Thursday, October 4, 2007

Field trip to Botanic Garden

On Tuesday, NUS students of a biology module on life forms and function went for a field trip to Singapore Botanic Gardens to examine some example of plant structures in nature and relate these to functions.

We had to examine plants from three main categories: mesophytes (plants growing with moderate amounts of moisture), xerophytes (with small amount of moisture) and hydrophytes (growing with abundant moisture).

First stop for mesophyte plants, from a short walk from the visitor centre, will be this strangler Johor fig (Ficus kerkhovenii). Their long contractile roots is for anchorage, uptake of water and minerals and also also, to crush their host trees. These roots are very taut!

The other mesophyte will be this super huge and tall Pandan plant (Pandanus species). This plant has very long and narrow leaves that are pleated, so as to increase rigidity from mechanical damages. There are also spines on the leaves so as to reduce herbivory.

If you look closer on the stems of this plant, there are something growing, like bunch of grapes in green.

And a closer look will let one discover caulifory: production of inflorescences on the trunk, probably to increase presentation to pollinators and/or fruit dispersers. Some birds do not fly as high as some canpoies you see.

This is the famous tembusu tree you may find behind a five dollar note. And these trees are precious in Botanic Gardens, they are protected from lightnings. Can you spot the lightning conductors along the trunk of the tree?

Botanic Garden is a popular spot for wedding photos, we saw at least 3 couples! Ngan Kee, our teaching assistant, speculated they are teachers having time out to do the photo shots since it was Children's day. Anyway, isn't they a sweet looking couple? Nice ah.. on the buttress roots.

This is Vanda Miss Joaquim or also Singapore's national flower. It is actually a cultivated variety of a hybrid. They must be vegetatively propagated or clonally propagated. If you allow these flowers to grow from seeds, different color combinations will arise according to Mendelian's Law. Imagine a Singapore national flower in different colour.

Now over to xerophytes we see Optunia species with fleshy water storage leaves.

Agave species of xerophyte are interesting. They are being planting on Taiwan slopes facing China along the borders. Take a guess why. Clue: they have spines or prickles on their leaves so as to reduce herbivory from herbivores. But the reason for planting in Taiwan is not due to herbivores.

This interesting tree is called the Monkey pot tree. This is not a xerophyte though.

And this is the description, saves me from typing :-)

Back to xerophytes, this bottle tree (Brachychiton rupestris) stores water not in the leaves, and obviously in their trunks. A few of these trees were previous planted and I saw them during my previous trip with the church. However, most died.

Now over to the symphony lake to check out the hydrophytes.

Side distraction: cute duck....

More cute ducks... ok time to move on to the plants.

This is the papyrus plant (Cyperus papyrus) with petioles filled with spaces for better floating in the water.

This papyrus plant is interesting as it was mentioned in the Bible and also was used by the Egyptians to make paper. Look at this part that was already torn when we approached.

When we ended our session, another group was still in discussions. What a wonderful and serene environment to learn things, somemore in front of a lake.

Before we left, this banana-looking plant which is not banana caught some of our attention.

Thanks to Prof Hugh Tan for arranging this and all the TAs for working hard to share so much invaluable informations with us.

No comments:

Related Posts Plugin for WordPress, Blogger...