Hello Again, and a fun article that was called to my attention.

By Jeff Gillman (posted by Linda C-S, who has taken liberties with using photos from UNC Charlotte gardens that have nothing to do with Jeff’s post.)

Living arch at UNC Charlotte gardens

It has been almost two years since I have had the chance to post anything as a Garden Professor. Since then I’ve taken a job as the Director of UNC Charlotte Botanical Gardens and there are all kinds of things I’d like to share with you, and perhaps sometime over the next few weeks and months I will, but for now what is probably most pertinent is that I absolutely love my job. I am still doing some work on garden myths, but what I’m finding more entertaining is investigating the histories of different plants and their interactions with humans. In fact, in about a month or so, my friend Cindy Proctor and I will be releasing a podcast titled The Plants We Eat that investigates the interesting history, culture and biology of the various plants we use for food. We’ve already recorded shows on strawberries, grapes and mad honey, and we’ll be doing shows on apples, figs, and a few others before we release it – we want to have a decent backlog of shows so that we can maintain a pace of one podcast a week.

UNC Charlotte gardens

But enough about me! The current Gardens Professors called my attention to a recent article titled “The effect of ad hominem attacks on the evaluation of claims promoted by scientists”, and I found it informative to say the least. This article provides instructions on how to stop people from trusting a particular study.

No, seriously. If you wanted to you could actually rewrite this as a short manual on how to make people question the results of any scientific study.

And if you did I think it would look kind of like this:

(Short Disclaimer – I’m pretty sure that the authors of the above article never intended it to be taken in the way I’m presenting it. I’m posting this purely as satire.)

So, someone has published a scientific article that you disagree with. Hey, we’ve all been there. Scientific evidence that contradicts your beliefs/works/preconceived notions sucks, but it isn’t the end of the world. There are things you can do.

You might consider conducting your own well-designed experiments that would call into question some of the claims of the offending work. Once upon a time this was been the standard way to address this kind of problem, but this could take months or even years to accomplish. And the truth of the matter is that your experiment might not even say what you want it to and even if it does, with attention spans the way they are, nobody will even remember what you’re even talking about when your paper comes out.

Which is to say, there are better, faster ways to take care of inconvenient research, and that’s where this convenient manual comes into play.

Rain gardens at UNC Charlotte

First, realize that attacking the research itself isn’t a sure thing. Sure, it’s the right thing to do, but morals be damned, attacking the research itself can be waaaayyy too technical. People won’t understand what you’re talking about, so forget about it.

Attacking researchers personally by making nasty comments about where they graduated from college or that they do sloppy research would seem like winner, that kind of attack just doesn’t cut it today. Maybe it’s the political climate, but, to their credit, people just aren’t responding to non-specific personal attacks the way they once did.

So you’ve got to be smart and hit them where it hurts. You could say that data was fabricated in the paper that you want to discredit, but this could be problematic if it isn’t true. Not to worry. All you really need to do is find an instance where the researcher did do something wrong. In fact, it’s possible that some past misconduct could be even more effective at discrediting a paper than misconduct on the paper in question itself.

The gold standard, however, is conflict of interest. By establishing that the researcher who has caused you grief has some sort of conflict of interest you can cause people to question the results of research just about as effectively as if some sort of misconduct had taken place, and conflicts of interest are much easier to find! You could blame a company, a person, or even a University. Shoot, want to show that a study, which demonstrates that an herbicide is effective at controlling a weed, isn’t true? All you need to do is show that the company which makes the herbicide gave a few hundred dollars to an athletic program at the school, or show that one of the student workers in the lab has a second cousin employed by the company. It’s all good.

Water hyacinth

And so there you have it. The fast, easy way to discredit someone. And remember, just implying things can be as effective as having facts. No need to lie! Good Luck, and remember The Truth is What You Make It!


Image courtesy of Plant & Soil Sciences eLibraryPRO at UNL

I was asked by Dr. Linda Chalker-Scott to look up some information in order to answer a recent comment and question on a previous post.

Paraphrased, the question is, “… are there any verifiable “organic” fertilizers that can be guaranteed to be made from 100 percent non-GMO sources.”

First off, let me state up front that the whole “Non-GMO” labeling effort is pure marketing. There is no evidence to suggest products that come from genetically engineered crops are any different than crops made from other plant breeding methods. The body of evidence in fact suggests they are as safe as their conventional counterparts, and have some excellent benefits to farmers and consumers from an economic and environmental standpoint.

Having gotten that disclosure out of the way, and assuming that price is not a factor, it turned out to be an interesting question to answer.

“USDA Certified Organic” fertilizers would be problematic, since there are exceptions to the organic standards, which allow manures fed GE crops to be used.

Similarly, oilseed meals like cottonseed, soybean meal, etc. also can be certified organic, even though they come from genetically engineered crops.


Alfalfa Field image courtesy of Wikimedia Commons

One possible alternative in that category is alfalfa meal, since genetically engineered alfalfa is currently grown on only 13.5% of alfalfa acreage, whereas in the case of cottonseed, soybean, sugar beet, and corn products, the rate of adoption of genetically engineered crops is well over 90% of U.S. acreage.

Only about 13.5 percent of harvested U.S. alfalfa acreage is genetically modified, compared to more than 90 percent of corn, soybeans, cotton, canola and sugar beets acres, according to a new USDA report that cites 2013 farmer surveys.

It appears likely the percentage of genetically engineered alfalfa will continue rising, though: Roughly one-third of newly seeded acreage planted that year was of a biotech variety resistant to glyphosate herbicides, USDA said.

Farmers have been slower to adopt genetically engineered alfalfa partly because it’s a perennial crop that stays in the ground for roughly five years, said Dan Putnam, an alfalfa extension specialist at the University of California-Davis.

It would be incumbent upon the buyer to ask, however, if the alfalfa meal came from a grower who does not use genetically engineered alfalfa, and whether or not the supplier of the alfalfa meal guarantees that.


Manure, a field in Randers in Denmark. Image courtesy of Malene Thyssen at Wikimedia Commons

“Demeter USA” … the private certifying entity that guarantees “Biodyamic” preparations does require that any manures come from livestock fed only “USDA Certified Organic” feed. So manures that carry that seal should satisfy the question.

As an aside, here is Dr. Linda Chalker-Scott’s literature review of “Biodynamics” and why that certification has little science to recommend it.

Further, finding the product would be difficult, since it is primarily produced on-site at certified Biodyamic farms, and used there.


An underwater shot of a kelp forest. Image courtesy of Wikimedia Commons

Next products that might qualify are seaweed, or kelp products. There are no genetically engineered seaweed/kelp products I’m aware of. However, there are real concerns about the sustainability of harvesting seaweed and kelp from the wild.

Dr. Linda Chalker-Scott wrote about them here:

The ecological impacts of increased seaweed harvesting are currently under investigation and the possibility of significant ecosystem damage is real.

There is however, some interesting research and startup companies that are farming seaweed and kelp for a variety of potential uses.

I can’t however, find any products available for the home gardener that are sourced from this effort. Still early.

So, when it comes to seaweed/kelp products, you’ll have to (again) ask a reputable supplier to answer the “sustainable” question.


Bat Cave Mine Image courtesy of Wikimedia Commons

In a similar vein, “Bat guano” products would also qualify as “non-genetically engineered”, but the sustainability question also comes into play. How is it harvested? 

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?


Non edible fish scrap processing … Public Domain image from 1894

Fertilizers made from by-products of the seafood and fish industries, assuming they don’t come from aquaculture farms, since the livestock feed for those operations could be sourced from genetically engineered crops, do have a history.

Two links (there may be others, but these seem sufficient for now), a comprehensive review of products (including fertilizers) from the Alaska seafood industry, put together by Oregon State University

Fish Fertilizer Product Descriptions

Fertilizers are characterized by their Nitrogen-Phosphorous-Potassium content (N-P-K). Therefore all fish material will have some fertilizer value since fish contain protein which is Nitrogen,
the bone contains Phosphorous and the flesh and bone contain Potassium. Generally, fish products are re-allocated to fertilizer use for any number of reasons including quality too poor for feeding, volume too small to convert to fishmeal and oil, and an available agricultural market in the vicinity of the waste material.

And a similar document put together by Michigan State University about the use of fish by-products for other uses.

In an effort to help the Michigan fish processing industry find better solutions to handle fish processing waste materials, a project was initiated to determine the viability of composting fish waste.


Mined Sodium Nitrate (NaNO3) Image courtesy of Wikimedia commons

There is a mineral product called Chilean Nitrate or Nitrate of Soda that is mined from a desert in northern Chile that is allowable for use under the standards for organic production in the U.S. However, it is not allowed for use under Canadian, or international organic standards, and a change to prevent its use under U.S. standards is still pending. Up until 2012, this was the wording for its use.

Sodium nitrate, also known as chilean nitrate, cannot account for more than 20 percent of the N requirements of organic crops in the United States.

Its use is also prohibited by the International Federation of Organic Agriculture Movements (IFOAM) and most other standards for organic production outside the United States.

After 2012, the 20% restriction was dropped in the U.S.

The expiration of the current notation will effectively mean that sodium nitrate may be used in organic crop production without a specific restriction on the amount used: however, producers must continue to comply with all requirements of the soil fertility and crop nutrient management practice standard.

Although the National Organic Standards Board (NOSB) recommended that sodium nitrate become a completely prohibited nonsynthetic substance, the NOP has not issued rule-making to carry out this recommendation as of yet.


A by-product of the poultry industry.  Is it from poultry fed only non-GMO feed?


The final piece of the puzzle can be found (only partly in jest) in Dr. Jeff Gillman’s post about a cheap, locally available source of Nitrogen.

You’d be saving yourself the cost of fertilizer, saving the environmental cost of shipping the fertilizer you might otherwise purchase, saving water, and you’d have something unique to tell your gardening friends about.  Win – win situation as far as I’m concerned.

In summary, I don’t buy into any of the fear-based marketing of products that come from genetic engineering. There may be (at this time) sources of alfalfa meal that do not come from genetically engineered sources.

Biodynamic manures certified by Demeter USA require that the animals be fed only “USDA Certified Organic” feed, but will be difficult to come by. Seaweed/Kelp and Bat guano products would qualify, but have major sustainability questions about them. Lots of potential with seafood/fish by products, and finally … a personal possible solution.

Many thanks to Emanuel Farrow, a consultant to both conventional and organic farmers, who helped point me in the right direction and provided important fact checking expertise for this post.

Our New Year’s Resolution – to keep you informed and entertained every week.

Happy New Year!

The Garden Professor’s collective resolution is to have at least one new blog post a week for 2018. So I’m kicking things off with a little fact checking on the claims made for a product that’s “a complete ecosystem in a bottle.” The company touts its strong connection to science (“our products revolve around biology”). There is a long list of ingredients and claims – way too much for one post. We’ll start with the first four this week.

All this can be yours if the price is right!

Ingredient claim #1: “Chitin/chitin degrading Bacillus: Chitin is a natural polymer that is found in crustaceans, such as crabs, lobsters, shrimp and oysters as well as other organisms, such as insects, worms and fungi. When added to the soil ecosystem, chitin (also referred to as chitosan) promotes the growth of chitin-degrading bacteria. These bacteria, in turn, create a hostile environment for pathogenic fungi and parasitic nematodes. Chitin also acts directly on plants to promote tissue repair and disease resistance.”

Fact check #1: A couple of technical points: oysters don’t have chitin. And they’re not crustaceans. They are MOLLUSKS. They have shells with CALCIUM. And chitosan is not the same thing as chitin. It’s an industrially produced material that comes from chitin.

Not a crustacean.

Chitin is indeed found in arthropods, which include crustaceans and insects. Now, most of us don’t have crabs, lobsters and shrimp roaming our landscape, but we do have insects. Lots of them. They produce a lot of chitin when they molt and when they die. Do you really think we need to add more chitin for Bacillus to consumer? I sure haven’t seen any science supporting that practice.

What about the Bacillus species that degrade chitin? Well, if you’ve got insects in your landscape, you can bet you’ve got microbes that break down chitin as well. Otherwise you’d be up to your garden boots in chitin carcasses. So why do we need to add more bacteria?

Imagine billions of these in your garden…

Finally, there’s no evidence that chitin applied to plants in the landscape has any effect whatsoever. You might get responses in the lab, and chitosan (not chitin) might have some direct application. But like many other elicitors, you have to get it inside the plant to have a cellular effect. And plants are particularly adept at keeping things like decomposing bug bits outside of their tissues.

Ingredient claim #2: “Compost tea: The disease suppressive characteristics of compost have long been known and therefore the liquid extracts from compost, known as compost teas are being use to battle plant disease while stimulating plant growth. Beneficial organisms including bacteria (primarily from the genera Bacillus, Pseudomonas, and Penicillium) along with some yeast and fungi form a physical barrier against disease causing agents and provide a competitive environment in which the pathogenic species lose out. In addition, compost teas stimulate plant growth, translating into a healthier plant, which is more resistant to attack from disease. Compost teas have shown effectiveness in the control of late blight, grey mold, downy and powdery mildew, fusarium wilt, and apple scab among many others.”

The visuals are more interesting than the product.

Fact check #2. Just because compost has disease suppressing characteristics doesn’t mean that water leaching through it will have the same. We’ve been hearing for years that compost tea suppresses disease. Where’s the definitive research? It’s a topic I’ve been following for nearly two decades and there’s still nothing that’s consistently effective. (Another technical point here: it’s illegal to make pesticidal claims of a product that’s not registered for that use. Company lawyers may want to review that.)

There are many species of bacteria, including the ones mentioned, that form protective and beneficial biofilms on plant tissues such as fine roots. You can find these bacteria in compost and other sources of organic material – that’s their food source. You won’t find many of them in compost tea.

I’d love to see evidence of anything stimulating plant growth other than plant growth regulators (or hormones as they’re sometimes called).

Aren’t marketers getting tired of compost teas yet? I’m getting tired of hearing about them. I reviewed the science about them 10 years ago and haven’t seen anything to warrant an update.

Ingredient claim #3: “Essential oils: or essences they are called, are highly concentrated substances extracted from various parts of aromatic plants and trees. Essential oils are combined with other carrier oils and teas for stabilization. Essential oils are used against plant pests and disease by interfering with their reproduction and feeding habits while protecting beneficial predatory organisms.”

We like them, ergo they work.

Fact check #3: Essential oils have no documented benefit when applied outdoors. They can be effective in closed spaces, like homes and greenhouses, but they dissipate quickly outside. What I really want to see, however, is the mechanism by which oils can identify – and actually protect! – beneficial insects while killing pests. (Hey, lawyers…we’ve got another pesticidal claim here…)

Ingredient claim #4: “Streptomyces griseoviridis: Is a naturally occurring soil bacteria. The microbe deprives pathogenic fungi of living space and nourishment by colonizing roots in advance of fungi. In addition the microbe secretes various enzymes and metabolites which inhibit pathogenic growth. Streptomyces griseoviridis has been shown to promote the growth and yield of all plants. Streptomyces griseoviridis is used for the prevention of root and stem rot, Pythium, Rhizoctonia, Helminthosporium, Sclerotinia, among others.”

All those stickers keep the bad guys from colonizing.

Fact check #4: While this is a naturally occurring soil bacterium, it’s not clear where it naturally occurs. EPA information states it was first isolated in Finland from peat bogs. Is this something we should be introducing to our own soils? Its effectiveness in disease control and plant performance is sporadic and confined primarily to greenhouse application on crop plants. The diseases listed are common in greenhouses, but not necessarily in gardens and landscapes (presumably because there are natural controls outdoors in healthy soils). There is certainly nothing to support its use in gardens and landscapes, especially considering that many native, beneficial bacterial species can colonize plant roots and act as a protective biofilm.

Stay tuned for next time!

Dowsing for dollars

Recently I was at the Northwest Flower and Garden show and spoke to a gardener who was excited about some new information from his garden club meeting. Their speaker was a dowser – who promotes dowse gardening.

Traditional dowsing for water

Now this was a new concept for me. I’ve heard of dowsing, of course, in the context of finding underground water. But dowse gardening?

Fortunately, my gardening friend shared his handout with me. I did a little Internet sleuthing and found the author, whose goal was to combine her two interests: dowsing and gardening. In a 2003 column, she stated “My main focus is ways of using subtle energy to get good crops or gardens.”

For me, this was an immediate red flag. It’s very much like the author’s motivation in The Sound of Music and Plants. Searching for a topic for an undergraduate research topic, she asked “What in the world can I do with music and plants?” Trying to force two unrelated subjects together without preliminary data to suggest the pairing is not a logical approach to scientific inquiry.

Anyway. Back to dowse gardening. It would take me weeks to dissect all of the claims made in the handout. In brief, the presentation explains how to find energy, how to receive and broadcast energy, and how to use “subtle energy” to grow healthier plants and control pests.

This circle garden just looks sad and lonely.

Unfortunately, the specifics on exactly how this happens were not given. But attendees were advised to create circle gardens (they are energy outgoing), to use earth energies to determine where and where not to grow plants, and to use prayers and crystals to improve seed sprouting. At least in this last case there were data:

“Prayers over seeds -30% increase in sprouting and production – energy! Next step – crystals pointed at sprouting seeds, 50% increase in sprouting and production – energy!”

And finally, there were all kinds of products that were recommended, including

  • French coils for “inducing beneficial energies in trees and larger perennials”
  • Energized water made by a process “that can transform our banal tap water back to its natural potent state as the elixir of life”
  • Sonic Bloom – an “organic fertilizer applied with sound”
  • Slim Spurling’s Light Life Tools which “support the work of environmental clearing, air pollution clearing, energy balancing, water improvement, alternative agriculture methods, insect control without sprays, beneficial insect enhancement, alternative health methods, personal self-care, computer radiation reduction, EMF pollution reduction, personal life improvement as well as business improvement”
  • Intrinsic Data Field Analyzer – “a consciousness interactive instrument that has been used experimentally to detect and balance the IDFs of plants, animals, minerals, and virtually all animate and inanimate objects”
What you’ll need to detect subtle energy

As a scientist, it’s easy for me to discount all of this as silliness. But the fact remains that many people, including gardeners, long for mystical approaches to life. And unfortunately there are always going to be hucksters waiting to take advantage of that longing.

Buzz words are not evidence


I made this little image to try and make a point, not about Bt or GMOs or organic agriculture (all important topics for another day), but about the use of buzz words. I’m tired of the way words like “chemical” and “natural” get thrown around to try and make things sound bad or good. Neither of them are particularly useful terms because the definition of chemical is so broad as to cover just about anything, and “Natural” is more-or-less meaningless and entirely subjective.

So, my simple plea is to not let emotionally loaded buzz words sway you, but dig into the actual research and evidence to make decisions about what you think is good or bad.

Joseph Tychonievich

Not raking leaves: Too good to be true?

Rejoice, gardeners and homeowners, for your deliverance from the drudgery of raking leaves has arrived. Or so goes the proclamation from a viral article that popped up on social media this past fall.

The article in question was posted on the Woman’s Day magazine website based on information from the National Wildlife Federation As the article points out, leaving piles of leaves on the lawn are good “habitat” and homeowners should just let the leaves fall where they may for the sake of supporting critters in the lawn. Of course, you can always believe everything you see online, right?  Let’s take a look at what research can tell us.

Not so fast. There are a few issues with this new proclamation. Not that I am a great fan of the rites of autumn that dictate that we remove leaves from the lawn. It is one of my least favorite garden tasks, as evidenced by the fact that I wait until every last leaf has fallen before I get the leaf blower out so I’m certain that I don’t have to do it more than once.

Many people rake up leaves in the lawn because of aesthetics — we don’t want our neighbors to see a messy lawn. But there are lots of other issues that leaving leaves on the lawn can cause. Let’s take a look at all the reasons why leaving a layer of leaves on the lawn may not be the best idea.

First, the claim that leaving leaves where the fall on the lawn provides “habitat” for wildlife. What wildlife? The original source suggests small mammals, butterflies, and moths — specifically providing a place for overwintering. While I’m sure that there are some perfectly nice little critters that will make their home in the leaf litter, I have a name for what a lot of those things that find their home in your new “habitat” may be— pests.

Plant debris provides excellent overwintering opportunities for many garden pests. I also suspect that some of the wildlife that would find a comfy abode in the leaf litter would be small rodents, like mice and voles, that would enjoy nothing more than to snack upon some of the woody plants in your landscape. I also found some research that says removing leaf litter from residential areas reduces populations of ticks (article). Definitely something I wouldn’t want to welcome with open arms to my lawn.

Now let’s think about how plants make their food — they use sunlight for the process of photosynthesis. The article in question advocates letting leaves pile up where they fall on the lawn.  This means piling up on the grass (or in my case, whatever passes for green).  A layer of leaves on top of the grass will inhibit the plants from making their own food. While grass may not be actively growing in the winter, as long as it is green, it can still perform photosynthesis and store the food for spring. Even if you have a species of grass that turns brown in the winter, a pile of leaves would become an issue when things warm up in the spring.

It also turns out that a thick layer of matted leaves on top of the soil can create a barrier that reduces oxygen in the soil — thus creating an anoxic condition that will reduce or damage roots. Not only do the leaves create a barrier, but research has shown that the rapid consumption of oxygen by leaf litter bacteria lead to anaerobic conditions in the leaf litter itself (article).

Give the reduction in sunlight and soil oxygen, grass can have a difficult time thriving in areas of heavy leaf litter. Some other research results I found indicate a layer of leaf litter reduces the amount of herbaceous plants (in woodland) (in a field study). If you think about it, you don’t see many small herbaceous understory plants in forests with lots of trees — it isn’t just the shade from the trees that causes a problem.

I’ll also point out that for dog owners, leaving a layer in the yard can make it much easier to fall prey to what we refer to as “yard bombs.” I’m sure other dog owners have felt this pain.

Now, I’ll be the first to tell you that leaves are a valuable resource for lawn and gardener, so don’t think that I’m anti-leaf. I put all of the leaves that fall in my yard to work for me. While leaving the leaves to pile up into layers on the lawn is not a good idea, using a mower to chip them up and leave them in place will provide valuable organic matter and nutrients for the soil. So if you don’t want to rake them up, run over them with the lawnmower so they will break down quickly into the soil (and don’t smother out the grass).

If you do rake up (or vacuum up) the leaves, there are a few things you can do with them. First, the shredded leaves make a good winter mulch for landscape beds (put the plant suppressing power to work controlling weeds). You can also bag them up and store them for use in composting next spring and summer when you have fresh green plants to add to them.

This article originally appeared in the Charleston Gazette-Mail on November 15 (sans citations).  

You can find my other articles online at wvgardenguru.com


The “safe seed pledge” is meaningless

The seed catalogs have started showing up in the mail, and a great number of them include something like this on the first few pages:


Here’s the thing: NO ONE is selling genetically engineered seeds to home gardeners. There is one company, funded by kickstarter, that is trying to sell genetically engineered seeds of a glow-in-the-dark plant sometime in the future (though, like a lot of kickstarter project, the actual release date keeps getting delayed) but other than that, genetically engineered varieties are only being sold to commercial farmers, and only after the farmer has signed a pretty comprehensive licensing agreement.

You can go to the store and buy food made from genetically engineered varieties — essentially anything that contains corn and isn’t labeled as organic will be — and you can stop by the pet store and pick yourself up a fish with jellyfish genes, but no one is trying to sell you genetically engineered seeds.

So those pledges in seed catalogs promising they contain no GMO seeds are technically true, but also pretty meaningless. So if you are worried about accidentally getting a GMO variety, don’t be. And if you wish you COULD grow one, sorry, you are out of luck, unless that kickstarter project ever actually gets up and running.

— Joseph Tychonievich