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.)
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.
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.
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.
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!
One of my favorite topics back when I taught Botany 101 was plant oddities. A recent question on our Garden Professors’ discussion group on Facebook reminded me about cladophylls, like the one pictured below.
Cladophyll literally means “branch leaf.” Anatomically it’s a branch (it has nodes from which new stems, leaves, flowers, and even roots can arise), but it functions as a leaf. It’s the main site of photosynthesis in plants such as holiday cacti (Schlumbergera species). Like other cacti, they have reduced leaves and if you look closely at the photo, you can see the leaves as tiny hairs arising from the nodes at the end of the stem and along the sides.
But unlike cacti, these plants aren’t found in deserts, and their leaves are soft threads rather than the vicious sharp spines you’ll find in typical cacti. Instead, these are generally epiphytes in coastal mountains where humidity is relatively high. But root water is limited for epiphytes and these waxy cladophylls probably are adaptations against water loss. Their reduced leaves are immune to drought stress, unlike those of other succulents which appear only when water is plentiful.
As you might expect from their red, tubular flowers, holiday cacti are pollinated by hummingbirds in their native environment. Gardeners who have a sufficiently mild climate to grow these outdoors might be lucky enough to see them visited.
It’s been awhile since I wrote about, or recommended a blog I like which I often use as a source of something to share to The Garden Professors Facebook Page, so I thought I’d revisit the topic this month.
Add a friend, chef Michelle Fuerst, to provide recipes and there you have it.
Our goal is three-fold: to share the fascinating biology of our food plants, to teach biology using edible, familiar examples, and to suggest delicious ways to bring the plants and their stories to your table. To judge by the questions we are often asked at dinner parties (“What is an artichoke?” “Why is okra slimy?”), some curious eaters genuinely want to know which plant part they are eating and how its identity affects the characteristics of the food.
Plants and food? Tell me more! Well, espousing the view that ‘a person can learn a lot about plants through the everyday acts of slicing and eating them’, The Botanist in the Kitchen ‘is devoted to exploring food plants in all their beautiful detail as plants – as living organisms with their own evolutionary history and ecological interactions’.
I first learned about the blog back in 2015 from an article in Business Insider, linking to their post on the various foods we grow, that were bred from one species of plant …
Six vegetables you can find in any grocery store and which most people eat on a regular basis are actually all from this one plant. Over the last few thousand years, farmers have bred Brassica Oleracea into six “cultivars” that eventually became many of the vegetables we eat …
Some species have undergone the domestication process multiple times, and with some of these species, each domestication effort has focused on amplifying different structures of the plant, producing a cornucopia of extraordinarily different vegetables or fruits from the same wild progenitor. Such is the case with Brassica oleracea. The wild plant is a weedy little herb that prefers to grow on limestone outcroppings all around the coastal Mediterranean region.
So if you enjoy learning about plants we eat, and trying various recipes with them, be sure to follow the Botanist in the Kitchen via email.
Previous posts here on the other blogs I’ve recommended:
As we edge closer to spring it is time to start getting ready for the active growing season. Many gardeners kick off their gardening year early with indoor seed starting to prepare for the upcoming season.
Starting your own seeds is an excellent, and often economical way to prepare for your year of gardening. Whether you grow vegetables or flowers (or both), starting from seeds can offer many benefits. Of course, there are some dos and don’ts for getting the most mileage from your seed starting endeavors.
I recently connected with Joe Lamp’l, host of the Growing a Greener World show on public television and the more recent The Joe Gardener Show podcast to talk about advanced seed starting techniques and technology.
You can follow the link below to listen to the show on your computer, or find it on Stitcher or iTunes (links included on the show page, too). In addition to the podcast, the show page features extension notes on everything we chatted about with links to good reading materials.
Be economical. One of the great benefits of starting plants from seeds is saving money. A packet of several (even hundreds) of seeds is often around the same price you’ll pay for one plant at the garden center. Of course, if you go out and splurge on the fancy (and expensive) seed-starting systems you see in your garden store or favorite catalog you may end up investing more than you planned. Instead of fancy seed starting trays or peat pellets and pots, use low-cost or recycled items such as takeout containers or shallow disposable aluminum baking pans to start your plants. Remember that if you are reusing containers, especially ones that have had plants grown in them before, that sterilization is key in reducing disease. Thoroughly wash the containers, then dip in a solution of 10% household bleach (1 part bleach : 9 parts water) to disinfect. There are some horticultural disinfectants out there, but bleach is usually the easiest for home gardeners to get since you can pick it up at the local store.
Start seeds in clean, sterile seed-starting mix. This is one area where I don’t skimp. You’ll want to use a sterile mix that is primarily made of peat or coconut coir. It is lightweight and pathogen free and also low in fertility, so you will be less likely to lose plants to such issues as damping off (a fungus that rots the seedlings off at the base). Using regular potting mix may work, but increases your chances of such issues. Plus, seeds are equipped with enough nutrients to make it to their first set of true leaves before they need anything from the soil. I know that some sources say to use mixes with compost in them, but unless you know 100% that the compost got hot enough to kill all pathogens (140 degrees plus for several days) you could be introducing diseases to your plants that could affect them in the seedling stage or in the future.
Once the seedling has its first set of true leaves (the second leaves that appear), you should transfer it to an individual container/cell/pot with regular potting soil. At this point, the plant will need to have nutrients from the soil to grow healthy. You’ll want to loosen the plant from the seedling mix (I use a chopstick) and lift it by the leaves (not the stem). Temperature control is key.
Heat is usually the most important factor in coaxing your seeds to germinate, so placing your newly sown seeds in a warm (around 75 degrees F) place will help them germinate faster. Fast germination is key for making sure you get the optimal number of seeds sprouting. However, moving the seedlings to a cooler place (around 65 degrees) after they’re germinated will make them grow sturdier and keep them from getting thin and leggy. Most people laugh when I tell them, but one great warm place to start seeds is on top of the refrigerator.
Light is necessary for good plant growth. Most seeds don’t require light until they get their first true leaves, but after that you’ll want light to keep your plant healthy. Some people are lucky to have a good, sunny (usually south facing) window with plenty of light. Otherwise you’ll need to invest in some lighting. The most economical option is a basic shop light fixture from the hardware store. You can buy plant lights, or full spectrum lamps for it, but if they prove too difficult (or expensive) to find, use a regular warm fluorescent and cool fluorescent bulb to get the right light spectra. You’ll want light on for about 16 hours per day. If you are using a window, be sure to turn the plants regularly to keep them from
growing in one direction. As LED lights become less expensive, many home gardeners are checking them out for home seed starting. You can use a full spectrum white LED bank, but plants primarily use red and blue light so you can also find high-intensity LED banks for plant production that are blue and red (makes purple!). Some research is emerging that a tiny bit of green light helps growth, so some newer systems are incorporating a touch of green, too.
Don’t get started too early. Look at the packet for the number of days/weeks before last frost to start your seeds. If you start them too early, you could end up with spindly, leggy plants or ones that have grown too large for their containers. Even if you have good lighting, your plants will not thrive being cooped up in the house too long.
What about fertilizer? Up until the first set of true leaves, seedlings don’t need much in the way of fertility. When they’re put in larger containers or cells, a good potting mix (usually containing some type of fertilizer or nutrients) will get you most everything you need….to a point. If you’re growing in small containers, say those cell packs where you have very limited soil, you may find that you need to provide supplemental fertility after a few weeks. There’s only so many nutrients in that potting mix in small amounts, so if you are holding your plants for longer than, say, six weeks you may need to apply a water-soluble fertilizer or start off with a slow-release fertilizer. Larger containers, say a 3 or 4 inch pot, may have enough soil to have sufficient nutrients to get you to the point of transplanting.
This month’s National Geographic has a brief article from an ongoing study of the DNA profiles of urban honey. While we can all observe honeybees visiting flowers in our own gardens, until recently we could only assume what nectar they were collecting for honey production. This tantalizing snippet completely blew me away.
The study, undertaken by an entomologist who founded the Urban Beekeeping Laboratory and Bee Sanctuary, is sampling urban hives from major cities, including Boston, Portland (OR), New York, San Francisco, Seattle, and Washington DC. For each of these cities, National Geographic reports the top three plants for honeybees based on relative DNA levels.
Here’s what I found amazing about this research:
The top sugar sources are from TREES. Not wildflowers. We don’t see bees visiting trees as easily as we see them visiting flowers, so our perceptions are biased. Over 75% of the sugar used for urban honey is from trees.
The trees that are most popular for bee visitation are not necessarily native to those regions. Seattle bees, for instance, prefer linden and cypress trees, neither of which are part of the native coniferous forest. Likewise, the despised eucalyptus trees of San Francisco are one of the top three sugar sources.
You’ll notice that I didn’t use the word “nectar” in describing what bees are collecting. That’s because much of the sugar they are gleaning isn’t coming from flowers. It’s coming from sap-sucking insects like aphids that produce honeydew. Bees apparently collect honeydew as well as floral nectar.
Urban areas usually have higher plant diversity than rural areas, given the variety of woody and herbaceous plants that people use in their gardens and landscapes. The researchers speculate that this higher plant diversity may be one reason that urban hives are healthier and more productive than rural ones.
Many gardeners operate under the assumption that native plants are the best choice for gardens and landscapes. Though certain landscapes (like those undergoing ecological restoration) should only be planted with natives, there is no evidence-based reason that we shouldn’t be using non-invasive, introduced species as part of our planting palette. In fact, research has demonstrated that tree species nativity plays only a minor role in urban landscape biodiversity: most animals learn to use new resources in their environment. Honeybees, considered to be “super-generalists” insects, are demonstrating that in spades.
Greetings all, and good to be back in the saddle for the Garden Professors. It’s been a while since I’ve filled you in on my own personal gardening struggles (lots) and triumphs (few) as well as topics I think you’d be interested in. I’ve always appreciated the kind comments and good questions our readers pose, in response to my off-kilter posts and horrific punctuation.
I’m sure there is one BURNING question that long-time readers have:
I’m sure many readers have been at the receiving end of a cactus spine or Agave poke; the genus Puya makes Agaves look like stuffed animals. Fish hooks line the margins of each leaf, and cascade over the side of the pot. Therein lies the problem…
I’ve attempted to “go in” a couple of times, but even leather grilling gloves get snagged. Need really strong tongs (two sets?). I’m probably going to have to just bust the pot. She didn’t make it out to the deck this summer due to the awkward pot situation. Suggestions welcome, especially from anyone who has wrestled with one of these (and lived)!
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.
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
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
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.
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.