Visit to Singapore Botanical Gardens

As part of their learning in the topics of Plant Reproduction and Ecosystem diversity, the Pure Biology students were given the opportunity to visit the Singapore Botanical Gardens and National Orchid Garden for a learning journey on 30 Oct 2014. The aim of the trip is to help them to relate their concepts that they learnt to the tremendous diversity of plants as well as understanding the role of conservation of native species and other species of historical tree species, which are called Heritage Trees.

Students visited the new Singapore Botanical Gardens (SBG) Heritage Museum, which shows exhibits related to the historical background of the SBG and how it is intertwined with the scientific, cultural and economic development of Singapore.

The students observed their first heritage tree just outside the SBG Heritage museum, which is the Silk Cotton Tree, or Kapok. The white springy fibers present in its seed pods are used to stuff life jackets, cushions and mattresses. The tree has two interesting characteristics, large buttress roots and thorns on its bark.

The second heritage tree that the students observed was the Tembusu tree (called “$5 tree” as it appears on the back of the $5 Singapore note). There were plenty of red fruit berries produced from the flowering season between the months of April to July. This Heritage Tree is reportedly more than 150 years old.

Students were intrigued by the “Strangling Fig” Heritage Tree, Burmese Banyan. This tree begins its life as seeds deposited in the branches on another tree and subsequently sends its aerial roots down to the forest floor, eventually “strangling” its host tree. To learn more about Fig trees in Singapore, click on the link “Native Fig Species as a Keystone Resource for the Singapore Urban Environment” published by the Raffles Museum of Biodiversity Research, NUS.

After spending an hour observing heritage trees, students spent the next half of the learning journey at the National Orchid Garden. It was a pleasant surprise that we were able to see the “King of Orchids”, Paphiopedilum rothschildianum at the Tan Hoon Siang Mist House in the National Orchid Garden. This orchid is an endangered orchid species endemic to Mount Kinabalu, Sabah, and Malaysia. Its unique features are its green and red spotted petals which are almost horizontal and beautiful pouch-like pink labellum.

There was truly a wide array of orchid hybrids and varieties that can be enjoyed, such as the Phalaenopsis orchids. The two pollinia (pollen sacs) characteristic of all orchid flowers can be prominently seen, as well as the arrowhead-shaped viscidium (sticky pad). The lip (petal) is beautifully modified to serve as a landing platform for pollinators.

Besides relating the reproductive structures of the orchid to their learning in the chapter of Plant Reproduction, the students also picked up interesting points about the growth and habitats of orchids, such as the difference between terrestrial (growing in the ground) and epiphytic orchids (growing on trees). In the picture below, one can observe epiphytic orchid growing on the tree and terrestrial orchids in the ground. This is similar to ferns which can often grow from trees, e.g. bird nest fern, stag horn ferns or grow in the ground.

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Of course, no trip is complete without a group photo. Here’s one taken just outside the National Orchid Garden.