On the matrix (native plants, that is)

It’s spring, which is the best time for my woodland native plant garden. We live on a steep slope (50′ of elevation change over a 150′ run!) and part of it (the area on the right) gets a bit of direct sun from mid-morning into the early afternoon. The low-quality soil, destroyed by construction and decades of neglect had been planted with invasive Berberis thunbergii (Japanese barberry) bushes and Pachysandra terminalis (Japanese pachysandra) groundcover. This is our house in 2011, when we bought it. It’s a remarkably unappealing view. The house itself looks rather sad, with a terrible DIY attempt at obliterating the rare mahogany siding with solid stain and an ill-chosen salmon base above a bare red stone gravel bed.

The pachysandra largely died out during a blight and, not knowing what I was doing, I transplanted Vinca minor (Periwinkle) from elsewhere on the property to replace it. As I began to learn more about the importance of using native plants, I began planting woodland ephemerals in shady spots. Leaving the leaves and breaking up smaller sticks and twigs to decay where they fell has done a remarkable amount to revive my soil. Plants have about twice as a high a survival rate as they did just five years ago. My technique has something to do with this, but I suspect that beneficial mycorrhizae created by the decaying plant matter has a lot to do with it. In a woodland condition, scientists consider the top layer of soil to start at the ‘litter layer’ or O horizon.

In other words, don’t let contractors destroy your property by “landscraping” like you see on the left. This is really bad. It looks stupid and, with the top layer of forest soil literally stripped away, the humus-rich topsoil will dry up and blow off in the wind, exposing subsoil in a matter of years.

Over under the eaves of the house, we replaced the dead zone of rock with soil that we filled with Mertensia virginica (Virginia bluebells) and Dennstaedtia punctiluba (Hay-scented fern). The idea is that the hay-scented fern will form a dense mat in the middle of the summer. It’s not a great native plant, as it will create a thick monoculture that doesn’t perform any real ecosystem services for insects or other animals, but as we have a half-acre (0.2 hectares), there’s plenty of room for that elsewhere. The bluebells provide an early burst of interest, before the ferns come out in May and melt away by June.

I suppose it’s worth noting that we have stripped the solid stain off the mahogany façade, applied Proluxe PPG 1-2/3 (in Butternut) and painted the foundation Annapolis Gray. Also, the engineered stone landscaping has been replaced by more natural bluestone paving that I am encouraging moss to grow between (there’s nice little patch starting to the right). The layer of leaf litter only improves the soil and means there is so much less work to do than endlessly blowing out debris from the ugly rocks. Camera buffs will see that it didn’t take long for the Tamron E 35-150 to produce it’s well-known lens flare.

Back to the hillside. Again, this area gets a bit of sun and can be quite hot and dry in the middle of the summer. That said, who is to say that it isn’t the kind of exposed alpine hillside you might see on a mountaintop nearby? In response, starting in 2021, I created a matrix of native plants that has done quite well so far.

The dominant plant in bloom here is Phlox subulata (Moss Phlox), although there is some Phlox stolonifera (Creeping Phlox) in there as well, which has thrived and expanded down into the stone wall that we built in the fall of 2020. Phlox subulata tolerates full sun and hot, dry conditions well and is typically found in dry, sandy or rocky soils. A lot of gardeners, wedded to outdated ways, try to create thick monoculture carpets of this stuff. That’s not a good idea. First, it means that any spot that it doesn’t like to grown in will be unsightly. Second, it is incredibly boring. Many perennials move around, expanding in one area, dying off in another. Instead of endlessly trying to amend and replant, a more modern approach would be to use the concept of “green mulch” developed by Thomas Rainer. Here is an example from Mt. Cuba Center in April 2022:

Here the plants form a dense mat. It’s so much more interesting than the dull monoculture of pachysandra, vinca, or worse yet, mulch that people grow on their properties. And don’t get me started on grass. First, not only is this area too steep and dangerous to mow, but that is the most boring and high maintenance groundcover of all, useful only for high-traffic areas that will be used for sports, dining, or other domestic activities.

Seeking a green mulch for the hillside, I have complimented the Phlox subulata with other natives: Fragraria virginia (Wild Strawberry), Antennaria Neglecta (Field Pussytoes), Antennaria plantagnifolia, (Lady Tobacco), Quilegia canadensis, Wild Columbine, and Sedum Ternatum (Woodland Stonecrop). You can also see an Asplenium platyneuron (Ebony Spleenwort) that I’ve planted into a crevice in the rock wall. There are other plants that will grow in during the season, such as Parthenocissus quinquefolia (Virginia Creeper), a wonderful native vine that can be found for free on my property.

Fragaria virginia is a great groundcover, although there certainly can be large gaps between each plant, so it works well in this context and is happy colonizing the wall. Quilegia canadensis shoots up over the moss and seems quite happy that way. It seems that it’s goal is to colonize the wall and particularly the place at which the wall and the driveway meet.

The Antennarias are strange looking plants, from the Asteraceae family but unlike any asters I know of. They are larval food hosts for the American Painted Lady butterfly, which is fine by me. The leaves are a very light green, with white elements and the blooms, which are supposed to resemble cat toes.

There are more Mertensia virginica in the background. Note that the leaf litter compliments the plants visually, forming a background to the living matrix.

In this view, you can see the Sedum, another strange plant. It’s a succulent native to the Northeastern United States. It’s a delight to grow since once a stem breaks, it usually just roots in place. It’s not supposed to like sunny, dry slopes, but it seems to prefer this area to more shaded areas. You take your chances with plants. The only plant that I have tried planting here and have apparently failed with is Saxifraga virginiensis (Early Saxifrage and why on earth are there three separate specific epithets virginiensis, virginica, and virginiana all meaning the same thing?). Over on the left is an Allium cernuum, or Nodding onion, which will provide a spectacular display later in the year. Many of these plants—the Phlox, Sedum and Antennaria are evergreen—or at least are in part, so

One last thing, in 2021, I covered this area with arborist woodchips. This is a near-miraculous mulch and one of the few worth using. Arborist woodchips are the remnants of smaller branches, often with leaves, processed through a wood chipper. Arborist woodchips are ugly, but they are free (just ask any arborist and they will gladly drop them off) and the rapidly rotting material quickly adds mycorrhizae to the soil. Luckily, they remain unsightly for only a brief period of time, until they turn color. Maybe best to put them down in late summer when you go on vacation and before leaves fall?

The hillside matrix gives me pleasure to view daily. It’s still early in this process and it will be interesting to see what happens over the years as the area evolves.

trip report: southern Iceland

We went on a trip to Iceland last week, visiting Reykjavik and Southern Iceland. Reykjavik is remarkably small for a European capital, population 122,853 (2016 source: UN). That’s smaller than the population of the suburb of Montclair, New Jersey, in which I live, plus the adjacent suburb of Clifton, NJ. Now Clifton is twice the size of Montclair, but still. Reykjavik has a population density of 510/km^2 while Montclair’s is 2,532.8/km^2. (Wikipedia is my data source for this and most other data in this article). The downtown area is low-rise with no really tall buildings. Much of the population lives in low-density suburbs. I mention this to underscore how daft the vehemently anti-suburban discourse inherent in architectural discussion is, something I’ve been harping on since the mid-1990s.

The rest of Iceland is extremely low density due to the massive areas made uninhabitable by both past and future lava flows as well as glaciers (Iceland ranks 240th out of 248 among countries in terms of density, with only 376,248 inhabitants in a country the size of the state of Ohio, bigger than South Korea, the entire island of Ireland, just a little smaller than Lithuania plus Estonia). I was surprised that Iceland doesn’t have significant mineral wealth. The only major resource it has—besides fresh water—is geothermal power. Apparently, only 10% of the country’s geothermal energy is being converted to usable power, a number that seems quite high to me given how few geothermal plants we saw. Over 99% of the country’s energy needs are met by geothermal energy, although Iceland has only made moderate progress toward electric vehicles yet. As Tesla owners, we thought about renting one for the trip, but the number and distribution of high-speed chargers seemed a bit low. We had a BMW X1 hybrid and only saw one place to plug it in on our trip, but that was occupied so we never got to charge the battery which could only go 50km (31 miles) per charge, ludicrous for a 950km (500 mile) trip. It got a lousy 7.4 l/100km(32 mpg), significantly higher energy consumption than an electric-only vehicle. That said, according to Wikipedia, 12% of the country’s fleet is electrified, which isn’t bad, but once we got out of the immediate area of the city, these virtually disappeared. I’m sure with time, this will change. Low-cost geothermal energy had an uncomfortable side in that it requires centralized heating plants and, as usual in places that have those, like Vilnius, larger universities, and parts of New York City, heat is poorly regulated and hard to control. All but one of our seven hotels were far too hot. I am not sure why this is. It seems easy enough to regulate temperature via a thermostat controlling a valve. Even a manually-operated valve would work. Opening windows every night was frustrating and the alteration of hot and cold temperatures when a draft blew in was not what is meant by sauna culture. Conversations during a long delay at our departure gate at the airport confirmed that other people had the same experience. That said, apparently Icelanders have a saying “In Iceland, it is 25 degrees (77F) year-round… inside!” Not fun for someone not used to such warm temperatures. A strange aside: cars tend to be large and parking spots tend to be sub-compact, even in rural areas. Our 2022 rental already had major dings on both doors. Inexplicable.

Icelandic culture is certainly outsized given the small population, but the main attraction, as its inhabitants recognize, is the sublime landscape. Recall that for Edmund Burke, “Whatever is fitted in any sort to excite the ideas of pain, and danger, that is to say, whatever is in any sort terrible, or is conversant about terrible objects, or operates in a manner analogous to terror, is a source of the sublime; that is, it is productive of the strongest emotion which the mind is capable of feeling.” Although Burke was really talking about erupting volcanos and lightning strikes, in everyday aesthetic theory the sublime has generally referred to something that creates awe and feels overwhelming, as opposed to the beautiful, which is pleasing to the senses.

Kötlujökull glacier

But there is real terror in the Icelandic landscape, as anyone who spends hours driving through a lava field laid down by an active volcano will experience. We indulged in some eco-tourism by taking a “super-Jeep” up to Kötlujökull glacier so we could tour Katla Ice Cave. It was just above freezing and raining so we became extremely wet, with even my Schoeller Dryskin pants soaking through. The ice cave was impressive, but the experience of being in the starkly monochromatic landscape at the edge of the glacier was sublime: alternating bands of ice, gritty black lava sand, and volcanic ash. The scenes from Mann’s planet in Interstellar were filmed on a glacier in Iceland.

Kötlujökull glacier

The beaches of Southern Iceland are also sublime, composed of some 350 km (200 miles) of black sand coast, an unrelenting emptiness caused by the frequent, ongoing volcanic eruptions. Nothing seems to grow here. The Apollo astronauts trained in areas like this on the island and I couldn’t help but think that while I would still gladly spend some time in an orbiting hotel, watching the Earth below, these places quenched any fantastical desire I still had to go to the moon or Mars. The barrenness of these landscapes was sublime, but also a bit depressing and oppressive in a way that a forest or a meadow, in their diversity, could never be. The Icelandic terrain underscores how remarkable and precarious the evolution of life has been. Colonizing the Moon and Mars is unlikely to proceed quickly. After a period of time, the lack of flora would get to even the most committed geologist. Plants are a treasure. An hour in emptiness seems like enough.

Sólheimasandur beach
Svínafellsjökull glacier and glacial outflow pond.

Seeing the outflow pond at Svínafellsjökull glacier and the outflow lagoon at Jökulsárlón was a goal of the trip as it showed what Glacial Lake Passaic, the absent subject of my Wastelands photo essay, would have looked like 14,000 years ago. Much of North America and Europe looked like this. As it did then, so in Iceland too, plant and animal life found a way. We heard birdsong at Svínafellsjökul and there were seals bobbing up from time to time at Jökulsárlón.

Eldhraun Lava Field

Mosses and lichens cover a large part of the old lava field called Eldhraun, caused by the Skaftáreldar (The Skaftá River Fires), a cataclysmic eruption that lasted from 1783 to 1784 that had terrible consequences for the island and appears to have had a devastating effect on the entire world as well. One day the lava will stop flowing here and succession will start again. And if the volcanic eruptions are devastating, Iceland would not have risen up from between the continental plates of North America and Europe a mere 15 million years ago.

Overlook, Suðurlandsvegur

If the landscape looks like a desolate wilderness, like the fabled Fertile Crescent of Mesopotamia, Iceland has been subject to massive harm from human activity. Between 25 and 40% of the land was covered in forest when Vikings first arrived, a forest composed mainly of downy birch (Betula pubescens) that, given the harshness of the climate only grew up to about 15m in height. Other trees, like tea-leaved willow (Salix phylifolia), usually grew as shrubs. Settlement meant cutting down some 95% of the forests to create pasture for sheep and to provide wood for construction and fuel. As at the Fertile Crescent, however, soil cover was thin (see the Icelandic Forestry Service for more). Continued grazing has meant that thin soil is prone to blowing away during sandstorms. Only recently have efforts been made to plant forests again, but in the subarctic climate the process will be slow. The deforested areas of Iceland are “wet deserts” in which life is sparse. Forests are necessary to store carbon to mitigate the effects of climate change, to stabilize and build soils, and to provide a rich ecosystem. In a NYT article, Saemundur Thorvaldsson, a government forester states, “The aim now is that in the next 50 years we might go up to 5 percent covered in forest,” he said. “But at the speed we’re at now, it would take 150 years to do that.”

Elsewhere, change is much easier. In more temperate climates like most of the United States, Ireland and Great Britain (both of which have had massive deforestation… Ireland was once 80% forested and is now 11%) or Europe, it is entirely possible to bring back forests within a generation. A tulip poplar (Liriodendron tulipifera) that sprouted as a seedling on a barren hillside on my property some eight years ago is now well over twenty feet tall; the entire hillside should be covered in them by now, but previous property owners employed biophobic “landscapers” who weeded them out and put down down mulch and pachysandra instead, creating a suburban desert with no diversity. I have planted dozens of trees on my half-acre of property in suburban New Jersey. Change is possible. Glaciers and lava fields are places where we can witness the sublime, but in everyday life, let’s rewild our landscapes and find room for the beautiful again.