It is a fine day for a drive wherever you live on our beautiful island. Rain or shine, your drive should include the Panaewa Rainforest Zoo.
This hidden gem in the emerald rain forests near Hilo is home to tigers, macaws and all kinds of wildlife. It also is known for the great collections of palms, bamboos, cycads and tropical rhododendrons.
Today, from 8 a.m.-2 p.m., there is a big plant sale with about 20 vendors. Hawaii Island Palm Society will be giving away rare palm seed, and at noon Tim Brian will lead a palm tour. Even if you live on the Kona side, it is a beautiful drive to view all the spring flowering trees such as ohia, jacaranda, silver oak and African tulip trees along the way.
The zoo sale also will give you an opportunity to meet knowledgeable horticulturists including enthusiastic members of the Palm Society who enjoy sharing their plant-growing experiences.
Of course, they will encourage you to become a member, and that is a good thing. The society supports research, conservation and discovering new species throughout the world. It has biennial meetings for members in exotic places such as last year’s meeting in Borneo. Next year, the meeting will be in the South American nation of Colombia.
On these trips, much of the time is spent studying palms. Perhaps new species will be discovered and brought into cultivation. Soon they might be showing up in local botanical gardens, nurseries and home landscapes. We already have species from tropical Asia, Africa and the Americas, but many more are yet to be introduced.
If you are interested in a once-in-a-lifetime experience, consider exploring the jungles of South America with nature lovers from Hawaii and all around the world. You can get details by checking out the International Palm Society website at www.palms.org.
The Hawaii chapter meets on a regular basis. You can contact Mary Lock at 430-0401 for upcoming meetings, tours and program dates.
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When it comes to palm species around the world, there are thousands with more discovered each year. They come from the high mountains, such as the Andean wax palms that live at 13,000 feet above sea level, to equatorial rain forest species such as those from the Amazon. Desert palms are another large group, but none is quite so close to our Hawaiian hearts as the coconut palm.
The coconut palm group is composed of scores of varieties including some dwarf types that should be used more in Hawaii. Not only are they shorter and easy to harvest, they are resistant to a devastating disease referred to as lethal yellowing.
Palms here have few serious diseases at present. Hawaii’s palms can be affected by bud rot or stem bleeding disease that often is caused by physical damage such as unsanitary pruning equipment or climbing spikes. Most palms showing yellow or stunted growth have been found to be suffering from lack of fertilizer or water.
For example, a recent report came from concerned citizens calling about the dead and dying trees throughout Kona. The trees simply need a balanced fertilizer plus minor elements, applied three to four times per year, and regular irrigation.
All these problems are correctable, but if lethal yellowing ever gets to Hawaii, there’s no practical way of stopping destruction of our island’s palms. Not only would the coconut palm be destroyed, but more than a hundred species of native and exotic palms also would die.
To realize the full potential threat of lethal yellowing, picture the streets of Waikiki and Kahala with tens of thousands of dying coconut palms in all stages of the disease, from the early brassy yellowing of the lower fronds through the collapsing of the crown and the final “telephone poling” when there is nothing more than a naked trunk.
This disease, originally thought to be a disease exclusively of coconut palms, occurs in the West Indies, Florida, Texas, Mexico and Africa. A similar disease occurs in the Philippines.
Lethal yellowing hit Key West, Fla., in the mid-1950s. After a number of years and killing three-fourths of the coconut palms, it stopped. In the early 1970s, it was found in the Greater Miami area. Since the Jamaica tall coconut palm is the species that was planted almost exclusively in Florida, the disease ran rampant. By 1980, most coconut palms in South Florida were dead.
Research at the Coconut Industry Board in Kingston, Jamaica, showed that all varieties of coconuts are susceptible to lethal yellowing. The degree of susceptibility has been the point for developing varieties that are resistant. On the one end of the scale, the Jamaica tall coconut is about 100 percent susceptible. On the other end, the dwarf types are slightly susceptible. Crosses of the dwarf and tall are fairly resistant.
When lethal yellowing hit the mainland of Florida, it was discovered many other palms also were susceptible to the disease in varying degrees. According to the University of Florida Lethal Yellowing Research Station in Fort Lauderdale, hundreds of other palms are susceptible, such as the Manila palm, fishtail palm, loulu palm, date palm, oil palm and many others.
Mycoplasma-like organisms, that occupy a niche between a virus and bacteria, are the cause of lethal yellowing. Mycoplasma-like cells were found in tissues of all diseased palms examined by University of Florida scientists at the research station. They appeared to be transmitted by a leafhopper. Remember, neither the disease nor leafhopper have been found in Hawaii.
Florida embarked on a two-stage program to replant the stripped areas. More than half a million Malayan dwarf seed nuts from Jamaica were imported. The Malayan, while highly resistant to the disease also had the added benefit of easily harvested nuts and did not require expensive nut and leaf removal as with the tall varieties.
Florida researchers also started a hybridization project, crossing Malayan palms with Panama talls that showed resistance to lethal yellowing in Jamaica. The resulting Maypan is highly resistant and also grows with more vigor similar to the Jamaica talls.
Today, a visitor to South Florida would not be aware of the devastation caused by lethal yellowing. Thanks to the efforts of the state and communities of Florida, International Palm Society, Florida Nursery and Growers Association and others, millions of disease-resistant palms were planted.
Hawaii is fortunate to be far from disease-affected regions, but it is vital we don’t introduce this and other plant plagues. It is important to cooperate with the state and federal departments of Agriculture and follow all the rules of inspection.
