Monday, August 18, 2008

Eastern Cactus Conference Mop-up

Ernst van Jaarsveld and the gang judge the Gasteria class (Ernst, literally, wrote the book on the genus).

First off, I have to thank everyone at the Cactus and Succulent Society of Massachusetts for organizing such a superb convention. They really outdid themselves, and I think everyone who attended had a wonderful time. There was one scheduling SNAFU that I noticed, but it seemed to be strictly the hotel's fault, and in any case all the affected events were accommodated the next day, with a pizza lunch thrown in to compensate for the delay.

The quality of plants at the show was outstanding, as was the quality of the plants for sale from the vendors. Somehow, my pot of Burger's Onions (pictured in the header of this blog) managed to take best in division for the succulents other than cacti, which was gratifying. The CSSM club table offered a wide selection of mesembs and haworthias, in perfect shape after being shipped in from the Sphaeroid Institute in California. The banquet was, well, hotel banquet food, but the company was excellent. The auction, which ran until nearly midnight after the banquet, was pretty spirited for a recession year, and it was nice to see some of the more obscure succulents, like Conophytum, inspire bidding wars.

For me, at least, it is the lectures that really make the convention. I missed out on a couple of talks because of conflicts: I regret not seeing Dennis Cathcart's presentation on succulent bromeliads, a subject on which I could use a refresher course, and I hear that Jerry Barad gave a fascinating talk on the early history of the New York Cactus and Succulent Society. I did catch and enjoy Fred Kattermann's talk about Chilean cacti, and two presentations by Panayoti Kelaidis about cold hardy succulents, one dealing with the cultivation of native plants in the arid Southwest, and the other a travelogue of Panayoti's botanical explorations at high altitude in Southern Africa. Mark Dimmitt's slide show about Northern Mexico included some spectacular photography, as well as a lot of solid information about the ecology of the various drought-adapted vegetation types in that part of the world.

Steve Hammer gave two talks. The first, "Snow White and the Seven Hundred Dwarfs," was an overview of the more compact mesembs, including a number of small--in terms of number of species and plant size--genera like Psammophora (which has sticky leaves that catch a protective coating of sand) that usually don't get much love from growers. At his second talk, Steve spoke about hybrid Haworthia, the economics of horticultural fads, and what he thinks of as the futility of keeping track of the pedigree of cultivars. All the while he passed around examples from his haw collection, many of which could no doubt finance a mortgage payment if sacrificed to EBay. As far as I know, all the plants made it back to lectern by the end of the talk, without a leaf missing. Steve's talks are rather similar to his writing: wide ranging but coherent, with a literary quality that is sometimes nearly Twainian, and peppered with allusions to everything from the King James Bible to Brittney Spears.

The most fascinating presentations of the weekend, for me at least, came from Ernst van Jaarsveld, curator of the conservatory at Kirstenbosch Botanical Garden, who was flown in from South Africa by a coalition of American cactus clubs; he was off to Denver after the Eastern Convention. Other speakers may have been more eloquent--Ernst's first language is Afrikaans--or had prettier photos or fancier PowerPoint presentations, but at Ernst's talks, more than the others, I felt that I was learning about things in the natural world that I wasn't aware of before, and in fact hadn't remotely suspected. There is, for example, a succulent grass that grows around Alexander Bay at the border between South Africa and Namibia. Dregeochloa pumila looks like a Peperomia or some such poking out of the sand, but it's in the same family as your lawn. I hardly would have believed it before seeing the images. And no, Dregeochloa is not in cultivation, though Kirstenbosch is trying to acquire material. Also riveting for me was Ernst's accounts of a trip to Dolphin Head in Namibia to see Jensenobotrya lossowiana, Jensen's Grape, at one of its two known localities. I had known the basics of the Jensenobotrya story before, but it was something else entirely to hear a first hand account of its nearly inaccessible habitat on a spire of rock jutting into the icy South Atlantic, surrounded to the east by a sea of shifting dunes, and to see new images of individual plants, seemingly unchanged from their appearance in black and white photographs from 30 years ago. Fortunately for those who couldn't attend the convention, Ernst has written about Jensenobotrya online, at http://www.plantzafrica.com/planthij/jensenloss.htm.

My own talks, one on Conophytum and one on why the names of plants sometimes change in response to new information from modern evolutionary biology, seemed to go over reasonably well. A solid majority of the audience had their eyes propped open whenever I checked, anyway.

Steve Hammer, with a very expensive lump of vegetable matter.

Saturday, August 16, 2008

16th Eastern Cactus Conference - First Day

The Cactus Con is going swimmingly, so far. Yesterday was mostly taken up by settling in and dinner at a fair-to-middling Chinese restaurant called Hong Kong ("Hong & Kong" on the menu), but there were some presentations, too. Chris Allen and Glen Lord gave a demonstration on succulent bonsai, with Chris describing cultivation techniques (from the point of view of a Conophytum grower, he waters and fertilizes the bejeezus out of his caudiciforms, at least in summer, though you can't argue with his results). Meanwhile, Glen, a grower at Bonsai West, talked about how to shear the resulting masses of vegetation.

Then, Fred Kattermann of New Jersey talked about Copiapoa, a genus of globular cacti from the extreme deserts on the coast of Chile. Fred had some really amazing photographs of the little guys clinging to rocks, sinking into clay and leaning out of the sun in habitat. Finally, Matt Mattus of the CSSM gave a charming presentation on a typical yearly cycle of growing Oxalis, Nerine, Clivia and other South African geophytes in his greenhouse.

Here are some photos from the show setup, which I should get back to...

Glen Lord, Steve Hammer, Ernst van Jaarsveld and Abby Rorer discuss plants for the show.

Show setup in progress. Judging theoretically starts in one hour.


Good stuff for sale at the CSSM table, courtesy of the Sphaeroid Institute.


The sale area.


Some of the plants assembled for the auction tonight.

Friday, August 8, 2008

One Week To Go

Next friday, the 16th Eastern Cactus and Succulent Conference starts off a weekend of desert plant-induced nirvana in Chelmsford, Massachusetts, with vendors, social events, auctions, a judged show and presentations by noted succulent plant experts from around the globe. I'll be giving two talks, as well. Every succulent plant enthusiast in the area should try to attend; the speakers list--which includes Steve Hammer from California and Ernst van Jaarsveld from Cape Town, South Africa--is reason enough to be there, and is easily the equal of what you'd get in a national convention.

The preliminary schedule of events is shaping up like this:

Friday - August 15th
  • 4:00 PM Glen Lord / Chris Allen - Succulent Bonsai
  • 5:00 PM Fred Kattermann - The Genus Copiapoa
  • 6:00 PM Matt Mattus - South African Bulbs
  • 7:30 PM Welcome Social
Saturday - August 16th
  • 8:30 Affiliates Meeting
  • 9:00 AM Dennis Cathcart - Succulent Terrestrial & Lithophytic Bromeliads
  • 10:00 AM Jerry Barad - Travelogue or Stapeliads
  • 1:00 AM Ernst van Jaarsveld - Gasterias
  • 12:00 PM Lunch
  • 1:00 PM Fred Kattermann - The Cacti of Chile
  • 2:00 PM Steve Hammer - Mesembs
  • 3:00 PM Matt Opel - Conophytum
  • 4:00 PM Panayoti Kelaidis - Succulents on Skis
  • 5:15 PM Mark Dimmitt - C&S of Northern Mexico
  • 7:00 PM Banquet social/cocktails
  • 7:30 PM Banquet
  • 9:00 PM Specimen Plant Auction
Sunday - August 17th
  • 8:00 AM Breakfast Social
  • 9:00 AM Panayoti Kelaidis - Hardy C&S in Denver OR C&S of the Rockies
  • 10:00 AM Mark Dimmitt - Adeniums
  • 11:00 AM Panel Discussion - the gang
  • 12:00 PM Lunch
  • 1:00 PM Steve Hammer - Haworthias
  • 2:00 PM Matt Opel - Nomenclature & Evolution
  • 3:00 PM Ernst van Jaarsveld - Glories of the Veld
  • 4:00 PM Conclusion ceremony
  • 5:00 PM Conference ends
Monday - August 18th
  • 9:00 AM Optional tour to Boston
My first talk will be on Conophytum, a fairly speciose (almost wrote "specious") genus of compact leaf succulents from the winter-rainfall regions of South Africa. It's quite a diverse group, and includes a number of species of "living stone"--plants that are camouflaged like the local geology--as well as taxa that are specialized for growth on mossy rocks, some that are subterranean, and even a few dwarf shrubs. I'll discuss the plants as they grow in habitat, as well as how to keep them going under glass. Conos are my area of specialization and the subject of my dissertation, but I have to say that with Steve and Ernst in the audience, I'll feel a bit like a punk kid MBA giving a talk on running a successful computer company, with Bill Gates sitting in the front row.

My second talk, on Nomenclature and Evolution, will be experimental; I've never presented anything similar before. I'll talk a bit about how plants receive their scientific names, about species concepts, and about how biologists investigate the evolutionary history of plant groups. But the meat of the presentation will be a series of case studies of situations where modern findings about the evolutionary relationships of succulent plants have forced changes that strike many hobbyists as gratuitously confusing. I will consider shocking consolidations in the mesembs, for example, and investigate the mysterious disappearance of the Asclepiadaceae (milkweed family), former home of the succulent stapeliads. Yeah, it'll probably be a good time for a Dunkin' Donuts run. I'll try to include some pretty plant photos to break up the hypnotic parade of phylogenetic trees, anyway.

Dactylopsis digitata ssp. littlewoodii (center), now sometimes considered part of the genus Phyllobolus or Mesembryanthemum. The plant in flower is Argyroderma cf. testiculare. This is a photo from July 2004, taken in a quartz field near Bitterfontein, in the northern Knersvlakte, Western Cape, South Africa.

Friday, August 1, 2008

Myrothamnus: an African Resurrection Plant

Resurrection plants—or plants that are poikilohydric, in biology-speak—are found growing in seasonally arid sites all over the world. One local Connecticut example is Rock Polypody (Polypodium virginianum), a woodland fern confined to thin to nonexistent soils, often on top of glacial erratic boulders, where it gets very dry very soon after rain. Whereas succulent plants hold onto stored water to survive drought, resurrection plants lose water readily and simply shrivel up when the going gets tough. However, they have the remarkable ability to rehydrate themselves, restart their metabolism and resume growth when moisture is available again. During a drought, a resurrection plant like Rock Polypody will get to the point where it is as crunchy as 10 year old rosemary from your spice rack, yet retain the capacity to spring back to life with the first rain.

A. Dry and seemingly expired Myrothamnus flabellifolius.

The majority of resurrection plants are mosses, ferns and other spore-bearing plants, but there are a couple of flowering plants that are poikilohydric, including Myrothamnus, which is apparently the only woody shrub that has the ability to resurrect. There are two species in the genus: Myrothamnus flabellifolius from arid mountains in Sub-Saharan Africa, and M. moschatus from Madagascar. These two species have a taxonomic family all to themselves: the Myrothamnaceae. A couple of years ago, I obtained a packet of seed of M. flabellifolius from Silverhill Seeds, and now have a good crop of plants to experiment with.

Myrothamnus seeds are tiny, so I planted them in a pot of loose peat moss and perlite mix, right on the surface. The plants come primarily from summer-rainfall areas, so spring is probably the best time of year to get them started. Germination is easy and quick in a seed pot kept in a moist, well-lit location.

Seedlings should be kept moist, in a sunny spot with good air circulation. Initial growth is slow, but as is the case with many plants, growth accelerates as the seedlings gain some size, and in two or three years Myrothamnus can become respectably shrubby. I’ve tried the plants in several types of soils, and they do fine in a range of mixes, with probably the best results achieved in the same airy, acidic mix I used for starting the seeds. Regular applications of dilute, water-soluble fertilizer (e.g., 20-20-20 at half the recommended strength, every 2-3 weeks) seem to be beneficial. The plants do best in full sun.

It’s generally not a great idea to try to test the abilities of resurrection plants in cultivation: they tend to wind up permanently dead if they are dried out too often, or possibly if they are dried out in the wrong way (weather, water quality, soil, and root run are probably quite different in a pot and in the wild, and affect the way dehydration occurs). It’s safest just to keep the plants growing, and as far as I know none actually require the growth –> pseudo-death –> resurrection cycle in order to stay healthy. Still, it’s tempting to play around with desiccating and reviving the little guys, and since I’ve wound up with quite a few Myrothamnus plants, I recently decided to experiment.

Left out in a sunny, dry greenhouse with no watering, my test Myrothamnus was thoroughly dry after about four days. The pleated leaves fold up and turn almost black as they dehydrate, and the plants look pretty sad when the process is complete. I let the plant sit out in the sun for two weeks before taking pity on it and breaking out the watering can. Overnight, the lower leaves expanded and turned green, and in subsequent days a wave of reviving shoots moved up the plant from the base to the apex. A few branch tips had not resurrected several days later, but even these perked up during an afternoon outside in a gentle rain. More extensive studies have shown that Myrothamnus can stay dry for six months with no ill effects, and still recover after nine months, although leaves are lost (Farrant & Kruger 2001). Dry plants give up the ghost for good only after a year baking in the sun. All of this raises an interesting possibility for the desert plant enthusiast with limited winter growing space: you should be able to grow Myrothamnus plants outside all summer, dry them off and toss them into the back of a closet for the winter, and revive them in spring.

B. The same plant as image A., a week after watering.

I've had some minor problems with insect pests on Myrothamnus. Mealybugs and aphids have recently been getting into the plants, so I have experimented with a new type of organic pest control, unfortunately applicable only to poikilohydric crops: let everything stay bone dry for a couple of weeks. It seems to have worked: resurrection plants spring back to life with a little water after an artificial drought; mealybugs not so much. As a bonus, some weeds in the Myrothamnus pots also croaked.

Literature:
Farrant, J.M. & L.A. Kruger 2001. Longevity of dry Myrothamnus flabellifolius in simulated field conditions. Plant Growth Regulation 35: 109-120.