Gardening with Georgia

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Saving a Cycad Isn't Easy

Mon, Jul 27, 2009 at 03:37:27 PM


Microcycas calocoma is the handsome dark green cycad in the
 center of this photo. It is complimented with bromeliads.

 

Surrounded by a bevy of big bromeliads, this beautiful Microcycas calocoma is just south of the Visitors Center.  A native of the province Pinar del Rio in western Cuba, this genus has only one species, and is extremely limited in its natural range, according to Loran Whitelock’s The Cycads.  As late as 1998, there were believed to be about 1,000 left, with reproductive female cycads being extremely rare.  But in 2004, that number jumped to about 6,000 in 69 colonies discovered by explorers in the mogotes and rugged hilly habitats in which the cycads are found. The beetles that pollinate them, however, are few and far between, so seedlings seldom are evident.

Fairchild has both the male and female plants.  Horticulture supervisor Christie Jones Leiva says she has just finished collecting seed from the female plants after hand pollination. But for the last few years, there has been a problem with seed fertilization, as well as a fungus that attacks the embryo. Two seedlings from 2,000 seeds have been successfully grown in the last four years. Leiva said she expected 1 to 2 percent of the seeds to be viable this year. Michael Calonje, cycad biologist at Montgomery Botanical Center, has sent off samples of the fungus to the University of Florida in hopes of discovering what it is and how to treat it. That center has 24 seedlings, ranging in age from one to 13 years old, he said.

 The single stem of Microcycas has a corky texture, and the leaves are dark green. When visiting the National Botanical Garden of Havana some years ago, I was told that the cycad is pollinated using a tire pump to whoosh pollen into female cones.The cycad commonly is called the cork palm in that country. Ramiro Chaves and Yuriet Ferrer, Cuban botanists, believe the word corcho, or cork, is used in their country to mean a hollow trunk that is used for a beehive. They have found eight old Microcycas plants occupied by wild bees.

Fairchild’s first specimen of Microcycas came from Robert Montgomery, who founded Fairchild. Montgomery bought two from Charles Deering in 1938. They already were five and eight feet tall and evidently wild-collected, wrote Calonje in The Cycad Newsletter of December 2007. In 1959, Fairchild’s superintendent, Stanley Kiem, went to Cuba to try and collect seeds of Cuban palms and cycads, but couldn’t find Microcycas seed, and brought back some cuttings, three suckers and a small plant as well as a wild-collected seedling given to him as a gift.

It took 15 years for a male plant to develop a cone and 17 years for a female plant to produce a cone. Seeds of those plants are now adults at both Fairchild and Montgomery. It is these cycads that horticulturists now are attempting to fertilize to obtain seed. Back in the late 1970s, Fairchild’s Mary Collins hand-pollinated the cycads twice a day when the female cones were ready. Some 700 seeds were produced and distributed to botanical gardens in the United States and to foreign gardens.

 The showy bromeliads that accent this cycad are Portea petropolitana, with the blue and red inflorescence, and Aechmea blanchetiana, with orange/yellow flower spikes. 

 


 

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