Wednesday, February 29, 2012

Epidendrum , ackermanii Hagsater 2004, formerly known as Epidendrum secundum from Puerto RIco

A plant from Maricao

Side view of the callus of the lip

Front view of the lip

The inflorescence of a plant from Maricao

Cultivated plant, Aguadilla, note that the lip shape and callus are diffent from
 ackermanii, the provenance of this plat is unknown
Plants growing in a landslide, note the purplish color and the small size.
Very small plants blooming 
Epidendrum secundum?  This plant is from Ecuador, growing in great numbers in the roadaside
in the road from Quito to Mindo.

Epidendrum ackermanii is a native orchid of Puerto Rico.  It can be found at middle elevations in many places in the mountainous interior of the island, particularly to the west of the island¹ .  I have found this plant growing in roadsides, landslides, fern prairies and places were the local vegetation has been disturbed or damaged in some way.  I have seen it near Toro Negro and Maricao.  In thirty years of visiting the local forests I have seen it growing epiphytically only once, all the other time it is always growing in the ground, most often under the shade of small, sparsely leafed shrubs that allow a lot of light to reach the orchids.  In Puerto Rico the plant size of this orchid varies wildly, I have found some that were only a few inches tall (which were blooming!) to some that reached two to three feet in length.   The larger and healthier plants are those growing over fast draining rocky ground overlain with a layer of decaying leaves and woody material.   Plants that are exposed to full sun for part of the day but are sheltered from the strongest sunlight at midday by neighboring bushes or trees and have their roots in a spot where there is a substantial accumulation of forest floor litter that is shaded from full sun are usually the largest. 

The size of the flowers and the inflorescence is affected by the vigor of the plant, larger plants produce both larger flowers and more of them.  But in general the inflorescences of ackermanii are quite small and relatively few flowered when compared with plants identified as secundum in horticulture.  I have seen the tiniest flowers and the fewest flowered inflorescences in plants growing in recent landslides, in places where there is little or no leaf litter and the roots are exposed.  Sometimes the plants in these situations are so small it is amazing to see them blooming.

 The leaves also vary in their color, plants growing among the rocks of a recent landslide were only a few inches tall and had a deep reddish purple color, plants growing in a shady location were a deep green.  Flower color is lilac but the shade and saturation of the color varies, some plants have flowers that are a pale rose, other plants have flowers in deeper shades of lilac.

Epi. ackermanii, although it is superficially similar to the cultivated plants identified as secundum that are commonly grown all over the island,  has some differences that easily set it apart.   Wild plants are never seen to form the large tangles of many blooming stems that make secundum so attractive.  Compared with cultivated forms of secundum the inflorescences are few flowered.  The flowers are always smaller than secundum and tend to be closely clustered.  I have never seen Epi. ackermanii in cultivation anywhere, even among fanciers of native orchids, perhaps it is because of the availability of secundum plants with larger flowers in horticulture.   I once took a keiki from a mature plant to see if it would grow in captivity but the plant failed to thrive and eventually died. The Epi. secundum that I have always grown without complaint, it may be that this orchid doesn’t do well under the heat and dryness of the coastal lowlands.

One curious thing about this orchid is that when you visit its native haunts, even thought you can see what seems like plenty of suitable habitat, the plant distribution is patchy, with groups of plants here and there.  The largest group I have ever seen only had a few dozen plants widely distributed over an area of a recent landslide.

¹ Ackerman, James D.  1995.  An orchid flora of Puerto Rico and the Virgin Islands.