THE BROMELIAD SOCIETY
A non-profit corporation whose purpose is to promote and
maintain public and scientific interest and research in bromeliads throughout
the world. There are 4 classes of membership: Annual $10.00; Sustaining
$15.00; Fellowship $25.00; and Life $200.00. All memberships start with January
of the current year.
1977-1980: William Kirker, Leslie Walker, Eloise Beach, Fritz Kubisch, W.R. Paylen, Amy Jean Gilmartin, Edgar Smith, Thelma O'Reilly.
1978-1981: Jeanne Woodbury, Ervin Wurthmann, Victoria Padilla, David H. Benzing, Louis Wilson, Joseph F. Carrone, Jr., Timothy A. Calamari, Jr., Roger Vandermeer.
1980-1982: Doris Curry, Morris Dexter, Sue Gardner, Tim Lorman, Valerie Steckler, Harold W. Wiedman, Charles Wiley, Dale Williams.
Adda Abendroth, Brazil; Luis Ariza Julia, Dominican Republic; Olwen Ferris, Australia; Marcel Lecoufle, France; Harold Martin, New Zealand; Dr. W. Rauh, Germany; Raulino Reitz, Brazil; Walter Richter, Germany; L. B. Smith, USA; R. G. Wilson, Costa Rica; Robert W. Read, USA; W.W.G. Moir, Hawaii.
Published six times a year: January, March, May, July, September, November. Free to members.
Individual copies of the Journal $2.00
Copyright 1980 by the
Bromeliad Society. Inc.
Picture on the cover - Guzmania monostachia. Photo by Alex Hirtz.
EDITOR — VICTORIA PADILLA
Office: 647 S. Saltair Ave., Los Angeles, CA 90049.
KATHLEEN BURT-UTLEY & JOHN F. UTLEY
|Vriesea ororiensis being visited by the hummingbird, Panterpe insignis.|
The following is a republication of a chapter which
appeared originally in "Biologia de las Bromeliaceas" (Museo Nacional
de Costa Rica, San Jose. 1977). The original manuscript stemmed from a request
by Sr. Luis Diego Gomez P., Director of the Museo Nacional, that we compose an
article to serve as introduction to and background for a reprinting of the work
of C. Picado on the faunal associates of Costa Rican bromeliads. In preparing
this work for republication in The Journal of the Bromeliad Society we have
been poignantly reminded of our tenure at the Museo Nacional, the friends we
made and the profitable years we spent studying Costa Rican botany in general
and begonias and bromeliads in particular. We gratefully acknowledge the
resources and facilities of the Museo Nacional de Costa Rica as well as the
assistance of our friends and colleagues at that and other Costa Rican
institutions. While we have made a few minor changes and additions, the
original text remains largely untouched. Department of Biological Sciences
Department of Biological Sciences
Costa Rica has the richest bromeliad flora of any country in Central America; this is also true of the flora in general. Of the approximately 170 bromeliad species presently recorded for the country, a significant percentage are endemic. The Tillandsioideae are particularly well-developed in Costa Rica; about 80% of these species are in this subfamily. One half of the tillandsioid species and one third of the bromeliad flora are Vrieseas. Moreover, well over 80% of these Vriesea species are known only from Costa Rica. In Puya dasylirioides (Pitcairnioideae) and Araeococcus pectinatus (Bromelioideae) are found the northernmost extensions of these South American genera.
At first glance, the great diversity and high endemism of the flora in a country of only 50,900 kms seems anomalous. For its size, Costa Rica, however, has a wealth of habitats. The factors largely responsible for this are climatic and geographic; their resulting interactions have created a wide range of ecologically different environments. This great diversity of habitats has enabled the development of a corresponding diversity of plant species. Few countries, with the possible exceptions of Columbia, Ecuador, and Peru, are able to equal Costa Rica in the richness of its flora. With respect to the Bromeliaceae, Costa Rica has a far greater number of species per unit area than Ecuador. Gilmartin (1973) recognized the great diversity of the Ecuadorian bromeliad flora and observed that it surpassed those of adjacent Columbia and Peru in density.
|Tillandsia insignis growing with many other epiphytes in the extremely wet middle elevations of the Atlantic watershed.|
Costa Rica is a narrow strip of land, at points no more than 200 km wide, extending northwest to southeast; and is bordered on the east by the Caribbean and on the west by the Pacific. Almost one third of the area is mountainous or hilly. Extending from the Nicaraguan border in the north to the Panamanian border in the south are a series of mountain chains which divide the country into Atlantic and Pacific Zones. Both the Cordillera de Guanacaste and the Cordillera Central are of volcanic origin. In the latter are a series of well-known volcanoes which border the Central Valley to the north: Poas, Barba, Irazu and Turrialba. The great Cordillera de Talamanca runs from south of the Central Valley and into northern Panama; thus, there are floristic affinities between northern Panama and Costa Rica. The Talamancas reach a maximum altitude of 3820 m at Cerro Chirripo, the highest point in Costa Rica. The Atlantic slopes of the Talamancas and the other mountains are virtually virgin territory and are poorly known botanically. Combined with the absence of trails and roads, the rugged terrain has made botanical exploration of the area difficult to impossible. The southern Pacific slopes are hardly better known. However, with the construction of the Pan American Highway in the 1940's a section of the Talamancas was opened to development and botanical exploration. With the range in altitude from sea level to over 3800 m, a temperature gradient is encountered in traveling from sea level to the highest peaks. Here, climate has interacted with the topography of the country to form the basis of a series of habitats. The interaction is further affected by both the level of annual rainfall and its seasonality and eventually results in the wide range of habitats encountered in Costa Rica.
There is a marked difference in annual precipitation between the Atlantic and Pacific coasts. Along the Atlantic coast the average annual rainfall is at least 3000 mm and in some areas may approach 6000 mm. Furthermore, there is no extended dry season in this region. In contrast, the northern Pacific coast receives between 1400 mm and 3000 mm of rain annually and has an extended dry season. In the southwestern part of the country the level of rainfall approaches that of the Atlantic side. The Atlantic slopes of the mountains receive rain throughout the year and are much wetter than the corresponding Pacific slopes. This factor alone has affected the distribution of bromeliad species in the mountains. Volcan Congo, just north of Volcan Poas in the Cordillera Central and the Atlantic slopes of Cerro Chirripo have an annual precipitation between 6000 mm and 7000 mm. In one restricted area in the northern foothills of the Talamancas, rainfall approaches 8000 mm annually. Some species found in these areas have not been encountered elsewhere in Costa Rica; this is probably a result of their high moisture requirements and their intolerance of desiccation. Thus, it can be seen that the level of rainfall, independent of other climatic factors, varies tremendously from region to region; and by itself, it is an important factor affecting both species distribution and the morphological forms of species within an area.
The level of rainfall and its seasonality, humidity, temperature variations dependent upon altitude and possibly altitude itself are important environmental parameters governing the distribution of plant species in Costa Rica. Some of these factors have been employed by Holdridge (1967) to form the theoretical basis of his concept of life zone ecology. The Bromeliaceae, and in particular Vriesea, appear to follow the life zone classification closely, and may in fact be extremely sensitive indictators of life zones. This may partially result from their independence of the soil as a substrate and conversely, their greater dependence upon climatic factors. The distribution of bromeliad species in Costa Rica as related to the life zone concept would make an interesting study by itself. Costa Rica has been mapped in terms of Holdridge's classification by Tosi (1969) and gives some insight into the environmental complexity encountered in Costa Rica.
John Utley and R. Chacon collecting bromeliads on Volcan Turrialba.
||The flower of Vriesea leptopoda|
Costa Rica may also be viewed in terms of phytogeographic regions; these regions were first outlined for Costa Rica by Carlos Werckle (1909) and give a broad overview of species distribution within the country. While they lack some of the sophistication and complexity (Tosi recognizes 19 life zones in Costa Rica) of the life zone, they are more straight forward and readily understandable. Therefore, for the purposes of this paper, Costa Rica will be treated as a series of phytogeographic regions: Atlantic lowlands, dry Pacific lowlands, wet Pacific lowlands, 800 m to 1500 m, 1500 m to 2400 m, and above 2400 m.
The Atlantic lowlands extend from sea level to almost 800 m, with temperature ranges between 21 ° and 32 °C. Precipitation is at least 3000 mm/year, but unlike other regions of the country, it is distributed throughout the year. Within the Atlantic rain forests are gigantic trees often reaching 50 m with well-developed buttresses, and a large number of smaller trees forming an understory. From the ground it is difficult to discern much about the canopy. The forest floor itself is dark, most of the light having been intercepted by the canopy and understory vegetation. Small palms are common, as are Dieffenbachias and some species of Cyclanthaceae. There is little evidence of an epiphytic flora, unless it is from an occasional fallen branch or individual plant. Branches of many canopy trees are excellent hosts for a wide range of epiphytic plants including bromeliads, orchids, aroids and peperomias. Along the forest edges and in the occasional pasture trees, bromeliads and the other epiphytes form a more conspicuous aspect of the flora. Here the greater amount of available light enables species from the canopy to invade lower branches and tree trunks. One of the most common species and certainly one of the most spectacular is Aechmea mariae-reginae, which is apparently endemic to the Costa Rican lowlands. Almost equally common is Aechmea nudicaulis. Vriesea gladioliflora and V. heliconioides are found throughout the Atlantic lowlands. One of the most attractive Vrieseas that one encounters occasionally is V. kupperiana, a large species often reaching one and a half meters in diameter. Tillandsia bulbosa is widespread in Costa Rica and is found in this region. Other Tillandsias are also present: T. anceps, T. monadelpha, and T. venusta. Androlepis has only been collected in the Atlantic lowlands.
While the wet Pacific region has a comparable rainfall and temperature there appears to be little overlap in the bromeliad flora. Vriesea heliconioides, Tillandsia bulbosa and Aechmea pubescens occur here but few of the other bromeliad species found in the Atlantic lowlands appear to have invaded the wet Pacific region. Aechmea pittieri and Billbergia macrolepis are sparingly distributed throughout the wet Pacific lowlands. Araeococcus pectinatus, one of the more attractive and seldom cultivated species, thrives on the Osa Peninsula and adjacent mainland areas in the region but not elsewhere in Costa Rica. Three large species encountered near the coast are Aechmea dactylina, A. magdalenae, and Vriesea sanguinolenta.
The dry Pacific lowlands are a marked contrast to the Atlantic lowlands. Here, the dry season may last as long as 6 months, which is probably the principal factor limiting vegetation types. The vegetation itself is sparse and considerably less interesting than that of the Atlantic lowlands. Instead of dense, tall evergreen forests, there are often open deciduous forests and thickets with frequently spiny shrubs. During the dry season the countryside is dusty, bare and brown. Tall Cereus are commonly seen at forest edges. Very few bromeliad species seem to find the dry Pacific lowlands a suitable habitat. One of the more commonly encountered species, and one that is often planted for hedges in a large segment of the country, is Bromelia pinguin. The few Tillandsia species that grow in this area are morphologically adapted to the dry, hot climate and do not extend into areas of greater precipitation. These species include Tillandsia schiedeana, T. caput-medusae, T. brachycaulos and T. makoyana. Tillandsia ionantha is common in other countries but has only recently been collected in Costa Rica and is extremely local in its distribution. Large portions of this area appear to be devoid of bromeliads although it is difficult to say what species were present before the incursions of man and agriculture.
Most of Costa Rica's population lives in the region between 800 m and 1500 m; the country's capital, San Jose, as well as the provincial capitals of Alajuela, Heredia, and Cartago lie in this region. It is a prime area for agriculture; at present, most of the nation's coffee and sugarcane are cultivated here, as well as many truck crops. In the Central Valley little remains of what must have been once extensive forests. Within this altitudinal band are at least 2 distinctly different regions; one encompasses the Atlantic slopes receiving 3000-6000 mm precipitation annually while the other includes the Central Valley with a much lower annual precipitation (1400-3000 mm/year). The bromeliad flora of the Central Valley contains a preponderance of species adapted for the dryer climate. Both Tillandsia schiedeana and T. caput-medusae extend into the valley and are common. A striking variety of T. fasciculata is found throughout the valley, while both T. butzii and T. bulbosa are infrequently encountered. There appear to be relatively few areas in Costa Rica suitable for Spanish Moss (T. usneoides), one of which is this region along a few of the streams. Tillandsia oerstediana, one of the giants of Costa Rican bromeliads is abundant in one restricted area; in flower, it may reach 2 m in height. Its in-florescence is a rich yellow. The sight of 6 or 7 of these plants in flower in a tree is spectacular. Unfortunately, as one looks closer, the dried and dead remains of plants that flowered in previous years become apparent. They are majestic but very mortal, monocarpic bromeliads. This appears to be true of other large Tillandsia species in Costa Rica.
The wet Atlantic slopes at this elevation are unlike the Central Valley. The vegetation of the Atlantic slopes is lush; epiphytes of all kinds abound: bromeliads, orchids, aroids, Blakeas, ericads. Heliconias and ferns cover roadbanks. The majority of bromeliad species in this region are tank-forming types which impound water and various amounts of debris. Some of the species from the Atlantic lowlands extend up into this region (e.g. V. kupperiana, T. anceps). Until recently, this area contained a number of poorly collected and poorly known Vriesea species: V. comata, V. capitata and V. attenuata. Both in inflorescence and foliage, these species are not highly colored; inflorescence bracts are predominantly green and inconspicuous. Without exception, they are night-flowering, producing large whitish flowers which are suggestive of either bats or hawks moths as pollinating vectors. One of the most unusual Costa Rican Vrieseas, V. monstrum, is frequent here. In contrast to the Vrieseas, the Guzmanias are all attractive, colorful species when flowering. Guzmania monostachia literally covers fenceposts in some places, while other species, G. dissitifolia, G. donnellsmithii, G. plicatifolia and G. spectabilis, are sparingly distributed throughout the region.
|Vriesea nephrolepis in the central mountains of Costa Rica.|
Possibly the greatest diversity of bromeliad species occurs between 1500 m and 2400 m, where temperatures are lower and rainfall is abundant. This may also be true of epiphytes in general. Trees are moss-laden, and it seems that every available niche is filled with one species or another. During the dry season the roadbanks and countryside come alive with color. Many trees and shrubs are flowering: Billias, Conostegias and Cavendishias. Fiery Columneas and other equally striking gesneriads accentuate the beauty of the country. Reds, pinks, whites and lavenders or their combinations predominate, with occasional oranges mixed in. Many beautiful, but inconspicuous orchids are nestled among the mosses. The region is environmentally complex with many microhabitats and plant associations. This is in large part due to the effects of the prevailing winds from the Atlantic which race through the many pass areas between mountain chains or peaks, carrying moisture-laden clouds with them. These "wind gap" areas are often cloud-covered, even during the dry season. While heavy rains may not fall, there is frequent light mist. Effects of the wind and moisture are highly visible; trees may be wind-pruned, their branches only developing on their leeward sides. Mosses and lichens are especially abundant. Some bromeliad species in this region, V. incurva, V. chontalensis, T. adpressa var. tonduziana, may be considered xeric. They have poorly developed tanks and a dense covering of epidermal scales. At first glance, it may seem anomalous that species would have xeric adaptations in such a moist, cloudy area. But, in exposed locations, the high winds create a physiologically xeric environment. Other species combat the desiccating winds by impounding moisture in well-developed tanks and are frequently found in habitats or microhabitats that are slightly protected from the winds, the leeward sides of trees or hills or sheltered patches of remnant forest.
Both V. attenuata and V comata creep into the lower and wetter parts of this region which overlap physiologically with the Atlantic slopes between 800 m and 1500 m. Both Tillandsia multicaulis and T. excelsa are abundant in many locations. Tillandsia excelsa is a particular favorite in Costa Rica; their brightly colored inflorescences are at their prime in both form and color during the Christmas season when they are gathered by the sackful to be used later to decorate "portales" (Nativity scenes) found in so many homes. Another species, Tillandsia longifolia, has been used by some families as a Christmas tree substitute. With the exception of V. leucophylla and V. hainesiorum and two species mentioned previously, V. incurva and V. chontalensis, the Vrieseas are night-flowering with dull green or papery brown bracts. In some species, the foliage is very attractive with dark brown or maroon wavy transverse bands. One of the larger species in the region, V. ranifera, forms particularly handsome rosettes with broad dark green leaves whose undersurfaces are suffused with a deep maroon color. Vriesea hainesiorum and V. leucophylla are day flowering species with bright red pendent inflorescences. The coloration of their inflorescences is suggestive of hummingbird pollinators; and, indeed, hummingbirds have been observed and photographed visiting V. leucophylla. With increasing elevation, most Tillandsia and Vriesea species drop out; as a result, the higher elevations in the region (2000 m-2400 m) contain only one or two dominant species of bromeliads.
|Guzmania angustifolia a common epiphyte on the wet Atlantic slopes|
Above 2400 m Vriesea species predominate and form a highly conspicuous element of the flora. They are among Costa Rica's most attractive bromeliads with leaves frequently suffused with dark red and darker wavy transverse bands. The red coloration almost certainly results from the presence of anthocyanin pigments in these species; the development of pigmentation is largely dependent upon the exposure of these plants to sunlight or ultraviolet light. These pigments probably function to shield the plants from the damaging effects of the increased ultraviolet wavelengths at high elevations. Plants that have grown in shaded locations lack much of the red pigmentation and when deeply pigmented plants are brought to lower elevations, they quickly lose their red coloration. This has been a great disappointment to many people who desire to grow these plants for their attractive red foliage. It is possible that these species have a greater tolerance to ultraviolet light than other Costa Rican bromeliads and have, therefore, exploited a habitat that remains closed to other bromeliad species. In a sense, these species form island populations since they are restricted to the very summits of the volcanoes in the Cordillera Central and the higher elevations in the Talamancas, where, even during the dry season, a cloud covering is frequently present. Here, a day-flowering form, V. ororiensis, with bright pink or red bracts forms massive populations; and it is not uncommon to see hundreds of these plants in flower at any one time during the dry season. That these plants are hummingbird visited is obvious to even the most casual observer. Another potentially hummingbird visited species, Puya dasylirioides, is one of the two North American representatives of this Andean genus. It is found primarily among the paramo vegetation in the Talamancas in massive populations; however, it does grow at elevations as low as 2400 m, but then only in montane bogs. Unlike Vriesea species which at these elevations are highly colored, Puya develops little pigmentation. However, in appearance these plants are silvery, resulting from a dense covering of trichomes. These scales probably reflect much of the incident light and in this manner protect the plants from the effects of ultraviolet light. (To be continued).
NANCY B. GREENFIELDWho loves bromeliads more than I do? You'll never guess! Butterflies arrived en masse this summer to visit my mini-jungle especially the Spanish Moss (Tillandsia usneoides) where they hovered around enjoying the small fragrant blossoms. This was their first visit to my bromeliads, and I hope it won't be their last.
The butterflies were gorgeous reflecting a chestnut brown body, with cream bands on their wings, and a brilliant cerise red spot near their heads. They hung like bats on the Spanish Moss, and then skipped around to view my other plants. On walking out in the yard I was immediately surrounded by these lovely butterflies. Several of them also inspected Tillandsia stricta and perched there for a time. I found them down in the vases of the aechmeas using them like a delightful pool of spring water.
My bromeliads are growing in many different media — on trees, in the ground, in dirt, and in river gravel. They are all doing well and relish the Florida weather. On two palm trees in my front yard I attached several types of bromeliads, and Aechmea orlandiana has now produced at least 75 offsets on each tree completely surrounding the trunk of the Royal Palm. What a sight this was on Christmas all in bloom! Also in bloom on the palm tree is Aechmea 'Maginali' with its bright red berries for the Holiday Season.
On another palm tree in the front yard there are at least fifty Billbergia porteana that were given to me by a grower who said they had never bloomed for her. I attached the six she gave me and now they have multiplied with at least fourteen blossoms appearing all around the trunk of the tree. This bromeliad is absolutely magnificent and one of my very favorites — exotic beyond belief. Visitors to our area stop their cars to see this beautiful blossom and can hardly believe their eyes.
Growing bromeliads is an extremely fascinating hobby — always more plants to discover, more facts to learn, and more people to meet who share your interest.
In an extended population of Tillandsia secundiflora var. major near Vilcabamba (Dptm. Loja) we picked up a plant, which looked at first like a Tillandsia secundiflora. It has now flowered in the Botanical Garden at Heidelberg; it is not a T. secundiflora, but a beautiful new Tillandsia, which according to the formation of blueviolet-red floral bracts, was called T. rubro-violacea.
Plant stemless, flowering up to 80 cm high; leaves numerous forming a rosette of 80 cm in diameter; sheathes broad-ovate, 20-23 cm long, 12-13 cm wide, violet-brown in the base of the upper side, light-brown beneath; blades lingulate, attenuate, 30-35 cm long, 5-6 cm wide, on both sides adpressed lepidote and waxy near the base; scape erect, thick, round, glabrous, green; the basal scape bracts subfoliate, the upper ones long-ovate, attenuate, with a winered, glabrous sheath and a spreading lepidote, diverging blade; inflorescence bipinnate, cylindric, 10-20 cm long and 3-4 cm wide, with 15 erect spikes; primary bracts shorter than the spikes, carminred, green to the base, enfolding the bases of the spikes; these erect, adpressed to the inflorescence axis, short and stout pedicellated, complanate, 5-9 cm long, 2-3 cm wide, with 5-6 flowers; floral bracts densely imbricate, 2,5 cm long and 1,5 cm wide, intensive blue-violet at their tips, otherwise carminred and green to the base, equal to the sepals; these membranaceous, their acute tips pale-violet, the posterior ones carinate and for 7 mm connate; petals 3-3,4 cm long, narrow-lineal, blue-violet, whitish at the base; stamens and style included.
This decorative plant was collected near Vilcabamba, growing between rocks, under the number RAUH 38 328 a (Sept. 1973)
If this operation is carefully done and the cut tissues treated with Captan, it is possible that the old plant may produce one to five successive offshoots from the uninjured side. These later plants may be generally more easily removed than the first one. It takes some courage as well as a surgeon's skill to attempt this operation, especially if you have only one plant in your possession.
Guzmania sanguinea will produce its new offshoot in the same location as V. splendens. Offshoots of V. fenestralis generally appear halfway between the axis and the basal leaves. These are more easily removed.
Fertilizing — Weakly and Weekly
My investigations into the nutrient requirements of atmospheric tillandsias indicate that a weak solution of soluble fertilizer applied at weekly intervals will provide a good supply of minerals. The fertilizer should be about half the strength recommended for other plants and sprayed to just wet the leaves without any appreciable run off. If you prefer to dip the plants, shake the plants lightly upside down when removing from the liquid. I fertilize all my tillandsias this way including tiny seedlings and recently planted seed.
Atmospheric tillandsias do not appear to show distinct deficiency symptoms when subject to moderate starvation, and this makes evaluation of any nutrient deficiency difficult. Silvery leafed tillandsias receiving insufficient fertilizer just seem to adjust their growth rate/size to the available nutrients. If you have been under fertilizing your plants, the above program will give any one or all of the following improvements:
- Faster growth
- Larger more robust growth
- Larger inflorescences and
- More offsets
Many propriety brands of soluble fertilizers lack magnesium and calcium. This can be corrected by adding a little magnesium sulphate and calcium nitrate when making up the solution.
Bromeliad Society of Queensland, Australia
MULFORD B. FOSTER
(Reprinted from Vol. II, Issue No. 3)
On our first really major expedition for bromeliads in Brazil in 1939 we discovered, quite by accident, that most of the epiphytic, broad-leaved bromeliads could not tolerate certain chemicals, especially copper.
A rather important aspect of collecting is the proper numbering of each plant correlating to the number in the collection book where the location and descriptive data are written in detail. It has always been a difficult problem to attach collection numbers so they would not be lost during transportation and the fumigation processing upon entry into the United States. Cheap but fragile paper or cellophane tags proved to be easily torn off and the written numbers soon faded, so I decided on a metal tag which had, unfortunately, a copper wire for attaching to the plant. I wound this wire around the tough caudex, but also, in many instances where plants had wide leaves, I pierced the leaves with these copper wires and thought the tags were certainly secure. In nearly every instance except in plants with the stiff, xerophytic, terrestrial plants such as Dyckias, Hechtias, Ananas, etc. the leaves soon showed injury and the infection traveled the length of the leaf, often rendering the entire leaf worthless, and what was more, we lost the important numbered tag. I changed my method after losing several records, and now instead of copper wire which the bromeliads could not tolerate, I use an aluminum band to wind around the base of the plant.
The potency of even a small amount of copper was shown when a copper tack accidentally dropped into the leaf cups of a bromeliad; it burned a hole through several layers of leaves; if it is dropped in the heart of the plant it might even kill the entire plant.
My next experience in learning about the detrimental effect of copper on bromeliads was when one of my men sprayed some nursery plants with a copper sulphate solution. I lost hundreds of bromeliads which were near the sprayed plants.
The same fatal result was caused when we sprayed a number of nursery plants with a solution containing arsenate of lead. It was a very windy day and the spray was carried over to the bromeliads; our loss was very serious.
A few years ago I used a much advertised product to kill slugs and sow bugs which were injuring small seedlings. To my surprise our loss of bromeliads of all sizes soon after that was a real calamity. The sow bugs ate the material and then went to the bromeliads for water! The result was a great shock to my struggling bromeliad collection. Upon investigation I learned that the killing agent in this product was arsenic. I was learning the hard way what bromeliads could not tolerate.
Another poison that takes a very heavy toll of bromeliads is the methyl-bromide treatment given to plants at all U.S. Plant Quarantine ports of entry to the United States. While orchids and many other plants are affected, bromeliads take a loss in a more fatal form than any other plant family with which I have had any experience. The broad, shiny leaves of plants such as vrieseas, guzmanias, tillandsias and any of the more delicate species of aechmeas and billbergias are very susceptible to this "death-chamber" gas treatment. It is not uncommon to lose fifty percent or more of the treated plants when importing them, and almost never is there a bromeliad which comes through uninjured. Many of the injured plants are one and two years recuperating from the Quarantine Station treatment.
Even so simple and frequent an occurrence as water dripping from galvanized pipes or wires in the greenhouse will cause serious injury and often death to a bromeliad. It is the zinc from the pipe which bromeliads cannot tolerate. And this intolerance has been used to advantage in destroying bromeliads.
Tillandsia usneoides (Spanish Moss) and T. recurvata (Ball Moss) are two bromeliads that have been considered pests when they grow in such profusion as they do in Florida and other southern locations. There is a great difference of opinion as to whether the Spanish Moss is beautiful when draped from the trees or as to whether it is a detriment and a pest. Most people believe it to be a parasite and are convinced that it kills the trees — that is, of course, erroneous. We do know, however, that it will grow vigorously in a tree that is in poor health as there is less foliage to shade it out. It also grows profusely in the coastal deciduous trees such as Taxodium commonly called "Bald Cypress."
In cities such as Orlando, Florida, where the moss grows in great profusion, much money has been spent to de-moss the thousands of live oak trees that line the streets and grace the lawns of private dwellings. Many residents, too, are either very strongly against or in favor of the "unsightly" or "beautiful" tree drapery that decorates their trees. Good tree climbers and de-mossers are scarce and expensive. This epiphytic bromeliad is tenacious of life; it has an indomitable will to live. One little section of moss left hooked on bark or branch soon grows to be a festoon.
Now, in this instance, instead of trying to find a way to prevent death to a bromeliad a way has been found to kill them. The Davy Tree Expert Co., having spent many years preserving plant life, has now become interested in eradicating the Spanish Moss and through experiments of Mr. L. V. Newton, the local representative of the company at Orlando, they have finally perfected a formula that is quite efficacious in this project.
The trees are now sprayed by a high-powered sprayer, with a solution of 150 gallons of water and four pounds of arsenate of lead. This will give a complete kill if every section of the moss is hit and in four weeks there are no signs of life in the moss, although it may be several months before the dead strands have completely fallen or been blown from the trees. Care must be taken at the time of spraying and it should not be done at the period in the spring when the new young foliage of the trees is appearing, as this strong solution will burn such tender growth.
For this de-mossing process a solution of Sulphate of Copper-Neutral may also be used in a like proportion, but death is slower and it generally takes three months for a complete kill.
In a recent article in our local newspaper the following appeared: "As Spanish Moss is a striking part of the Florida landscape and does little or no damage to trees, Dr. George Weber of the University of Florida College of Agriculture is in favor of leaving it alone."
That the moss does little or no damage to our Florida trees has been my conclusion ever since I came to Florida in 1923. The oldest native tree on the Atlantic Coast, "The Big Cypress Taxodium distichum which lives just a few miles north of Orlando, is estimated to be over 3,500 years of age, it is covered with moss — and if moss kills trees as many people state, then it is taking quite a time to kill this grand old monarch of the forest.
It is very important to know what is best to keep bromeliads alive, but it is equally important to know what is fatal to them. While most of our experiments have been along lines of research as to what is most beneficial for their well being, we have learned that there are at least four mineral elements that are quite toxic to them, copper, zinc, arsenic and lead, so we should make every effort that these elements do not come in contact with our bromeliads.
D. C. SPEIRS
The Calgary Zoo, Alberta, maintains a large conservatory of tropical plants as part of its aviary. Bromeliads are a prominent feature of the ground cover, although surprisingly few are grown epiphytically. Aechmea dominates with such reliables as cv. Foster's Favorite and Vriesea is not far behind; V. splendens is common.
The bromeliad display is fairly young, the older parts having been planted three or four years ago, and blooming is almost continuous through the year, with a spring burst as the weather improves. Bird damage appears minimal as far as I could see.
The photograph gives an idea of some of the plants to be found. Aechmea calyculata has an interesting yellow inflorescence and Vriesea imperialis dominates one display by virtue of its imposing size, reaching waist height.
WILHELM WEBERDuring the frost-free season I put part of my bromeliads outside, since the plants thus get a more intensive leaf color from the full sun, grow more sturdy, and then are better hardened off for the winter in the greenhouse. I made an interesting observation last summer in a Neoregelia coriacea blooming outside on my patio. Whenever a few flowers were open, ants would appear and would crawl into the flower tubes, where they were apparently clambering for the nectar. They were also not hindered in their efforts by the water in the center of the plant. The individual flowers sometimes barely stuck their tips out of the water, but the ants conquered the wet barrier to get to the sweet nectar. You can see the visitors in their endeavors in the accompanying color picture.
It would be very interesting to know whether similar observations have been made in the native habitats of the bromeliads and whether ants are possibly pollinators of certain species of bromeliads.
Bromeliad fans are traveling more and more often to the tropics and are collecting in the natural habitat. We have often read comments about biting ants that commonly inhabit the hollow leaf sheaths of bulbous species. But relatively little has been said about the significance of these ants for the bromeliads and little has been said about the other fauna associated with bromeliads, i.e. what animals live in, around, or from the bromeliads. Travelers should therefore note the animal world while collecting bromeliads and bring back photo documents and reports.
We know, for example, almost nothing about which insects and which larvae live on bromeliads.
Years ago in a shipment from Brazil I received a Tillandsia stricta, on which sat a little gray-green caterpillar eating a leaf from its tip down. I was astounded by the fact that this caterpillar demonstrated such a fine mimicry; it was hardly visible on the plant. The color fitted the Tillandsia stricta exactly; even the scales were imitated so perfectly that I noticed the caterpillar only by accident.
Another case of symbiosis of bromeliads and insects was demonstrated to me by a small branch with a tillandsia from Peru. Here I found an egg-shaped swelling, pointed at both ends, on one of the roots. It was about 5 mm long and 3 mm in diameter. A small, round opening on the side showed me that it was the abandoned gall of a little gall wasp or gall gnat. It is probably not known what species of root galls appear on tillandsias and on other bromeliads.
These examples should be sufficient to show that there are many more things that the attentive traveler should not overlook in the tropics, because they, too, belong to the better understanding of the nature of our favorite pets.
German Democratic Republic
HOWARD H. CONVERSE, JR.It was recently brought to my attention, through a community education Orchid/Bromeliad Culture class which I teach, a very unique method of constructing a miniature greenhouse for the germination and growing of bromeliad seeds. This method is by using the two-liter soft drink bottles currently on the market. A lot of people have been using the black plastic bottoms for flower pots and this miniature greenhouse goes one step further. I will outline step by step the procedures in making such a germination greenhouse.
STEP ONE: Remove the label from the bottle. Some brands on the market have labels sealed by means of a hot-glue process and nothing will remove these labels but good hard scraping. Most bottles have a partial label and are sealed only on the side edges. These are very easily peeled away.
STEP TWO: The top of the bottle must be cut away. Make a cut approximately ½-inch up onto the angled top of the bottle. Trim away any ragged edges.
STEP THREE: Now insert your finger just under the edge of the black plastic bottom where the clear plastic joins the bottom. With a hard pull the bottom will snap free. This will expose the rounded domed top of your new greenhouse.
STEP FOUR: Fill the black plastic bottom with sterile peat to about ¼-inch from the top. Prepare a label for the seeds to be planted. Sprinkle a small portion of seeds over the top of the peat leaving about ½-inch border on all sides. Now insert the open end of the clear plastic borne down into the peat and black plastic bottom. You now have a very useful and attractive miniature domed greenhouse.
Manufactured into the black plastic bottom are several small slots. These make the necessary drainage or watering ports. To water just set the planter into a shallow container of water and let it absorb upward through the bottom of the pot.
Seedlings can be grown under these conditions for several months depending upon the species or genera. After they have reached the desired height they can be transplanted into large community pots or seed flats. This whole process provides a terrarium condition and keeps the required amount of moisture around the seeds until they germinate.
Florida State Museum, University of Florida, Gainesville, Florida 32611
|STEP ONE: REMOVE LABEL||STEP TWO: CUT AWAY TOP|
|STEP THREE: REMOVE BLACK PLASTIC BOTTOM||STEP FOUR: INVERT CLEAR TOP AND PLANT SEEDS IN STERILE PEAT|
This letter has been written many times in my mind this past year, and now that it is written I hope that it does not offend too many people.
Too many hybrid plants are running around with the same looks but different names; or worse yet, plants with little value are being sold with catchy names with poor quality under the guise of registered hybrids. Genetics plays an important part in this problem and has not been properly explained. First off, let me explain that my partner, Bart Schwarz and I have been growing house plants commercially for the past four years, with my personal experience with bromeliads for eight years. Mr. Schwartz has been hybridizing gesneriads for the past twelve years.
The same principles which guide us in choosing a plant for commercial production should be used in the releasing of new bromeliad hybrids, namely that the plant have outstanding qualities, have exceptional traits, and be distinctive from other hybrids. Since it does take so much time to produce bromeliad hybrids, I suggest the adoption of the same rules as used by the Orchid Society. In order for hybridizers to reveal their crosses, they should be protected in some way. Ed Hummel is said to have not revealed his crosses because he was "ripped off" by other commercial growers who remade the cross, shipped the seeds to Europe and flooded the market with the plants. Since then, the only way to buy a true Hummel hybrid is by vegetative offsets. Even so, they are still sought after, and the integrity of the plants to name is better than some of the registered hybrids I have seen lately.
A case in point is Neoregelia × Fancy Free. No two plants in the cross were alike, as I remember Joe Carrone's words. Each plant is also genetically distinct as well, and if used in future breeding will produce different results. This will only serve to compound the confusion which is rampant in hybrids already.
When making a hybrid, one should realize the importance of the proper choice of parents. Most crosses, so far, have been primary; that is, both parents are species. If the species is seed true, that is all progeny from that species are identical, the two species when crossed usually produce identical offspring. These are termed F1 hybrids and the cross is said to have F1 uniformity. My knowledge of genetics is not extensive, and I am sure some will quarrel with some of this.
Now if the species are not stable and produce variable offspring, such as in the case of Aechmea chantinii and Neoregelia concentrica, a wide range of plants will ensue from them.
Secondly, when hybrids are selfed, the range of plants will be even more pronounced and often the worst traits of both parents will show up in these plants. Anyone who has grown the seedlings from hybrid marigolds knows this. The same holds true for Neoregelia × Oh No!, which is self fertile. These plants produced from seed are not N. × Oh No! This is important for both amateur and professional alike to know.
The next confusing and most complex is the hybrid which uses one or both parents which are themselves hybrids. Here it is possible that all offspring could be different. Should all of these bear the same name? The rules state that they should, but I disagree! We have such a hybrid, and many of the plants have merit, but some will be thrown away or sold as unnamed hybrids.
Since most bromeliads are purchased by mail order, it seems important to me and my fellow mail order brothers to protect the integrity of named plants and hybrids. Lately I have heard people state that they will only purchase plants which they have seen first hand! This will be hard on us who survive by mail. The naming and labeling of plants is important in the bromeliad world as it is to all hybridizers, and to this end, I heartily subscribe to Nat DeLeon's responsible hybridizing practices and ask that others join in! Let us also remember that a pretty plant, grown to perfection is still a pretty plant no matter what name it is given, and a "Dog" is still a "Dog", no matter what kind of fancy name is attached to it.
711 Via Hermosa, Danville, CA 94526
The San Fernando Valley Bromeliad Study Group announces that its annual show and sale will be held on May 31 and June 1 at the Valley Plaza Recreation Center in North Hollywood, California. All members are cordially invited to attend. Hours are from 12 to 5 on Saturday and from 10 to 4 on Sunday.
Q. Does water in the cups ever cause the plant to decay? Some of the leaves of my nidulariums seem so brown and mushy around the base. Also what would cause large brown spots to appear on my nidulariums? Do I give them too much light?
A. In the first place, all of the tank type bromeliads must have water in order for them to live. The other types of bromels do not have cups so they could not hold any quantity of water. If your plant is in a greenhouse and there is a drip from above that may bring foreign substances or if you have sprayed with oil or arsenate of lead, decay would easily start in this cup because of the poisonous chemicals. A drip going directly into a plant from an overhead galvanized pipe would soon cause some serious consequences.
Bromels that are living on rocks or in the ground withstand much more adverse conditions as they have built up a resistance to the greater predominance of chemicals which are prevalent in rocks of soil in greater quantity. Also, the roots have a tendency to take up sufficient water necessary for their sustenance. But when the tank bromeliads which depend on their leaves and the base of their leaves to absorb and digest their food, have an over abundance of chemicals such as iron, copper, etc., they do not have the resistance to tolerate more than their minute needs.
It has been authoritatively said that one per cent of our air is mineral and from that one percent such plants as Spanish Moss and the xerophytic epiphytes must receive the greater part of their mineral needs. Sufficient organic material reaches many of these epiphytic plants from decayed leaves, twigs, bird droppings, numerous insects, etc. All provide a balanced chemical ration.
The mushy leaves around the base of a nidularium could not come from decay in the cup unless the whole plant was decayed. As long as you will have to cut your fingernails and your hair you will have to take off the lower leaves from your bromeliads as they mature and decay naturally. But if an abnormal number of leaves are rotting off at the base, foreign substances are entering the cup, or your potting material is not correct.
Most of the species of nidulariums are shade loving plants. All bromeliads want light and plenty of it, but do not confuse this with sunlight; nidulariums do not want much direct sunlight. For the most part they live on or near the ground floor of the forest. They enjoy plenty of moisture and like a humid condition, not dry air. If your potting material is allowed to get soggy and is poorly drained and that generally means that it is turning sweet, then the nidulariums and most of the bromeliads do not like this condition so they try to tell you they don't by rotting. Old leaf-mold or osmunda fiber will break down in two years and ceases to be acid. It becomes sweet but it smells sour. Most plants do not like it. Replant your bromeliads once a year if possible for their best health and growth.
Q. I notice that the offshoots of two plants of Guzmania magnifica are variegated, though the parent plant in each instance has plain green leaves, is this a natural occurrence or is it a mutation?
A. It is doubtless a mutation and could be caused by a virus or an injury. If the variegation continues from generation to generation you have a variety; however, this variegation may appear in one plant caused by injury to the cells and would not repeat itself in the next generation.
I believe that most variegated bromeliads have first appeared as seedlings. If this variegation is carried through to the mature plant you may have a good chance of producing this plant in quantity through offshoots. In some cases the variegated seedling may have but one or more variegated leaves; if so, you still have a chance of procuring a well variegated plant if you carefully watch the new offshoots as they appear after maturity of the plant. If you are fortunate in selecting an offshoot that appears directly under the variegated leaf, you will quite likely have a plant with all of the leaves showing variegation. In this case you may have a continuation from generation to generation of this consistent variegation.
The seeds of variegated plants such as Neoregelia carolinae var. tricolor have consistently produced the original type plants without variegated leaves. The seeds of Bromelia serra var. variegata and Cryptanthus bromelioides var. tricolor have produced albino plants which have lived but a short period. I have never had any of them exceed an inch in height before they died.
There is still much to be learned as to the causes of variegation in bromeliads.
Q. I have trouble in keeping my offshoots in the soil or bark in which I plant them. The least little touch, and out they come. How can I prevent this?
A. Perhaps you cut them off too early. It would be best if you could wait until a root had formed before removing offshoots. If not, then make a hairpin shaped piece of stiff wire, about six inches long which has been covered with plastic, and arch it over the stubby base down into the soil.
W. W. G. MOIRMore and more the growers of bromeliads are led blindly into growing neos and their hybrids. No end of neo plants look alike, some with a little more red color than others. Many crosses are just a matter of crossing something that is red with anything that is redder, the grower little realizing that a great many of the progeny are going to come out green and only a few being near what he wanted. I received the selfed seed of Neo. carolinae, a very dark red form, from a friend on the mainland and grew a lot of them. Only a half dozen were dark and only one had a real red center like the 'tricolor' form. The majority were green without even a red center on flowering, and none of the reds looked as beautiful in the garden as the 'tricolor' nor were they as large growers. None of these reds looked as fine as "Fireball" or the cross of farinosa × carolinae, or half as nice as tristis × marmorata.
The problem with these neos is that you have to be right on top of them to see what they are like; they are first-class prima donnas in the garden and are easily damaged by hot sunny weather. Our large masses of "Fireball" are indeed showy in the garden and outshine many of the other neos but do suffer in the summer.
We get greater enjoyment from the big splashes of color of the large sprays of aechmeas, porteas, vrieseas and the new × Portemea 'Luis Ariza Julia' which last for months as the highlights in the garden display. When you see dozens of strong spikes of Ae. mulfordii and many, very tall and massive × Portemea 'Luis Ariza Julia', plus Ae. eurycorymbus, Portea leptantha and Portea petropolitana var. extensa you think of all the possibilities of crossing them. The first four are in a range of colors from yellow through shades of red. The Portea petropolitana is very different in color having salmon pink stems and lavender flowers and should be crossed with a compatible color combination. The inflorescence lasts for six months on the plant and is the focal point from our bay window, and other vantage points.
Guz. lingulata, in a bed under tree ferns, also stays in bloom for six months. Vr. glutinosa, with its many branching stalks, likes a bit of shade from the tree ferns. Canistrum aurantiacum, a large strong plant, likes the sunshine, and its scarlet cup of bracts with deep yellow flowers is different in form — more like an oversized rose. All of these plants carry their blooms for months and do not have problems in the hot summer time.
I have been discussing the value of the above plants with a young bromeliad enthusiast, who is also landscaping with bromeliads. I have explained the value of these beyond their use in landscaping such as the use of their flower sprays as cut flowers or be allowed to stay on the plants until they are beginning to fade and dry. At this point they can be used as interesting dry material for flower arrangements. The dry sprays often last for years. The best plants for this are Aech. mulfordii and × Portemea. The mulfordii grows to be 3 to 4 feet in height and the Portemea can even be 7 feet tall. If the sprays are taken off at 4 to 5 months, at the peak of their color, they will keep their color for months. If one wishes, one can heighten the color of the dry spike with a waft of spray paint in orange or red color months later to be used again and again.
We rarely cut our Guz. lingulata while they are red in color because we know they are going to last for six months, but when they finally start to fade they change to subtle apricot, then creamy yellow and finally cream tinged with green. These delicate shades of color add a great deal to a flower arrangement and keep well in water.
Just think what could be done with breeding some of these into even more striking hybrids. Just who would have said that the cross of × Portemea 'Luis Ariza Julia' would come out twice the size of its parents in some plants (Aech. mulfordii and Portea leptantha). The possibilities of getting many more large species from the tropics and adding them to the mixture are great, except that it is hard to produce the seeds. We seem to flower these crosses a year or two ahead of the seeds grown by the hybridizer. Our trouble is that we are running out of space to grow these spectacular plants.
Our plants of Vr. glutinosa, a fast growing bromeliad that clumps rapidly, have seeded themselves in the garden as well as hybridized and are welcome highlights. We have not experimented with using the spikes as cut flowers as the seeds are in demand.
Already we have noted quite a difference in the variants of mulfordii; we have both a difference in size of plants and intensity of color of inflorescence, so in propagating them further we should seek the more spectacular ones which are larger. Likewise in the × Portemea we find quite a difference in plants, unfortunately the biggest and best does not set seed but maybe they will breed with others as males.
Just think of the terrific new crop that could be raised by nurserymen, especially in tropical countries. These cut flowers could replace the great importation of temperate zone flowers to tropic areas. Just think how much these large stalks could cheer up a dreary winter when one is shut in the house in the north with a splashy display of color and then be allowed to dry to go on and on and even reused later. Huge arrangements of any height could grace hotels in their lobbies all winter long with little care.
My good wife has used Aech. mulfordii spikes for years in the floral sculptures she does weekly at the Honolulu Academy of Arts. For some years, books on this work have been available from her notes made over the years.
Aech. mexicana, with their fabulous heavy spikes of ivory berries are a feature display in the month of February, months after the other aechmeas have gone. Of course the weight of these would make shipping prohibitive.
There is a wide field of possible breeding that is waiting to be done which can be much more intriguing than the little neo. × neo. × neo. process. I guess the difference between my point of view and others is that I enjoy an ideal tropical garden site while others have greenhouses and winter to contend with. But there are lots of bromel growers who do not live in a hardship area so why not try breeding in a different direction. Think of the landscape material, the cut flower business and a whole new array of color. We are hoping for a blue flowered spray from the cross of Aech. dichlamydea var. trinitensis on Aech. fendleri that might make a fuller and longer spray, than fendleri.
Among the smaller plants, not neos or nids, there are those which do not mind being picked up bodily and used for a couple of weeks in the house in an arrangement. Tillandsias do not need water in cups to survive, neither does Aech. orlandiana. When set back in the garden they go right on making new growths for the following year. Yes, neos can be brought in, but you had better be sure they have water in their cups. They can best be enjoyed in a flat dish arrangement so you can look into their cups. Do not think we do not enjoy the neos; in fact, we have them planted in masses and grouped together so one can compare their similarity and differences. Try giving the big bromels a go and make some new landscape and cut flower material — a lovely possibility.
The Ballona Valley Bromeliad Society invites all members to their annual show and sale to be held at the Veterans Memorial Hall in Culver City, California on Saturday, July 26 from noon to 5:30 and on Sunday, July 27 from 10 to 5:30. This corrects an earlier announcement.
The Los Angeles International Fern Society is holding its 17th annual Fern and Exotic Plant Show from 9 to 5 on July 19 and 20 at the Los Angeles State and County Arboretum in Arcadia, California. All shade loving plants, including many bromeliads, will be featured.
This plant is a natural hybrid, which grew with hundreds of other dyckia seedlings in the pebble beds alongside my small pool. The seeds are either thrown here by the mother plants or are blown here by the wind. Luckily, our wet season occurs at the same time, which seems to suit the germination of the seed.
I have obtained some good dyckias from this bountiful source. Most of the plain green seedlings I have destroyed; otherwise I would be overrun by a dyckia invasion.
The plant shown here is remarkable for its multiple spikes. The adult plant threw four primary stalks. One split into two, and these split again in four as shown on the right of the picture. Two stalks divided into two and the third spike divided into three, making eleven flowering spikes for the original four peduncles. Is this unusual in a dyckia or have other members encountered this phenomenon?
I do not know the parentage of this hybrid and will not be able to register it, but I am thinking of calling it cv. 'Multi-spica'.
All visitors to Florida should include in their itinerary a trip to the Marie Selby Botanical Gardens situated in the lovely gulf town of Sarasota. Not only have the Gardens been designated as the official bromeliad identification center, thanks to the donations made to the Mulford B. Foster Memorial Fund set up for this purpose, but they are fast becoming the world repository for all things pertaining to the Bromeliaceae.
The most recent donations are those received from Racine Foster of Orlando. Besides a number of very important books, journals, and papers, she presented to the center a set of color Xerox copies of many of Mulford Foster's botanical drawings. It is hoped that others who have drawings, books, and films of bromeliads which they deem to be of interest and importance would follow Mrs. Foster's generous move.
It has been learned that a well-known orchid grower sends to Selby one of each of the orchid specimens which he collects on his expeditions (The Gardens are also the center for orchid identification). Those bromeliad growers who travel south to increase their collections would certainly be doing a great service to the plant world if they would share their bounty of new species with Selby. Many plants, bromeliads included, are rapidly becoming extinct in their native habitat due to the razing of forests to make way for new roads, habitations, and agricultural land. The only way these species can be preserved is by collecting them and then growing them on in a botanical garden where they will receive the proper attention. Sarasota is the ideal spot for bromeliads, and those that are grown here flourish as no where else.
Contributions to the identification center are still being accepted.
Mr. Harry E. Luther, long a member of the Bromeliad Society, is in charge of the identification center and will welcome your donations. He writes that he wishes more members would send in plants for identification. (See page 36 of Issue No. 1 for this year for instructions). Presently he is working on a series of articles covering species frequently misidentified in cultivation.
VERNON STOUTEMYERThe induction of flowering in plants is obviously complicated and the mechanisms differ in different groups of plants. Some plant physiologists believe that a still undiscovered hormone, usually termed "florigen" or "anthesin" is involved. Probably there are yet unknown hormones or growth regulators in plants, but all attempts to identify a specific substance causing flowering have failed. Several investigators have been able to extract substances from plants in which flowering has been induced and to apply them to non-induced plants and produce flowering. However, not only have other experimenters been unable to repeat these results consistently, but the original investigators themselves have had inconsistent results. One of these investigators claimed that the effective material in his preparations was an acidic substance of unknown composition. Unquestionably, the five recognized plant hormones can be involved in some way in the flowering of certain plants. We can mention briefly the following facts:
- Auxin can produce flowering in pineapples and some related
plants, but not in other major plant groups.
- Ethylene production as a result of the application is the
usual explanation of the above response. Ethylene can produce flowering in
- Abscisic acid generally acts as an inhibitor of flowering.
Other inhibitors may also be involved in the control of flowering in plants.
- Gibberellin can substitute for the necessary cold treatment
in rosette plants such as cabbage, carrot or spinach. It is probably involved
in the flowering process of a fair number of plants both as a promoter and an
- Cytokinins are known to be involved in flower production of
some plants. Recent studies by Ramina et al. (1979) and by Even-Chen et
al. (1979) showed that cytokinin promotes and gibberellin inhibits
flowering in Bougainvillea. All these investigators considered both hormonal
and nutritional factors to be involved in the flowering of this plant.
After flower bud initiation occurs, a profound redistribution of nutrients often can be observed within plants. The flower bearing areas act as metabolic "sinks" which cause a flow of nutrient materials from other parts of the plants. Vegetative growth is often slowed down greatly because of the flowering process.
The older generation of horticulturists and plant physiologists made many observations on the nutrient status of plants in relation to flowering and fruiting. Treatments which reduce vegetative growth such as girdling, removal of young leaves, or the use of dwarfing rootstocks tend to promote more abundant flowering of woody plants and have been widely used in commercial fruit growing.
Phytochrome, which we have discussed previously, was once claimed to be the flowering hormone, but this was soon disproved. However, it is unquestionably involved in the mechanism by which plants which are sensitive to day length are induced to flower. These plants can distinguish different daylengths, since they have in common with many animals, built-in circadian rhythmic processes (approximately 24 hours). The German plant physiologist, E. Bunning, deserves much credit for establishing an understanding of this wide-spread biological clock mechanism on a firm basis.
The hormones or substances causing flowering are thought to be identical in long day and short day plants, since, if a part of an induced plant can be grafted to a non-induced plant of the opposite category, the flowering stimulus will cross a living graft union.
Some entirely different and unique proteins can be found in the early stages of flowering organs. Some fruitful studies are in progress on the chemical changes in plants which result from the action of the two alternative forms of phytochrome. We can expect steady progress in the difficult field of flowering biology. In spite of some truly notable advances in recent years, it must be admitted that the whole field is still in a somewhat unsatisfactory state.
All of the factors we have mentioned are undoubtedly operative in bromeliads. All growers know that bromeliads have to reach a certain size before they can bloom. Thus, there is a nutritional factor involved. They also tend to have definite bloom periods and thus are sensitive to daylength. Accordingly, phytochrome presumably is a trigger mechanism in these plants also, but we do not know of quantitative studies. Bromeliads are known to respond to auxin and ethylene or ethylene producing compounds. Thus hormone action is undoubtedly also involved in flowering of bromeliads.
Even-Chen, Zeev, Roy M. Sachs and Wesley P. Hackett. Control
of flowering in Bougainvillea "San Diego Red". Plant Physiol.
Ramina, Angelo, Wesley P. Hackett, and Roy M. Sachs.
Flowering in Bougainvillea. Plant Physiol. (1979)64:810-813.
Ramina, Angelo, Wesley P. Hackett, and Roy M. Sachs. Flowering in Bougainvillea. Plant Physiol. (1979)64:810-813.
It is imperative that you get in touch immediately with the new Chairman of the Affiliates in order that his file may be brought up to date in case he should have to get in touch with you.
Please send the names of your officers and your mailing address to —
2546 Folsom Street
San Francisco, California 94110
If you have trouble bringing up seedlings, try adding a little vinegar to the water. Our water supply is too alkaline here in New Orleans, and I find all the bromeliads improve with the change.
Try foliar feeding on your bromeliads if you haven't already done so. We have been spraying the leaves with a dilute solution of liquid fertilizer every three weeks with astonishing success. Several plants bloomed that have never shown a sign of an inflorescence in several years.
I have also been having luck with my vriesea seedlings. It is a lot of patient work, but I have been cutting off the silk from each seed before planting. I suspect that lessened the danger of fungus.
Morris Henry Hobbs (January 1955)
Aechmea mariae-reginae is perhaps one of the most conspicuous bromeliads to be found in Costa Rica. It usually is found growing high on tall trees in dense, hot, humid forests at elevations of 1,000 to 4,600 feet, the tall bright red inflorescence brightening the somber green of the forest in which it lives.
The above photo, taken by Alice Quiros who recently moved from southern California to Costa Rica, was taken from the kitchen window on the family farm in Orosi. Here this aechmea grows happily in a temperate climate in either shade or sunshine among the impatiens which have become a pest in the coffee plantings.
This spectacular plant is much esteemed by the Costa Ricans who use it for church decorations and in religious celebrations.
In cultivation Aechmea mariae-reginae needs the protective warmth of the greenhouse in order that its full beauty may be realized. When purchasing a plant, one should keep in mind that this is a large species, attaining a spread of three feet or more.