Advancing the science of gardening and other stuff since 2009
Author: Linda Chalker-Scott
Dr. Linda Chalker-Scott has a Ph.D. in Horticulture from Oregon State University and is an ISA certified arborist and an ASCA consulting arborist. She is WSU’s Extension Urban Horticulturist and a Professor in the Department of Horticulture, and holds two affiliate associate professor positions at University of Washington. She conducts research in applied plant and soil sciences, publishing the results in scientific articles and university Extension fact sheets.
Linda also is the award-winning author of five books: the horticultural myth-busting The Informed Gardener (2008) and The Informed Gardener Blooms Again (2010) from the University of Washington Press and Sustainable Landscapes and Gardens: Good Science – Practical Application (2009) from GFG Publishing, Inc., and How Plants Work: The Science Behind the Amazing Things Plants Do from Timber Press (2015). Her latest effort is an update of Art Kruckeberg’s Gardening with Native Plants of the Pacific Northwest from UW Press (2019).
In 2018 Linda was featured in a video series – The Science of Gardening – produced by The Great Courses. She also is one of the Garden Professors – a group of academic colleagues who educate and entertain through their blog and Facebook pages. Linda’s contribution to gardeners was recognized in 2017 by the Association for Garden Communicators as the first recipient of their Cynthia Westcott Scientific Writing Award.
"The Garden Professors" Facebook page - www.facebook.com/TheGardenProfessors
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Books: http://www.sustainablelandscapesandgardens.com
This weekend I received a link to a Maryland gardening column with the intriguing title “Murder by Mulch.” My correspondent was concerned that her planned use of arborist wood chip mulch was going to cause problems. I assured her that it would not – but then spent some time looking at the column and putting it through CRAP analysis (credibility, relevance, accuracy, and purpose). It’s a skill that I encourage everyone – not just gardeners – to develop. (You’ll need to read the linked column to understand the context of my comments below.)
So we’ll start with credibility. The column is not a peer-reviewed resource, but then again neither is this blog. The author is a retired Extension specialist with research publications in compost science. That would seem to fit well with the topic. We’ll give it the benefit of doubt for now.
Use of arborist wood chips in a home landscape
How about relevance? Is this information relevant to the use of mulches in home landscapes? Absolutely.
Is this accurate information? At this point the column starts to fall apart. Let’s start with the photo (you’ll need to go to the linked column to see it). This tree didn’t die because of mulch, but because it had girdling roots – the result of planting trees improperly. Furthermore, there is no mechanism I can think of in which mulch would “strangle” a tree.
Another victim of girdling roots
Next, there is no distinction made among different types of mulch. Bark is not the same as wood chips, and coarse materials function differently than fine mulches. Bark mulches don’t absorb water like wood chips do, and fine mulches inhibit air and water movement into the soil (coarse mulches don’t cause this problem).
Wood chip mulches are an excellent choice for weed control and woody plant establishment
Finally, there is the statement that repeated application of bark will raise soil pH and increase manganese levels. There is no research I could find to support either one of these claims.
The purpose of this column was to educate – but it has failed to do so for the reasons outlined above. Where did the CRAP analysis fall apart?
We need to go back to looking at the author’s credentials. It’s not apparent from his publication record that he’s researched mulches at all. His work was primarily on composts, with the most recent article published in 1998. Nor has he published articles relevant to management of woody plants.
Wood chip research
Urban horticulture and arboriculture are relatively new fields of study that are rapidly evolving. Information once accepted as factual decades ago may no longer hold true, as newer research changes our understanding of the way that plants and soils work in managed landscapes.
By Visiting Professors Dr. Charlie Rohwer and Ulrike Carlson
I’ve had this dream of doing a full academic etymological study of oranges, with the help of a second-cousin-by-marriage linguist and her historian husband. Being honest with myself, I know that’ll never happen. And also, honestly, they’d have to do all the work anyway.
But, the Garden Professor’s Facebook post about the citrus family tree revived my interest. Not for a full-blown academic analysis of the word ‘orange,’ but for a blog-friendly, factual, interesting post. So I got my linguist cousin Ulrike Carlson to edit for accuracy too.
The name given to the orange by Linnaeus was Citrus aurantium, and the only other citrus species he noted in his first volume of Species Plantarum was Citrus medica. The current taxonomy of citron is Citrus medica L., and bitter orange (or Seville orange, used for marmalade and Belgian beer) is Citrus aurantium L. According to Linnaeus, sweet orange and pomelo were separate varieties of C. aurantium (var. sinensis and var. grandis, respectively). For a pretty image of the family tree, see the National Geographic article here. Basically, it is now known that all common citrus fruits are hybrids derived from citron, mandarin, pomelo, and papeda.
The current taxonomy for sweet orange, Citrus sinensis (L.) Osbeck, clearly defines the fruit’s Eastern origin (sinensis comes from Latin for ‘Chinese’) and altered nomenclature (Osbeck refined Linnaeus’ original taxonomy). But the name given to bitter orange, C. aurantium, points to its South Asian origin, and here’s why. The Tamil (south India) word for orange transliterates to ārañcu; Sanskrit words look similar; the Persian nārang is derived from there. As the bitter and sweet orange hybrids were likely made somewhere between Northern India and Southern China, it would be expected that the European names for these fruits come from these or nearby areas too. The origin of Linnaeus’ aurantium are obvious. Aurantium is Latin for the orange tree, and aurancia is the fruit. If you say these words aloud, they all sound similar to each other, to nārang, and to the English orange.
But here’s where it gets more interesting, with a preface: the word apple has historically been used to describe any fruit that’s not a small berry. Also, bitter oranges were common in Europe before sweet oranges. In fact, when sweet oranges came on the scene in the 17th century, wealthy people built greenhouses or gardens (“orangeries”) specifically for the new, more delicious versions of the fruit.
Orangery at the Château_de_Versailles
By Djampa – Own work
My first time in the Netherlands, I noticed orange juice is called sinaasapelsap. I don’t know Dutch really, but…doesn’t that mean ‘Chinese apple juice?’ Sinaas: Chinese (sinensis); apel: apple; sap: …sap (juice)? I knew in French that it’s jus d’orange (juice of the orange), and I knew ‘orange’ in Spanish is naranja (looks & sounds a lot like orange and narang). Why would the Dutch call it Chinese apple juice? Fast forward a couple years, I’m in Denmark, and what do I see? Appelsinsaft. CHINESE APPLE JUICE…English, Dutch, Danish, they’re all Germanic languages. Shouldn’t the Germanic languages call it orange juice, like I do? Then it hits me. English is the odd duck here. The Germanic languages call orange juice ‘Chinese apple juice’. This reflects the name Linnaeus gave the sweet orange (var. sinensis, or ‘Chinese’). Best I can tell, among Germanic languages, only English, Afrikaans, and Scots gets their word for the sweet orange from the older word for the bitter orange, nārang.
Citrus aurantium By A. Barra – Own work
That’s not the last word on the subject though. You can go to Italy for sweet oranges and get arance, the Czech Republic and get pomeranče (apple-orange), Ireland and get oráistí, Bulgaria and get oranzhev, or Portugal and get laranjas (aka, oranges). All words that come from nārang or aurancia. You can go to Estonia, Finland, Sweden, Norway, and Germany and get some kind of Chinese apples (aka, oranges). But even as most Italians eat arance, you’d instead ask for a partuallu in Sicily. Or you’d eat a portokáli in Greece, portokall in Albania, etc. The Portuguese, with their awesome shipping routes, imported sweet oranges from China, then grew and distributed them through Europe in the 17th century. They were a big improvement over the bitter orange (which would you rather have, marmalade from a bitter orange, or a juicy sweet orange?). So some countries called the sweet orange by the name of the proximal country they were shipped from, Portugal. Bitter oranges (AKA Seville oranges, named from where they were grown) are called pomerans (from apple-orange) in Swedish, Pomeranzen or Bitterorangen in German, pomeransen in Dutch…so it seems that when sweet oranges came to Germanic-speaking countries, the languages kept the word they’d been using for the bitter orange (calling it an orange-apple or bitter orange), and added a different word for the sweet orange, calling it a Chinese apple. This is all complicated because political boundaries have changed a lot in Europe, and languages borrow from each other. So northern Germans might still eat Chinese apples, but southern Germans might eat oranges.
Also, if you’re interested and you’ve made it this far, the color orange is so named because that’s the color of the fruit. It’s not the other way around. It’s a pretty recent color descriptor. That’s why robins, with their orange breasts, are called robin red-breast. There was no word for the color orange when the robin was first described.
Also of great interest is the House of Orange. If you’ve seen a Dutch soccer game, or been to the Netherlands, you’ll know they like the color orange. William I of Orange, basically the founder of the Netherlands, came from a principality called ‘Orange’, now in France, and the Dutch celebrate their royal family with the color of its namesake. BUT, Orange, France was named, a couple thousand years ago (before the fruit came to Europe), after a Celtic water god, Arausio. At the time, this had nothing to do with the fruit or the color. HOWEVER, since the middle ages, the crest of the French city shows orange fruit on a branch, and the crest for the German city of Oranienbaum (orange tree) has, you guessed it, an orange tree. According to Wikipedia, Oranienbaum was named after the Dutch House of Orange.
Coat of arms for the House of Orange
For more about how these languages are related, here’s a ‘simple’ chart.
Here at the Garden Professors we try to focus on sharing the best applied plant and soil science information for gardens and landscapes. But sometimes we get sidetracked by information that is SO bad that we need to share it too. So the purpose of this occasional feature – Worst Gardening Advice – is not to poke fun, but to point out the real hazards to plants, people, and the environment by following scientifically unsound practices.
Without identifying which of my GP colleagues nominated this video, we now present how NOT to fix storm damaged trees.
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.
It’s been over a year since I’ve posted to our blog.
I feel bad about that. But there’s always something else competing for my time, and the blog slipped away from the top of my “to do” list.
No more.
Today the federal government has clamped down on the ability of its scientists to communicate with the public. This is real – and it is frightening.
There’s not much I can do about that edict in my position as a state Extension specialist. But as a state Extension specialist I have a responsibility to translate and transmit information to the public relevant to my discipline. So here’s my offer.
If you are, or if you know, a federal scientist who has information relevant to my discipline (applied plant and soil sciences) that you want the public to see, send it to me. I will post it here, and in our social media, keeping the source anonymous.
Science will NOT be suppressed. Yes, that sounds dramatic, but I don’t think any of my colleagues foresaw what is happening with the new administration. It’s time to act.
Thanks to “The scientist, Photos and The o’jays on Pinterest”
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.
Here in Michigan, spring is coming. Crocuses, snowdrops, and reticulata irises are in full bloom. Hepatica, forsythia, and daffodils will be coming on before long. Soon, garden centers and nurseries will be opening and gardeners driven mad by the long winter will rush out to buy every plant they can find with a flower on it. In the mad feed frenzy for flowers, we gardeners will sadly look over countless beautiful fall-flowering perennials and shrubs simply because they don’t happen to be doing their thing when we are shopping.
And that, my friend, is the tyranny of spring. We Northern gardeners all too often let our spring fever skew our gardens to all spring bloomers, totally ignoring and missing a vast array of gorgeous plants that give color and interest the rest of the year.
So, don’t give in. Try, for example, planting a bottle brush buckeye (Aseculus parviflora) a shrub which will thrill and delight with elegant white sprays of flowers in August when all the spring bloomers are looking tired and sad.
Or plant the lovely Hosta clausa which won’t impress with plain green leaves in the spring, but has a later summer flower display you won’t forget.
So this year, don’t give in to the siren song of spring. Add some late bloomers to the garden. You won’t regret it.
You know the word “rogue” as a noun and adjective, and probably from when Sarah Palin “went rogue” during her time as vice presidental candidate.
But you may not know that it also a verb. That’s the way I use it most often. I rogue plants and I complain — often — about seed producers not doing enough roguing.
To rogue means to weed out inferior or off-type plants. It is a critical part of producing and maintaining seed selections of plants. Whenever you are growing fields of plants for seed production, be it tomatoes or zinnias or corn, you get off types. Chance mutations, seedlings produced from errant grains of pollen from another variety, or just change of the diversity within the population. So one has to rogue — walk through the fields and pull out flowers that are the wrong color, corn plants that aren’t yielding enough, all the unexpected variants to keep the variety true to type.
The annoying thing is that a lot of seed producers cut corners — particularly, it seems, for annual flower seed — and don’t bother. The results can be very frustrating.
The worst are flowers in mixed colors. Maintaining a good mix of multiple colors requires careful roguing to ensure one color — due to greater vigor or just chance — doesn’t come to dominate. Lots of companies just don’t seem to bother.
Last year I bought a packet of Zinnia ‘State Fair’, an old, and wonderful seed strain, which was supposed to come in the full mix of zinnia flower colors.
I got pink. That’s all. Just pink. My whole row was pink. Not my favorite color of zinnia. Clearly the pink plants slowly came to dominate the fields of whoever is producing these seeds, and instead of roguing out some to bring the color mix back into balance, they just let them go rogue, and I got stuck with just one color.
The ‘State Fair’ zinnias were also supposed to be double, like this.
They weren’t. Single flowered forms will almost always come to dominate seed strains unless rogued out because they’re easier for insects to pollinate and thus tend to produce more seed. Clearly no one bothered, because every plant I sowed out gave me just a single row of showy petals.
I’ve had similar experiences with countless other varieties of seed annuals. The picture looks great on the packet, but sow them out and mostly what I get are rogues, not the variety I was after. The lack of roguing is a plague… bad enough that a friend in the horticulture industry once mentioned casually to me that, of course, cosmos varieties are only worth growing when they are first introduced. A few years without good roguing, and their desirable characteristics are mostly lost.
So more roguing please. I love growing big blowsy annual flowers from seed. I’m tired of them all going rogue.
As we get close to the time to start tomato, pepper, and other seedlings indoors, I thought I’d share this picture of my older sister’s seed starting setup from few years ago:
Two desk lamps with compact florescent bulbs. Not traditional, but worked great. Just a reminder that you can get creative when it comes to lighting for seedlings, using whatever fixtures and layout works for your space. The only rules are to use florescent or LED bulbs, not those old fashioned incandescent bulbs which have poor light for plants, and err on the side of more light rather than less to make sure you get compact, healthy plants that will transition to the sunny outside world without drama.
Joseph Tychonievich
I was poking through old photos and came across this oddity:
What you are looking at is Japanese maples (Acer palmatum) being grown hanging upside down. I saw this year ago at a nursery in Japan. (You are also probably looking at a disaster of girdling roots in those tiny plastic pots, but that’s another topic) When I asked about them, I was told that they are weeping forms, and grown this way temporarily before being planted in the ground right-side up.
Looking at the image, it makes me think that the particular variety grown here might have a mutation that makes them negatively gravitropic, and so respond to the pull of gravity in the opposite way a normal plant would. (For more on that see my earlier post on gravitropism in corn) Growing them upside down would allow them to produce a fairly normal branching pattern, and then once plants, new growth would, presumably, cascade down from the established trunk and stem.
Anyway. That’s your oddity for the day.
Joseph Tychonievich
