Coastal Flood Risk Reduction:  Planning in the face of change

Written June 18, 2013, published June 19, 2013

The National Disaster Preparedness Training Center, NDPTC, funded by the Federal Emergency Management Agency (FEMA) presented a one-day course on planning for coastal flood risk reduction at the WSU-Long Beach Research Station, June 4, 2013. Attended by a class of one dozen professionals and local citizens, the focus was on recognizing coastal flooding risks, benefits of several different types of coastal natural environments, traditional and non-traditional solutions, and the capabilities needed to increase resiliency in coastal communities. The pace was fast, the handouts copious, and the outcome positive.  For those who attended, coastal landscapes will never be seen in the same way. 

Half the population of the United States, 153 million people, is concentrated in its coastal counties. Coastal shorelines have urbanizing landscapes as populations increase. Yet coastlines are by their nature dynamic. We tend to try to ‘fix’ shorelines in a particular shape or position to suit our needs. But dynamic shorelines are going to find their own shape and placement over time, and fighting this process is getting more expensive with each passing decade.  

Flood damages (as measured in billions of dollars each year) are trending sharply upward. As a result, FEMA and NDPTC have changed their approaches to flood management from a focus on structural protection to a broader focus on damage avoidance and community resilience.  Resilience includes a diverse group of strategies, and assumes that as conditions change, solutions will readjust to reflect changing situations. 

The group delved into numerous definitions of risk, but came back repeatedly to the understanding that severe natural disasters can provide opportunities to rebuild communities, revitalize commercial districts and improve natural resilience.  After a quick review of relevant federal laws, which in some cases have precedents that date back many hundreds of years, and a discussion of “no adverse impact,” the class envisioned fully resilient coastal communities, and then moved to a detailed review of processes that impact coastal flooding. 

These processes include land-driven factors, such as rainfall and erosion, and for a local example, rain-on-snow events, which frequently result in flooding in riverside communities. Ocean factors include storms, storm surges, and tectonics. We then moved on to natural and beneficial structures, including marshes and mangroves. On low energy coastlines, barrier islands and mangroves provide very important natural energy buffers from storm surges.  On high energy shorelines, like ours, healthy outer dunes with ample sand supplies on the beach and in nearshore waters are important to maintaining natural energy buffers.  

Resilience was the key idea to which the class kept coming back. A community that adapts to change after damaging events is a community that promotes resilience. Doing things the same old way, again and again, is not adaptive in the face of change. The class formed three teams to work through a Cascadia subduction event, an earthquake/tsunami, representative of a realistic disaster scenario for this beach with resilience in mind. Out of it came three different ideas: 1. to build evacuation structures, 2.  to strengthen outer dunes, and 3. to promote a tax-base local funding solution for desired structures, whatever these might be.  

We looked at retreat plans, accommodation plans, expansion of natural and artificial coastal buffers and ways to reduce risks to coastal communities using all these tools. Land use regulations and building codes came up, along with a discussion about how proactive planning can help communities recover after a natural disaster, or completely miss out on opportunities though lack of response to changing conditions. A review of revenues and expenditures, as with other sections, took the class through several different countries. 

The class ended with a discussion of overarching ‘mega strategies’ developed by low-lying countries, such as the Netherlands and Maldives, and by coastal Alaskan communities. Along the Bering Sea, native Alaskan communities are losing their lands as permafrost melts, and are retreating to new higher locations that wrenchingly, mean a complete change of lifestyle for the residents. 

As an ecologist, this is the first time I’ve taken a class on emergency preparedness that so thoroughly incorporated long term planning into community disaster plans. The presentation is well worth a day’s time for local residents, planners, emergency preparedness staff, and community officials at all levels.  It is thoughtful, thought-provoking and represents a practical way to think about landscapes so that coastal communities have a future in the face of rising sea levels, increasingly severe storms and major tectonic events, such as Cascadia subduction zone earthquakes and tsunamis.

Surf Safety:  Rip Currents

Written June 3, 2013, photos by Kathleen Sayce and Doug Knutsen

Our beaches are visitor friendly, with wide soft sands and a gentle slope from dunes to the tide zone, but the surf zone can be deadly. The surf zone has a complex structure in summer, with layers of sand bars and channels, as many as four or five rows of sand bars. Because of the bars, there are also numerous rip currents, strong west flowing currents that run between the ends of sand bars, fed by water in the channels behind each sand bar. This structure can be seen at low tide, and is almost completely obscured at high tide. The currents are still there and flowing fast even when covered with water. 

From the air, the beach looks placid; however, a series of rip currents are active all along this summer beach. Photo by Kathleen Sayce

Where Rip Currents Form

Learn where rip currents are likely to form and what they look like:  A spot in the surf line where the break is delayed a few seconds, or where foam or brown water (with sand in it) moves seaward as waves move landward indicates a gap in sand bars; the water may also be smoother in these gaps. 

Rip currents flow seaward at one to eight feet per second, or three to five mph. They are typically 30-50 feet wide and can be more than 120 feet wide. Rips flow seaward up to 2,500 ft before completely dissipating. They can be fixed in position, or move hundreds of feet along the beach over a few hours. Beaches with several layers of sand bars tend to have the strongest rip currents––like our beach. Under optimal conditions, a rip current can form every few hundred feet along a beach, as the aerial photograph shows. 

Rip currents are hard to see at beach level, but the breaks in sand bars are not. There's a strong rip between these two sand bars. Photo by Doug Knutsen. 

Safety:  Swim parallel to the Beach

I don’t know a swimmer in the world who can swim against a rip current and win. Know what to do in a rip:  Call for help immediately. Swim parallel to the beach, across the current, until you are out of it. Then swim back to shore. 

The first line of safety is to not enter the water in the first place. If you must go in the water, find quiet back channels and pools behind sand bars. Stay away from the gaps between bars.  In the surf, don’t wade more than knee deep. Strong currents and sneaker waves are less likely to surprise you, or knock you down, in shallow water. 

Many visitors in past years who drowned on our beaches were caught in either a deep back channel behind a sand bar, or in rip currents between sand bars. They panicked, were disoriented, and fought the current. 

In or near the water, stay oriented. Never turn your back on the surf. Know where you are on the beach, and where you entered the water. The next wave could be a sneaker, a much larger wave that runs up hundreds of feet higher on the beach, and knocks down everyone in its path.  If you aren’t watching, you won’t know when it hits, and when you come up, you won’t know where you are. You can be knee deep in water one moment, and waist deep or knocked down the next.  Be very watchful of small children near the water. It’s easy for them to be knocked down by small waves. 

If jumping waves, watch the longshore flow and your position on the beach. Longshore currents can move you from the middle of a sand bar to an end in a few minutes. With the next jump, you go off the bar and into deeper water in the rip. 

Don’t swim near jetties, rocks or piers, where there are fixed rip currents. There’s a rip current off the end of the north jetty at Cape Disappointment State Park where water blasts seaward along the north side of the jetty. Fishing Rocks at Beard’s Hollow also has fixed rip currents; this is a very dangerous area to enter the water because the currents make it impossible to get ashore. Doug Knutzen, South Pacific County Technical Rescue, told me that when the surf rescue team goes in the water between Fishing Rocks and Benson Beach for a rescue, they swim out to meet a Coast Guard boat rather than try to swim ashore due to the strong rips in this area. 

If you must swim, swim with a buddy; never swim alone. Wear a float vest or wet suit to add another layer of safety in or near the water. Either one will keep you at the surface in an emergency, so you can focus on swimming instead of staying at the surface and breathing. 

The red arrows mark the location of rip currents on one stretch of beach, less than a mile, in summer. Note the complex structure, with bars and lagoons, as well as rips. The long-shore current is moving from lower right to upper left, or north to south. Aerial photo by Kathleen Sayce

The tide is always flooding or ebbing on the beach. A flood (rising or incoming) tide is especially dangerous on a sand bar. The channel you waded through to get to the bar when it was two feet deep may be five or six feet deep when you go back. Study it before you enter the water going back to shore. If a current is flowing, move to the middle of the bar and cross there, well away from stronger currents towards each end. 

Pets are vulnerable too

Pets also drown in the surf.  If you are tossing sticks in the water for your dog to retrieve, avoid likely rip current areas and back channels with strong currents. If your dog is caught in a rip current, move up or down the beach away from the current, and call your dog to swim to you. This will encourage the dog to swim out of the current. When the surf is high, keep your dog out of the water.  Dogs are naturally strong swimmers, and more buoyant than humans, but sending them into high surf and rip currents is pushing their abilities to the limit. 

For more information, check the NOAA website online at  HYPERLINK http://www.ripcurrents.noaa.gov/" http://www.ripcurrents.noaa.gov/, which has photos and diagrams about the formation of rip currents, safety tips, surf advisories, and links to other sites. 

South Pacific County Technical Rescue posts photos, video clips about rip currents, and safety tips for beach, surf and cliff safety, at  HYPERLINK "https://www.facebook.com/spctrescue" https://www.facebook.com/spctrescue. 

Doug Knutzen, SPCTR, drove the beach with me to talk about rip currents, sand bar structure, and beach safety. 

Be smart, know the signs of rip currents, and be safe, even on hot days at the beach.  

I

Building Dunes Part 1:  Where sand goes from the beach

Written April 21, 2013, published in late April, 2013, all photos by Kathleen Sayce.

Along the oceans of the world, wherever there is surf and sufficient sand, there are beaches. These are dynamic landforms; they shape and reshape themselves in the surf and wind, to grow and recede with the tides and seasons, always on the move.  Sand, waves and wind are central to beach formation. 

Sand in the surf zone and on our local beach has several potential fates. First, in the intertidal zone, it can be drawn back into the water and moved along the beach by currents or drawn out into the ocean by very high waves. We see this in most winters, when high surf removes the wide flat summer beach, and changes it to a narrow slope that starts in or near the vegetation line.  Most of that sand goes into the surf zone and moves north along the beach during the winter. Some of it comes back onshore the next summer in a new location. Some of the sand moves west into deeper water, and stays there. 

Second, some of the sand on the beach blows into the dunes, the vegetated area, where it builds up the form of the dune. There’s a geologic term for this, of course, which is saltation, the movement of fine mineral grains by wind in bounces over a surface.

Originally used as an illustration of black sand on a winter beach, this also shows sand blowing from left to right into the dunes, to build up the elevation and the width of the fore dune––the dune immediately adjacent to the beach. 

In summer, strong northwesterly winds blow dry sand along the open flats and up into the dunes. In winter, with strong winds from southerly directions, sand is also blown/washed into the dunes, some of it carried on salt spray or at the surf edge. I haven’t set out measuring sticks to see which season’s winds (summer or winter) move more sand, but one big storm can deposit six inches of sand on a dune top.  From the air it looks like a water cannon plastered the dunes with sand slurry. The net effect is to build a dune at an angle to both wind directions, one that parallels the beach. 

Third, some sand is used for construction, to sand cranberry bogs, and land filling. It’s usually scraped up near beach approaches and outfalls, and hauled off by truck. In a typical year, about a million cubic yards of sand is hauled off the local beach. This sand moves permanently out of beach circulation and nearby dune building processes, or as permanently as our sand spit stays above sea level. 

Winter storms blow build fresh layers of black sand into dunes over beachgrasses, at Benson Beach, Cape Disappointment State Park.  Next spring these grasses will send rhizomes into the sand and bind it, while their leaves sprout above the new level. 

There’s often a visual difference in summer-wind-deposited sand versus winter-storm-deposited sand.  Summer sands are light-colored, light-weight, and high in quartz and feldspar. Winter sands may include darker, heavier sands, which have iron and manganese grains. Winter sands layer up like dark frosting over vanilla cake, with black sands atop the lighter-colored summer sands. 

One of the striking impacts of Hurricane Sandy on East Coast shorelines in 2012 was the fate of hundreds of miles of beaches. These beaches went away, washed over their barrier spits inland, into the bays behind, or dragged back out to sea. Many were built from sands mined from deeper waters by dredges, and deposited onshore. When Sandy hit, there wasn’t enough sand in the nearshore to keep the beaches or dunes intact in storm surf or surges. Luckily for us, we don’t have this problem.  Despite dams on the Columbia River that trap sediments, and dredging, which usually deposits the sand in deeper water than surf can pick up, there’s still considerable sand in the surf zone along most of our beach.  The proof of this is in the ongoing build-out and –up of dunes along the beach. 

Building Dunes Part 2:  Dunes As Seawalls

We are lucky to have healthy outer dunes and ample sand on the beach and in the surfzone to build and maintain them.  Our dunes aren’t just pretty places to walk and live. These dunes also form a seawall, a protective barrier between our communities and the ocean. Recent tsunamis in Japan and other countries have an important lesson to teach those who live along the ocean:  the higher and more continuous the seawall, the better the protection is for that community from storms and tsunamis. 

There is a second lesson to be learned from the recent tsunamis in Japan:  no seawall can be high enough.  Whatever the planners and engineers estimate is high enough, is probably not. Go higher.  We do not have to do this ourselves with bulldozers or shovels. With ample sand, onshore winds, beachgrasses and sand trapping structures, nature will build the seawall higher. She just needs sand and time.  All the basic aids to dune building are already here. 

Remnants of a wood fence at Benson Beach, Cape Disappointment State Park, placed by the US Army Corps of Engineers for a beach enhancement trial, where dredged sands from the Columbia River Entrance were directly placed on the beach above the tideline to build up an eroding section north of the north jetty. The fencing helps slow and hold sand, but erosion during winter storms continues to eat away at the sand each year. The lower 3-5 miles of beach is one area that is moving eastward and eroding, while most beaches to the north continue to grow up and westward.

Our onshore winds are legendary, and being eyed by wind and wave energy firms as power generating sources. Two introduced beachgrasses grow on the dunes, American and European beachgrass (Ammophila breviligulata and A. arenaria, respectively); each species does a good job of binding sand that blows into the dunes from the ocean beach. 

To build dunes up, winds blow the sand up into the dunes, sand fencing or beachgrasses slow the winds at the top, and the sand grains drop out over the crest of the dune. Then beachgrasses grow into the loose sand and bind it.  Low narrow dunes become broad higher dunes over several years. 

Sand fencing has been in widespread use along East Coast beaches for many years. This summer, there will be thousands of feet of new fencing in place on many beaches, to start rebuilding those storm-eroded dunes, badly damaged in Hurricane Sandy last fall. Sand fencing needs some tending, resetting the posts and lifting the fencing every year or so to keep the fencing in the air. Over time, it’s a simple, inexpensive and effective way to build broad high dunes. 

There’s one more problem to attend to:  The gaps in the seawall.  Approach roads that cut through dunes are gaps in the seawall.  Sloughs that drain across the beach through dune cuts are gaps in the seawall.  Dunes lowered for the view are gaps. Collectively, these become access paths for storm surges and tsunamis. Any breach in the dune is a gap in the integrity of the seawall.  

Beachgrassses, sand and time can close all these breaks, if we let nature go to work.  Roads and access paths can go over the top of the dunes. Outfalls for storm drainage and sloughs can go through culverts under dunes instead of open cuts through them. Sand fencing can build up those areas with especially low dune crests.  

Pacific County allows, with the right permits, the maintenance of dunes at 24 ft for ocean views. Having watched videos of tsunamis overtopping a 35 ft high seawall in Japan, I’m inclined to think that our beachside dunes should be much higher.  Eight to ten feet of subsidence on a 24 ft dune produces an effective height of 14 to 16 feet after the next big subduction zone earthquake. Forty feet might be a better target height for our beachside foredunes. 

We can build up this seawall with nature’s help, so that when the next big Cascadia earthquakes and attendant tsunamis hit, we’ll have more protection in place than we have right now. This might be enough to help some of us survive to rebuild after the next big one. 

Megalodon: An ancient shark that makes the Great White Shark look small

Written February 4, 2013, published March 2013.  Photos of teeth from a private collection, all photos by Kathleen Sayce.

Many animals that formerly lived on earth have modern analogs, animals living today that look and behave very like those ancient animals, though they might not be direct descendants. It’s as though the giant cats, bears, wolves, and sharks of the world recur again and again, slightly reconfigured each time. One ancient mega-tooth shark, Megalodon (mega for big, odon for tooth) has a small analog in the great white shark. 

Great White Sharks are big as predatory sharks get today, growing to twenty feet long, weighing up to 4,200 pounds (2.1 short tons). [Some older records of much larger Great Whites are based on inferences of size and not direct measurements.] Body shape and weight of these sharks help estimate the size of fossil Megalodon skeletons. Compared to Megalodon, they are in the second tier for size: Megalodon grew to 67 feet long, and a weight of 114 short tons. 

Megalodon lived from the late Oligocene (28 million years ago) into the start of the Pleistocene (2 million years ago), for 26 million years. Great Whites first appeared during the mid Miocene, so both species overlapped for millions of years. Even when young, Megalodon Sharks were so much larger that Great Whites were probably prey. They ate fish and marine mammals when small, but when more than 40 feet long probably had to shift to whales to get enough protein with each meal. Fossil whale bones have been found with Megalodon tooth marks on them. In some cases, the sharks simply bit the whales in half. Megalodon jaws were up to seven feet wide when open, large enough for a tall man to stand inside, so they could easily catch and eat whales.  Today, a Great White Shark can eat a Harbor Seal in two or three bites. The equivalent for an adult Megalodon was eating a Gray Whale in two or three bites. 

Fossil Megalodon teeth have a characteristic wide triangular shape and serrated edge. All were collected near Bakersfield, Cal. and are in a private collection. 

Megalodon teeth were known long before skeletal fossils were found. Sharks grow many teeth over each life, growing, shedding and replacing them continuously, several hundred teeth per shark. Already hard, teeth easily fossilize, and can be found millions of years later. Megalodon teeth are large, up to seven inches from base to tip, and serrated to improve slicing ability. They turn up in rocks, in marine sediments, and in soils all over the world. Initially they were thought to be fossil dragon or snake tongues, and were called glossopetrae, or tongue stones.  During the late Renaissance a Danish naturalist named Nicolaus Steno correctly identified these as fossil shark teeth. 

From these widespread fossils, found all over the world, we know that Megalodon were cosmopolitan, living throughout the world’s oceans. Like all top predators, their presence determined the structure of the marine communities in which they fed. As they grew, they moved from small to large fish, to marine mammals like seals and porpoises, and then to larger and larger whales. 

This Megalodon tooth is almost five inches wide and tall; the largest teeth known for this species are seven inches tall. Next to it, a fossil Mako shark tooth is two inches tall. Great White Sharks have teeth similar in size to Makos, up to two and one half inches tall. 

The first glacial maximum of the Pleistocene, with shrinking oceans, falling sea levels, and expanding ice sheets, also reduced whale populations due to changes in nutrient cycling that affected the entire food web. These changes left large Megalodon adults starved for food, and impacted the warm shallow seas where juvenile Megalodon lived. Many shallow seas simply drained away as more and more water was locked up on land in continental and montane glaciers. Great White Sharks, being much smaller, with less than one third the length and one fiftieth the body mass of Megalodon, adapted to these changes and survived in colder oceans with smaller prey.   

A small tooth (1.5 inches wide) shows the serrated tooth edge that is distinctive to Megalodon, and which gave it good slashing ability. 

The tooth that was photographed for this article came from California, and was found east of Bakersfield by a private collector. At one time the area was a large shallow sea, and it is known for a large variety of marine fossils. So far as I know, Megalodon fossils have not yet been found in Pacific County. If someone has a Megalodon tooth from this area, I would like to know about it, and I promise to keep your name out of the paper. 

However, we can deduce the historic presence of this great mega-tooth shark without local fossils.  For many millions of years this area was under water, first as deep ocean and later as an ever shallower warm sea.  Megalodon Sharks swam over this part of the planet for millions of years. We see modern Great White Sharks as awesome for their size, speed and predatory behavior. Yet Megalodon was a shark that other sharks avoided, including Great Whites, because they too were food for this top predator. 

Roof residents, or where green is not necessarily good

Written January 21, 2013, published in late January, 2013, all photos by Kathleen Sayce

Several species arrive quickly on suitable roofs, starting with algae and bacteria. Algae are tiny plants that are so small and light that their spores blow through the air. These come in several colors, including green, red, orange and golden brown, and also live on trees. Black stains on asphalt shingle roofs are usually photosynthetic bacteria, as are olive brown globs and bubbles that can make the roof appear to be buried in gelatinous slime. 

Two species of moss share space on an asphalt roof with a brown-black cyanobacteria, Nostoc commune. The mosses are seen year round; this bacteria appears in late fall on suitable roofs. 

Lichens and mosses soon follow, and are also tree inhabitants. Lichens may be inconspicuous for a couple of years before they are big enough to form more than a thin gray or black film, but mosses go from thin green films to tidy clumps in one year.  The moment mosses form moisture-holding tufts of green, gray, gold and silver, worms and other invertebrates arrive to live under them. Have you ever seen a crow walking a gutter or a roof, turning over moss clumps? That crow is hunting for juicy protein-rich worms. Tiny beetles, other insects, springtails, millipedes, tardigrades, isopods and other tiny animals also live in the mosses, and yes, these species also live on trees. 

Two mosses grow together on a roof. One is starting to produce spores (the red stalks will grow spores in a few weeks); this is a cosmopolitan moss, Ceratodon purpureum. 

Roof occupancy does not stop at algae, lichens and mosses, and invertebrates. As leaf litter builds, humus forms on roofs and in gutters, and ferns and plants with seeds that float in the air show up.  On well-mossed roofs I’ve seen massive clumps of Licorice Fern (Polypodium glycrrhiza), along with Willowherbs, Cat’s-ear and Dandelion. These plants all have seeds or spores that float on the air, so it’s no surprise that they are easily lofted to a roof. Sitka spruce and red alder have seeds with small wings that blow on the wind, as I realized the year I pulled five spruce seedlings from a gutter full of compost.  In my defense, I’d sprained an ankle the prior summer, and did not climb ladders for more than a year. That was all it took to fill the gutters with conifer needles, for those needles to form compost, and for spruce seeds to arrive and germinate. 

Cyanobacteria, Nostoc commune, forms thick gelatinous masses on roofs among leaf litter and moss patches. 

For heavier seeds, there are birds to carry seeds; they eat the fruits and poop the seeds out high in trees, on favorite perches by bird baths, and on roofs. On a well-thatched roof, thick with natural leaf litter and mosses, grow holly, ivy, blackberry, elderberry, black currant, trailing currant, salmonberry, thimbleberry,  and twinberry, to name just a few local species that often end up on poorly tended roofs. 

This healthy clump of moss had three worms living beneath it when it was turned over. 

Why cleaning is necessary

Mosses have small proto-roots that exude weak acids to eat into bark and help anchor the plant. These same acids eat into and through asphalt and wood shingle roofs, which unlike trees don’t keep growing new surfaces under the bark. The roof dissolution process takes years; eventually, the shingle is riddled with holes. Now, when it rains, the water drains into the building instead of down the roof to the gutters. Wood fungi, termites and carpenter ants take up occupancy in the damp wood under the roof. At that point, your house is toast, unless you replace the roof and rebuild damaged structural elements.  

Birds don’t help, either. Where birds like to congregate, bird poop falls, and this feeds plants. A favorite roof-roost for pigeons, for example, will grow impressive moss and lichen patches down slope from the roost. Bird poop is corrosive, and will help roofing material surfaces to break down quickly. There are many devices to keep birds from settling on roofs:  Rows of ridgetop spikes and spines; rolls of spiky-spiny wire; long flexible wire spines to go between standing seams on metal roofs; bird-scarers, like large plastic owls; and whirly-gigs with bright reflective sections. 

The simplest way to reduce these problems on roofs is to not let them start:  Keep the roof clean; every year or two clean it off.  Don’t forget walls, window frames, decks and steps. These species aren’t fussy; they’ll grow anywhere there’s enough moisture, and too little disturbance. If you want your roof to last, mosses, leaf litter, and their companions have to go. 

Some people clean during the dry season, others during the wet season. My father waited to clean gutters during the first rains each fall. As a child, I thought everyone cleaned gutters in the rain. I prefer midsummer myself, when the roof is dry and the air is warm. Some people put down copper or zinc flashing or spread zinc powder; these metal salts are toxic to mosses, lichens and algae. As metal salts wash down the roof, they kill the plants and fungi. Others wash roofs, and then during the dry season, spray on a layer of detergent. The detergent kills germinating spores and young plants of algae, lichens and mosses. It must be redone every two or three years.  You still have to check gutters, downspouts, and subsurface storm drains, if you have these. 

No matter which method you use, be safe. Set ladders properly on level firm ground. Have a safety spotter on the ground. Don’t work on slippery wet roofs––wait for dry weather. If you must be on a roof when it’s wet, use a safety harness. Wear sturdy boots with gripping soles. Put the cell phone aside until you are back on the ground. Your reward is a roof that may last for most of its planned design life, instead of being replaced decades too soon. 

Broadening Organic: Nutrient Dense Foods

Written January 4, 2013, published in mid January 2013. All photos by Kathleen Sayce.

The debate about organic versus convention food production goes back and forth. One study says organically grown food is healthier. Another says there is no difference in nutritional value between organically- and conventionally-grown foods, except for the level of pesticides. No surprise, organic foods have lower pesticide levels. A third says that soil amendment costs are higher on conventional farms, lower on organic farms. Another says labor costs are higher on organic farms due to more hand weeding. Organic food gardens cost less to operate, because fewer amendments (fertilizers, pesticides) are used, and less water is needed. Conventional food gardens produce more food for lower labor costs, but at higher health risks for farm workers due to pesticide use. 

A refractometer with three kale samples, from left to right, Red Russian, Red Curly and Green Curly Kales. 

Food Quality

What’s a home gardener to conclude from this argument? I say:  Expand your definition of organic gardening and look at food quality, specifically at nutrient density:  What form of gardening produces the most nutrient dense food?  ‘Properly mineralized soil’ is the correct answer. This goes beyond avoiding crunchy, sugary, salty processed foods, as good as these taste, to plant and animal foods with high quantities of minerals, proteins, fats, sugars and secondary compounds. This is nutrient density, which we can measure, and more importantly, we can taste.  

Plants grown on optimally healthy soils have higher levels of dissolved solids and minerals in their intercellular sap than do those grown conventionally or on nutritionally out-of-balance soils, regardless of the management method for that soil. These plants are healthier, and their roots, fruits and leaves and stems, which we eat as foods, are more nutrient dense.  They deliver optimal food quality and flavor to us, the eaters.  Likewise, animals grazed on pastures managed for optimal nutritional health are healthier. 

A light orange carrot with mashed fresh carrot in cheesecloth, ready to measure the carrot's juice in the refractometer.

Nutrient Density

Density is measured as dissolved solids in plant juices using a refractometer, a centuries-old device that uses refraction of light to measure fluid concentrations in Brix units. A bar of color crosses a numerical scale; you read the number on the scale. This is the Brix of that solution.  In measures of plant sap quality, the higher the Brix, the better. 

Wine, cheese and juice makers use refractometers to measure Brix and determine ripeness in grapes, tomatoes, berries, and other fruits, because there is a strong correlation between the level of dissolved solids in intercellular sap, and the sugar levels and flavor of the fruit. They often eat the fruits to compare flavor to Brix units, calibrating their sense of taste to these measurements.  Yes, you can taste the differences. High Brix fruits have more flavor. I use my garlic press to mush fresh veggies, and a bit of cheesecloth to squeeze the juice from the crushed sample to test. 

Studies of food quality rarely include the Brix levels of plant saps. Those few studies that do so show that fruits, grains, seeds, and vegetables grown on healthy soils with optimal nutrient balances have higher Brix levels than do conventionally grown foods on unbalanced soils.  

A green curly kale sample in cheesecloth with bright green fresh juice.

Food Quality, Flavor and Health

As consumers of mass-produced foods, many of us have never tasted these flavor differences, due to lack of exposure to truly nutrient dense food. Bring on the compost, humus and biochar, and soil tests for minerals, so that we can determine exactly which minerals our vegetable gardens need. In a healthy soil with optimal levels of nutrients, all of those plants, including fruit vines and shrubs, peas, carrots, beans and even lettuces, will nosh in style, and deliver more nutrition and flavor.  

The result of eating plants grown with optimal soil nutrition is that we can be healthier. So step aside of the arguments about conventional versus organic, and go beyond, into an expanded definition of organic gardening with nutritionally complete soils, with regular soil tests, appropriate mineral supplements, and grow healthier plants. Get optimal flavor, high mineral levels, and higher levels of sugars, proteins, fats and other flavorful compounds. 

Anyone can do this. Gardening is not difficult; it takes time, and soil tests to determine what amendments your soil needs to optimize nutrition for your home garden, orchards, lawn or pasture. The gain is in taste and health.  Steve Solomon’s latest book, The Intelligent Gardener, discusses soil nutrition for growing optimally healthy foods in sufficient detail to get you started. 

Winter is a great time to be planning next year’s vegetable garden. Order soil tests, then add the right minerals to improve your soil, for great eating next summer. Summer is coming, right? The rain will end sometime, right? 

A red curly kale sample with its red-purple colored fresh juice. The chlorophyll is in there, but masked by the reds and purples of the red kale plant. 

Healthy Soils for Healthy Vegetables

Written December 12, 2012, published in late December, 2012, all photographs by Kathleen Sayce

Soil health for vegetable gardens is more precise than for ornamental gardens and native plants. Most vegetables are annuals or biennials, living only one year, or over one winter.  All of are from other places and climates, with nutrient and soil needs considerably different than local soils can provide. Vegetable plants need:  Deep, open, well-aerated soils with soil carbon, diverse minerals, sunlight, warmth and regular water. With these, they grow quickly into tender, nutritious and edible foods; without them, vegetable plants struggle, easily fall ill, and fail to thrive. Vegetables generally are not shade plants, especially along the raincoast; warmth and regular watering are needed for vegetables to grow well. 

Well-grown vegetables are able to resist weather, diseases, insect pests, and have high levels of minerals, proteins and other plant compounds. This photo of Red Russian Kale was taken in Jim Karnofski’s vegetable garden by Kathleen Sayce.

Soil Carbon

As with other kinds of plants, vegetable plants need soil carbon. The forms that are the most usable for vegetable plants are not aged wood chips or forest debris, but well prepared compost with humus, and biochar (biologically activated charcoal). Vegetable plants use soil carbon throughout their root growing areas, so gardening practices for optimal plant nutrition incorporate carbon of several kinds throughout the soil profile. Gardeners work carbon into the soil with a rototiller or shovel, add layers to the surface, side dress plants, and amend planting holes. They also fallow garden sections every few years, planting cover crops to put more carbon back into the soil. 

Carbon promotes soil health by giving soil organisms food to eat (carbon) and places to live (cellulose scaffolding). The one drawback is that, being formed of cellulose (wood), most forms of compost break down quickly. So gardeners need to add compost regularly, year after year. Only humus, a brown, clean-smelling, somewhat sticky substance, persists for decades to centuries in soil. Compost piles can form humus if clay and local soil are added to each layer. 

Compost with charcoal added is dark colored, and is now ready to go into the vegetable garden.  Photo of one of Jim Karnofski’s compost bins.  

A second soil carbon material, biochar, is charcoal that has been activated with compost or soil microbes. Biochar has an advantage as a soil amendment: charcoal is stable in soils for centuries to millennia. When gardeners add biochar, this is a permanent improvement in the soil. Add biochar along with compost, and over time, you will have the same productivity with less compost. 

Making Biochar

When wood is burned, charcoal is formed during the burning process. If burning is complete, the wood goes to charcoal and then to ash. Starving the fire of oxygen (a process called pyrolysis) promotes charcoal formation and keeps the fire from consuming all the wood. Innovative pyrolysis burners are being developed at backyard and industrial scales to produce large amounts of charcoal with minimal amounts of ash. When the charcoal is wet and cold, it can be added to compost to be inoculated. See  HYPERLINK "http://www.biochar-international.org/" http://www.biochar-international.org/ for biochar producing devices. A short video for an introduction to home charcoal making is on You Tube at  HYPERLINK "http://www.youtube.com/watch?v=dqkWYM7rYpU" http://www.youtube.com/watch?v=dqkWYM7rYpU .

Freshly made charcoal is ready to go into the compost pile when it is wet and cold, and broken into small pieces. 

Mineral Nutrition

The second soil management practice for optimally healthy soils is to use soil tests to determine what minerals are needed, and then to add those missing minerals in the correct amounts. Soil tests are inexpensive, and a simple way to ensure a garden is not over-fertilized with some minerals and too low in others. It’s a good gardening practice to test soils in your vegetable garden and adjust your fertilizer program every year. Minerals can be added as rock dusts, algae extracts, and other forms.  The differences in terms of productivity can be staggering; I’m not talking ten percent increases or even twenty. At times, improvements can be on the order of multiples, as measured by plant weights or volumes, fifty pounds of potatoes instead of twenty, for example.  

Jim Karnofski, local vegetable gardener and retired nurse, has delved into soil mineral nutrition as a neighborhood soil analyst, and is wiling to teach anyone interested in learning the details how to decipher soil test results. He also makes custom nutrient blends for specific soils. I tested my soils a few weeks ago, after years of adding carbon, trace minerals, and organic fertilizer blends. I found that my soils are surprisingly low in boron, manganese, sodium, copper and sulfur. Jim composed a custom blend to meet the nutritional deficiencies based on the soil test. I’ll add a portion of these missing nutrients every few months, test again in coming years, and keep adjusting minerals to improve my soil. A new book by Steve Solomon, The Intelligent Gardener: Growing Nutrient-dense Food, goes into splendid detail about vegetable nutrition. 

The sum of all of these actions (adding carbon, testing soils and adding mineral nutrients) is to have optimally healthy soils. Healthy soils produce healthy plants, able to resist disease, drought and insect predation. In turn, healthy plants produce nutrient-dense vegetables and fruits, which are better foods for us.  Many chronic human health conditions go away when people make the change to eating fruits and vegetables grown on optimally healthy soils. I think we’d all like to live healthier lives, and my personal task for the New Year is to promote soil health, so as to promote human health.