Category → Agriculture
[With a note on some confusion about wheat, and if it has been genetically modified (see below)]
The herbicide 2,4 D is pretty powerful stuff. It has recently been in the news because it kills weeds that have developed resistance to glyphosate (brand name Roundup). In May, I wrote about efforts by Dow AgroSciences to bring a new genetically modified corn to market that has been engineered to be tolerant to 2,4 D.
The idea is that the new corn would withstand applications of both glyphosate and 2,4 D, and that farmers would use those two herbicides, and presumably a rotation of at least one other chemical control, to kill weeds and prevent new occurrences of resistant weeds.
Along with the new corn, Dow scientists created a new version of 2,4 D, called 2,4 D Choline, that is less likely to drift off the fields where it has been applied. Now, one group of growers, the Save Our Crops Coalition, has issued a joint statement with Dow saying that the information Dow has supplied about reduced drift and volatility, along with the company’s pledge to investigate non-target claims, has gone a long way to satisfy its concerns about migrating herbicide. Both SOCC and Dow say they have “agreed to modify positions with respect to pending regulatory matters around 2,4-D tolerant crops.”
Prior to this agreement, the Save Our Crops Coalition had used the USDA’s open comment period to request an environmental impact statement to assess the likelihood of drift from 2,4 D applications.
They pointed out that since not all farmers will be growing 2,4 D tolerant crops, drift to non-intended targets could result in significant crop damage, since it would be applied during the growing season (imaging a field of vegetables that got smogged by 2,4 D – the plants would croak along with the weeds).
I reported on Dow’s work to reduce migration of 2,4 D in the C&EN feature story. Here’s the relevant background:
David E. Hillger, an application technology specialist at Dow AgroSciences, explains that rather than traditional ester or amine forms of the molecule, which can volatilize in the environment, the new version is a more stable quaternary ammonium salt.
In addition, Hillger says Dow’s proprietary manufacturing process produces a product with less particle drift when application directions are followed. Dow recently reported that field tests of the formula showed a 92% reduction in volatility and a 90% reduction in drift.
Crops that contain the 2,4-D tolerance- trait will also tolerate older versions of 2,4-D. However, Dow has developed a stewardship program that obligates farmers to use a premixed combination of 2,4-D choline and glyphosate. The program includes farmer education about using multiple herbicide modes of action, the requirement to use Dow’s new herbicide mixture, and labeling instructions for proper application. State pesticide regulations generally require farmers to follow labeling guidelines when using herbicides.
For now DowAgrosciences is waiting on regulatory authorizations for 2,4-D tolerant corn, but the company says it plans to get the green light in time for the 2013 growing season.
Certainly there are other criticisms of the 2,4 D-tolerant crops still out there. One important concern is that farmers may use chemical fertilizers in such a way as to promote even more herbicide-resistant weeds – ones that cannot be killed with 2,4 D or glyphosate. Another is the possibility that the amount of 2,4 D used on crops will dramatically increase (glyphosate, though used in large amounts, breaks down rather quickly in soil).
And of course, foes of all types of GMO crops abound, and anyone who is against Roundup Ready corn is not likely to be in favor of the new varieties.
Speaking of which, I’ve noted a number of commentaries relating to wheat lately, apparently due to the rise of anti-gluten eating. Many leave the reader with the impression that the U.S. is awash in genetically modified wheat. This is incorrect – there are many wheat hybrids on the market today, but none have been genetically engineered.
I find it handy to refer to an online USDA list – updated seemingly daily – which lists pending GM crops as well as those that have been approved already (in the section titled Determinations of Nonregulated Status). You may want to bookmark it, or have it printed on handy cards to give to people.
This week’s issue of C&EN includes some news from algae-based biofuels firm Sapphire Energy. The company is reporting its first harvests of algae biomass from a large, outdoor algae farm in New Mexico.
Sapphire has grown and gathered 21 million gallons of algae biomass totaling 81 tons. Eventually, the plan is to make a kind of crude oil from the algae. They grow the stuff in very large outdoor ponds. According to the press release, “the cultivation area consists of some of the largest algae ponds ever built with groupings of 1.1 acre and 2.2 acre ponds which are 1/8 of a mile long.”
You’d think that the promoters of algae for biofuels would be clinking glasses filled with spirulina-enhanced juice at the news. But you’d be wrong.
In fact, a trade group of algae firms calling itself the National Algae Association says the kind of ponds used by Sapphire – known as raceway ponds (you can see why looking at this image) – will not scale up commercially. Instead the NAA supports the development of photobioreactors (PBRs for short). Similarly, algae researcher Jonathan Trent, writing in a New Scientist magazine piece that also appears in Slate is arguing in favor of photobioreactors. Specifically, Trent says PBRs should be deployed offshore. I’ll quote from his article where he summarizes the raceway/PBR tradeoffs:
There remains the question of how and where to grow the algae. A few species are cultivated commercially on a small scale, in shallow channels called raceways or in enclosures called photobioreactors (PBRs). Raceways are relatively inexpensive, but need flat land, have lower yields than PBRs and problems with contamination and water loss from evaporation. PBRs have no problems with contamination or evaporation, but algae need light, and where there is light, there is heat: A sealed PBR will cook, rather than grow, algae. And mixing, circulating, and cleaning problems send costs sky high.
Trent doesn’t mention what industry analysts complain about the most. When it comes to algae, though PBRs might be the best bet, they require too much capital expenditure for the equipment.
Meanwhile, Solazyme, which started life as an algal fuels firm but now is manufacturing oils for use in skin cream and other high value applications, grows its algae in a third way – its algae live in bioreactors, but in the dark. They eat sugar and make oil. Is there a best way to commercialize algae for fuels and chemicals? Is there any way? It seems that it is still too early to tell.
Sometimes when you dig a little on Google News you find fascinating nuggets in local news of the topics that we cover here at C&EN. A great example is in Knoxville’s alternative newsweekly Metro Pulse.*
Newshound Joe Sullivan digs into what ever became of $70 million that the state of Tennessee spent in the flush days of 2007 to start up a switchgrass and cellulosic ethanol industry in the state.
The good news on the project is that the promised 250,000 gal per year cellulosic ethanol plant did open, in Vonore, Tennessee. The bad news is that it has not been using any of the switchgrass grown on 5,000 surrounding acres. The switchgrass part of the project involved the University of Tennessee Institute of Agriculture. The state figured switchgrass would grow great there. And it seems to have been correct.
Sullivan reports that more than half of the $70 million project money went to build the pilot plant. But corporate partner DuPont (now DuPont Cellulosic Ethanol) has used the pilot plant to test and demonstrate its ability to make ethanol from corn stover. Corn stover is a feedstock that is available in huge quantities…. in Iowa. As it happens, DuPont’s first commercial-scale cellulosic ethanol plant is in Nevada, Iowa, and is set to come online soon.
C&EN has mentioned the Vonore plant a half dozen times (including in a previous post on this blog). The move away from switchgrass escaped our attention, but it is an important development for the UT folks and the farmers they have been working with.
So what will happen to the 50,000 tons of switchgrass that were harvested by Vonore-area farmers? Read the story to find out.
* Edited 8/28 to correct reference to Metro Pulse
It’s been a very busy summer, but I had a chance to catch up with Rick Eno, the CEO of Metabolix, last week. Metabolix makes a bio-based plastic that it calls Mirel, though chemists call it a polyhydroxyalkanoate polymer (PHA). We last heard from Metabolix in January when its commercial-scale partnership with Archer Daniels Midland dissolved.
The breakup was a significant blow to the company in terms of growing its business and selling Mirel to customers. The partnership with ADM was based around an ADM-financed production plant capable of making 50,000 tons of Mirel per year. Unfortunately, sales ramped up slowly and ADM said the market was too risky.
Since the breakup, Metabolix has decided to launch the biodegradable Mirel bioplastic under its own nameplate, says Eno. It has transferred inventory from ADM, and brought over all the business operations. Still, the company needs a production partner.
“Since Mirel was exclusive to ADM for so long, [after the breakup] we did get inbound calls and we also reached out to potential partners to establish potential manufacturing,” Eno told C&EN. He says that rather than try to sell enough Mirel to keep a huge plant busy, he’s now looking for something closer to a 10,000 ton per year scale.
“We’ve narrowed down a large number of potential opportunities to four. Now we’re looking at engineering detail for integration of our manufacturing technology to the partners’ asset sets,” Eno reports. “We’re deeply evaluating a short list of manufacturing options.” Without ADM to center the business, Metabolix can look outside the U.S. – for example, to be closer to customers. In fact, the firm has opened a sales office in Cologne, Germany to be close to the European market.
As Alex Tullo wrote in his recent cover story on biodegradable plastics, an important market niche is in organic waste handling – specifically in municipalities where organic waste is separated and hauled to composting facilities. Eno suggests this is both a good niche for PHA, and also a great reason to be in Europe where people rigorously sort their trash.
Eno followed up on his January comments that the company would look to higher-value markets that really require biodegradability, rather than try to compete with cheap and plentiful petro-based plastics. He said the company is focusing on agriculture and horticultural markets – for things like biodegradable plastic mulch; the consumer market for compostable bags and similar products for organic waste diversion; a broader packaging market; and a marine and aquatic segment where it is important that plastics biodegrade fully in oceans and streams.
The breakup with ADM somewhat ironically boosted Metabolix’s cash position (for some rather complicated accounting reasons). That will be a big help, because the company is still developing its upcoming portfolio of bio-based C3 and C4 chemicals, using different PHA molecules than Mirel uses as an intermediate. Example target chemicals are gamma butyrolactone and acrylic acid. The C4 program is the farthest along and has reached 60,000 liter fermenters in scale-up. Eno says the chemicals program has netted “significant partner interest.”
Also helping to pay the bills is a government grant backing the company’s efforts to put the bio-based plastic platform into purpose-grown plants. In a recent advance, Metabolix and its research partners have reported a new way to increase polyhydroxybutyrate (PHB) production in sugar cane.
So there you have it – Metabolix is still moving along. The next time we will hear from them, Eno says, it will be because they have a new production partnership to announce. Stay tuned.
French Agriculture Minister Stephane Le Foll said on Friday that the country plans to ban the use of a neonicotinoid pesticide used as a seed coating for the oil crop rapeseed, over concerns of its sub-lethal effects on honey bees, Reuters reports.
The Le Foll said his agency had investigated results reported in Science (see C&EN’s coverage by Lisa Wilson) that suggested bee behavoir was altered when bees were exposed to neonicotinoids as they foraged for nectar. Results from that research and others reviewed by the French agency for food, environmental and occupational safety showed sub-lethal effects that caused bees to not return to the hive, a behavoir that could weaken bee colonies. The agency issued a release about its findings – in English – which you can read here.
As a result, France now plans to withdraw the permit for Syngenta’s Cruiser OSR pesticide, when used as a seed coating for rapeseed. Cruiser includes one type of neonicotinoid called thiamethoxam. The rapeseed flower produces nectar that is harvested by honey bees. It is one route of exposure that recent research has investigated.
As C&EN and the Cleantech Chemistry blog have reported, research on possible causes for widespread collapse of honey bees – both in the U.S. and Europe – is ongoing. Neonicotinoid pesticides have been a focus of some of the research, as have parasites, viruses, and various modern agricultural practices such as monocultures.
The move by France has brought responses from the EU, Syngenta, and the European Crop Protection Association. These groups acknowledge that research shows that bees are negatively affected by neonicotinoids but they say the manner of exposure and the likely amount of exposure is likely much lower than what has been tested. Meanwhile, France has asked the EU to add tests for sub-lethal impacts on bees to its protocol for approving the use of pesticides.
Today’s post is from guest blogger Melissae Fellet, a science writer based in Santa Cruz, California, and was written for the “Our Favorite Toxic Chemicals” blog carnival hosted by Sciencegeist.
Feeding my vegetable garden so it will feed me
I’m eager to grow some of my own food this summer, so I planted a vegetable garden in pots on my porch. Since my previous gardening experience consists of ignoring my plants, learning some gardening tips was a must.
Like humans, plants need food, too. Those nutrients come from boosts of nitrogen, phosphorus and potassium-containing fertilizer. But plants need help getting their roots on some nutritious nitrogen when that fertilizer contains kelp, alfalfa, crushed bones, chicken poop and ground feathers, like the organic stuff I put in my garden.
Some of those ingredients contain nitrogen as ammonia, which plants can absorb directly. Proteins are another source of nitrogen. Bacteria in the soil separate proteins into amino acids. Other microbes chomp the nitrogen off the amino acids as ammonia. And super-specialized bacteria eat ammonia and release the nitrogen as nitrate (NO3-). Nitrate is great plant food, too, because it zips through the soil straight to a plant’s roots.
This biological nitrogen transformation is slow, so farmers may feed their plants a nitrate-containing fertilizer to speed growth. That’s a touchy subject in the agricultural areas near my home in California.
About 10 percent of 2500 public water wells tested in the Tulare Valley and Salinas Valley exceed the state limits of 45 mg nitrate per liter of water, according to a report prepared for the state water department last March. The majority of the nitrate in groundwater — about 96% — washes off cropland, the report found.
Nitrate takes time to trickle from a field into the groundwater, so most of that contamination is due to decades of past farming in the area. But if the nutrient pollution trend continues, 80% of the people living in those valleys could be drinking nitrate-laden water by 2050.
Nitrate becomes harmful when our bodies convert it to its chemical cousin, nitrite (NO2-). Nitrite transforms the iron in our blood so that it can no longer carry oxygen. Enough altered iron — 10 percent of the hemoglobin in your blood — causes breathing troubles especially in infants and pregnant women. Higher concentrations can lead to suffocation.
Still, it takes a lot of nitrate to harm a person. According to data from the World Health Organization [PDF], an average three-month old baby boy might have to drink about four liters of water contaminated with nitrate at twice the state limit to induce toxicity. An adult might drink up to 56 liters of the same water at once to get a fatal dose of nitrate.
Excess nitrate can be toxic to the environment, too. The nutrient washes into a Central Coast wetland, feeding microscopic algae until they grow into thick green mats that suffocate ponds and channels.
The UC Davis report says that fertilizer fees and improved groundwater monitoring can help protect drinking water. And policy changes are in the works for one part of the state. In March, the Central Coast Regional Water Control Board passed regulations to reduce nitrate-containing runoff from fields. These rules took three years to negotiate and they are still tangled in a lawsuit from growers.
Even without regulations, farmers can prevent nitrogen pollution by controlling the amount of fertilizer on the fields and feeding plants only what they can absorb. The state report also suggests using nitrate-laden ground water for irrigation. Plants absorb the nitrate from the water, and clean water returns to the aquifer.
Lacking a home nitrate test kit for my garden, I’ll choose organic fertilizer when it comes time to feed my plants again. That should give my plants a slow drip of nitrogen and hopefully prevent a build up of excess nutrients. I feed my plants nitrogen so they’ll be strong and healthy enough to produce food for me.
Bring on the orange carrots, yellow peppers and purple beans!
Cleantech firms are sometimes criticized for pie in the sky thinking. Harvest Power, though, looks like a pretty down to earth company. It makes dirt*. Mind you, this is high quality dirt*.
Late last week, Harvest Power said it had raised $110 million in a third round of venture capital funding. That’s a tidy sum for a messy business. Harvest is an industry that some call “organics management.” According to the firm’s website, it works at a community level to gather and re-use organic materials (food waste, lawn clippings, pieces of lumber). It produces mulches, organic fertilizer, and soil products using composting and anareobic digestion.
These technologies are not exactly new. But it seems that the value is in its system approach and its facilities. Harvest ties into local communities where organic materials are separated from the waste stream. In addition to recyling the waste into soil-related products – which it sells to local farmers and gardeners - its digestors produce renewable energy from biogas.
The biogas is used in combined heat and power plants, exported as pipeline-grade (i.e. purified methane) natural gas, or compressed gas to be used for transportation. High heat content materials like wood chips are also processed into fuel for use in industrial boilers.
According to PrivCo, a firm that tracks the finances of privately-held companies, Harvest can boast significant revenues (this contrasts the firm with some cleantech plays that go public before making any money from sales). Founded in 2008, it made close to $50 million last year and is expected to rake in $75-$100 million in 2012.
The financing will be used by the company to expand its reach. PrivCo reports Harvest is finishing two Canadian energy plants and has plans for waste to energy facilities in New Jersey and Florida.
* [update] Harvest actually produces soil, as The Phytophactor points out in his comment.
[you can skip my musings and go straight to Alex's compostable plastics story!]
Today’s forecasted high temperature where I live in the Northeast is 78 degrees. That just doesn’t seem right. This time last year, we still had an impressive layer of snow which didn’t melt until sometime in April. [insert random thoughts of global warming, La Nina, and how yesterday was almost 20 degrees warmer than the forecast promised]
Over the weekend I took the opportunity to turn my compost pile. It’s got mostly kitchen scraps, a few bits of brown paper bag (worms love ‘em) and leaf litter. Home composting is both an art and a science – my pile had too much nitrogen and not enough carbon, so I added more dried leaves.
I also noticed a plastic spoon in the pile, normally a no-no. But this one was made of PLA, a plastic derived from corn that is supposed to be biodegradable. It still looked pretty new, though, mostly because my backyard pile cannot reach the high temperature and rabid microbial activity of an industrial scale composting operation.
If I lived in San Francisco (and today it feels like I do!) I would put the spoon and my kitchen scraps, and perhaps some lawn wastes into a compostable plastic bag and set it out to be picked up. This week’s issue of C&EN features an in-depth, fascinating story by Alex Tullo on how compostable plastic trash bags – plus disposable dinner ware – can enable cities to divert 50% or more of trash away from landfills.
From the story:
In a landfill, food scraps generate methane, a much more potent greenhouse gas than CO2. They also form acids that leech out of landfills. “If you ask all these cities what the largest component of their waste going to the landfill is, it’s food,” he says. “And what is one of the worst things to go to the landfill? It’s food. The only thing worse is hazardous waste.” [quote from Jack Macy, commercial zero-waste coordinator for SF Environment, San Francisco’s environmental department.]
Now think about your household’s waste. To reach San Fran’s goal of diverting 100% of municipal trash from landfills, it would have to be either recycled or composted. Plastics can be recycled, but if they get into the composting supply (like a random fork, or the trash bag holding the food waste) then you’ve already broken your system.