Probably no other plant makes you feel like you're in the tropics like palm trees. But not all palms are from the tropics and not all are from wet forests. Many are found in arid environments all around the world. Palms are diverse in appearance with tall, thin trunks, short, stout trunks, or no trunks - 'fronds' which can be feathered (like the coconut palm), plate shaped or just deeply lobed.
Palms were one of the earliest types of flowering plants (angiosperms). They have occupied parts of Australia for at least 55 million years, if not longer. However, many of the modern Australian palms are more recent migrants from Southeast Asia which arrived here during one the periods when sea levels were low and Cape York Peninsula was linked to New Guinea. Some spectacular native species are easily encountered in Wet Tropics and they are well worth looking for. The Wet Tropics conserves the greatest diversity of palms in Australia - all five subfamilies of palms occur here. Mission Beach (eight palm genera) and Cape Tribulation (seven genera) are particularly diverse areas.
One of the most distinctive palms in the Wet Tropics, the fan palm (Licuala ramsayi) is perhaps best known because of its extensive use on tourism brochures and as a garden specimen in resorts. It appears shrub sized when used in landscaping but these are merely young plants. The fan palm has a central trunk and eventually grows to a majestic height of over 6m with its crown of palmate leaves, each up to 2m wide. It prefers shady, protected stream banks and areas of poor drainage. The Valley of the Palms in the Daintree area is a small area dominated by fan palms which becomes muddy and slightly flooded during the rainy season. Many tall, flowering specimens can be seen at Cape Tribulation and, because these palm grow so slowly, they would be of considerable age.
The mangrove palm (Nypa fruticans) is a widespread species in Southeast Asia and the islands but it is the only representative of its genus in Australia. A most unusual palm, it grows only in soft mud covered by fresh or brackish water in sheltered areas such as estuaries. Each tall, arching frond can be up to 9m long. The fronds extend from thick woody petioles (the normally short attaching stem between a leaf and a branch) that grow from an underground rhizome (or tuber). The mangrove palm produces seeds but it also spreads from the rhizome (a type of root).
The flowers and seeds are special as well. A spike between one and two metres long is sent up from the rhizome and the flowers occur in a spherical cluster at the end of the spike. The fleshy seeds are then produced and these are packed together in a globular, textured cone which arches the spike with its weight. When the seeds are ripe, they drop into the water and float using a cushion of air inside the seed. They are carried to a new spot along the bank where they will eventually germinate and create a new plant. Germination of these seeds takes up to one year!
The mangrove palm is extraordinarily slow growing as well, and sensitive to disturbance so it is unlikely to ever become an addition to the new backyard pond you were planning to put in. However, if you visit the Flecker Botanic Gardens in Cairns, you can see this palm on the banks of Freshwater Lake where it is a much-photographed display item.
With a trunk hardly bigger than a walking stick, the Atherton palm is also aptly referred to as a walking stick palm. It is a primitive looking plant which is the only representative of its genus and is endemic to the Atherton Tableland west of Cairns. The Atherton palm (Laccospadix australasica) occupies an area above 800m where the climate is cooler. It is an understorey species of the rainforest, only reaching a maximum height of two to three metres. Although the walking stick palm usually has a single trunk with fronds extending out from the upper portion, it can have multiple trunks. This unusual habit for a plant is not confined to localities as both single and multiple trunked specimens can exist in the same place. The flowers grow on a long spike that drapes down and outward from the plant. They are replaced by brilliant red, berry shaped seeds tightly packed along the length of the spike.
A series of climbing palms are well known in the area due to their reputation as something to watch out for when walking through the forest. They have many common names but perhaps the most widely used is wait-a-while. This is because, if you get caught in one, everyone else in your group has to wait a while for you to free yourself! The scientific name for one of these climbing palms is Calamus australis and it is very common in the Wet Tropics area, especially in forests which have been disturbed in the past. Calamus is part of the rattan group of palms and is used commercially for basket-making and furnishings. The inner stems of calamus also contain water suitable for drinking. It is the outside covering of the central stems (lianes) which can be painful to stumble into as sharp bristles cover the newer growth. Typical palm feather fronds are clustered at the end of the vine and from this small crown emerges long, whip-like strands covered in small hooks. These help the palm catch onto other plants so that the calamus can grow further up into the canopy. Unfortunately, these stringy menaces also catch onto many an unwary bushwalker who is busy looking at everything else.