Cryptic cladophylls – stems hiding in plain sight

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.

Terminal stem of Schlumbergera

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.

Euphorb leaves will drop when water is unavailable

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.

Schlumbergera flower

Howdy and Previous Post Revisited 1.0

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:

“So how’s your Puya doing?”

“Fine, thank you!”

Well, mostly.

Long story short, I bought/committed to a Puya berteroniana in 2012.  If you have no idea what I’m talking about:

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…

Still alive, and doing pretty well, but Pootie the Puya really needs re-potting to realize her full potential (the blooms are outrageous, and the point of all this, as I mention here:

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)!

“Mulch Murder” Misinformation

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.

Wrong is wrong

And there it is….Our own Linda Chalker-Scott has been accused of being incompetent and is being investigated by Washington State University. If found incompetent she will be removed from her academic position – in other words she will be fired.

I have had the opportunity to read the investigative report…. And it’s damning.

I mean, you know, if you call 29 pages of rumors, accusations, and the author repeatedly pointing out that Linda isn’t doing a job that she wasn’t hired to do damning.

You can read the report too – it’s over on Facebook.  It’s a closed group so you need to get there through this link

Just ask to join.

So regarding this letter — I call BS (meaning Bad Stuff).

I have two major problems with it. First, the report is packed with unsubstantiated “facts” intended to create bias against Linda, and second, it’s an attack on you.

That’s right. This attack on Linda is a direct attack on you. At this point in time there is no University based extension professional doing a better job of transferring science-based information to the general public.


Linda’s appointment is 100% extension. That means that 100% of her time should be devoted to transferring research based information to you, the public. Well guess how she spends her time? She’s giving you what you, the taxpayer, are paying for. The investigators are saying she should do more experimental work – something she is not paid to do.


Do faculty with 100% research appointments do a lot of work to deliver the work of other researchers to the public like extension professionals? If you’re hired to do a job, you do that job. To do otherwise would be dereliction of duty.

This is absolutely ridiculous.

But let’s be honest, Linda is a polarizing figure (if I had a dime for every time that was said or implied in the text I’d be a rich man). Yep. You’ve got that right. She’s strong willed and stubborn and it comes across in her talks and her writings, and that is part of the reason she’s so compelling. And I say, if she is faithfully doing the job she was hired to do, who cares?

If she were a researcher bringing in a million dollars a year no one would care how obstinate she was.  The truth is that, in her field, Linda is doing better than the researcher who brings in a million. Shoot, there are lots of researchers who bring in a million, tell me how many extension people have won the number of writing awards that she has won, talked to the number of people she has spoken to, or had their work read by as many people as she has had her work read by? As an Extension faculty member who targets the home gardener and arborist Linda is a rock star equivalent to Paul McCartney.

Unfortunately the area that she has chosen to work in, Extension, isn’t seen as sexy and so she is being marginalized.


But that’s just my first problem. And, I dunno, maybe I’m being silly. After all, everyone knows that doing the job we’re hired to do is overrated. Dang, if Linda had had just a tiny bit of foresight and acquired a million dollar grant working on the cell walls of soybean cortex tissue and then published a couple of papers on it we wouldn’t be having this conversation.

Linda, you silly goose!

Don’t laugh, it’s true.

How sad is that?

Not as sad as the amazing quantity of unsubstantiated material that appeared to be present simply to create a bias against Dr. Chalker-Scott in this report. For example, on page 18 we had the opportunity to read about how an Extension Director was displeased with how Dr. Chalker-Scott disagreed with a soil scientist and should respect his opinions. No attempt appears to have been made to contact the soil scientist or to be specific about the disagreement to establish whether Dr. Chalker-Scott might have a reason to disagree.

Apparently simply disagreeing with an expert is a sin in and of itself.

Indeed, throughout this entire report hear-say seems to be the order of the day. Repeatedly we hear that Dr. Chalker-Scott gets the facts wrong, but we never hear the facts she is wrong about (except in the most general way).

This is ludicrous.

But let me end with the most inane thing in the report. Something that is truly staggering. On page 17 it is reported that an employee who was eavesdropping on Dr. Chalker-Scott through the wall “could not help but notice Dr. Chalker-Scott spent a lot of time complaining about WSU to people on the phone.”


That’s in an official report?

I have no words.

Jeff Gillman

Tree of Heck

We have about 3000 sq ft of mixed border surrounding (in multiple layers) our 1500 sq ft home.  We take care of everything ourselves, in our spare time (ha!!).  Thus, our maintenance schedule BARELY includes cutting back perennials and ornamental grasses Feb-March, plus any pruning needed for woodies…then some fits of weeding throughout the growing season.

Most of this stuff has been in the ground for five to eight years, and we have a high tolerance for nature taking its course.  We’re surrounded by deciduous forest, so of course trees pop up where they’re not supposed to, especially oaks and the occasional hickory, which I dearly love and hate to remove. But I do. Because seedling trees are about impossible to just yank out like a weed – a whip just a few feet tall will have a taproot as long.   With our stringent maintenance regime, they’re usually tall enough to poke up over the Panicum or loom over the Leucanthemum by the time I notice, so then digging becomes the only option.

Or, wait, maybe just cut it back really hard, like below the soil line.  That’ll kill it, right? Nope?  Back again? Chop, chop, hack, hack.  Most saplings will give up after a few years. Except this one:

Ailanthus altissima a.k.a. “Tree of Heaven.”

Most of you know this is a totally invasive doody-head of a tree.  Google for details if not familiar.  I thankfully have not had much experience with it, until the past few years – there must be a mature one in the area.  It would pop up here and there in our borders and blueberry field, but I didn’t think much of it. Grab the loppers, cut it back.  BIG mistake.

Behold, the most ridiculous root:shoot ratio ever:

ailanthusrootBunny, our pensive 40 lb whippet, for scale. 

I had lopped this individual back three years in a row. All I could see were the pale, unbranched shoots, not very imposing at all, so chop, chop.   But finally, after a heroic effort last evening, it was successfully ripped from the heart of our main perennial border. Joel had to use our John Deere 950 tractor with a brush grabber chain to get this out of the ground, even after 20 minutes of his digging around the root to get the chain attached.

Like some kind of sea monster, my repeated attempts to kill it apparently just made it angry.  And stronger.

It’s still out there, on our burn pile.
A dog barks in the night.







Founding GP under fire… for doing her job.

Susan Harris over at Garden Rant has done a terrific write up of all the details, so I’ll be brief here: Linda Chalker-Scott, the founder and fearless leader of The Garden Professors, is facing possible termination from her job at Washington State because she’s doing exactly what it says in her job description — extension, providing gardening information to the public — instead of bringing in big research grants. Universities love grants because they means money, and educating the public doesn’t. And money, more often than not, trumps little details like actual job descriptions and the educational missions of public land-grant universities.

Again, for the all the details, please see the Garden Rant post, including info on how to help stop this from happening.


Is a tomato a fruit? Or a vegetable? Yes. And yes.

I’m not sure why this is the question that just won’t die, but I got it again at a event where I was speaking recently, so I am hereby going to issue the final, official, definitive ruling on the age-old question: Is a tomato is a fruit or a vegetable?

The answer is:…

(Drum roll please)


Fruit. And Vegetable. At the same time.
Fruit. And Vegetable. At the same time.

That’s right, folks. Vegetable and fruit are not mutually exclusive categories! Fruit is a technical, botanical term like leaf and petiole and petal which refers to a specific part of a plant. Vegetable is a cultural term referring to parts of plants that we eat.

In other words: lettuce is a leaf and a vegetable, celery is a petiole and a vegetable, broccoli is a flower bud and a vegetable, and a tomato is a fruit and a vegetable.

The real mystery to me is why this question always comes up around tomatoes and only tomatoes, when there are lots of other vegetable-fruits in the grocery store. Peppers, zucchini, pumpkins, eggplants, and cucumbers are ALL fruit. And vegetables. But somehow no one seems to wonder about them.

Joseph Tychonievich