There are two individual Ficus kerkhovenii figs growing next to the main road just outside the the Maliau Basin Study centre in Sabah. Both individuals can be seen in the photo above.
According to Harrison et al (2003) a study at Lambir (Sarawak) found that Ficus kerkhovenii was the only common hemi-epiphytic fig at Lambir that actually killed it’s host tree by dropping multiple hanging roots to the ground. Once these hanging roots have become established in the ground then the fig rapidly uses its roots to “strangle” the host tree at a collar just below the establishment site of the fig in the canopy (usually the collar is at first branch level) . The host tree soon dies and the fig replaces it.
At Maliau an additional large strangler Ficus forstenii seems to be equally common and uses a similar collar strangling technique. Two additional stranglers Ficus caulocarpa and Ficus virens (both common at Maliau) use a dense network of anastomosing roots to strangle the host tree. Ficus virens with anastomosing roots at Maliau.
These different strangling techniques can be useful for identification.
However the majority of hemi-epiphytic figs at Maliau are not stranglers but kleptocrats or parasites. Once these kleptocrat figs have got a hold on a branch on a host tree they drop down a single root to the ground. The unfortunate host continues to provide support whilst the fig steals water and minerals from the ground next to the host and sunlight in the canopy. Because the fig continues to rely on the host to provide physical support it has no interest in killing the host.
Harrison et al (2003) The diversity of hemi-epiphytic figs at Lambir