I have come across a number of parasitic plants in Singapore and decided to run an overview here. Parasitic plants, as the name implies, are plants that rely on other plants to support their survival. Usually, the support is partial as these plants are able to make their own food due the presence of green leaves. Some such as the well know Rafflesia, in this part of the world does not have possessed any leaf and hence rely totally on the host plant for survival.
If you are interested to know more about parasitic plants, the Parasitic Plant Connection may be a good resource. In November 2011, a book titled "The Singapore Mistletoe Story" written by Francis Lim was published. This interesting book provides an insight on the common parasitic plants found on trees in Singapore. According to the book, we should have 16 native species although most of them are considered extinct.
The first on my list is Malayan Mistletoe (Dendrophthoe pentandra), a common parasitic plant that attaches to the branches of many trees. This
mistletoe can be found on a variety of host plants. So far, I have seen it on Kopsia flavida (Penang Sloe),
Syzygium aqueum (Water Apple) and Acacia auriculiformis (Common Acacia).
Next on my list is Scurrula ferruginea. It also attaches itself to the branches of trees. Its leaves are narrower than that of Dendrophthoe pentandra and not as
common. It has a rusty appearance. I have yet to see its fruit. So far, I have only seen it in a single location where it attached to the branches of
Syzygium pycnanthum (Wild Rose Apple) and
Melastoma malabathricum (Straits Rhododendron).
The third one on my list is Common Chinese Mistletoe (Macrosolen cochinchinensis). Its overall appearance is similar to the other two plants above
except that it tends to be bushier. I have seen this plant on quite a number of occasions --- on Ficus microcarpa (Malayan Banyan),
Lagerstroemia indica (Rose of India) and Kopsia fruticosa (Pink Kopsia).
Striga asiatica is a different class of parasitic plant when compare to the three described above. It is a root parasite and hence, attaches itself to the roots of its host plants --- usually from the grass family. The Striga asiatica that I have seen so far had yellow flowers although there are those with red flowers.
When I first saw this plant, I thought it was another type of weed since it looks like one and grows among them. The photo on the left shows them (see red arrows) growing among the Cow Grass (Axonopus compressus) and Sensitive Plant (Mimosa pudica).
The one I saw has a height of 10-15 cm. The one with greenish stem and leaves was seen at a different location. This plant is rather illusive and not easy to locate.
Centranthera tranquebarica is probably the most surprising parasitic plant to me. I have first seen this plant in April 2008 at a wasteland area. It took me till January 2010 to find its identity. It is likely a root parasite since it grows among the grasses and weeds. Unlike Striga asiatica where I have seen it at 3 different locations, I saw Centranthera tranquebarica only once.
The next group of parasitic plants are vines and they are leafless. These plants are stem parasites. The first of these plants on my list is Cassytha filiformis.
The next vine-like stem parasite is Cuscuta australis.
Last updated: 28 January 2012