This story was first published on Nov 27, 2015 and updated on Sept 20, 2016

SINGAPORE - A heritage tree over 60 years old crashed through five apartments at Pearl Bank Apartments in Outram on Sept 11, shattering windows and damaging some units.

The towering Purple Millettia tree, which stood at a height of 32m, was listed as a heritage tree.

Since 2001, more than 200 trees have been accorded heritage tree status by a dedicated panel currently led by National Parks Board's (NParks) deputy CEO Leong Chee Chiew.

The Heritage Tree Scheme, which is open to the public, advocates the conservation of mature trees and includes initiatives such as installing lightning conductors to protect them.

In order to qualify for the status, a tree's girth (trunk circumference) must measure more than 5m. It is also judged on its botanical, historical, social and aesthetic values.

Here are interesting facts about nine well-known Heritage Trees - from the iconic Tembusu and Angsana to the historically significant Flame of the Forest.

1. Purple Millettia (Callerya atropurpurea)

Where to find it: Planted mainly along roadsides in Singapore. There are only two Purple Millettia listed as heritage trees in Singapore.

What's special about it: It is a large evergreen tree with a thick umbrella-shaped or round crown.

Vital stats: The tree is native to the South-east Asian region and can grow up to 40m in height. It has hard, brown and leathery pods that measure about 10cm by 6cm in size. Each pod contains one to two seeds.

Did you know: NParks dedicated the second heritage tree, located behind Swan Lake in the Singapore Botanic Gardens, to Singapore Press Holdings in 2014. The 35m tree was planted in 1889 as a sapling, and has been described as having a dense, dome-like crown with dark glossy leaves and reddish-purple flowers.

The other heritage tree, standing at a height of 32m, fell on Pearl Bank Apartments in Chinatown on Sept 11. It was estimated to be more than 60 years old when assessed in 2008.

2. Tembusu (Fagraea frangrans)

Where to find it: Commonly planted in parks and along roads as it thrives even on very poor soils. Ten have been designated Heritage Trees - including two in St John's Island and one in Sentosa - but by far the most famous one can be found at the Singapore Botanic Gardens.

What's special about it: Two flowering seasons in May and October, during which its creamy white flowers open at sunset and give off a strong fragrance. Its fruits are tiny red berries that are extremely bitter and take more than three months to mature.

Vital stats: Native to Singapore, the evergreen tree can reach heights of up to 40m. It can live more than 100 years.

Where to find it: Mainly parks and open spaces instead of roads (due to the frequent shedding of its leaves) and concentrated at Fort Canning Park and Beach Road. A single Heritage Tree is located at Kwong Wai Shiu Hospital in Serangoon Road.

What's special about it: A semi-deciduous tree introduced to Singapore as early as 1840, it sheds its leaves irregularly and got its name for the scarlet flowers that adorn the tree's entire umbrella-shaped crown when in full bloom. After a leaf drop, it can remain entirely bare for several months.

Did you know: The Heritage Tree, planted by founding Prime Minister Lee Kuan Yew on Dec 14, 1963, is the oldest surviving tree planted by the late Mr Lee. A local book publishing firm, famous for its True Singapore Ghost Stories series, is named after the tree.

Where to find it: Planted in some parks, but also in large numbers in Sentosa and the Sungei Buloh Wetland Reserve. The sole Heritage Tree can be found at the Singapore Botanic Gardens, near the Lady On A Hammock sculpture.

What's special about it: A perennial favourite among children who enjoy picking its bright red seeds housed in distinctive curved fruit pods. It is deciduous and its large, spreading crown is suitable for providing shade in large gardens.

Did you know: Known for its uniform weight (4 seeds make up 1g), the scarlet seed was widely used as a measure for silver and gold in the past. The seeds are inedible and are sometimes used to make necklaces. There is a Google map that lists all the Saga trees in Singapore.

5. Angsana (Pterocarpus indicus)

What's special about it: The deciduous tree is recognisable by its drooping, dome-shaped crown and has fairly fragrant yellow flowers that bloom for a single day. They then rain down the next morning, creating bright yellow carpets on the ground.

Did you know: It is the national tree in the Philippines, where it is known as Narra. Many mature Angsana trees were wiped out in Singapore in the 1990s when they fell victim to a fungal disease, known as Angsana Wilt. In response, NParks' horticulturists propagated Angsana trees that were genetically resistant to the disease.

6. Tempinis (Streblus elongatus)

What's so special about it: The tree's ripe fruit are sweet and are consumed by birds, monkeys and squirrels. Timber from this hardwood tree was once prized for its use in making boats and furniture.

Vital stats: The evergreen tree, native to Singapore, grows up to 12m but can reach 30m in a forest. Streblus elongatus, which means crooked and elongated, refers to its long hanging catkins (flower clusters) that can grow up to 20cm long.

Did you know: Tampines, which used to be a forested area populated by the tree, is named after it. In 1995, then-Tampines GRC MP Yatiman Yusof started a project to transplant the tree all over Tampines so as to help residents become more aware of the history behind the name of the area.

7. Kapok (Ceiba pentandra)

What's special about it: The tree's trunk is usually covered in thorns, and its stiff upper branches - arranged in a tiered fashion - can resemble a pagoda. It is best known for its fruit, which are large hanging pods that split when ripe to release a white cotton fibre used to stuff life jackets, mattresses and pillows.

Did you know: Considered to be the national tree of Puerto Rico, a north-east municipality in the country is named after its scientific name, Ceiba. The first Kapok in Singapore was planted in 1933 by Eric Holttum, a former director of the Singapore Botanic Gardens.

8. Rain Tree (Samanea saman)

What's special about it: There is a variant sporting yellow mature trees that has been planted in Singapore since the 1950s. The tree's crown is covered in clusters of pink-white flowers when in bloom, and its leaves fold up in anticipation of rainy weather - thus its name.

Did you know: In Malay, it is known as the Pukul Lima (five o'clock tree) as the leaves would also close just before sunset. The sunset hour in Singapore used to be at around 5pm until the Singapore Standard Time was created in 1982.

9. Binjai (Mangifera caesia)

What's special about it: A columnar trunk holds up the tree's dense and dome-shaped crown. It is a member of the mango family and its brown, potato-like fruit, sourish-sweet in taste, is used in sambal chilli and rojak.

Did you know: Several locations have been inspired by the tree, which includes Binjai Park, Binjai Hill, Binjai Walk, and Binjai Rise in Bukit Timah. Jalan Binjai, a small street off Haig Road, was also similarly influenced.