kimura, of Kimurascaping, using the principles of traditional Japanese garden design. For an informative description of the garden and its interesting history see the Wiki page. The garden is peaceful and beautiful, a wonderful place for meditation or contemplation.

Path through the garden.

My focus was on pruning, so I was especially interested in the trees and shrubs, and the feel of the garden. I could see many of the principles I’ve been learning in the Aesthetic Pruning series taught at Merritt College, including unveiling the best of a tree or shrub, showing particular traits in bark, leaves or needles, stems, and so forth.

Beautiful trunks revealed.

Gracefully flowing needles.

The garden follows traditional garden design, but uses the plants, rocks, and materials of the local environment. This is a great model for developing a garden in the San Francisco Bay Area. You can emulate or follow a favorite gardening design, but incorporate native plants and materials that will thrive in the local environment.

Holly bush incorporated into the garden design.

This is a garden to visit again and again, for personal reflection and respite from the cares of the day, and to view the seasonal changes unfold.