Category Archives: farming

May: It Rhymes With Hay

When I told WWOOFer Meg I was going to put up a blog post about recent weeks, she suggested it simply be the word “HAY!”  It was tempting.

We’ve been busting out row after row of thick hay mulch, keeping the ravaging hordes of weeds suppressed while the crops get their feet under them; it holds moisture in the sandy soil, and eventually breaks down, adding nutrients and much needed organic matter for future crops. It’s not the most pleasant of tasks, especially for those of us with hay and mold allergies, but we’ve gotten some pretty good tactics down to make it easier; one person with a wheelbarrow per row to be mulched, doing relays back and forth, while one or two people rip up bales outside the field, and load up the wheelbarrows when they return, empty, to the fence.

This process has made things much more efficient, and since we’ve had a few WWOOFers helping, we’ve managed to get much more of the field under cover than previous years … which will mean happier crops and less weeding for the rest of the season.

tortiseshell haymulch
tortoiseshell hay mulch

In a similar vein, we found a free silage tarp the exact dimensions of our high tunnel greenhouse, while scavenging for useful items at the annual “Trash Days” in Bloomington MN (where folks put all manner of unwanted piles out on the curb for scavengers like us to pick through, prior to it all heading to a landfill). Although it hadn’t been the plan, the dimensional match seemed too meant to be to ignore, so we transformed the high tunnel into a plastic bubble for heat-loving plants.

It’s amusing since neither of us really ever wanted to grow using plastic, but it’s hard to argue with luck and with results – and it’s certain that such a ground cover is ideal for the sandy, weedy soils we contend with here, as well as for heat-loving plants. (The plants are watered by both driplines connected to the well, and by soaker hoses gravity-fed by various rainwater collection tanks around the farm.)

sweeping the loose soil away from the sensitive tomato plants. Tomatoes are total Bubble Boys
sweeping the loose soil away from the sensitive tomato plants. Tomatoes are total Bubble Boys

And speaking of rain – we’re finally getting nice amounts, after a nearly month-long dry spell, where we were having to run the generator/well irrigation daily to keep the seeds and transplants alive in the field. We’d watched storm after storm split apart on the radar and pass around us, leaving us dry … but finally, we were blessed with three inches over the course of a few day rainy spell (an amount that would have been problematic in less well-drained soil), and since then it’s been a lovely syncopation of sunshine and rain, alternating daily or even hourly.

the crew unloading a trailerful of free woodchips
the crew unloading a trailerful of free woodchips

As I sit writing this on Monday morning, it’s going from full sun to downpour about every 10 minutes – the photo above is the sunny field with the next squall rolling in.

The crops love this rhythm, and are looking quite pleased with their lot in life.

cloudy weather kept us from properly hardening-off the tomato plants to the sun - so of course as soon as we transplanted them out, the weather left the forecasted script and went full blazing sunshine ... we spared the tomatoes from the strongest rays with suspended row cover fabric
cloudy weather kept us from properly hardening-off the tomato plants to the sun – so of course as soon as we transplanted them out, the weather left the forecasted script and went full blazing sunshine … we spared the tomatoes from the strongest rays with suspended row cover fabric

 

The mulch has unfortunately provided habitat for our population of tunneling colonial vegetarian rodent-monsters (aka voles), however we have been heartened by the influx of snakes around the field this spring – the hugelkultur mound, for example, had been nicknamed the “Vole Hotel” last year, as it was clear they’d infested the spaces between the buried branches and logs. When we got to work this spring, we noticed the holes into the mound seemed larger, and feared it meant even MORE voles … soon enough, however, we saw the huge gopher snakes cruising in and out, basking atop the mount in the sun, breeding in the grass, and hopefully striking terror and population control into the resident rodents.

snake sex! We hope for many babies.
snake sex! We hope for many babies.

We’ve been reconnecting with our human network as well – spending plenty of time with our friends, supporters, and neighbors, the Marquardts, meeting up with local historian and author Russ Hanson (he gave us an old coal boiler that we’ve turned into a wood-fired water heater), and taking the poop pile from our new goat-mancer friends and CSA members at The Munch Bunch.  And we’ll be starting to sell at the Saint Croix Falls Farmers’ Market in a week or two … a few weeks after the market begins, as usual.

the wood-fired water heater, ready to provide up to 20 gallons of hot water every day. Made from a 1930's Sears "bucket-a-day" coal boiler and a modern Sears water heater tank. The fire and gravity work together to circulate the water without a pump.
the wood-fired water heater, ready to provide up to 20 gallons of hot water every day. Made from a 1930’s Sears “bucket-a-day” coal boiler and a modern Sears water heater tank. The fire and gravity work together to circulate the water without a pump.

(We simply don’t have enough growing this early in the season for our attendance to make sense, especially alongside those coming in from south of here. Heck, we even have a slower start than other farms in the same township as us – the local historian let us know that his growing season, up the hill, is a full month longer than ours is, due to the way cold air settles into the wide glacial Saint Croix River valley where we grow!)

lettuce, beets, and kohlrabi
lettuce, beets, and kohlrabi

The biggest change afoot this spring is all around us, and it’s been a real test of our ability to “que sera, sera” with inevitable change – logging. Starting at 7 am, for weeks, we’ve been greeted by the sounds of the profit-driven logging machines devouring all the largest and oldest trees in the vicinity, and leaving arboreal carnage in their wake.

the north side of the farm has already been logged - you can probably guess where our property line is ...
the north side of the farm has already been logged – you can probably guess where our property line is …

I could rant, here; there is much to be angry, sad, and disappointed by, seeing how callously these woods are turned into dollars for the Wisconsin General Fund … especially knowing that next year it will likely be the patch of woods right alongside our driveway that is razed.

the loggers "spare" a few token trees here and there, but they never fare well after having all their neighhbors removed and their roots run over repeatedly.
the loggers “spare” a few token trees here and there, but they never fare well after having all their neighhbors removed and their roots run over repeatedly.

But I won’t rant. It’s one of those things that we cannot change, and must find peace with at minimum, and even better, silver linings. In this case, we will have ample access to the remnants the loggers leave behind, for use in our heating needs, and we expect that the suddenly-opened areas will allow understory fruit bushes to spring into productivity, producing wild raspberries, blackberries, and blueberries.

excavating the ruins ahead of the loggers
excavating the frosted ruins, ahead of the loggers

Another silver lining –  although no one had told us, I had a hunch that the loggers were coming to the neighborhood – and launched a salvage expedition to recover the last of the old car body panels from the homestead ruins of “The Architect” … and just days later, the whole site was crushed by heavy machinery treads. Sad – but awesome that we salvaged the remains in the nick of time, to repurpose for future projects that have local historical roots, as well as powerful aesthetic appeal (to our eyes anyway!)

aftermath of the logging crews
aftermath of the logging crews

Widget with a model-T body panel run over by a bulldozer
Widget with a model-T body panel run over by a bulldozer

We’ve enjoyed feeling like we lived in a forest, but with the surrounding woods logged, we’ll be well-aware that we truly live in The Barrens, and we that we grow food in an area considered to be little more than a wasteland by many. Underappreciated, scruffy places on the outskirts of human civilization has long been our favored type of habitat, and that’s exactly where we are putting down our roots; deep tap roots that can draw sustenance from the most unpromising-looking sands.

No matter what, it’s going to be interesting, and interesting is our favorite thing.

So.

The first CSA box will be coming on June 6th … are you ready? We are!

See you soon,

Gabe & Kristin

morel captured
morel captured

oyster mushrooms on a stick
oyster mushrooms on a stick

 

HEY HAY MAY PICS

building the tomato trellises
building the tomato trellises

the monster on the left had two yolks
the monster on the left had two yolks

 

killing quack grass - first loosening the soil with a broadfork, and then carefully digging the extensive root systems out by hand.
killing quack grass – first loosening the soil with a broadfork, and then carefully digging the extensive root systems out by hand.

WWOOFer woofer Kingsbury likes to find and bring home pieces of deer ... so pleased with himself!
WWOOFer woofer Kingsbury likes to find and bring home pieces of deer … so pleased with himself!

grapevines coming to life
grapevines coming to life

we took several bucketfuls of quack grass rhizomes out that day ... the weed bloodlust was strong.
we took several bucketfuls of quack grass rhizomes out that day … the weed bloodlust was strong.

Widget helps weed the raspberry patch
Widget ‘helps’ weed the raspberry patch

Elden pots up pepper plants
Elden pots up pepper plants

a box turtle came to visit
a box turtle came to visit

Kristin and her dad working on the screen porch roof
Kristin and her dad working on the screen porch roof

chive flowers
chive flowers

Jim helps install the new solar panels
Jim helps install the new solar panels

laying irrigation lines
laying irrigation lines

babies
babies

the eroding pipe of greenhouse heater's booster fire makes for some beauty
the eroding pipe of greenhouse heater’s booster fire makes for some beauty

 

And finally, let’s cap May off with a few good versions of our farm’s theme song!

(High Keys is my current favorite version. The Lords version is awesome for the band’s dancing lol)


Hibernation to Germination 2017

Widget requests picking up
Widget requests picking up

Three days ago, I packed up all my wool blend socks, sweaters, long underwear, and winter boots.

some of the new chickens had never been outside before coming here. they thought that the snow was lava and went to ridiculous lengths to avoid touching it
some of the new chickens had never been outside before coming here. they thought that the snow was lava and went to ridiculous lengths to avoid touching it

I was feeling optimistic, and perhaps hoping that by taking this step I would help do my part to ensure that winter goes away for the year. I’ve been premature in my Spring-faith before – even just earlier this month a wet, heavy snow took out the gutter I’d eagerly reinstalled on the side of our high tunnel greenhouse, hoping to collect some early rainwater for the first high tunnel crops.

snow cover from inside the greenhouse
snow cover from inside the greenhouse

So I shouldn’t have been surprised when this cold snap hit – highs in the 30s, lows in the 20s. I just finished putting sheets and buckets over the raspberry canes, rhubarb, and asparagus, which are apparently just as foolishly optimistic as I.

But even with more snow and cold, it’s indubitably Spring, albeit USDA Zone 4a style. Nature’s signs are everywhere – the evening choruses of peepers have returned, the evil quack grass is lushly taunting me, we’ve had our first tick and mosquito bites, and the hungry black bears have begun their raids on the Neighbors’ birdhouses.

emerging rhubarb brain
emerging rhubarb brain

Robins are twitterpating, dandelions blooming, rhubarb and asparagus emerging from their subterranean winter slumber.

frost bow arcs over the newly-fenced field (electric polytape for the deer, and chickenwire beneath for the rabbits and raccoons)
frost bow arcs over the newly-fenced field (electric polytape for the deer, and chickenwire beneath for the rabbits and raccoons)

Human signs of Spring abound as well – we have the fence up around the field to defend against critters great and small, the loggers are back to ravaging the surround forests, and we joined the annual horde of scavengers to Bloomington’s Curbside Pickup days to get free materials for the farm.

a good haul of materials for the farm, thanks to the annual Curbside Pickup in Bloomington MN
a good haul of materials for the farm, thanks to the annual Curbside Pickup in Bloomington MN

 

The first big push of seeds are all done germinating, and have now moved out of the trailer (where we kept them toasty near our woodstove), and into the greenhouse.

In there, the seedlings get ample sunlight during the days, and the hot weather plants (peppers, tomatoes, etc) stay warm overnights on the rocket-heater-warmed clay bench (we’ve improved our firing routine such that they’re enjoying temperatures around 30 degrees warmer than outside, all night long).

firing the rocket mass heater for a night of warmth
firing the rocket mass heater for a night of warmth

using an infrared sensor to read the top of the barrel temp (at these high end temps, the center of the lid glows faintly although you can't see it here)
using an infrared sensor to read the top of the barrel temp (at these high end temps, the center of the lid glows faintly although you can’t see it here)

 

warm season crops snug under cover on the heated bench, while more hardy cool weather crops hang out in the nude
warm season crops snug under cover on the heated bench, while more hardy cool weather crops hang out in the nude

The first rows were planted in the high tunnel a couple of weeks ago – reluctantly, since we discovered that rabbits have been partying in there through the nights, and we feared devastation … but a combination of scent deterrents, homemade hot pepper spray, and wire fencing seems to have moved them on to less hostile environments.

skulking rabbit in the high tunnel
skulking rabbit in the high tunnel

 

In the last couple of days, the first field plants went into the ground, ready to soak up the days of rain that followed – peas, salad mix, turnips, radishes.

In other news, we’ve doing lots of spring cleaning around the farm, building a larger screen porch in preparation for the annual mosquito blood- drive, clearing out a patch of large oak-wilted trees to make room to plant new fruit trees (and to make firewood of course), plugging new mushroom logs, using the chickens to break down our abundant piles of oak leaves for use in compost, and experimenting with controlled burns in the meadows and woods on the margins of the field.

 

Holy shiitake! The logs we plugged two years ago are putting out tons of delicious mushrooms
Holy shiitake! The logs we plugged two years ago are putting out tons of delicious mushrooms

fresh shiitakes & fresh eggs with spicy noodle leftovers
fresh shiitakes & fresh eggs with spicy noodle leftovers

Sehr family project - Kristin with Matriarch and Patriarch Sehr, working on the expanded and improved screen porch
Sehr family project – Kristin with Matriarch and Patriarch Sehr, working on the expanded and improved screen porch

Eugene helping with the screen porch roof
Eugene helping with the screen porch roof

 

froooooost on the gaaaaaarlic (dum dum-dum, dum-dum dum dum, dum-dum dum, dumm dummmm!)
froooooost on the gaaaaaarlic (dum dum-dum, dum-dum dum dum, dum-dum dum, dumm dummmm!)

hens checking out the fresh;y-tilled soil. Hope they devoured some cutworms
hens checking out the fresh;y-tilled soil. Hope they devoured some cutworms



down, down, down in a burning ring of fire
down, down, down in a burning ring of fire

Fire Marshal Neighbor Marcia supervises one of our burns
Fire Marshal Neighbor Marcia supervises one of our burns

 

We’ve battled quack grass, spotted a fisher (a giant weasel basically), cursed the insanely-intelligent voles … and sat inside on a chilly gray day and finished this webpage update for you.

Rain and sleet cannot dampen Kristin's commitment to her post running the booster fire for the greenhouse, as we charge up the thermal mass to keep the warm season seedlings toasty through a night in the 20s
Rain and sleet cannot dampen Kristin’s commitment to her post running the booster fire for the greenhouse, as we charge up the thermal mass to keep the warm season seedlings toasty through a night in the 20s

if you look very closely, you can see me at the far end of the row, working the broadfork
if you look very closely, you can see me at the far end of the row, working the broadfork

freshly-tilled and ready to rock!
freshly-tilled and ready to rock!

Hope you, too, are enjoying this slow, beautiful transformation from winter to spring! Life is strange and beautiful, and the struggle is the joy … we’re grateful to have such lucky abundance, such interesting problems. and such folks as you in our lives. Thanks!

 

the Way to May – CSA Pre-Season Newsletter

IMG_4341

Holy wow, it’s already well into May! Signs of the season surround us, reminding us just how lively this landscape is …  greenery is bursting forth from every tree, every patch of earth.

IMG_5326

 

Our apple and pear trees are blooming, as are the trillium, violets, and wild plum trees. The perennials are coming up – chives, rhubarb, raspberry, mint, lemon balm … and we ate our first fresh asparagus of the season last week.

after a full day working in the 90 degree sunshine, a dip in the Saint Croix was refreshingly perfectly chilly
after a full day working in the 90 degree sunshine, a dip in the Saint Croix was refreshingly perfectly chilly

Throughout the nights, mystery critters crunch through the undergrowth or scramble across our trailer, coyotes caterwaul in chorus, barred owls demand to know “who cooks for you?“,  and once in a while a fox or civet makes a freaky womanlike scream. My favorite night sound is the abundant whip-poor-wills – nocturnal bug-eating birds that I only hear here.

IMG_5255

The black bears are out and about, scavenging for treats  – a young male has been knocking over Neighbor Marcia’s birdfeeders, and the momma bear and her three cubs from last year were spotted in the woods behind us – the cubs are huge now, in their second year, and about ready to set out on their own.

IMG_4397

As always, Spring has been an incredibly busy time, as we get everything ready for the season. My hands are stained black with soil, and feature a wound on each palm, from ignoring Kristin’s sage advice and pounding in a row of t-posts without gloves … which led to blisters that didn’t hold up well to the continued post-pounding I subjected them to.

IMG_5367

Starting seeds, nurturing baby plants, preparing the field, keeping ourselves and the tender plants alive and warm through the chilly nights … it’s an intense time of the year, filled with all the opportunities for hope and fear that you could want!

IMG_5166 - Copy

The biggest change this year is the High Tunnel greenhouse we completed at the end of last autumn, thanks to a USDA grant.

IMG_4390

It’s a powerful and complex 72×30′ tool that we’re learning to use. After the winter, we returned to find the ground inside it totally green with grass and weeds – a beautiful lively space to hang out in, while everything outside was barren and brown! But soon enough we had to till the green under to prepare the soil for planting.

IMG_4255

We then laid out irrigation throughout – since no rain falls inside, all the plants’ water needs must be delivered by us. There are soaker hoses that are gravity-fed by our rainwater collection tanks up on the hill, and drip irrigation lines in each row, fed by the well. We’re also adding an experimental rainwater collection system on one edge … which should be able to collect over 600 gallons of water from a 1″ rainfall.

IMG_4445

We primarily plan to grow hot weather crops inside, but to get things started while nights were still going below freezing we planted some salad mix and peas. They survived the cold nights just fine – but now the challenge is to keep them from overheating during the sunny days, when temperatures in the high tunnel can easily reach triple digits if we aren’t careful. To ventilate the high tunnel, we roll up the 70-foot long side panels, permitting a cross-breeze to move through. This works pretty well, however, if it’s not merely breezy but windy (basically anything over 10mph), then we have to close at least one side up to prevent damage to the structure. It’s been a learning experience trying to balance wind minimization with heat regulation – and it will get even more interesting when the hot, sunny days of summer are upon us. (We plan to add additional ventilation in the peaks on both sides to help move hot air out even when there is no breeze.)

Nora & B help build a second chicken coop to house the 14 free craigslist hens we added to the flock in April
Nora & B help build a second chicken coop to house the 14 free craigslist hens we added to the flock in April

We’ve been very fortunate to have plenty of help this Spring. It would be a ridiculously long blog post if I tried to list it all, but I’ll try to hit some highlights …

Ace helping with some shovel work .. actually he just wants us to throw that "stick" for him
Ace helping with some shovel work .. actually he just wants us to throw that “stick” for him

Kristin’s dad Patriarch Jim Sehr has been helping us out a ton with various construction and repair projects – he added a service door to the high tunnel for far easier access, engineered the rainwater collection on there, got the riding mower working, and plumbed in our new and improved well pressure tank. And Matriarch Deb Sehr came out to cut and plant potatoes – and even do some dishes so we can stay on top of the field and construction projects.

IMG_5388

Neighbors Dave & Marcia kept our flock of hens happy throughout the winter, provided us with additional firewood to fuel both the greenhouse heater and the new WWOOFer cabin (more on that a bit), lent us gopher traps, tools, and best of all, their tractor!

turning the pile of old horse manure with Neighbor Dave's tractor
turning the pile of old horse manure with Neighbor Dave’s tractor

Plus, when I was despondent thinking I’d killed our well pump (it turned out to just be a flipped breaker in the generator), Marcia brought over rhubarb custard dessert and ice cream; I literally cannot imagine better neighbors to have.

IMG_4809

Our friends from the Cities have come out to work with us (thanks Tyler, Amy, Steffan, & Eugene!) , and we’ve had lots of help from B & Nora – the WWOOFer/musician couple that worked here throughout the end of last season, and then returned early this spring. We got a free ice fishing shack off of Craigslist – insulated and complete with a little wood stove.

IMG_4759

This turned out to be a perfect solution for them to sleep in throughout April – they helped us build it, and then made it their home – although they’d been prepared to just rough it under huge piles of blankets, the heated, insulated Fish House worked out much more pleasantly. Oh, and their Maine Coon cat, “Bucket,” is working with us too – keeping the vole population down.

IMG_5246

The field still looks pretty empty, but the first wave of food is taking root out there – potatoes, peas, onions, radishes, turnips, and various salad greens have begun to stir, stretch, yawn, and emerge into the sunshine. And of course, there are many hundreds of plants growing in the greenhouse, awaiting suitable weather to be transplanted out.

IMG_5234

The eternal battle with the evil quackgrass is back in full swing – we till or broadfork the soil of each row before planting, and then pull out as much of the tenacious, ropey, unkillable rhizomes as possible.

tilling in wood ash from the woodstove, in advance of planting beets (which appreciate the lowered ph)
tilling in wood ash from the woodstove, in advance of planting beets (which appreciate the lowered ph)

 

We’ll be using thick layers of mulch to slow down what doesn’t get pulled (it regrows from every tiny piece of root left behind) … it’s not a war that we ever really win, but we hold it at bay enough to get our crops for the year.

We give it the good fight and it reminds us that our farming here is not about efficiency … or even being reasonable.

IMG_4303

Like all of life, it’s absurd and irrational –  and we love it.

nothing beats sharing a 110 degree soak after a long work day
nothing beats a 110 degree soak after a long work day

.

Thanks for joining us in the adventure!

 

shiitake mushroom inoculated logs
shiitake mushroom inoculated logs

IMG_4351 IMG_4821

I walked away from the ladder to get hardware to hang the birdfeeder - within a minute these vultures had swooped in
I walked away from the ladder to get hardware to hang the birdfeeder – within a minute these vultures had swooped in

 

a frustrated Widget tries to chew into the tree where the red squirrel holes up
a frustrated Widget tries to chew into the tree where the red squirrel holes up

Gabe tending the rocket mass heater fire in the greenhouse by lantern light
Gabe tending the rocket mass heater fire in the greenhouse by lantern light

IMG_5385

older hends lay less often - but they lay off-the-scale huge eggs!
older hens lay less often – but they lay off-the-scale huge eggs!

IMG_4741

Quest for Fire: A Rocket Mass Heater for the Greenhouse

Being off grid (without utility hookups to water, gas, and electricity) is challenging even just for a dwelling –  but even more so for a farm, especially in this climate. In the spring, we have to start our plants indoors, so they will be developed enough to produce before it gets too hot for the cool weather plants in summer, and before the killing frosts of fall take out the heat lovers. They all need to be kept warm day and night, especially when germinating from seeds – but they also need to be under good bright sunlight. The sunlight is great in the greenhouse, which also gets plenty warm most days if it’s not totally cloudy – but greenhouses lose heat quickly after sundown. We solved for this in previous years by nightly driving all the baby plants up to the trailer, where they slept toastily on floor-to-ceiling shelving next to the wood stove.

plus trays on the front passenger seat and foot well.
plus trays on the front passenger seat and foot well.

Then every morning just after dawn, we drove them all back down to the greenhouse for their daily sunshine. We worked out a good two-person method to get it done as efficiently as possible, but it was a time-consuming process – and we couldn’t have the lights on near the plants when they were inside (or they’d get leggy trying to get fed by the artificial lighting). Yeah, it worked … but we needed to come up with something better.

Heating the greenhouse at night was the obvious solution, but it seemed impossible – the plastic covering lost heat so quickly that it would cost us a fortune in propane … and we’d always be fearful that the tank was going to run out in the night, leaving all our crops to freeze to death. And of course our little solar power system was not capable of generating enough electric heat (which is inherently inefficient) to do the job. A wood stove like the one we use in the trailer would require repeated fueling throughout the night, and again, the heat would mostly be going to the roof and then out through the plastic film.

Research led us toward a possible solution – “rocket mass heaters,” which use small amounts of wood burned efficiently at high temperatures to heat up a thermal mass, which then slowly radiates the heat outward for many hours after the fire has gone out.

Rocket-Stove-Mass-Heater

It would still be a challenge to heat the whole greenhouse with this method unless we built a prohibitively large heater, however. Hmmm.

Well, we’d already been experimenting with a technique that Elliot Coleman promotes, using row cover fabric to create a greenhouse-within-a-greenhouse – just putting the plants on the ground and covering  them inside a low tunnel of fabric kept them warmer than the surrounding air, thanks to the day’s heat in the soil. That only got us a few degrees, but it was a crucial difference when temps might be just barely dipping below freezing.

What if we did the same thing atop a thermal mass? It seemed like a winning idea – so we decided to build a heated bench sized for seed trays, and put a cover over them at night to hold heat in.

For a year, we researched and gathered materials for the build – scavenged from garbage and the Free section of Craigslist; two trailer loads of clay from a retired sculptor, stove pipe of various diameters, a 55 gallon drum, river rocks from the neighbor’s pile they’d unearthed when building their house, cement board, and bricks – the best score of all was a huge free load of white “insulative firebricks,” which withstand high heat without heating up much themselves – ideal for our purposes.

IMG_0741

Last fall, after the killing frost had come and the 2015 CSA was over, we got to work, starting to test combustion chamber designs the day after our CSA potluck.

IMG_1120

There was a long period of trying out different brick layouts – the proportions of the combustion chamber are crucial to get right – for the rest of the fall, “CSA” ceased to mean “Community Supported Agriculture,” and became ‘Cross Sectional Area” – the entire system had to maintain the same CSA throughout the system, from fuel feed to exhaust, from rectangular tunnels to round pipes. I won’t bore you with all of the proportional rules that had to be followed, but know there was a lot of subtle and annoying math at this stage.

an early mockup, seeing how tall the system would be - and how close we could put it to the curving north all of the greenhouse. (The original plan was for a 8" pipe system, although we switch to a 6" design before building)
an early mockup, seeing how tall the system would be – and how close we could put it to the curving north all of the greenhouse. (The original plan was for a 8″ pipe system, although we switched to a 6″ design before building)

 

creating a lid for a "pocket rocket" - a way to create intense fire that would burn the paint off the 55-gallon drum
creating a lid for a “pocket rocket” – a way to create intense fire that would burn the paint off the 55-gallon drum

burning the paint off of the 55 gallon drum - so it wouldn't create toxic fumes in the greenhouse later
burning the paint off of the 55 gallon drum – so it wouldn’t create toxic fumes in the greenhouse later

early layout with the larger pipes - determining how many rocks we'd want, how wide it should be for the seed trays, and how deep we'd want to make it,
early layout with the larger pipes – determining how many rocks we’d want, how wide it should be for the seed trays, and how deep we’d want to make it,

The WWOOFers joked about me playing with my blocks - I had bricks in the trailer that I'd use to try out different configurations for the heat riser ... on edge? flat? how much space inside? It was a lot more complex than I'd thought it would be ...
The WWOOFers joked about me playing with my blocks – I had bricks in the trailer that I’d use to try out different configurations for the heat riser … on edge? flat? how much space inside? It was a lot more complex than I’d thought it would be …

even in bed it was rocket heater worktime
even in bed it was rocket heater worktime

 

Many variations were tried out and discarded in the design process. The red bricks are used in the fuel feed for their durability, while the softer insulative bricks were used throughout the rest of the combustion system.

IMG_1152 IMG_1153 IMG_1155 IMG_1154

determining bench dimensions. (for awhile we thought we'd use foam insulation but wound up not doing so)
determining bench dimensions. (for awhile we thought we’d use foam insulation but wound up not doing so)

 

creating the subsurface foundation for the combustion chamber - the air spaces in the bricks add insulation to keep heat where it's wanted - not absorbing into the ground
creating the subsurface foundation for the combustion chamber – the air spaces in the bricks add insulation to keep heat where it’s wanted – not absorbing into the ground

 

IMG_1178

laying the base layer, with pits for ash cleanouts. White bricks insulate against heat loss, keeping temperatures high for the heat riser, where even the smoke will burn up
laying the base layer, with pits for ash cleanouts. White bricks insulate against heat loss, keeping temperatures high for the heat riser, where even the smoke will burn up

 

IMG_2424

constant vigilance was required to ensure that proper dimensions were maintained in all directions
constant vigilance was required to ensure that proper dimensions were maintained in all directions

IMG_1218 IMG_2456

had to learn how to score and split bricks with a chisel to make some of the puzzle fit together
had to learn how to score and split bricks with a chisel to make some of the puzzle fit together

IMG_1230 IMG_2460 IMG_2462

heat riser is Widget-approved
heat riser is Widget-approved

IMG_1239

fitting the barrel
fitting the barrel

 

exhaust manifold - where falling gases inside the barrel are channeled into the bench exhaust pipe run
exhaust manifold – where falling gases inside the barrel are channeled into the bench pipe run

although the heat riser was made of insulative fire brick, I realized it would be even better with more insulation - so I cut apart an old water heater and added it - later filling the space between it and the riser with perlite insulation mixed with clay slip.
although the heat riser was made of insulative fire brick, I realized it would be even better with more insulation – so I cut apart an old water heater and added it – later filling the space between it and the riser with perlite insulation mixed with clay slip.

 

heat riser insulation finished and capped off with clay
heat riser insulation finished and capped off with clay

IMG_1591

trench for thermal mass foundation/insulation layer
trench for thermal mass foundation/insulation layer

insulative firebricks and perlite to separate the thermal mass from the infinite heat sink of the earth
insulative firebricks and perlite to separate the thermal mass from the infinite heat sink of the earth

Forms for the thermal mass (they wound up bowing outward some between the internal supports, but not too badly and I like the organic wavy lines that resulted)
Forms for the thermal mass (they wound up bowing outward some between the internal supports, but not too badly and I like the organic wavy lines that resulted)

IMG_1755

And then winter came, and we hit the road, leaving the wet clay of the combustion chamber to slowly dry out over the wintertime.

When we returned in March, we got to work on the thermal mass bench … which turned out to be a lot more work than we’d bargained for.

laying out the exhaust ducting, and taping all the joints.
laying out the exhaust ducting, and taping all the joints.

 

Kristin did all the mixing. ALL of it. We mixed 2 parts sand for every 1 part of clay. We went through at least a full yard of sand (two trailer loads) and almost all of the free clay we'd scored. It took us several solid days to get it all mixed and added to the bench ... Kristin's feet and my hands looked like they'd been to war by the end.
Kristin did all the mixing. ALL of it. We mixed 2 parts sand for every 1 part of clay. We went through at least a full yard of sand (two trailer loads) and almost all of the free clay we’d scored. It took us several solid days to get it all mixed and added to the bench … Kristin’s feet and my hands looked like they’d been to war by the end.

 

Exhaust duct was coated in clay slip for maximum heat transference. We tried to use as much river rock as we could to save on clay and sand, but it still took an incredible amount to fill the bench (23' long, 14" high, and 24" wide - wider where the forms bowed out)
Exhaust duct was coated in clay slip for maximum heat transference. We tried to use as much river rock as we could to save on clay and sand, but it still took an incredible amount to fill the bench (23′ long, 14″ high, and 24″ wide – wider where the forms bowed out)

first test fire! It went .. OK. We decided to wait until we had more completed before really testing her out.
first test fire! It went .. OK. We decided to wait until we had more completed before really testing her out.

feeling the heat at the top of the riser
feeling the heat at the top of the riser

IMG_4014

slowly filling the forms with clay/sand mix and rocks. Kristin down at her mixing station.
slowly filling the forms with clay/sand mix and rocks. Kristin down at her mixing station.

ha ... so it got too hot for pants in the sunny greenhouse
ha … so it got too hot for pants in the sunny greenhouse

IMG_4024

Music was a required tool to help maintain spirits during the tedious mixing process.
Music was a required tool to help maintain spirits during the tedious mixing process.

IMG_4029

Kristin developed a technique of slicing off slabs of clay and spreading them out on the sand, then topping that with more sand, before starting to stomp and twist.
Kristin developed a technique of slicing off slabs of clay and spreading them out on the sand, then topping that with more sand, before starting to stomp and twist.

IMG_4628 IMG_4042

Finally getting to the top layer! The last foot or so seemed to take forever to fill in. (This is still sand/clay mix - but some of the clay was a white instead of red.)
Finally getting to the top layer! The last foot or so seemed to take forever to fill in. (This is still sand/clay mix – but some of the clay was a white instead of red.)

end of the bench before the exit to the chimney - was insulated with perlite/clay mix end cap
end of the bench before the exit to the chimney – was insulated with perlite/clay mix end cap

IMG_4671

Bench completed!! Now to start drying out several tons of wet clay ...
Bench almost completed .. just had to let it set up before removing thos internal braces, and filling in the gaps they left behind. Then it was time to start drying out several tons of wet clay …

IMG_4722

Chimney V1 - uninsulated and rather short. Initial burns couldnt even drive smoke up the pipe - it just pooped out onto the ground through the open cleanout hole at the bottom, because all the heat had ben leached out by the wet, cold clay bench.
Chimney V1 – uninsulated and rather short. Initial burns couldnt even drive smoke up the pipe – it just pooped out onto the ground through the open cleanout hole at the bottom, because all the heat had ben leached out by the wet, cold clay bench.

added some thermal mass to the barrel to limit amount of heat lost to radiation off the metal. Using the heat at the top for a wood drying rack. Artichokes enjoying the radiant heat.
added some thermal mass to the barrel to limit amount of heat lost to radiation off the metal. Using the heat at the top for a wood drying rack. Artichokes enjoying the radiant heat.

Chimney V2 - taller. (I don.t
Chimney V2 – taller. (There doesn’t seem to be a photo of Chimney V3 aka “Paul Baxter” – with insulation and a wind cap courtesy of a nameless donor.)

 

IMG_4820

Booster fire! This proved crucial during the bench-drying phase for a fast drafting system with hot, oxygen rich flame - the little fire would be pulled up the chimnet, creating suction on the rest of the system, pulling air through the fire in the combustion chamber. (Now that it is dried out, we only use this to start the system up, to avoid cold air plugging up the system)
Booster fire! This proved crucial during the bench-drying phase for a fast drafting system with hot, oxygen rich flame – the little fire would be pulled up the chimney, creating suction on the rest of the system, pulling air through the fire in the combustion chamber. (Now that it is dried out, we only use this to start the system up,  avoiding a cold air plug)

 

the wickets that support the row cover fabric are visible here (yard sign posts we scavenged)
the wickets that support the row cover fabric are visible here (yard sign posts we scavenged)

 

Before the chimney was upgraded further and before the thermal mass was fully dry – it was already working! Temperatures on the plant try bench stayed over 20 degrees warmer than outside, night after night – with no need to tend the fire after bedtime, and zero risk of the heat going out in the night – you can’t stop a warm giant rock from radiating! Plus it was warming the soil itself, and not just the air around the plants – great for happy, healthy root development.

IMG_4941 IMG_4828

IMG_5170
toasting bread for an experiment in making kvass

IMG_5166

reheating and crisping leftover pizza while firing the mass for the night
reheating and crisping leftover pizza while firing the mass for the night

added a blast furnace window to the aluminum pot I use as a lid (saved from a now demolished Ford assembly plant)
added a blast furnace window to the aluminum pot I use as a lid (saved from a now demolished Ford assembly plant)

IMG_4932 IMG_4936

It’s been a success. In recent nights just below 40 degrees, it kept the hot weather plants happily over 60 all night – maintaining the same 20+ degree heat increase seen at lower temps. It feels great to have it finally done, and really working wonderfully for our needs. It was a lot of work, but it was absolutely worth it. Plus, now we have experience in mass heater construction, so a mass heater in a future home is definitely a possibility …