organic – The Garden Professors™

The Scoop on Poop: Manure in the Vegetable Garden (and potential food safety risks)

“Can I use manure to fertilize my garden?” That’s a common question we get in Extension and on the Garden Professors page. The answer is absolutely, but there’s a “but” that should follow that answer that not everyone shares. And that is…but for fruits and vegetable gardens the manure you apply could be a potential source of human pathogens that could make you or your family sick. There are procedures and waiting periods you should follow to reduce the potential risk to human health from pathogens in manure and other animal products.”

Why manure?

First, application of manures to garden and farm production spaces is a good use of nutrients and provides a way to manage those nutrients to the benefit of growers and the environment. Using the concentrated nutrients in the manures to grow crops reduces what washed downstream in the form of pollution. In addition to adding nutrients to the soil, application of manure and other animal byproducts (bone meal and blood meal, for example) add organic matter to the soil, which improves soil texture, nutrient retention and release, and supports beneficial microorganisms.

Typical N-P-K composition for some manures and composts. Source: UC Davis

For organic production, both in home gardens and on farms (certified organic or not), manure and animal products are an important input for fertility. For the most part, manures offer a more concentrated (higher percentage) of nutrients by weight than composts composed only of plant residues, so less is usually needed (by weight) than plant composts to apply the same amount of nutrients.

While the nutrient levels of manures and composts can be highly variable, there are some general ranges that you can use to plan your application based on the needs you find in your soil test. (And you should be doing a soil test, rather than just applying manure or compost willy-nilly. Just because the nutrient concentrations are lower than a bag of 10-10-10, you can still over-apply nutrients with composts and manures).

So what are the hazards?

As you’ve probably realized from bathroom signs and handwashing campaigns, fecal material can carry a number of different human pathogens such as E. coli and Salmonella. The major risk around application of manures to edible crops is the possible cross-contamination of the crop with those pathogens. The number one hazard leading to foodborne illness from fresh produce is the application of organic fertilizers – mainly manure, but also those other byproducts like blood meal and bone meal. Add in the fact that the consumption of raw fruits and vegetables has increased over the last decade or more, and you’ll soon understand why Farmers who grow edible crops must follow certain guidelines outlined in the Food Safety Modernization Act (FSMA, which you’ll hear pronounced to as fizz-mah) to reduce the potential risk that these pathogens pose to people who eat the crops. Right now, only farms with a large volume of sales are required to follow the guidelines, but smaller producers are encouraged to follow them as best practice to reduce risk and liability. And while there isn’t a requirement for home gardeners to follow the guidelines, it is a good idea to understand the risks and incorporate the guidelines as best practice. It is especially a good idea if the produce is being eaten by individuals who are at higher risk of foodborne illness – young children, the elderly, or those who are immunocomprimised.

The recommendations are also suggested when there’s contamination from unexpected or unknown sources like when vegetable gardens are flooded (click here for a recent article I wrote to distribute after the flooding in Nebraska and other midwestern states).

Recommendations to reduce risk

As previously stated, while these recommendations have been developed for produce farmers, research showing the potential hazards of applying manures means that it is a good idea for home gardeners to understand and reduce risks from their own home gardens.

The set of guidelines outlined by FSMA cover what are called Biological Soil Amendments of Animal Origin (BSAAO – since we government types love our acronyms). Here’s the “official definitions” used in the rules for produce farming:

A Biological Soil Amendment is “any soil amendment containing biological materials such as stabilized compost, manure, non-fecal animal byproducts, peat moss, pre-consumer vegetative waste, sewage sludge biosolids, table waste, agricultural tea, or yard trimmings, alone or in combination”.

A Biological Soil Amendment of Animal Origin is “untreated: cattle manure; poultry litter; swine slurry; or horse manure.”

Image result for manure — Now that’s a pile of crap!

For BSAAO (we’ll call it raw manure), manure should only be applied to the soil and care should be taken not to get it on the plants. There’s also a waiting period between applying the manure and when you should harvest the crop. The length of the waiting period depends on whether the edible part of the crop comes in direct contact with the soil. Right now the USDA is still researching the appropriate waiting period between application and harvest, so the general recommendation until then is to follow the standards laid out in the National Organic Program (NOP) standards. Research shows that while pathogens may break down when exposed to the elements like sun and rain, they can persist for a long time especially in the soil.

For now, here are the recommendations:

For crops that contact the soil, like leafy greens (ex: lettuce, spinach, squash, cucumbers, strawberries) the suggested minimum waiting period between manure application and harvest is 120 days.

For crops that do not contact the soil (ex: staked tomatoes, eggplant, corn) the suggested minimum waiting period between manure application and harvest is 90 days.

For farmers following FSMA, the waiting periods could change when the final rule is released – some early thoughts are that it could increase to 9 – 12 months if the research shows a longer period is needed.

What about composted manure? Is it safe? The guidelines indicate that there isn’t a waiting period between application of manure that has been “processed to completion to adequately reduce microorganisms of public health significance.” But what does that mean? The guidelines lay out that for open pile or windrow composting the compost must be maintained between 131°F and 170°F for a minimum of 15 days, must be turned at least 5 times in that period, must be cured for a minimum of 45 days, and must be kept in a location where it can’t be contaminated with pathogens again (animal droppings, etc). Farmers have the added step of monitoring and thoroughly documenting all of the steps and temperatures. Now we know that that’s a bit of overkill for home gardeners, but suffice it to say that the cow manure that’s been piled up to age for a few years that you got from the farm down the road doesn’t meet that standard.

Image result for compost — Failure to maintain proper temperature on composted manure could mean that your goose is cooked, though this thermometer doesn’t have that setting.

“Aged” manure ≠ “processed to completion to adequately reduce microorganisms of public health significance.” So unless you know for sure that you’ve reached and sustained the appropriate temperatures in your compost, you should assume that it would be considered a BSAAO subject to the 90/120 waiting period. Bagged manure you buy at the garden center is likely to be composted “to completion” or may even have other steps to reduce pathogens like pasteurization. Sometimes the label will indicate what steps have been taken to reduce pathogens, or even state that it has been tested for pathogens.

The recommendations also specifically mention compost teas and leachates (a topic we handle with much frequency and derision here at the GPs, since there’s not much science to back up their use and I mention here with much trepidation). For the sake of food safety, any tea or leachate should only be applied to the soil, not the plant. And for home compost that doesn’t even contain animal manure the 90/120 day waiting period should still be observed in most cases since some of what goes into home compost is post-consumer. Since we put pieces of produce in there that we’ve bitten from or chewed on (post-consumer), plus some animal origin items (eggshells) there’s the potential that we could contaminate the compost with our own pathogens – and the environment is perfect for them to multiply.

The Bottom Line

While these guidelines and rules for farmers may just be best practice recommendations that we can pass on to home gardeners, common sense tells us that taking precautions when applying potential pathogens to our edible gardens. An ounce of prevention is worth a pound of cure, especially when were talking about poop.

Sources/Resources:

Produce Safety Alliance producer training materials
National Good Agricultural Practices Program: Soil Amendments (Cornell)
Biological Soil Amendments of Animal Origin (FDA Fact Sheet)
FSMA Final Rule on Produce Safety (FDA)
Manure in Organic Production Systems (ATTRA)

Translating the Language of Seed Packets: Hybrid, Heirloom, non-GMO, and more

Hybrid, heirloom, organic, non-GMO, natural….there’s lots of labels on those seed packets or plants you pick up at the garden center or from your favorite catalog. Since the seed-starting season is upon us, let’s take a minute to look at some of the information – and mis-information – you might find on those seed packets.

For a brief overview, here’s a short video segment I recently shot for the Backyard Farmer Show, a popular public TV offering for Nebraska Extension:

Hybrid vs. Heirloom vs. Open Pollinated

Just what is a hybrid anyway?

Simply put, a hybrid is a plant (or any living organism, technically) with two different parents. Take for example the Celebrity variety of tomato, which is very popular among home gardeners. In order to get seeds of Celebrity tomatoes, whoever produces the seeds must always cross two specific parent plants to get those specific seeds, called an F1 hybrid.

These parents have been developed through traditional breeding programs (read: the birds and the bees — no genetic engineering here) from many different crosses. Hybridization has occurred naturally ever since there were plants. Man has been directing this process throughout most of his agricultural history to get better crop plants. How else would we have many of the vegetables and fruits that we take for granted today?

Crops like corn have very little resemblance to its wild counterpart, many thanks to selection and even crossing of superior plants by humans over the centuries. University researchers and seed developers use this natural ability of plants to cross to direct the formation of new varieties that improve our ability to produce food.

What is an heirloom?

Perhaps the first question we should ask is, what is an open-pollinated seed? An open-pollinated variety is one whose genetics are stable enough that there is no need for specific parent plants, because the seeds produced from either self-pollination (as in the case of beans and tomatoes) or cross-pollination with the same variety will produce the same variety.

An “heirloom” plant is basically an open-pollinated plant that has a history, either through age (50-plus years) or through heritage (it has a family story).

Take for example the Mortgage Lifter tomato.

Mortgage Lifter Tomato Source: https://www.flickr.com/photos/blewsdawg

It was developed by a gentleman living in West Virginia (my native state -there are two competing stories as to who developed it). For all intents and purposes, the Mortgage Lifter started out as a hybrid, since the gardener in question developed the tomato by crossing many different varieties to find one that he liked. He sold so many of them to his neighbors that he was able to pay off the mortgage…thus its interesting moniker.

It just so happened that the genetics of this tomato were stable enough that its offspring had the same characteristics, so seeds could be saved. Therefore, it was technically an Open-Pollinated variety. Over time, the tomato became considered an heirloom because of both its age and unique story. This story has played out many times, in many gardens and in many research plots at universities.

There are some trying to revive the practice of plant breeding for the home gardener. If you’re interested, check out the book “Plant Breeding for the Home Gardener” by Garden Professor emeritus Joseph Tychonievich. Who knows? Maybe in 50 years we will be celebrating your plant as a distinctive heirloom.

So which is better – Heirlooms or Hybrids?

There are pros and cons to hybrid plants and heirlooms both, so there really isn’t an answer as to which one you should plant. It really boils down to personal choice. Hybrid plants tend to have more resistance to diseases and pests, due to the fact that breeders are actively trying to boost resistance. This means that there will be higher-quality produce fewer inputs. This is why hybrids are popular with farmers — nicer, cleaner-looking fruits with fewer pesticides. Many times hybrids are also on the more productive side, thanks to a phenomenon called hybrid vigor.

Heirlooms, on the other hand, help preserve our genetic diversity and even tell our cultural story. Heirlooms do not require a breeding program, so there is built-in resilience, knowing that we can produce these seeds well into the future with little intervention. But we do have a trade-off with typically less disease-resistance and less consistency on things like yield. Since they are open-pollinated, they are often a good choice for people who enjoy or rely on saving seeds from year to year.

GMO-Free or Non-GMO

As we have pointed out several times before, when it comes to seeds for home gardeners, the label of GMO-Free is largely meaningless and sometimes mis-leading. Whether or not you believe the prevailing science that shows that genetically engineered plants are safe for human consumption, you can rest assured that there are currently no genetically engineered seeds or plants available to home gardeners. Not on the seed rack at the box store nor your local garden center. Not in a catalog or online.

Here are two assurances to that statement: A majority of the things that you grow in the home garden don’t have a genetically engineered counterpart. Only

Source: USDA Animal and Health Inspection Service

12 genetically engineered crops have been approved in the US, and only 10 of those are currently produced. Most of these are commodity crops that home gardeners would not even produce, such as cotton, sugar beet, canola, and alfalfa. A few more have counterparts that are grown by home gardeners, but are vastly different from those grown by commodity producers (soybeans vs. edamame soy). And some just aren’t that very widespread (there are some GE sweet corn cultivars and squash cultivars, but they aren’t widespread on the market).

So for the most part, there aren’t any “GMO” counterparts to the crops you’d grow in the home garden. They don’t exist.

The other assurance is that genetically engineered crops are not marketed or sold to home gardeners as a matter of business practice or law. In order to purchase genetically engineered seeds or plants, it is current practice in the United States that you must sign an agreement with the company that holds the patent stating that you will not misuse the crop or propagate it (and before we get into the whole intellectual property argument – plant patents and agreements like this have been around since the early 1900s – it isn’t new). So you know that you aren’t buying genetically engineered seeds since you aren’t being asked to sign an agreement. Plus, these companies make their money by selling large quantities of seeds, they just aren’t interested in selling you a packet of lettuce seeds for $2.

So since there aren’t any GMOs available to home gardeners, why do all these seed companies slap that label on their packets? Marketing, my dear! It started off with just a few companies, mainly using the label to compete in a crowded market. And fear sells. The label has spread to more and more companies as this fear and anti-science based marketing ploy has spread…both by companies who jumped on the fear bandwagon and by those who took so much harassment from the followers of the non-GMO crowd or they lost sales to people sold on the non-GMO label that they finally gave in. Unfortunately for some companies, slapping the non-GMO label on a product seems to give them permission to charge more, even if has no real meaning….so buyer beware.

Treated vs Non-Treated

Image result for treated seed — Treated seed Source: pesticidestewardship.org

Seed treatment usually involves the application of one or more pesticide such as a fungicide or insecticide to protect against pathogens or pests, mainly in the early stages of growth. A good example would be if you’ve ever seen corn, pea, or bean seeds at the local feed or farm store that are bright pink or orange in color. These seeds have been treated with a fungicide to offer short-term protection against damping off. Some crops are also treated with systemic insecticides, such as imidacloprid, to protect against insect damage. There’s been a big emergence of organic seed treatments, so treatment doesn’t necessarily mean the crop can’t be labeled organic.

Treated crops are most-commonly found at farm supply stores and aren’t generally marketed directly to home gardeners. You’ll likely not find them at most box stores or garden centers catering exclusively to gardeners. Many packets will specify whether they are non-treated or treated.

Organic and Natural

In seeds, the term Organic largely refers to seeds harvested from plants that were certified organic. Generally speaking, these seeds were produced on plants that received no synthetically produced fertilizers or pesticide sprays. However, it does not mean that the plants were not treated with pesticides. There’s a great misunderstanding about organic production – there are a number of pesticides and even seed treatments approved for use on organic crops. Typically, they are produced from a plant or microorganism extract, naturally occurring mineral, or other organic derivative. So organic does not equal pesticide free (on the seed rack or on the grocery shelf).

There are a few different levels of “organic,” too.

Sometimes small producers use the label in a general sense to mean that they follow organic practices, but aren’t certified. The process for certification is often onerous and costly for small producers, so they often opt to not get it. This is especially true for producers that market exclusively to a local clientele, like at the farmers market, where they can rely on their relationship with customers and reputation to speak for their practices. Some food companies may also use a simple “organic” label – either as a design choice, or because their product wouldn’t qualify for a certification.

“Certified organic” means that the producers practices have been certified to meet the requirements laid down by a certifying agency. A certifying agency could be a non-profit or a state department of agriculture. The requirements and practices vary from entity to entity.

“USDA Certified Organic” means that the producer has been certified by the USDA as a follower of the guidelines set forth by the National Organic Program (NOP). This is usually seen as the most stringent of the certifications, and is standardized nation-wide.

For certified organic producers, a requirement for production is that all seeds or plant sources are organic. For home gardeners, I often question the need for organic seed, even if organic methods are followed. A quick literature search turned up no evidence that garden seeds contain pesticide residues. There’s been no evidence that plants translocate systemic pesticides to their seeds or fruits(Though it is impossible to prove a negative). Since seeds are located inside some sort of fruit, there would be little chance of residue on the seed from a pesticide application. And even if there was some sort of residue, it would be such a small amount in the seed that it would be so dilute in the mature plant that it would likely be well below any threshold of threat to human or wildlife health…or even measurability.

Personally, I may opt for the organic seed at home if it were the same price of the “conventional” on offer…but that organic label often includes a pretty good price differential. Knowing that there likely isn’t a huge difference in what is in the packages….my penny-pinching self will reach for the conventional, cheaper option.

And what about “natural.” That one’s easy….there is no recognized definition of natural by the USDA or any other body. Companies use that term to mean whatever they want it to mean….meaning that it is relatively meaningless in the grand scheme of things.

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Managing Diseases without Fungicides: A Focus on Sanitation (A Visiting Professor feature)

Submitted by:
Nicole Ward Gauthier, University of Kentucky Extension Plant Pathologist
PEOPLE: University of Kentucky Department of Plant Pathology Website
Kentucky Diseases of Fruit Crops, Ornamentals, & Forest Trees on Facebook
Amanda Sears, Kentucky Extension Horticulture Agent
Madison County Cooperative Extension Website

Alternatives to Fungicides

When diseases occur in urban landscapes, it is often presumed that fungicides are the most important and effective disease management tools available. However, a good sanitation program can help reduce the need for chemical controls and can improve the effectiveness of other practices for managing disease. This often-overlooked disease management tool reduces pathogen numbers and eliminates infective propagules (inoculum such as fungal spores (figure 1c) , bacterial cells; virus particles; and nematode eggs) that cause disease.

fig 1b marigold botrytis 1525420 (MC Shurtleff, UIll bugwd) (640x412) — Figure 1a. Marigold blossom infected with Botrytis

Figure 1b. Pathogen levels can build up on marigold flowers if diseased tissue is left in the landscape

close up of infecting spores — Figure 1c. Infecting spores on plant surface

Certain foliar fungal and bacterial leaf spots can become prevalent during rainy or humid growing seasons. When disease management is neglected, pathogen populations build-up and continue to increase as long as there is susceptible plant tissue available for infection and disease development (Figures 1a-c). Infected plant tissue infested soil and pathogen inoculum all serve as sources of pathogens that can later infect healthy plants.

Figure 2. Fallen leaves can serve as a source of inoculum (fungal spores) for additional infections. Many pathogens overwinter in fallen debris and then produce infective spores the following spring.

Reduction of pathogens by various sanitation practices can reduce both active and dormant pathogens. While actively growing plants can provide host tissue for pathogen multiplication, dead plant material (foliage, stems, roots) can harbor overwintering propagules for months or years (Figure 2).

These propagules can travel via air/wind currents, stick to shoes or tools, or move with contaminated soil or water droplets. Thus, prevention of spread of pathogens to healthy plants and the elimination of any disease-causing organisms from one season to another are the foundations for a disease management program using sanitation practices.

Sanitation Practices

Elimination and/or reduction of pathogens from the landscape results in fewer pathogen propagules. The following sanitary practices can reduce amounts of infectious pathogens:

Figure 3a. Cankers are common overwintering sites for disease-causing pathogens

Remove diseased plant tissues from infected plants. Prune branches with cankers (Figure 3a) well below the point of infection (Figure 3b). Cuts should be made at an intersecting branch. Rake and remove fallen buds, flowers, twigs, leaves, and needles.

Figure 3b. Remove infected branches, making cuts well below points of infection

Disinfest tools used to prune galls and cankers. Cutting blades should be dipped into a commercial sanitizer, 10% Lysol disinfectant, 10% bleach, or rubbing alcohol between each cut.
If using bleach, rinse and oil tools after completing work, to prevent corrosion.
Discard perennial and annual plants that are heavily infected and those with untreatable diseases (e.g. root rots, Figure 4; and vascular wilts). Dig up infected plants to include as much of the root system as possible, along with infested soil.

Figure 4. Heavily infected plants or those with untreatable diseases, such as black root rot (images left and right), should be removed from the landscape.

Trees and shrubs infected with systemic diseases (e.g. Dutch elm disease, Verticillium wilt, bacterial leaf scorch) that show considerable dieback should be cut and the stump removed or destroyed (e.g. by grinding).
If infected plants are to be treated with fungicides, prune or remove infected tissue (flowers, leaves) and debris to eliminate sources for spore production or propagule multiplication. This should be done before fungicide application. Fungicide effectiveness may be reduced when disease pressure is heavy, which can result when pathogen levels cannot be reduced sufficiently by chemical means (fungicides).
Discard fallen leaves, needles (Figure 5), prunings, and culled plants. Never leave diseased plant material in the landscape, as pathogens may continue to multiply by producing spores or other propagules. Infected plant material should be buried, burned, or removed with other yard waste.

pathogen 1 pathogen 2

Figure 5. Black fruiting structures of the pine needlecast pathogen contain spores (images left and right). Removal of infected plant tissue helps reduce amounts of inoculum in the landscape.

Do not compost diseased plant material or infested soil because incomplete composting (temperatures below 160˚ F) may result in survival of propagules.
Homeowners should be cautious about storing diseased limbs and trunks as firewood or using the woodchips as mulch. For example, wood from trees infected with Dutch elm disease should be debarked before placing in a firewood pile.
Remove weeds and volunteer plants to prevent establishment of a “green bridge” between plants. A green bridge allows pathogens to infect alternate hosts until a more suitable one becomes available. Be sure to remove aboveground parts AND roots.
Soil from container-grown plants should not be reused from one season to the next because pathogens can survive in soil.

Additional Resources:

University of Kentucky Extension Plant Pathology Publications

Photo credits:

R.K. Jones, North Carolina State University (Fig. 1A), courtesy Bugwood.org
M.C. Shurtleff, University of Illinois (Fig. 1B), courtesy Bugwood.org
David Cappaert, Michigan State University (Fig. 1C), courtesy Bugwood.org
Theodor D. Leininger, USDA Forest Service (Fig. 2), courtesy Bugwood.org
Joseph O’Brien, USDA Forest Service (Fig. 3, right), courtesy Bugwood.org
Elizabeth Bush, Virginia Tech (Fig. 4, left), courtesy Bugwood.org
Bruce Watt, University of Maine (Fig. 4, right), courtesy Bugwood.org
Andrej Kunca, National Forest Centre, Slovakia (Fig. 5, left), courtesy Bugwood.org
Robert L. Anderson, USDA Forest Service (Fig. 5, right), courtesy Bugwood.org
John R. Hartman, University of Kentucky (Fig. 3, left)

pdf Managing Diseases Without Fungicides

Organic insecticides that will get you high

Plants are crazy chemical factories, synthesizing a whole host of compounds that we use for flavoring and dye and medicine and… getting high. And why are they making all these chemicals? They’re certainly aren’t doing it for our sake… no, quite often they’re trying to kill something – usually insects — and it just so happens that sometimes our brains and bodies react differently enough that instead of killing us, they make us high. Well, and sometimes they kill us too.

Nicotine, the addictive force behind cigarettes, is a potent natural insecticide. if you’ve heard of neonicotinoids, the pesticides that some are concerned with in relation to honey bee health, they’re synthetic insectides based on the chemistry of nicotine, and like it, they effectively kill insects. No word on if anyone has tried smoking them yet.

Opium poppies are full of a thick latex loaded with chemicals like morphine and codeine, to name a few, which are obviously used as pain killers, and of course opium is taken directly or processed into more potent forms like heroin. The research on these chemicals indicates multiple possible functions, acting to prevent damage by herbivores (like insects), and possibly also acting to prevent pathogen damage and maybe even a more structural function in strengthening cell walls in response to damage (see: http://pubs.acs.org/doi/abs/10.1021/np020583l) I didn’t find any research looking directly at opium’s ability to kill insect pests. Probably because that type of research is usually aimed at a practical solution to pest problems, and even if heroin proves to be a potent insecticide, I doubt anyone would issue and extension bulletin recommending you use it to control your whitefly…

But that lack of practical application didn’t stop a researcher from publishing a paper titled Cocaine as a Naturally Occurring Pesticide in which they found that cocaine was highly effective in killing tomato hornworm! Organic growers, take note! Maybe THAT’S why organic tomatoes are so expensive at the farmers market…

In any case, it is fascinating to note all the interesting, sometimes useful, often dangerous chemicals that have evolved thanks to the on-going chemical arms race between plants and the things that try to eat them. We’re the accidental beneficiaries – and sometimes victims – of that very, very old battle.

New publication on biodynamics

Happy New Year to our blog readers!

Now that we have our blog safely moved to this new format, we all resolve to post more frequently. (It’s actually Bert’s day to post, but given that his computer is probably frozen – literally – in Michigan, I’ll step in.)

Today I got a link to my most recent publication in HortTechnology on the science behind biodynamic preparations. I’ve written about this topic before, but recognize the importance of peer-reviewed information for researchers, extension educators, and Master Gardener volunteers. Not to mention all the gardeners who rely on us to provide good science for gardens and landscapes. So here it is. I’m planning to continue submitting review articles to HortTechnology on other topics of interest. It looks like permaculture might be the next one up.

So enjoy this article – pass it on to others who are curious about biodynamics, and if you are a Master Gardener be sure to take it to your MG coordinator and ask that it becomes a resource for your program.

Conventional vs. organic agriculture – the battle continues

An article was published earlier this week comparing the nutritional content of milk from organically raised cows to that from conventional dairies. The principle finding in this report is that “organic milk contained 25% less ω-6 fatty acids and 62% more ω-3 fatty acids than conventional milk, yielding a 2.5-fold higher ω-6/ω-3 ratio in conventional compared to organic milk (5.77 vs. 2.28).” (ω-3 fatty acids are considered to be “healthy” and you’ve probably heard of them in association with fish consumption.)

Of course, the popular press has had a field day with this, with such headlines as “Study finds organic milk is more nutritious.” This of course is nonsense, because the researchers didn’t study the health effects on people consuming the milk. But for argument’s sake, let’s assume this might be true and move on to the study itself.

What researchers actually found was that cows who feed primarily on pasture grasses and other forages (the “organic” cows) had elevated ω-3 fatty acids compared to those receiving a primarily grain-based diet (the “conventional” cows). This isn’t new information – other studies (such as this one) have consistently demonstrated this.

The problem with this newest paper is the inaccurate terminology used to describe the study. It really has nothing to do with whether the cows are raised organically or conventionally – it has to do with what they eat. A better experimental design would have included multiple comparisons among “organic” cows (who by default are grass-fed), “conventional” cows that are fed a grain diet (typical with large operations), and “conventional” cows that are pasture-raised (common with smaller farms that don’t want to jump through the organic certification hoops). I’m betting that the milk from this last group of cows wouldn’t be much different from the “organic” cows.

The upshot of using such imprecise terminology is that the message is lost amid the furor of the ongoing organic vs. conventional agriculture battle. Readers erroneously jump to a value-based conclusion – i.e., organic is “better” than conventional.

In my opinion, there’s no excuse for this. The experts who reviewed this article should have pointed out the loaded language and insisted on a change in terminology. (You might be interested to follow the comments on this article, one of which alludes to misleading terminology.)

Why I Don’t Worry Too Much About Organic Fruits and Veggies

Let me tell you something you already know. If you grow something in your own garden you’ll know exactly what poisons were or weren’t put on it, how much fertilizer was used, and furthermore it will taste better.

If you buy your apples from the guy down the street who you’ve known for 20 years you’ll be able to ask him what he used to grow the crop, why he used it, and you’ll have the satisfaction of supporting a local industry. And yes, those apples will taste better than grocery store apples.

If you go to a farmers market you’ll be able to ask the people there exactly what they did to their crops, and why they did what they did. And you’ll feel good about supporting the local economy. And yes, the food will taste better than anything from the grocery store.

If you walk into a grocery store or Target, or Kmart or whatever and pull a fruit or vegetable off the shelf which has the USDA Organic Label on it and say to yourself “Hey, I’m doing something good for my family and the environment” then, in my opinion, you’re fooling yourself.

There, I said it. I believe that, AS USDA ORGANIC CERTIFICATION NOW EXISTS, the USDA Certified Organic label does not provide a significant indicator that the fruit or veggies you’re buying provide a significant benefit in terms of human or environmental health. Please note that I’m not saying anything different than our government does – what they say is: “Organic is a labeling term that indicates that the food or other agricultural product has been produced through approved methods that integrate cultural, biological, and mechanical practices that foster cycling of resources, promote ecological balance, and conserve biodiversity.”

Notice that they never say that organic is superior to conventional production, simply that organic uses practices that “foster cycling of resources, promote ecological balance, and conserve biodiversity”. Though many of you may not believe it, conventional growing uses many of these practices too – producers know that if they don’t pay at least some attention to sustainability then they will lose money over time.

So why am I talking about this today? Well, I’ve had a few requests to discuss that new meta-study that came out a few weeks ago which showed that organic food has the same nutritional value as food produced conventionally. Big deal. Plenty of other meta studies have shown essentially the same thing –the quality of organic is LARGELY the same as conventional with a few nutrients (often vitamin C) a little higher in organic and a few (often protein levels) being higher in conventional. Anyway, to make a long story short, I don’t know why this study got more press – maybe they have better PR people at Stanford where the study was put together.

Look, the reason that one food has more nutrients than another has much more to do with the food itself than whether the food was grown organically or conventionally. No matter how you treat a McIntosh apple, it will never have as much vitamin C as a Granny Smith apple. Period. Folic acid will always be greater in bananas than grapes. Period. If you’re worried about getting enough of a particular nutrient then eat foods high in that nutrient. If you’re worried about a lot of nutrients then eat a varied diet.

Of course the study also says that synthetic pesticides are more likely to be on conventionally produced foods than organically produced foods. OK, I’ll buy that. Makes perfect sense….but tell me, how much organic pesticide is on organically produced foods? And how does it affect you? If a farmer uses spinosad, an insecticide used by organic growers, it can be present at low levels in food, as can other organic pesticides such as pyrethrum. But since residues of these organic pesticides are rarely tested you have no idea how much is in there.

Look, if you want to avoid pesticides on your fruits and veggies altogether and can’t grow a garden or go to a farmer’s market, then you should avoid foods where pesticides need to be used. These are the only foods where you can count on growers, organic or conventional, avoiding pesticides (No farmer WANTS to use pesticides – they’re expensive!). To find foods where pesticides are less likely to be used just go to that crazy dirty dozen list which the Environmental Working Group puts out (which I think is a bit ridiculous – but I’ll leave that alone for now since this post is getting long) and select fruits and veggies from the clean 15.

In terms of organic production being better for the environment, as long as organic growers can use copper to control diseases, I’m concerned about how long term applications of this copper will affect
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soils on land devoted to organic production over the long term. I’m also concerned about fertilizer runoff and leaching in organic production – same as in conventional production. Nitrogen and phosphorus from manure can and do run off just the same as nitrogen and phosphorus from synthetic fertilizer.

In both conventional and organic systems, the impact that production has on the environment comes down to the responsibility that a given producer takes for doing the right thing and protecting the environment. To say otherwise is just silly. There is so much leeway in the USDA organic system that there is plenty of opportunity for a USDA organic producer to do things that will make their operation significantly worse for the environment than a conventional producer of the same crops.

So…How Much Pesticide Is Actually In Our Fruits and Veggies?

We have discussed the dirty dozen here before – those foods which a group called The Environmental Working Group (wow—fancy name – everything they say must be true!) has established contain more residues of different pesticides than other foods. I’ve already stated my concerns about selecting organic foods instead of conventionally grown ones because of a fear of pesticides so I won’t restate that here. Instead what I want to call your attention to an article sent to me by our visiting professor, Charlie Rowher. This article runs down the amounts of pesticides that are actually in the dirty dozen. And the thing is….there just isn’t much pesticide of any sort on most foods and there is no evidence at all that eating these levels of pesticides would be bad for us in any way – even if we ate them in copious amounts day after day.

To be honest I think the authors of this article go a little too far – I do think that there is some potential for damage even from the ultra-small pesticide doses that we find on our foods. But their points are well taken – the amount of pesticides in food is miniscule and less likely to be damaging to us than a great host of other things. I’m much more concerned about certain segments of our population suffering malnutrition from avoiding conventionally grown fruits and veggies than I am about the larger portion of our population getting cancer from eating them.

Guano

One of the best organic fertilizers out there – at least in terms of how plants respond to it — is bat guano. As most of you probably already know, bat guano is made of bat droppings. What you probably don’t realize is that bat droppings need to be aged for a while in an arid environment before they become guano. Caves provide the perfect environment for this to occur, and so that is where most bat guano comes from.

Because guano needs to be aged in special surroundings before it is used it is not a rapidly renewable resource. Instead it’s kind of like peat in that it takes anywhere between decades and thousands of years for the raw material from which it is made to develop into the stuff that we use. Furthermore, by harvesting bat guano we can actually damage the ecosystems present in the caves from which the bat guano is harvested. Think about it – bats generally feed outside the cave, so when they defecate inside the cave they are actually bringing new nutrients into the cave – nutrients that other creatures can use. Whole ecosystems are based on this poo! So when we harvest bat guano from a cave what we are doing is disturbing a specialized ecosystem – a very unique system.

So am I encouraging you away from bat guano? No more than I would encourage you to consider reducing your usage of peat – or of oil — or any other non-renewable resource. I can’t deny that it’s a great fertilizer, but if you want to use an organic fertilizer why not at least consider one that is renewable instead of one that is from a limited resource and which may cause harm to a unique ecological system?

Organic Honey?

As there seems to be a good deal of interest in the topic of honeybees, and I’m a beekeeper, albeit relatively novice, I thought I might continue a bit of discussion.

I’ve been beekeeping for three years, and I sold my first honey harvest this fall. Six gallons, divided into pint and half pint-sized jars. As a newbie, extracting the honey from the frames and getting it into the jars was, by far, the messiest thing I’ve ever done. It’s like wrestling with a living thing…the garage and kitchen still have sticky spots. It also took forever – honey moves through a three- pail, three-filter system (eventually removing particles down to 200 microns) like…cold molasses. Once it was properly subdued and contained, I looked into what was required for labeling. Very interesting. And very, very, vague.

Honeybees have been described as “flying dust mops” – there is no way, unless the beekeeper owns all the land in a several-mile radius, that one knows what they’re getting into. Our girls’ primary duty is pollination of our four+ acres of blueberries, so their primary pollen and nectar source in late spring is our four acres of blueberries. After that, they hit the sourwood, wingstem, mountain mint, and the smorgasbord of of perennials and annuals in the garden borders. We don’t use any pesticides on our farm (the cabbage looper and stink bug invasion this year is really testing me on that one). But that doesn’t mean the gentleman next door isn’t using Sevin on his squash or pyrethrins on his potatoes. And our bees are just as likely to be over at his house as ours (despite my stern lecture to them).

Noticing the honey labeled “USDA Certified Organic” sold for a premium at both my local grocer and favorite “natural foods” store, I spent some time digging as to certification standards, and whether it would be worth it to get certified.

I came up fairly empty-handed. There does not seem to be any USDA National Organic Program certification standards for honey. Apparently there are some trade-law guidelines that allow honey to be imported from Canada and Central/South America labeled as USDA organic. Very confusing, and very weird. But apparently some U.S. honey producers, both large and small, have gone ahead and slapped USDA Organic labels on anyway. Along with other meaningless statements like “Superior grade” or “All natural”. Some states such as Pennsylvania are pushing for NOP standards, noting their beekeepers are at a disadvantage, marketing-wise, if they cannot certify their honey but Canadian or Argentine producers can. On another front, beeswax, especially older wax in frames that are in brood hives for several years, can accumulate pesticides brought in from foraging bees like nobody’s business. So I’d also look askance at claims of products containing “organic beeswax.”