DryStoneGarden

Plants, Stone, California Landscapes

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Middle Harbor Training Wall Memorial

This little jetty sticking out into the mudflat (click on all of these to see them bigger) is a memorial to one half of the Bay Area’s largest and most ambitious drystone construction, the Oakland Harbor Training Walls. It’s in Oakland’s Middle Harbor Shoreline Park, which is a rather incongruous park. The park is out in the middle of the port surrounded by industrial activity, there’s a ton of lawn which no one ever uses and in fact the geese have turned rather unusable, and there are a bunch of big landscape elements that reference the history of the port: the shade structure in the photo below, a concrete path that marks the footprint of a giant 19,000 square foot building that they took down, and the rock jetty that commemorates the port’s north training wall.

The harbor’s north and south training walls were two long jetties designed to ‘train’ the tide. Unlike a typical riprap jetty made of haphazardly dumped piles of rock designed to absorb wave or tidal energy, each rock in the training wall was fitted by stoneworkers to give the wall a smooth face that would accelerate the water instead of slowing it down. Back in the 1800’s, Oakland’s harbor was shallow and it tended to fill with silt; ships could only enter it during high tide. The idea of the training walls was to channel the tide’s energy so that when the tide went out it would also suck all the silt out with it, reducing the need for dredging. The walls were started in 1874 and took twenty years to build, with some impressive stats: 310,000 tons of stone, 500,000 square feet of wall, 20 feet wide at the base, 8 feet wide at the top, 6 feet above the low water point. The north wall was 9500 feet long, the south wall 12,000. Apparently the walls worked; the signage says the port’s activity went up 2000% after they were built.

The south wall is still there, but the port the north wall out in 2001 when they widened the channel so bigger container ships could use it; as part of the approval process, they used some of the north wall’s rock to build this memorial. I didn’t do all that good with my photos of it (there’s a better one at Oakland Geology) and I might try again some time when the tide is in or I might try to find a good view of the south wall. Honestly, though, I think the appeal is more intellectual than aesthetic.

It looks a little better with some sun flare drama. You can see the contrast between the training wall’s fitted stone (above) and the riprap’s rough faces (below).

Overall, though I said it was incongruous, the park is also pretty cool. The ships and cranes and machinery right next to the park are all impressive. There’s also a habitat planting with some natives struggling against weeds and a path out to a great view of the Bay Bridge and the city. The water area of the middle harbor is being converted into a mudflat, slowly getting filled with the silt from dredging of the channel. It’s a good place to see water birds.

And the park is a great place to see the sunset. Information and a map of the park is here, a historic photo with the training walls visible on the left side is here.

Richard Serra’s Sequence

For my first bit of ‘culture’ in the new year, I checked out the Richard Serra installation at the Stanford museum. I can’t say enough how much I liked it. Richard Serra can be a bit hit or miss in my experience, but this one is great, a moebius-like double figure-eight of curved walls made out of Cor-ten steel; the steel walls form two open circular spaces surrounded by a narrow walkway. At first I thought Sequence was an odd name, but watching people walk through it, I realized that there is indeed an actual sequence to the piece, that everyone does the same thing in the same order. Everyone looks at the walls in the first open circle, then they walk through the outer figure-eight which has a disorienting feel as the walls sinuously narrow and widen, then in the second open space everyone stares up at the sky, and then when they walk back again through the outer figure-eight they tend to keep looking upwards at the sky. As you follow the sequence, you can feel it change from an object to a space around you.

There’s a slideshow with some great photos at Stanford University News and a time-lapse of the installation at Daily Serving. It’s going to be at the Stanford museum for five years before eventually moving permanently to the SFMOMA to a new wing that is under construction, but this time of year, with the sun lower in the sky so you can look up and not be blinded, is a good time to see it.

The California Native Vertical Garden

Last weekend I went to see the Drew School vertical garden by Patrick Blanc, the French botanist who started the current green wall craze. He designed a wall in San Francisco that was installed this past February . I was a little skeptical of the whole green wall thing, but then looking up at his wall — four stories high of California natives with over 100 species — my doubts evaporated. The whole thing absolutely overflows with enthusiasm for plants. Two big walls covered in natives, what’s not to love.

A pair of gardeners were doing maintenance while I was there. At first I was a little bummed to see this big orange cherry picker in front of the wall, but then I realized that it was a great opportunity to find out about the wall. I mean, I see this thing and I wonder how much does it cost, how will it age, how much maintenance does it need, and who will give me one for Christmas? Watching them work, I was impressed at how easy the maintenance actually seemed. Like any other gardeners, they cut the plants back with Felcos; they just let the green waste fall to the sidewalk and they barely even had to bend over to work. Progress was steady. It looked quite pleasant.

The plants are essentially growing hydroponically. The black flannel acts as the planting medium for the roots, and water mixed with nutrients drips down the wall, collects at the bottom and then recirculates. This is the first time anyone has ever tried something like this with California natives (he usually uses tropical plants), so the project was considered something of an experiment. Some species like Oxalis oregana or Mimulus cardinalis seem like reasonable candidates for a hydroponic wall, but some of the others like Artemisia tridentata and the Fremontodendron were a shock to me. It’s hard to tell from the photos, but up at the top there’s a Ribes sanguineum, a couple of bushy Mallows, and at least one Ceanothus.

The gardeners said they had done some replanting in September, but this was the first full maintenance pruning. They were cutting things back to do a one-year assessment of the planting and see how everything was growing. After a year of growth, some plants were starting to cover others. The Beach Strawberry was running all over the place, the Dudleyas were getting covered by other plants the same as they did in the Academy of Sciences green roof, the Lupines were short-lived, Penstemon heterophyllus looked like it was also going to be short-lived, but overall the plants were doing really well. The shrubs up top were growing exuberantly, maybe a little too exuberantly; the shade groundcovers down towards the bottom had the best year-round appearance. I found that in the places where the fabric showed between the plants, it didn’t bother me or diminish the effect.

Pretty healthy for a bunch of plants on the side of a building.

I definitely want to make it back in the spring when a lot of the plants have grown back in and are blooming. It really does have tremendous impact when you see it on the street.

Changes to the Veggie Garden

This weekend I pulled out our summer veggies and started most of our winter plants. It was a little late to be taking things out; our basil was starting to brown from the cold, the green beans were being eaten by a pest, and the zucchini was still healthy but had slowed its production. (I had planned to wait until we finished our garden shed, but that project has gotten more ambitious and is taking longer than I expected. The shed will be very cool when it’s finished, but for now it’s just at that tantalizing phase where we can see what it will be like but can’t yet use it.) After five winters at this garden, everything this winter will be plants we’ve grown before — favas, snap peas, beat greens, chard, kale, broccoli, parsley, radishes. There’s less of it this year, as our veggie garden has been slowly turning into a fruit garden, with blueberries, huckleberries, currants, and strawberries now filling up the edges

The other change from past winters is the stone edging on three of the four beds. In August, I pulled out the old scrap wood edging I built five years ago and I replaced it with scrap stone from several recent projects. Some of the stone is a little small and raggedy on the backsides of the beds, but overall I had good stuff to work with and it was fun working with four different kinds of stone in one little area. I came up one stone short with the cabernet wall and I bought the two corner stones to use with the beige sandstone, but it was a near-perfect quantity with about eight of the little bluestone squares leftover and nothing else. The saw-finished sandstone is more contemporary than I would have chosen for our garden, but I really like it.

Without the zucchini it looks a little bare and and in need of more tidying, but the stone just makes it so much better.

Barker Dam

My last post on Joshua Tree is from Barker Dam, aka Big Horn Dam. The park is a desert, but it received more rainfall a hundred years ago and homesteaders tried raising cattle there. A couple of ranchers in the area made a seasonal reservoir, first a rancher named Barker in the early 1900’s, then William Keys fifty years later. Personally, I thought it was a little weird to see this empty reservoir and rather jury-rigged dam in the middle of the desert. Keys was the kind of guy who would kill someone in a dispute and then make a stone marker to commemorate/brag about it afterwards, and some of that character (or lack thereof) shows in the design and craftsmanship of the dam. But the birds seem to like it and the visuals are interesting and it’s a stone structure on the national register of historic places, so here it is.

The reservoir was done in a couple of phases; the bottom nine feet are faced with rock and the upper six feet of concrete were added by Keys in 1950. He made a sign in a smear of concrete to commemorate/brag about this too.

The concrete had rock dumped in between the forms to save money. You can actually make a pretty nice wall this way if you place the rock a little more carefully and scrub more concrete off the faces off after you take away the forms.

Behind the dam there’s an interesting pattern of bathtub rings. Apparently the reservoir still fills to the top, flooding twenty acres during the wettest time of year.

There’s a second, lower dam below the main one, full of cattails living off the seepage.

And a cattle trough below the second dam. All in all, a funky little area.

Ryan Mountain

‘Perspective — that is the reward for hiking to the top of Ryan Mountain.’ (J. Tree signage)

In Joshua Tree there’s a peak named Ryan Mountain. I might have resisted the bait, but then at the trailhead I found a sign proclaiming that ‘The…hike up Ryan Mtn. is a reaffirmation of life. The pulse accelerates, the senses become more acute, and one may renew the acquaintance of lungs and muscles previously taken for granted.’ (Robert B. Cates, Joshua Tree National Park: A Visitor’s Guide 1995) So what’s a blogger named Ryan to do? I of course want my blog to be reaffirming. So, photos from the hike are below.

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