Sunday, February 13, 2011

White Bird of Paradise

What’s happening: Russian olive, juniper and pyracantha berries persist.

What’s still green: Evergreens, yuccas, grape hyacinth, Jupiter’s beard, broom senecio leaves; some grasses.

What’s grey, blue-grey or grey-green: Piñon, four-winged salt bush and winterfat leaves; piñon have been dropping leaves, leaving bare grey stems that make the trees look frosted from a distance.

What’s red/turning red: Cholla leaves, Madonna lily, small-leaved soapwort, beardstongue, creeping mahonia leaves; rose stems.

What’s yellow/turning yellow: Globe and weeping willow branches.

What’s blooming inside: Plants have not moved back to their porch yet, but zonal geraniums are still blooming.

Animal sightings: Flock of large birds flying south Friday morning; small birds out here around noon.

Weather: Morning temperatures are no longer below zero, but are still cold; last snow 2/4/11; 10:11 hours of daylight today.

Weekly update: As winter progresses, the dry air between the storms draws water from plants, dead and alive. At first, the color in pigments intensifies, then, as the season passes, the dead matter blanches.

Cary Pirone was fascinated by seeds of white bird of paradise palms because their feathery caps or arils retain their orange color for decades. Then she discovered why: instead of a plant pigment, they contain one previously found only in animals. Bilirubin develops when red cells break down to produce the yellow found in bruises and jaundice. At that point in its chemical life, it’s insoluble in water, which explains why it persists where water-based plant pigments fade.

Most of us never see those bright seeds. We buy Strelitzia nicolai as a house plant which sometimes produces clusters of white flowers held in dark, boat-shaped bracts. The three white, deeply segmented sepals that give the plant its common name rise above the blue petals that surround the nectary. Two are fused to form a channel for the glucose and fructose, while the shorter, third stands above.

In their native dunes along the South African coast from the eastern cape into Mozambique the Natal wild banana is fertilized by sunbirds who land on the bracts, then walk over the lower petals to get to the nectar. As they move, their feet accidentally pick up and drop pollen. Barbets and starlings eat the fruit and spread the seeds.

Less usefully, vervet and samango monkeys eat the flowers, as do blue duikers and bush babies. Insects visit, but don’t pollinate, while bats and frogs live under their protection and predatory mosquitoes and some fungi live in the joints between the leaves and the woody stems.

If we buy the plants for color, it’s more likely for the green of the great oar-shaped leaves which provide a screen against the desolation of winter.

Writers at the PlantCare website believe the plant’s popularity can be traced to a cover of Architectural Digest from the late 1970's. When the photographers needed to fill some empty space, they brought in white birds of paradise for drama. From there the tropical plants spread, first to decorators, then through the mass market to shopping mall atriums.

The owners of the featured apartment never had to worry about the growth habits of the white bird of paradise. The pots were trucked back to the nursery after the shoot.

However, those who imitated the cover soon discovered the plants can quickly outgrow a normal home. In Africa, where they can receive 40 to 50" of rain a year, the tree Xhosa speakers call Ikhamanga and Zulu call Igceba can grow 40' high. Single clumps can reach 13' wide. When nurseries sell them in this country, they often put two in a pot to give the illusion of fullness.

When I took my current job, the boss’s wife had sent hers to the office where its leaves got in everyone’s way. The foreman pushed it far into a corner, then tethered it to the wall. Whenever the leaf margins split, the office manager hacked it with a knife. It got little water because the flimsy plastic saucer underneath had cracked. They succeeded in killing one of the clumps, but the other survived with a few leaves.

A few months ago we moved into a new office. I had someone buy a larger, stronger saucer and the boss dictated it would be given the window. It spread 60". The tallest leaf reached 76", while the largest leaf blade was 38" long.

When I came in the following Monday, there was a second pot with two more plants. One of my boss’s friends was closing his decorators’ showroom, and the thing had to go somewhere. Its arching stems spread 80", wider than the 6' window, and brushed desks on both sides.

We call these great leaves, so unlike our native vegetation, bananas or palms. In fact, as might be expected of a bird pollinated, animal pigmented plant, they’re members of a small family, Strelitziaceae, with only one species, Phenkospermum guyannense, found outside Africa. They emerged 49 to 55 million years ago when jungles dominated the Earth and color never faded.

Notes: A blue duiker is a small antelope; a bushbaby is a small nocturnal primate.

Frost, S. K. and P. G. H. Frost. "Sunbird Pollination of Strelitzia nicolai," Oecologia 49:379–384:1981.

Letsela, Moeketsi. "Strelitzia nicolai Regel & Koern.," Plantzafrica website, 2002, with additions by Yvonne Reynolds.

Muspratt, J. "The Bionomics of an African Megarhinus (Dipt., Culicidae) and Its Possible Use in Biological Control," Bulletin of Entomological Research 42: 355-370:1951.

Nichols, Geoff. Down to Earth: Gardening with Indigenous Shrubs, 2002.

Pirone, Cary L. Bilirubin: an Animal Pigment in the Zingiberlaes and Diverse Angiopserm Orders, 2010. "White Bird of Paradise - Strelitzia nicolai," available on-line.

Photograph: White birds of paradise, 9 February 2011. The one in front is from the designer showroom; the one in back from a decorator’s house.

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