Tag Archives: FECO

The Microbes Version of the Thermal Compost

March 13, 2020

The Essence of A Thermal Compost
as told by the microbes, in community

Material Variety

Amy Amoeba begins the compost story, “Wow. I just got thrown onto a big pile with critters I have never seen before.”

“Yes indeed”, echos Belinda Bacteria ecstatically, “Look at all the nitrogen choices: one bucket beer mash – very hot commodity, and three buckets of finely chopped fresh plants, coffee grounds and seeds. Yum. Yum.”

“As for me”, responded Henry (fungal) Hyphae, “I prefer the six buckets of carbon a la carte: sieved wood chips, hardwood bark and brown leaves. Plenty of carbon here for me to put away in the soil. I can break down lignin and even plastic!”

Belinda again. “I just got a text from my cousin Armando Bacteria. He’s in a pile with only manure and straw.

“Oh no!,” the microbes chanted, “Borrring. With so little diversity, that compost might not have enough nitrogen-metabolizing bacteria. And will it be the best pathogen suppressant?”

Sun, Mar 15, 2-4, Work Party
Mon, Mar 30, 6:30-8:30pm, Fig Pruning Class
Mon, Apr 6, 6-8pm, Work Party
Sun, Apr 19, 2-4, Work Party

The Mesophilic Stage

“It’s getting cozy now.” Pretina (predatory) Nematode was delighted. “At 125F, and with 50% moisture, we can feast without worrying about whether we’ll use up the oxygen or water.”

But Henry sounded the alarm. “Well let’s not spoil it Pretty Pretina. Let’s just keep the temperature right where it is. Slow down. Chew each bite 20 times.”

Amy Amoeba, transformed in her naked form, moved closer. “But wait Henry. We won’t get rid of those nasty plant pathogens until it feels like an oven in here.”

The Thermophilic Stage

“Whoa”, cried Nemar, the young bacterial-feeding nematode. “We have been pigging out, using the moisture and oxygen. We may end up in a dray sauna! I think I will lay an egg and then get outta here.”

“Belinda Bacteria choked out a few words. ” I am only so mobile and I can’t get to that bamboo pole with air holes in it. I’m writing my will.”

“Oh no you’re not,” exhorted Amy, “I insist that you encyst! If the temperature is above 131F, we only have to hang on for three days or, at 150F – just two days and, if we can handle 165F – just one day. Those times and temperatures will take care of the pathogens. Look over there. Silly Ciliate is spinning into a dormant cyst right now. Maybe we will get through this. It’s necessary that everybody take a turn in the hot center.”

“Well now”, slurred Baxter the nasty (pathogenic) bacteria. “150F this morning. Pretty hot but I found a completely dry pocket in some oversized chips. I can weather the storm tucked in here. Feng Farmer better do a thorough job of watering and turning if he wants to eliminate me and my weed seed pals.

“Oh my. What is going on?” Baxter’s adrenaline soared. “Someone just tossed me from the middle of the pile to the outside and the outside of the pile is going into the middle. And a splash of water everywhere. This farmer knows how to rid the compost of pathogens.”

“Oh. Yes. Feng is a pro!” Pretina confirmed, “I have been on this farm for years and I know they turn and water the pile. But they only turn as many times as needed to ensure all parts roast for the required amount of time, per Amy’s outline above.”

The Cooling Stage (Second Mesophilic Stage)

The alarm clock of Nemar’s protected egg sounded and he broke out from his dormant state. “Hello everyone.” He panned the abundant new microbial mix, searching nervously for any hyphae that might be constructing nematode-trapping loops. He twisted toward an unknown amoeba. “Can you tell me where the nearest Starbucks is? I just woke up.”

The amoeba responded kindly. “There may still be some remnants of the coffee grounds but most of us drink compost tea. It’s cheap.”

The young nematode sipped some tea and observed how fast the numbers and types of microbes were increasing. They were coming out of dormancy, hatching from eggs,  joining from the surrounding soil, or being dispersed by a larger organism. It seemed they were falling from the sky. So many different microbes! Tens of thousands per gram of soil. “Time to eat!”

The Maturation Stage

In six month’s time Nemar’s nematode egg grew to be a reproductive adult. She knew the compost had been stable enough for the garden for a couple of months; microbial respiration had slowed and the pile had reached ambient temperature. She also knew, however, that the diversity of the pile kept increasing for about six months and right now the compost was mature for one of its main uses – as a pathogen suppressant. The proof, of course, will be in the pudding: the successful seed germination and hearty plant growth.

“We are in the zone!” She shouted to the others. “The volume of fungal hyphae have finally caught up and we now have a fungal to bacteria ratio of 4:1, perfect for the apple trees. The color of our pile is dark brown and doesn’t smell like rotten eggs. I hope Feng is not thinking to wait until we look like soil because at that point, we won’t be compost anymore. Feng! Liberate us. Use us or lose us!”

“Feng is so smart. Here he comes with his wheelbarrow”, smiled the amoeba. “We can keep the soil food web going.  Those of you who aren’t coming along in this ride, you’ll be comfortable because Feng will maintain the pile at about 35% moisture.”

Feng looks closely into the pile. Belinda Bacteria has the energy and divides. But here comes the nematode to snarf up her new sister. A clever fungal hyphae squeezes Nemar’s offspring, and it’s not love. Then Amy Amoeba sits and sucks on the hyphae, but then soon becomes lunch for a Springtail (Collembola).

I acknowledge Dr. Elaine Ingham, with Soil Food Web, who makes science very accessible. And to Seattle’s Sound Bio Lab, a non-profit science lab that turns no one away.

The photos are from my microscope, sent to ClipppingPathIndia where they make line drawings from photos.

Watch the freewayestates.org calendar for a thermal compost class in May.

© 2020 Ruth Callard

Ten Years at Freeway Estates

February 18, 2020

Volunteers who put in 20+ hours last year gathered recently to sip Chestnut soup and brainstorm. Good ideas flowed, including a suggestion to add a sign to the kiosk, summarizing our efforts during the past ten years. Below is the content created by the 20-hour club.

Freeway Estates Community Orchard (FECO) is located on Duwamish land. Today this 12,000 square foot plot is managed by the Washington State Department of Transportation (WSDOT) and leased to FECO.

In 2010, a small group of neighbors planted the first fruit trees and began transitioning the grass and invasive plants to planting guilds. In 2013, the City of Seattle awarded us a Neighborhood Matching Fund grant (NMF) to formally survey the neighbors about their vision for this space. We were unanimous in choosing one concept and created our Vision and Mission Statement:

Vision: Seattle residents have nearby access to a beautiful public space where they can learn and participate in food growing, connect with neighbors, and nurture the environment.

Mission: We are creating an inclusive, action-oriented community, excited about:

–producing organic food to be shared,
–educating ourselves and our neighbors,
–improving and beautifying this public space.

In 2015 we received a large NMF grant and, guided by our steering committee, volunteers built infrastructure which included: gravel paths, a shed re-build, two rain-water cisterns, plumbing for city water, and raised beds. Another small NMF grant in 2018 allowed us to implement a water conservation project.

Sat, Mar 7, 10-12 Work Party
Sun Mar 15, 2-4, Work Party
Mon Mar 30, 6:30-8 Fig Pruning
Mon Apr 6, 6-8, Work Party

All of our NMF grants required volunteer matching hours. We have always exceeded the requirement. To date, more than 150 volunteers have logged a total of 11,000 hours.

We grow all of our food in compliance with organic standards. We produce our own thermal compost. We continue to learn about urban agriculture and share our knowledge with each other and with other organizations. We sponsor workshops on fruit-tree pruning, compost production, culinary herbs, invasive plants, and pollinators. We regularly host grade-school children. Since 2011, we have offered an annual cider-pressing festival for neighbors and friends.

One of our major ongoing activities is growing food for the University District Food Bank. In 2019, from just four garden beds, we contributed more than 700 pounds of fresh produce for neighbors in need.

We have faced many setbacks in terms of theft and vandalism. It is challenging to work in such a public location. However, when a neighbor walks through and expresses appreciation and gratitude for what we are doing, we feel the rewards outweigh the disappointments.

For the near future, we are increasing our commitment to use resources wisely and to include all people.

FECO is a hub where neighbors and volunteers connect. We welcome everyone. No special skills are needed and we have tasks for all levels of ability.

Contact us at freewayestatescommunityorchard@gmail.com.
Support us at FreewayEstates.org

The 2019 20-hour club: Maxwell, Joan, Reid, Kate, Jennifer, Sue, Nancy, Allison, Michelle, Amy, Nora, Ruth, Arly and Brannon

Pathogen-Reducing Compost

January 14, 2020
© 2020

Benefits of compost are widely known: 1) enhances water holding capacity, soil structure, organic matter, drainage, and nutrient holding capacity of soil, 2) provides a source of beneficial microbes, 3) decreases both inputs (to your garden) and outputs (from your garden), a plus for sustainability, and, 4) reduces fertilizer and pesticide use.

However, did you know that well-made compost has the ability to reduce pathogens and enhance plant growth?

An extensive research study of 120 bioassays, involving 18 composts and seven pathogens, found positive disease suppression in 54 percent of the treatment combinations, a disease stimulating effect only rarely (3%), and no effect in 43 percent of the treatment combinations (Termorshuizen et al., 2006).

Other studies have shown that “backyard” compost is superior to the commercial product, possibly due largely to richer and varied starting materials, plus a more relaxed thermophillic phase (wherein temperatures are sanitizing but lower than those recorded in commercial composts). Backyard composting presented higher counts of bacteria, actinomycetes, and fungi. It also shows higher percentages of isolates producing extracellular enzymes which allow the breakdown of tough substrates, including polyethylene!

Although the studies show the efficacy of compost, no one has come up with the perfect recipe or management strategy to combat a particular soil pathogen. This is because the soil microbial community is so dynamic and complex. Quality control tools are also lacking.

Still, we know from research that microbial organisms in compost are able to reduce pathogens my means of: direct antagonism (antibiotic production and direct parasitism), predation, competition for resources, enzyme production, and, induced resistance in plants – through signaling networks and hormones.

Sun, Jan 19, 2-4. work party
Sat, Feb 1, 10-12, Work Party
Sat, Feb 1, 1-3, PRUNING CLASS
Sun, Feb 16, 2-4, Work Party
Sat, Mar 7, 10-12, work party

Note, compost is more effective as a pathogen prevention method than when used as a management strategy for some existing soil or plant pathogen. Elaine Ingham, veteran soil scientist, points out that compost and soil should be colonized with a sizeable and diverse body of microbes. “There are only so many seats at the table. If the good guys are already there, the bad guys are turned away.”

Image Credit: Zosia Rostomian & Jill Banfield, Creative Services, Berkeley Lab

Who are these microbial actors who play such a beneficial role in a garden? It’s bacteria, fungi, protozoa, and nematodes, none of which can be seen with the naked eye. There are millions of microbes in a gram of compost and hundreds of thousands different species. In fact, it’s the diversity of players that makes good compost a pathogen suppressor.

Commercial composts can differ widely in their suppressive effects and can vary as to which pathogens are diminished. However, commercial composts can meet the objective of adding organic matter to the soil. In contrast, the special compost that you can produce with backyard composting, using correct temperature, moisture, aeration and curing processes, will yield a compost that you can use sparingly as an inoculum throughout your garden. It will jump-start good soil biology and maintain nutrient cycling, creating an environment fostering pathogen-suppressive soil.

Next up – A template on making a thermal compost.
Also, watch the FreewayEstates.org calendar for a hands-on thermal composting class, coming in early May, 2020

Ruth

References:

Hadar & Papadopoulou, 2012 – Suppressive Composts: Microbial Ecology Links Between Abiotic Environments and Healthy Plants DOI: 10.1146/annurev-phyto-081211-172914

Vaz Moreira et al., 2008 – Diversity of Bacterial Isolates from Commercial and Homemade Composts. DOI: 10.1007/s00248-007-9314-2

Welgarz et al., 2018 – Microbial diversity and nitrogen-metabolizing gene abundance in backyard food waste composting systems DOI: 10.1111/jam.13945

Fayolle , L., 2006 –  Eradication of Plasmodiophora brassicae during composting of wastes
https://bsppjournals.onlinelibrary.wiley.com/doi/full/10.1111/

Cangelos, G, 2014, Dead or Alive: Molecular Assessment of Microbial Viability
https://aem.asm.org/content/80/19/5884 DOI: 10.1128/AEM.01763-14