Excerpts from Jim Conrad's
Naturalist Newsletter

from the April 28, 2007 Newsletter issued from Sierra Gorda Biosphere Reserve, QUERÉTARO, MÉXICO

Catching the foreign visitors' attention even more than the Aquiches were the abundant tufted clumps of epiphytic, or tree-branch-living, plants about 15 inches across, with grayish-green, grasslike leaves and long-stemmed, mostly red flower-clusters.

"Are they orchids?" people asked several times, apparently finding it hard to believe that such attractive, epiphytic plants wouldn't be orchids. In fact, until recently there were indeed plenty of yellow-flowering orchids -- the yellow-flowered Oncidiums I told you about in the March 24th Newsletter -- but it looks like someone has gone done the road collecting them. I didn't see a single orchid during our whole walk.

Anyway, the plant putting on our show was a bromeliad, probably TILLANDSIA SCHIEDEANA, a fairly common plant at this elevation from Mexico through Central America to Venezuela and Columbia. You can see one we looked at below:


In that picture the red items in the inflorescence are "bracts," or modified leaves, while the flowers are the slender, yellow things extending beyond the bracts. Bromeliad flower structure isn't like that of most garden blossoms.

If you see a tufted plant growing in a tree and its flowers are arranged in dense spikes, the blossoms themselves are small and inconspicuous but the bracts below the flowers are bright and colorful, a good guess is always "bromeliad." One way to avoid confusing epiphytic orchids with bromeliads is to remember that orchid inflorescences usually lack large, colorful bracts below each flower, and usually orchid roots attached to a tree's bark are thickish and white, while bromeliad roots are typically wiry and dark.

The Reserve's Management Program book lists 19 bromeliad species -- members of the Bromeliad Family, the Bromeliaceae -- of which 13 species belong to the genus Tilandsia.

What a treat to be walking down a road and see something as pretty as this Tilandsia simply growing in a tree next to you. But, what a pain that somebody has gone down that same road stealing the orchids from us all!

from the May 12, 2007 Newsletter issued from Sierra Gorda Biosphere Reserve, QUERÉTARO, MÉXICO

The most abundant bromeliads in trees along the reservoir road are fruiting now, as you can see below:


That's the same species I introduced flowering in this year's April 28th Newsletter. I'm supposing it to be TILLANDSIA SCHIEDEANA. Last month's flowering picture is at this page's top.

In the more recent fruiting picture, the item on a slender stem looking a little like a wad of spaghetti on a fork, at the top, left, is a fruit pod that has split open and is releasing masses of slender seeds bearing long, white hairs. The hairs catch breezes and disseminate the seeds much in manner of how dandelion and thistle seeds get blown about on their white "parachutes." In the picture you can barely make out slender, pale-brown seeds enmeshed in white fuzz.

Last month this species was very pretty with its inflorescence's bright, red bracts and yellow corollas, but now the plants are dried-up, dusty, and cobwebby. Instead of one parachuted seed at a time abandoning its pod, most typically a puff of wind jars loose a whole gob, which catches on the plant's own blades or, more commonly, in spider webs, as shown in the picture.

North America's Spanish Moss, also a member of this genus Tillandsia, produces similar hairy seeds and I've often wondered how such airborne seeds manage to land on a tree limb just right so that the seed eventually germinates and issues anchoring roots. After seeing what happens with our seeds, now I'm imagining masses of fuzz-entangled seeds catching on spider webs, rains come and the whole mess sags onto branch bark, creating a kind of microclimate-producing seed-hair/ spider-web compost capable of retaining enough moisture to help a tiny seed germinate. Maybe spider webs aren't necessary for this scenario, but from what I'm seeing they assist the compost-forming process more often than not. Maybe this is a mutualistic relationship where spiders find homes among the bromeliads, and bromeliad seeds are helped in their sprouting by the spiders' webs.

Not all members of the Bromeliad Family, the Bromeliaceae, produce dry capsules that split at maturity like ours in the picture. The family divides into two large groups, one group forming dry capsules but the other creating berries. The most famous bromeliad is the Pineapple, which produces berries. The part we eat is not that berry, though the berries with their aborted ovules are imbedded in what we eat.