Dog Hair as a Rooting Medium

Background:

Dog (Canis familiaris) hair is cheap, abundant, renewable, and produced in such vast quantities that one feels mortally certain that it must be good for something besides canine thermoregulation. Furthermore, most existing rooting media are dependent on the destruction of natural ecosystems (peat moss), require a large amount of energy for production (perlite), or pose a health hazard to the producers and users (vermiculite),¹ so finding a more renewable medium would be a boon to both plant-loving dog owners and the environment.

As canine hair has some qualities in common (holds water, fibrous texture) with other substances used in rooting media and soilless potting mixes, it was evaluated for its potential as a rooting medium.


Experiment:

The floor of a home containing a dog ("Sheba," Fig. 1) was swept, and the sweepings collected into a pile. (Fig. 2) The sweepings were then separated into hair and non-hair, with the latter discarded. (Fig. 3) The material which resulted was fibrous and mostly dark gray in color, with inclusions of lighter matter.²

Fig. 1 ("Sheba")

Fig. 2 (material collected by sweeping)

Fig. 3 (collected material post-purification)
The hair was then added to a plastic pot, 7 cm in diameter. Non-hair material was left out of the pot when it was feasible to separate it. Once the hair had been placed in the pot, it was rinsed with water several times to remove water-soluble contaminants. (Fig. 4)

Fig. 4 (rinsed hair in pot)
Next, the cutting to be rooted was prepared. We selected Plectranthus verticillatus (Fig. 5) as a test subject, because P. verticillatus is known to root readily under a large range of conditions. A cutting approximately 7 cm in length was taken from a plant (Fig. 6), and the lowest pair of leaves was removed.

Fig. 5 (the stock Plectranthus verticillatus plant from which cutting was obtained)

Fig. 6 (Plectranthus verticillatus cutting before removal of lowest pair of leaves)
After making a hole in the dog hair at the center of the pot, the end of the cutting was placed into the hole, and the hair packed around the stem to ensure contact between the rooting medium and the cutting. The pot was then placed in a brightly-lit but sunless location. Moisture level was monitored, and water added when it would have been added for a cutting rooted in soil.


Results:

During the first full watering, a considerable amount of dark brown material washed out of the rooting medium. Chemical characterization was not performed, and the identity of the substance is unknown. Similar but lighter yellow material was washed out of the medium following some but not all subsequent waterings.(Fig. 7) Rooting medium had no discernible odor.

Fig. 7 (drainage water containing uncharacterized yellow contaminant)
The experimental pot retained water much longer than a comparably-sized pot of standard potting mix. However, the distribution of the water was quite different. The upper half remained relatively dry, even immediately following the addition of water, while the lower half stayed very wet. This made it difficult to determine when to water the cutting.

The oldest pair of leaves wilted significantly after three or four days. No new leaf growth was observed; a few small (< 2 mm) roots had formed by four weeks (Fig. 8). This is significantly less root growth than would have been expected from potting soil or water after an equivalent length of time.

Fig. 8 (roots formed after four weeks in rooting medium)
After five weeks, the cutting remained alive but wilted, and had produced no new growth. (Fig. 9)

Fig. 9 (cutting after five weeks in rooting medium)

Conclusions:

Though root development suggests that canine hair may be capable of rooting plant cuttings under some circumstances, development was slow compared to standard media, probably due to the different water-absorbing abilities of canine hair, and it is likely not an acceptable substitute for potting soil.

This experiment also demonstrates that Plectranthus verticillatus, contrary to popular perception, is not in fact capable of rooting in any material, merely in most of them.

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¹ Large-scale production of canine hair also results in the indirect destruction of natural ecosystems and consumes considerable energy, in addition to generating significant amounts of ecologically problematic waste. Objective observation of human behavior to date with respect to animal companions leads us to conclude that humans simply do not give a shit about the ecological impact of their pets, and would continue to attempt to keep domesticated dogs, cats, hamsters, etc. even if forced to live in a poisoned, radioactive, waterless hellscape as a result, because they are adorable and precious, whoosa good dog, whoosa good dog yes you are. If humans are to keep animals as pets in any case, we may as well figure out how to do so in as minimally disruptive a manner as possible.
² The inclusions were primarily composed of household dust, lint, fragments of potting medium from indoor plants, and the fallen leaves of said plants.

[Exceptionally] Pretty pictures: transmitted light -- Part L

Still have a lot of these photos stockpiled from . . . I don't even know how many years ago. Long time. I should probably try harder to burn through those, 'cause I'm still taking new pictures, and at this rate I'll never actually end up posting them.

(The previous transmitted light posts can be found here.)

Tetrastigma voinieriana. Alas, my Tetrastigma was lost in the big scale purge in February. It didn't have scale: I just got tired of it. It was top-heavy, and I couldn't actually let it climb anything like it wanted to, because I wouldn't have been able to take it to the tub to water it, and it had never grown very well, so out it went. I can't say I miss it much, though it's not particularly a bad plant, just not well-suited to my growing situation here.

Platanus occidentalis, autumn. I think sycamores are my favorite outdoor trees. Though tulip tree (Liriodendron tulipifera) is competitive. This particular photo does a terrible job of showing why it's my favorite tree, but that's not really what I was trying to do in the first place so whatever.

Strelitzia nicolai.

Fothergilla x 'Mount Airy.' This was obviously taken at the ex-job; we don't have a Fothergilla here.

Ligularia stenocephala 'The Rocket.' Same here, though I have run into Ligularias occasionally in houseplant books, and have always wondered how well they'd really grow indoors.

The only time I've ever seen anyone come close to trying is when we kept one in the greenhouse at work for a while; it produced some flower buds, which was exciting, but then the actual flowers turned out to have thrips, so they were all twisted and stunted and gross. The whole affair was pretty disappointing.

Plectranthus amboinicus, variegated. I'd like P. amboinicus better as a houseplant if it didn't try to get so big so fast.

Dieffenbachia 'Starbright.' One of the four or five Dieffenbachias I still own. Most of them get thrown out once they get too tall and leggy for me to deal with: either I decide I don't like them and just throw them directly out, or I'm emotionally conflicted about throwing them out, so I try to cut them back and root the cutting, but they don't resprout and the cutting doesn't root and so then I throw them out.

I've always loved the way Dieffenbachias look, and obviously they make for great transmitted light pictures, and it doesn't hurt that they're kind of dangerous -- I like the dangerous plants -- but overall? I don't find them worth growing. The exceptions are the really huge cultivars like 'Tropic Snow' and 'Tropic Rain,' which do well enough for me, and resprout consistently when cut back, that I don't mind having them around.

Pilea 'Moon Valley.' I don't know how many times I had to attempt a photo of 'Moon Valley' before I got this one, but it was a lot. So this is probably my favorite from this batch, whether or not it deserves to be.

Aglaonema 'Sparkling Sarah.' My original plant, which had three individual plants in it and looked decently full, is not as attractive as it used to be, though that's my fault, not the plant's -- I accidentally broke one of the canes off. It's still one of the better red/pink Aglaonemas in my experience.

Caladium 'Fire Chief.' Not a houseplant (though don't think I haven't tried, more than once), but the photos are almost always great.

Five More Plants I'm Not Currently Mad At (H through Pn)

As explained in the first of these posts, I'm currently trying to convince myself that despite a pretty catastrophic spring and summer, some of the plants are still doing reasonably well.

Also I'm trying to justify all the new pictures I've taken recently, since sorting through them all and getting them presentable has taken a lot of my time in the last three or four weeks.


1. Haworthia limifolia var. limifolia

Haworthia spp. and I are not always pleased with one another. Watering is often an issue: their need varies depending on the time of year, and although I know this, I have a hard time remembering when it's time to switch from more water to less water. Most of my plants get the same watering year-round, so there's a tendency to try watering the Haworthias that way too. Then I overwater, and they die, and I remember oh yeah, it's [whatever season it is].

Date: September 2012.
Pot size: 3" / 8 cm (along diagonal).
H. limifolia var. limifolia hasn't had as much of a problem with this as some of the others (it's especially been a problem for H. cymbiformis and Haworthia limifolia var. ubomboensis), though, and in fact has managed to make the most dramatic progress of any of them. Here's what it looked like five years ago:

Date: October 2007.
Pot size: 3" / 8 cm (along diagonal).
Part of the reason it does so much better than the average Haworthia in my care is that it gets better light (from shop lights in the basement) than most of them do. Most of the others have been in my office or in the plant room, and I suspect¹ I've misjudged how much light some of those locations actually receive.

Aside from the light and water issues, H. limifolia var. limifolia has been trouble-free: no insects (that I've seen; it was exposed to the ongoing scale infestation, though I've yet to see any scale on the plant), no complaints about temperature or humidity. I feed by splashing with a little bit of fertilizer at the end of a thorough watering. I haven't had a chance to propagate, though I would like to -- they produce plantlets on runners beneath the soil, which can be removed and potted up individually. Unfortunately, mine has yet to produce any plantlets.


2. Leuchtenbergia principis

I actually have two specimens of Leuchtenbergia principis. The first I bought because it was a cool plant, and I had been assured by PATSP readers that I would like it. The second one I bought because it was an 8-inch (20 cm) pot for $5 (the original was a 6-inch / 15 cm for $25), and I couldn't pass up that deal, duplicate plant or no.²

They're not, as you'll see, particularly rapid growers.

The original plant.
Date: September 2012.
Pot size: 6" / 15 cm.
I probably ought to at least look at the roots sometime soon, if not do a soil replacement or move it up to a bigger pot, but I've been holding off because I'm nervous about it. And fall is a bad time to be doing that anyway.

(original)
Date: somewhere between August and November 2009.
Pot size: 6" / 15 cm.
The other plant is in similar shape:

The later-arriving plant.
Date: September 2012.
Pot size: 8" / 20 cm.
In both cases, the plants have splayed outward a bit in the middle, to try to collect more light. They're in a south window, but there are a lot of things (houses, garages, other plants, walls) blocking the light before it reaches the Leuchtenbergias. Perhaps next year they'll get to spend the summer outside.

The later-arriving plant.
Date: December 2010.
Pot size: 8" / 20 cm.
Other than the splaying, they haven't complained about anything. I wind up watering the 6-inch one about every two weeks, though I slow that down some during the winter. The 8-inch plant gets watered about every four weeks, though it's closer to every two weeks in the summer. Fertilization is as described for the Haworthia. Neither Leuchtenbergia has ever given me any other problems.


3. Pachypodium lamerei

Pachypodium lamerei got to spend the summer outside this year, and responded by growing much more and much faster than I thought it was capable of. The down side to this is that it got top-heavy, and as a result, it got knocked over a lot. On occasion, other plants got knocked onto it, too, hence the lopsided appearance of the plant here:

Date: September 2012.
Pot size: 8" / 20 cm? I'm not sure, and I'm too lazy to get up and measure the pot.
And here it is five years and two repottings ago:

Date: October 2007.
Pot size: 4" / 10 cm.
I've definitely had some problems with P. lamerei in the past: mild cases of spider mites, occasional droplets of a dark brown liquid of unknown origin or significance,³ a tendency to defoliate partially in the winter,⁴ the way they're impossible to handle because of all the stabby spines, etc. But on the other hand, it's still alive and growing after five years, it's looking pretty good, and none of the problems have ever gotten out of control or anything.

Indoors, I water it every two weeks, year-round (unless the soil feels wet -- I do still always check the soil first), with light fertilizer splashed on after the watering, as described for the Haworthia. I try to keep the temperature at or above 60F / 16C. I'd love to propagate this, but it's probably just as well that I can't.⁵ Light is my main problem: last year, it sat in a west window with a bit of supplementary artificial light, and seemed to be okay with that. This year, however, it's gotten too tall to fit in that spot, so I have to give it a less-satisfactory location. It might be a good year to try inducing dormancy, but I probably won't: see footnote 4.


4. Philodendron pinnatifidum 'Spicy Dog'

First up, I have to say: Philodendron pinnatifidum 'Spicy Dog' isn't quite what I'd hoped it would be when I bought it. Nothing wrong with how it's turned out, but it's a lot closer to P. bipinnatifidum now than it was when purchased, and we already had a P. bipinnatifidum. The leaves are a lot more deeply lobed, and the stem's lengthened inconveniently. (I have to prop it up against a wall now, which is only going to become more difficult as the plant grows.)

Date: September 2012.
Pot size: 10" / 25 cm.
It's not really visible in the above picture, but if you were looking at the plant from the side, you'd see that the stem has a fairly pronounced "S" shape to it.

Inconvenient though it is, I'm not mad at it right now because it's always grown well and been problem-free. I mean, if it's too big and has a different appearance than what I wanted, it's hard to argue that those things are the fault of the plant.

Date: April 2010.
Pot size: 6" / 15 cm.
The younger leaves were cooler, though.

It's been getting watered about once a month lately (it might be overpotted a bit). For light, it has four separate windows (east, south, south, west), but they're all at least 6 feet (1.8 m) away, and three of the four are heavily obstructed by plants. How it manages to get by on that is something of a mystery to me, but maybe it's highly motivated: perhaps it knows that it's too big to go anywhere else in the house.

It appears not to mind the temperature and humidity here; I can't recall any pests. Propagation is out of the question, for the same reasons as Pachypodium, but there'd be no space for more of them even if I could propagate.


5. Plectranthus verticillatus

Perhaps an odd choice, but I've been appreciating P. verticillatus a lot lately even though it's one of the few plants that's actually decreased in size since I've had it.

Date: September 2012.
Pot size: 4.5" / 11.5 cm.
The original plant made it up to an 8-inch hanging basket --

Date: July 2010.
Pot size: 8" / 20 cm?
-- and then I took cuttings to make a second 8-inch hanging basket. Plus a whole bunch of 4-inch pots I'd propagated from cuttings. The 4-inch pots all grew a little too well, to the point where I couldn't untangle them from one another, and they were always dry, and I realized nobody was going to buy them, so I threw them all out. And then the two hanging baskets both just kind of fell to pieces. I suspect that was a temperature problem, because I'd put them in one of the worst spots imaginable for a tropical plant: near the floor of the room with the least insulation in the house, and directly in the path of a heat vent. So when the heat was on, they got blasted with hot, dry air, and when it wasn't, they were in a cold draft.

Stupid of me, I realize, but it seemed like something they'd be able to handle (they're ordinarily very tough plants), and I didn't have anywhere better to put them. I took cuttings from those before they had completely died, and those salvaged cuttings have turned into two plants, one of which is pictured above.

As to what it's doing on this list, well, they've been living in the basement for a few months now, and the other day I picked them up to water them and I was like, hey, that's actually really pretty, all dark-green and shiny like that. And they're almost too easy to grow, if you're at all trying: mine get water and fertilizer every two weeks, normal household temperatures and humidity (except when they don't), I've never had a pest on any of them, and they're easy to propagate. They're so fast-growing, it can be difficult to keep them under control, so they require some maintenance, but the fast growth is one of the things I liked about the species originally, so I can't really complain about that too much.


Honorable mentions to:

Haworthia NOID (possibly related to H. truncata)
Hoya bella
Hoya lacunosa
Hoya obovata
Huernia schneideriana
Huernia zebrina
Isolatocereus dumortieri
Myrtillocactus geometrizans
Neofinetia falcata Amami Furan
Pandanus veitchii
Peperomia clusiifolia
Peperomia pereskiifolia
Phalaenopsis NOID
Philodendron gloriosum
Philodendron hederaceum 'Aureum'
Pilosocereus pachycladus

As before, this is not an exhaustive list, whatever it might look like: these are just the plants that I happened to take photos of in September and that are still doing well for me.

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¹ (really more like know)
² I've recently been tempted again, because the ex-job got in two or three three-inch (8 cm) pots, and they're so cute that I just about can't stand it --

-- but so far I've been able to resist.
³ Which has happened both indoors and outdoors, and at different times of the year. It also seems to happen mostly near the growing tip, though I've seen it as low as halfway up the stem. It's relatively infrequent: I think I've only seen it four times? There haven't been any signs of bugs, and the last time, this summer, it happened after a particularly bad falling-over, which makes me think it might be related to physical injury, but on other occasions nothing had happened to it before the appearance of the spots, so I'm stumped. I'll try to get a photo the next time it happens.
⁴ The defoliation isn't necessarily a bad thing: they can go dormant if you withhold water, and then come back to life again in the spring. I don't do that because there's no compelling reason for me to do so. That, and I have trust issues about letting plants go dormant, because I always worry that they won't come back again.
⁵ Supposedly they can be propagated from stem cuttings (though I have no idea how in the hell you'd cut one of these stems) or seeds, and there are on-line sources for seeds, but I doubt I could provide enough light to keep seedlings from etiolating, and I don't especially want to cut my plant down, so we'll let it keep doing what it's doing.

Errata, Taxonomy

I know the Errata posts are not the most fascinating, but I feel sort of obliged -- if I'm going to be responsible for spreading bad information, the least I can do is post the good information when I find what it is. Also I figure some of y'all are nerdy enough to care about these things for their own sakes.

So. In the most recent round of name changes, we have:

Maranta leuconeura kerchoviana.
Maranta leuconeura kerchovEana --> M. l. kerchovIana. It's probably a bad assumption, but I've been assuming that the "correct" version of names is probably the one that shows up most often in Google searches, at least when we're talking about spelling variants. "Kerchoveana" is also pretty widespread, and I'm not positive it's wrong, but it seemed worth changing anyway, since I was already there to update all the posts to link M. l. kerchoviana to the M. l. erythroneura profile, having realized that the odds are very, very slim that I'll ever write a separate profile for M. l. kerchoviana.

Bryophyllum tubiflorum.
Kalanchoe tubiflora has become Bryophyllum tubiflorum.

Aloe 'Doran Black.'
The eternal alternation between Aloe 'Doran Black' and Aloe 'DorIan Black' is once again in a 'Doran' phase, and this had better be the last time I have to change this, goddamn it.

Anthurium crystallinum 'Mehani.'
I've decided I'm pretty sure that Anthurium 'Mehani' is actually A. crystallinum 'Mehani,' as certain other websites claim.

Plectranthus verticillatus.
Plectranthus nummularius got switched to P. verticillatus. I've been calling it nummularius for so long that I don't expect I'll be able to remember this, but we'll see. I pretty much never shut up about this plant, so if nothing else I got a lot of practice typing "verticillatus:" who knows, maybe it'll help me remember.

Phlebodium aureum 'Mandianum.'
Polypodium aureum 'Mandianum' and 'Blue Hare' have been changed to Phlebodium aureum 'Mandianum' / 'Blue Hare.' This is also going to be a tough one for me to remember.

Albuca bracteata.
Ornithogalum bracteatum and O. longibracteatum are now obsolete names for Albuca bracteata. This is also going to be impossible for me to remember, as Ornithogalum has been the name for as long as I've been reading plant books, and has a bit better memory hook ("ornitho" means "bird;" I don't know what the "-galum" part means) than Albuca (no clue, on the meaning of "albuca"). But I will do my best.

Vriesea imperialis.
Alcantarea imperialis becomes Vriesea imperialis, which was long overdue; most people were well ahead of me on that one already.

Justicia scheidweileri.
I'd mentally switched names already, and was using the correct name in the new posts, but I finally went back and changed Porphyrocoma pohliana to Justicia scheidweileri in the old posts.

Astrophytum ornatum.
Finally, in one spot I referred to Astrophytum ornatUM as A. ornatA: ornatum is correct, and this has been changed.

I'm aware of certain other incorrect plant names being used here at PATSP, but I can only stand to change names for just so long before it becomes unbearably tedious. Also: I just don't think some of the changes can be correct (Dracaena marginata --> D. reflexa); in other cases it would be incredibly difficult to go back and make the changes to every post in which the plant appears (Dracaena deremensis --> D. fragrans); and sometimes I just find the new name aesthetically displeasing and am hoping that they'll change it back even though I don't think they will (Synadenium grantii --> Euphorbia umbellata).

Now go and get on with your Saturday.

[Exceptionally] Pretty pictures: transmitted light -- Part XL

Ugh. The Schefflera profile is not going well. I suspect the problem is that I'm trying too hard to work in all the information I found, much of which doesn't actually interest me. Sometimes I have to start the profiles several times before I get any kind of flow going; this may be one of those times. *sigh* (UPDATE: Done!)

As for this post, we have more dead leaves than usual. Some months ago, I went through all the transmitted light photos and rearranged them, rather than wind up with four oak pictures in the same set, so this batch includes some autumn leaves from last fall.

(The previous transmitted light posts can be found here.)

Plectranthus verticillatus.

Platanus occidentalis (sycamore), autumn. This one is much better full size.

Aglaonema 'Diamond Bay.'

Kalanchoe marmorata.

Magnolia sp., autumn. Not sure what it is, but something about this one really appeals to me. Something about the way the veins are curvy. Might be my favorite from the set, though.

Helleborus 'Painted Strain.' Striking, but almost a little too much.

Eucharis x grandiflora, dead leaf.

Quercus sp., autumn.

Dieffenbachia 'Camouflage.'

Alocasia amazonica 'Polly.' I don't think any of the pictures of 'Polly' turned out very well, but it's still striking.