A Risk Injury Table that accompanies each compost report, will guide growers in avoiding potentially risk applications

Composters face certain risks when growers purchase and use products for which herbicide residue effects have not been properly evaluated. The situation has propelled Woods End Labs to upgrade its auxin-injury plant test by adding Risk Categories.  The goal is to hybridize plant-injury ranks with compost application rates.  “People are being misled into believing that once you have a herbicide residue, the compost is no good,- this is simply not true” says Brinton.  The new protocol is based on Woods End’s Compost Matrix, a quality certification system developed for composters that “enables skillful placement into best-use categories” – or, in the case of residues “helps avoid exposing a market segment to undue risk”.  Matrix arrays are mathematical devices to sort complex data into simple groups, and appear to work well with plant-injury symptom ranks.

Upgrading the herbicide bioassay to add risk evaluation involved creating plant subcategories: sensitive, affected, and insensitive. It also requires calibrated injury rankings from real bioassays.  Wood End first developed the test in 2005 and published several journal articles, including one in Compost Science Utilization (2006- Vol 14:4) , which discussed how bio-assays may be confounded by other anti-quality factors in compost, such as salinity and boron, that interfere with herbicide bioassays. The boron toxicity research was also published in CSU in 2008 (Vol 16:2) since boron caused similar injury in beans that herbicides can. Brinton’s new research will go into a future paper showing the PIRM system working for 4 different auxinic herbicides.

PIRM will show compost application rate thresholds, also called No-Effect Levels (NOELs)  that avoid expressing injury symptoms. “In some cases the injury can’t be avoided, so no application rate is considered appropriate”.  Brinton reports that several compost companies (PA, UT, VT, ME) are presently using the risk management tool and some have successfully piloted their compost products “out of harm’s way”. Woods End also has developed a means to screen raw source-ingredients before they are even put into composts.  “The goal is to move compost and growers from a high-risk to a low-risk category by careful management guided by our matrix bioassays”.

Fine Plastic fragments in compost (top) and floating plastic found 2012 in Lake Michigan

A frothy storm has been brewing recently as home consumer products are discovered that have micro-bead plastic content designed to give a “lift”. The problem is: they are real downers for aquatic life. A day after the Dec 28 2012 news that Lake Michigan is being clogged with plastic contamination, Unilever announced it will be withdrawing plastic micro-beads from home products like soaps and shampoos, due to “some evidence that they are harmful in oceans” (Editor: the scientific evidence that microplastics are damaging oceans is overwhelming). While many consumers are reacting such as: “I didn’t know there were plastic beads in my shampoo…”  others are demanding faster action on microbeads than proposed by Unilevers 2015 target. “Exfoliating” plastic ingredients are found in other big-brand products (such as Olay, Dove and others). These products share in common the presence of tiny particles of polyethylene intended to help lift dirt from your face: it all then goes down the drain into waste-water, where it is considered too small to be recovered. Some waste-water plants are reacting with information about the fate of micro-beads in their process while others are determining if any are present in measurable amounts at all.

1) Our waste arrives 2) a sorting glass from paper 3) newsprint floats off 4) HDPE2 segregated 5) colored paper is baled and 6) HDPE is baled

The surge in single-stream recycling in the Northeast is reminiscent of the early 90′s, when “dirty MRF’s” were a stand-in for source separation and clean composting. Since then, many communities have struggled successfully to establish participation in “source-separation” or multiple-stream programs,- but  recycle rates are still low. Switching to a single-stream system is to some either a luxury (being so simple) or craziness (mixing what was once separate). In early MRF history, food and trash were comingled with recyclables. These are now separate but there is a need for additional segregation for composting or energy (biogas) recovery of organics.  While statistically the recycle rate increases significantly with single-stream programs, the trade-off is alleged to be a reduction in quality. Supposedly, glass shards, plastic and micro-foil fragments are tumbled into processed paper and cardboard fibers, increasing the chance they will not meet market standards. “The problem with a single-stream program is that it renders most of the commodities recycled practically worthless,” says Don Casavant, chairman of Auburn Maine’s Solid Waste Subcommittee.  But the last 10-years history at Portland, Maine’s recovery facility speaks otherwise: all products are being sold, and recycle markets are adjusting to single-stream quality.  A 2013 feasibility study for recovering the compostable fraction is underway for Portland’s facility. As 20 years have gone by since we started sorting waste, the general feeling now is that this new single-sort system “has got to work”. Still, single-sort does not appear to be a money-making business, and communties sharing costs are just opting for something better – but more expensive – than landfilling. //

Two bubble domes that also store methane cover these mesophilic dairy digesters producing 1MW per year, supplemented with 25%vol food waste.

According to the US Biogas Council, there are 181 farm-based biogas producers in America. That’s as many as in, perhaps, one county in Germany. But no matter. The difference between biogas- the dark horse- and “sexy” solar and wind that everyone is talking about in America, is that biogas is STEADY and STORABLE. The others are not (without huge costs). That’s a huge advantage to biogas- methane. Methane production is literally modeled after nature’s biology, and is a highly non-technical energy source ( a cow’s stomach) – to its credit. Our story is about Maine which up until recently  has been very quiet on the farm biogas front. Maine ranks 43rd as energy producer, yet half its net electricity generation comes from renewable energy: 25% hydro, 21% wood, and 4.5 percent from wind (solar is the next fastest growing source and Woods End will soon be a net electricity solar-fueled laboratory).  Back to our story. Now, the new blip on the radar is the Fogler Family 1,200-cow farm, which recently opened a 1MW digester  (Danish and Spanish design). “Looking at it you feel like you are in Europe” — said Brinton who with a group of dairy farmers toured the facility in Exeter. The dual-source system utilizes manure slurry (75%) augmented with food wastes (25%) in a mesophilic, stirred system. At 1 MW yield, the digester is larger than most in the Northeast, and larger than typical farm digesters in Germany averaging 280kW (Baveria statistics).  This new system does depend substanitally on industrial food inputs on top of manure for half its energy yield.  That’s because manure overall ranks nearly lowest and food-scraps possibly highest for net methane , so combining them makes a lot of sense. Still, farmers question becoming permited solid-waste facilities to get the extra (often salty) punch from food waste.  Woods End operates a full-scale biogas test lab helping waste producers gauge methane potential and digestate fertilizer quality.

Damaged - and recovered - tomato plants.

Tomato seedlings were severely damaged (see inset) by manure compost used in Will Brinton’s family garden. The compost came from a Pennsylvania facility. “We thought the plants would not survive” said Brinton, who prepared potting-mix with the compost. In his work at Woods End Labs Brinton has researched compost contamination resulting from “carry-over” of farm chemicals. Woods End has published a red clover bioassay method to detect potential toxicity. “We  failed to check this compost, as it came from a colleague composter.”  However, what appeared to be severe damage was short-lived. By transplanting the affected tomatoes into clean garden soil, the plants recovered fully and have gone on to produce healthy vigourous growth (see image). “It took about 2 – 3 weeks to completely overcome the seeming harsh effects”.

Similar reports have surfaced in Maine and Vermont with  damage traits to tomatoes as twisted leaves. “It’s caused mostly by picloram, a pasture-range herbicide which horse farms are using to control troublesome weeds like thistles and milkweed in their pastures”. The label for these herbicides specifically does not permit exporting manure or grass from such farms to be used either for growing plants or for composting. “Never the less, horse manure is popular and so these farms are allowing growers and composters to take the manure for their personal and composting uses.”  Woods End Labs, which tests compost from all over the hemisphere,  believes there is a better way. “Ideally, there would be oversight and stricter control of the label”. This would mean that farmers who use the products must agree that the manure (and hay) from treated areas is not available for composting or subsequent soil treatment.  Brinton stresses the good news as far as growers and compost customers are concerned: even severely affected plants can recover from damage if they are removed from the contaminated  growing media. “Tomatoes are vigorous plants and will survive rough transplanting.”

Woods End labs tested an unused bag of 10-year-old compost, stored moist since 2002 in our greenhouse. In this case, it was from Land & Sea Compost (the company is no longer in business but was featured in a Biocycle August 1996 article). Chris Smith, the composter, combined regional leaf and yard waste with small amounts of fish by-products to make his premium garden blend.

Results of testing this 10-year old product are as follows:

The product is definitely not only not worn-out as some might expect, but is in near perfect (premium) condition… still. What was also interesting were the bacteria/fungi counts observed from culturing the product:

Total aerobic count: 7.3(Log10 cfu/g) – that’s 2 x 10⁷
Filamentous Fungi : 6.1 (Log10 cfu/g)
Thermophilic Bac. : 6.6 (Log10 cfu/g)

This aged product had a respiration rate 2.5-times higher than normal fertile soil and bacteria counts typical of very fertile soil. We also found residual evidence of early high-heat composting in the elevated thermophilic spore counts. Cress growth was better than found with most younger composts and nitrification (conversion of ammonium to nitrate) was optimal. The material is – well, ideal compost, premium for soil use … 10 years or more after it was made. Growers who find a compost they like should consider buying a stock of it and storing it covered (but moist) and using it year after year, instead of having to buy fresh,- and probably immature – product each season. Cure on!

30 years ago ... a soil test survey by Dr. Liebhardt rocked soil labs nationwide .. and still is exerting an influence ... for the good.

It has been exactly 30 years this spring since Dr. William Liebhardt and colleagues published a carefully crafted survey of 69 USA soil test labs. In the ensuing uproar, some suggested Bill Liebhardt had thrown his career away. Recollecting the events, Bill (retired Ag Scientist, UC Davis CA) told us: “At agronomy meetings where we presented the results, there was standing room only left and out into the halls.” Woods End Labs was one of the 69 commercial labs that received blindly 5 farmer soils, with listed crop histories, and a request for recommendations to grow 125-bu corn. Woods End determined several of the soils were very fertile and required little added fertilizer, but the majority of surveyed labs did not agree.

The problem Liebhardt uncovered was not so much the soil testing per se, although there were disturbing differences such as in measuring soil organic content. The stinging issue was the way labs used (or did not use) test results to construct fertilizer recommendations. And the big one was, then as now, nitrogen. Only 15 labs adjusted N-prescriptions to apparent soil potential and only 3 labs, ours included, pin-pointed the high N-potential soils (rich humus and prior alfalfa in the rotation).

There have been many advances and improvements in soil testing since this time, yet nitrogen remains a challenge. The storehouse of potentially available N is the soil organic matter fraction which has been traditonally overlooked.  Our 1982 soil reports showed some of Liebhardt’s PA soils were richly supplied at 4 – 5%OM. Natural biological release could be counted on to provide a significant contribution. Considering this, for most of the labs, the fertilizer N rates appeared excessive. This burning theme casts a long shadow: a very recent CA study suggests that excess nitrogen fertilizer is straining the state’s ability to deliver quality water.

The fact the majority of soil labs in 1982 did not account for soil’s intrinsic nitrogen potential is not surprising as methods to measure biological response were uncommon, leaving labs to either make potentially inaccurate calculations – or do nothing.  Today, a combination of tools is available (plus soil proficiency programs to monitor testing) all of which may reduce the potential for excessive (and costly) fertilizer, yet the problem of labs not using any tests or tools other than crop requirements persists. Woods End’s Solvita CO2-Burst protocol is one newer means that did not exist earlier and which directly measures microbiological carbon turnover, the kingpin in potential N-release. Accounting for soluble N and adapting local soil and climatic factors will help make the new “soil health” approach a big step forward.   (Copies of the original study and Woods End reports are available by request: lab@woodsend.org). Download references documents HERE

In a first-time feat, composting of a Chip Bag was filmed in time-lapse for 14 weeks, and became a national TV ad. The bag was eventually withdrawn from the market.

The day before Earth Day 2009, fans of American Idol were wowed by a TV ad showing a SunChips bag disappearing and turning into compost, right before their eyes. The ad was genuine. It took stitching together 8,800 individual images shot within a see-through compost chamber, designed and built at Woods End Labs. Frito-Lay declared “the World’s first Compostable Chip Bag,” with full release promised by Earth Day 2010, ushering in — it seemed — an exciting new era for compostable consumer packaging.

Today, store shelves are conspicuously absent of the product — or  just about anything like it.

News buzz in the sustainable packaging industry may partly explain the double act of disappearance. British giant Innovia Films Ltd (IFL), in multiple legal actions filed in the United Kingdom and the European Patents Office, has charged that Frito-Lay’s innovations are the rightful property of IFL. Innovia has successfully petitioned Brussels to block one of Frito’s European patents on the bag, and has pressed for free license rights to Frito’s technologies. (IFL has launched its own version of the compostable chip bag, using metallized cellulose instead of PLA.  ASTM D6400 tests have shown both types of products break down in the same time-frame.)

Even more recently, Frito-Lay has filed a complaint for Declaratory Relief against Innovia, asserting original invention rights. Sustainable packaging advocates are clearly watching the outcome. We are not in a position to comment on the legal merits of the cases. One thing is clear, Frito-Lay was first in the chip marketplace with an authentic PLA-based compostable product.

Postscript: Woods End continues to work with many firms testing and characterizing the unique environmental traits of bioplastics. Yet, interest in compostable films appears to be shifting to higher ground … reusability and carbon footprint. (Research for this article based in part on GreenPatentBlog.com, Foodnavigator-usa.com, Sustainable Packaging Forum, and FoodProductionDaily.com /ps/wfb)

A close relationship of 24hr soil CO2 pulse and nitrogen release by another method: makes soil biology appear more relevant and practical.

Woods End and its partner,  the USDA-ARS soil lab in Temple, Texas have been running comparison of soil respiration and nitrogen mineralization using a number of traditional methods. One test called 7day N-min, has shown surprisingly good correlations to the rapid CO2-burst method that Solvita and USDA have developed (see figure). The 7-day N-min measures microbial activity and nutrient-release in an indirect, time-consuming process, and labs are hesitant to use it, or if they do, they have to charge more than farmers may be willing to pay. “Yet the information is vital to understanding how to save costly nitrogen fertilizer- without loosing any yields – plus it shows you something important about soil biological health”- Brinton of Woods End states, who invented the test in 1996, but has seen this many years go by in realizing the application.

PARTNERSHIP: The new soil Solvita CO2-burst protocol is a unique collaboration of Government and Private Lab: Woods End Laboratories and Dr. Haney’s USDA-ARS soil lab in Temple, TX, both centers that had been pursuing soil quality for 25 years. The new protocol puts the measurement of soil microbial activity into the realm of the practical and is cost-effective for commercial soil labs to perform.

WHY TEST SOIL MICROBES: The quantity of active soil microbes – fungi and bacteria- can be represented by actual living carbon associated with “respiring (live) cells producing CO2 within a soil systems” – from Dr Haney and Brinton. This living microbial consortia is associated with many positive properties such as transforming chemicals, aiding pesticide degradation, facilitating the release of nitrogen from organic matter and contributing to soil aggregation. The latter property alone may account for more than 50% of soils ability to resist erosion.

RELEASE of “FREE” NITROGEN: Measuring microbial activity is not the same as determining total organic matter (SOM) or  total-C, and then estimating the potential release of nitrogen – a method which some labs have relied upon, but which can give remakably inaccurate results. 7d N-min will actually measure the nutrient release but under harsh circumstances of 40°C anaerobic incubation. Other tests the team has used are direct 28-day mineralization of nitrate and ammonium, showing similarly good correlations. Added to the roster are crop uptake studies which are showing that the amount of nitrogen present in unfertilized crops- called “controls” – closely corresponds to the amount predicted by the soil biology test. “There is a great deal of interest in showing how this biological function behaves in different growing regions” says Brinton.

Popularly called "Biochar", Europeans suggest re-naming to "Plant Charcoal" - A 2009 study shows even with massive mobilizing of 10% of all biomass to biochar only 1.6% of Germany's carbon footprint would be offset."Is it even worth the effort?"

The re-discovery of “Terra Preta” in the Amazon Basin marked for soil scientists a possible turning point: the idea that an ancient practice could provide insight into correcting CO2 build-up and staving soil decline.  “Millions of Euros have been spent now on biochar studies”: conference organizer for the Berlin October 2011 ANS-Symposium intoned.  Far from the near-panacea biochar in USA presents for saving climate and soil, the European lab tests along with tough EC climate regulatory debate  ”cast doubt that significant progress will be made until many questions are answered”. The Institut für Agrarrelevante Klimaforschung presented data showing variable carbon-stability and summarized  soil-plant studies confirming that negative effects are almost as common as positive effects. The big topic was lab tests which suggest biochar carbon has as little as 35% stability or possibly “climatologically irrelevant”. Editor Dr. Kehres (Journal “Humus and Agriculture“) summed up the symposium: “Biochar appears over-rated … the biochar claim to 1,000 yr stability is revised downwards to 10-100 years, roughly the same as compost”.  Details on the fractions of carbon from pyrolysis, HTC and other carbonizing  methods weighed against the lack of  method standards, plus rankling over carbon legislative validation,  suggest a biochar future “if even economical”  faces many hurdles. The symposium eventually turned to name calling: it was proposed to drop the prefix “bio” from biochar, a “technical misnomer” – and a source of confusion in Europe where “bio” means certified natural farming. What’s the name to be?- “Plant Charcoal”- (“Pflanzenkohle – its more accurate”).