Tag Archives: nerine dorman

More fun with UV lasers: The Aloe Edition

Aloe bloom

Let me state up front that I hate Nerine Dorman, the acclaimed South African horror writer. This isn’t a minor hate. I have plans for a vicious and vile repayment for everything she’s done to me and for me, and she’ll have earned every last bit. This was the woman who, along with her husband, introduced me to the fynbos, the smallest and most fecund floral kingdom on the planet. They’ve forgotten more about fynbos flora, particularly aloes and euphorbias, than I’ll ever learn, but that’s not why I plan to gain revenge.

Aloe nobilis

It all started this spring, when my aloes started blooming. At this time, I only have two species on hand, A. vera and A. nobilis, and last winter’s repeated Icepocalypses did wonders for all of my South African and Australian flora. Instead of burning off or freezing off permanently, the cold snaps not only encouraged sprouting and growth in Roridula seeds I’d given up on, but it caused a bloom explosion in the aloes.

Aloe blooms
(As an aside, I’m regularly asked at shows by cactus and succulent beginners about their plants’ blooming or lack thereof. While many require at least some cooling period to encourage blooming, the biggest factor is ambient light. With most barrel cacti, regular interference from streetlights, porch lights, security lamps, and other artificial illumination throws off their circadian rhythms, even if it’s only for a few days during their normal blooming periods. I’ve also noted this in such common succulents as jade plants (Crassula spp.), and it’s absolutely vital for aloes. Protect your aloes from light pollution in the spring, and watch them go nuts.)

Aloe blooms
Now, things got even more interesting when taking a closer look at the blooms themselves. They closely resemble the blooms of indigenous North American plants that depend upon either hummingbirds or hawkmoths for pollination, and the confirmation that they had a similar attraction came when a ruby-throat hummingbird proceeded to give me grief when mowing the grass by the aloe planters. There’s a very good reason why Huitzilopochtli, the Aztec god of war, was often portrayed as a hummingbird, as these little monsters have no fear of man, beast, or god, and this one took severe umbrage at my interrupting his feed. Most people would look at the wonder of being attacked by a dinosaur in this day and age and move on, but I needed to know what set off the sort of response more likely to be encountered when haranguing a hummingbird’s nest.

Well, that night, I dusted off the UV laser flashlight used to view fluorescence in carnivores, and tried it on the A. nobilis blooms. The petals fluoresce slightly under UV, but the tips? Those glow a brilliant cadmium yellow, like a black light poster. Considering similar enthusiastic responses from hummingbirds from bladderwort blooms with comparable yellow fluorescence, this suggests either that blooms of this sort offer trace elements in their nectar needed by hummingbirds, or some other factor makes hummingbirds associate this sort of UV glow, and remember that hummingbirds can see well into the UV spectrum, with particularly good food. Time for more research, or at least time to pass on the observations to botanists and ornithologists who can examine things further.

Aloe bloom spike junction

With that observation, I then asked Nerine, without any other familiarity with aloe pollinators, about which birds might be attracted to the blooms. That’s when she informed me of sunbirds (Nectariniidae), which are enthusiastic aloe pollinators. Two groups of birds separated by the Atlantic Ocean, attracted by the same floral cues for the same reasons, and a group of plants able to be pollinated by a bird group from the other side of the planet for precisely that reason…so do the birds call the shots, or the flowers?

Aloe blooms
This is why I hate Nerine as much as I do, and why I’m not going to rest until I come out to her house and talk her to death. At the same time as all of this, I lucked into a copy of the absolutely incredible book Fynbos: South Africa’s Unique Floral Kingdom by Richard Cowling, Dave Richardson, and Colin Paterson-Jones, and now I know where my next trip outside of the US is going to be. As if I don’t have enough realms to research: now I’m addicted to studying fynbos flora, and I CAN’T STOP.

New experiments, from South Africa to Texas

I use one particular phrase to describe my life these days: “I love living in the future.” I was already a correspondence junkie back then, but I’d have never guessed twenty years ago how many interesting folks I’d know from all over the world. Canada, Australia, England, New Zealand, Russia, Armenia, China…if someone offered me the chance to go back to 1991 and had the power to do so, I’d just smile and nod until the schlub turned his back, and then I’d beat him to death with a beanbag chair. (Now, if this opportunity were to stand on a hilltop some 150 million years back to watch the asteroid strike that produced the Tycho crater on the moon, I’d take him up on it. I may be crazy, but I’m not stupid.)

One of those interesting friends is Nerine Dorman from South Africa. Although best known throughout the world for her fiction, she and her husband are South African flora enthusiasts, and she forgets more about South African Euphorbia species in her sleep than I’d learn in a month of Sundays. One of these days, if money and time allow for significant travel, I want to stop by and say hello, and follow her and her husband for the next few days as they showed off local flora. I probably wouldn’t say a word the entire time, except to ask questions while taking frantic notes.

Many other friends describe my enthusiasm for sharing information with such words as “enabler” and and “pusher” and “damn you for making me empty my bank account.” In Nerine’s case, I can say the same thing about her. She introduced me to Silverhill Seeds in Cape Town, which in turn introduced me to what may become my nemesis or my salvation. That plant is Roridula gorgonias.

Both species in the Roridula genus are native to South Africa, thriving in remarkably similar conditions to those of Texas. Superficially, they resemble sticky-leaved carnivorous plants such as sundews and rainbow plants, but they don’t secrete mucilage such as these or dewy pines. Instead, the tips of their leaf threads produce resin. Mucilage allows the transfer of nutrients and digestive enzymes, but resin can’t, so naturalists thought for a century that any insects caught by Roridula were only incidental captures. Technically, since it also didn’t produce any digestive enzymes, Roridula doesn’t technically qualify as a carnivore, as it can’t digest and absorb any nutrients from captured prey.

The reality revealed itself relatively recently. Both species of Roridula have channels in their leaves, and both have unique species of assassin bug that live among the foliage. In the wild, the assassin bugs converge on captured prey in the Roridula leaves, having the ability to pass through the threads without sticking to the resin. They drain the prey, and then later defecate on the leaves. Those channels mentioned earlier trap the feces and allow the plant to absorb the nitrogen and phosphorus within, thereby making it a carnivore by proxy. That is, depending upon the expert you consult, and the discussion of Roridula‘s carnivory is quite the active subject within carnivorous plant circles.

Well, it’s time for the Triffid Ranch to jump into the fray. A fresh batch of seeds of R. gorgonias went into the greenhouse for germination, and since Roridula apparently loves the two things Texas summers have in abundance, heat and sun, I’m keeping close tabs on if and when they germinate. In three years or so, well, R. gorgonias should make a spectacular addition to lectures on odd plants, when these seedlings are full-sized. And until I can get to Cape Town and thank Nerine personally, I’ll have to settle for photos if this little experiment works out.