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Ganl. Bull. Singapore 70 (Suppl. 1) 2018 
40-60, 60-80, and 80-100 m. Within each stratum, we generated 20 random points 
as candidate locations for our plots. Our aim was to locate half of our plots of each 
stratum in ‘wet’ areas (defined by the presence of surface water such as swamp pools or 
streams), and half in ‘dry’ areas (without such surface water), taking also into account 
the nine plots from the earlier project phase. We then visited each randomly generated 
location in turn and established a plot if the conditions of the location satisfied our 
targeted plot type. Our ‘wet’ plot conditions were more difficult to sample by random 
chance in the study area, therefore in a few cases where the randomly generated 
location was near to but not directly over surface water, we shifted the plot location. 
The index numbers of the plots that were shifted are suffixed by an ‘a’ (Table 2). 
In each plot, all vascular plant species present were recorded. Where field 
identification was not possible, a voucher specimen was collected to be used for 
further investigation. All woody stems >5 cm diameter at a height of 1.3 m from the 
ground (i.e. diameter at breast height or DBH) were also measured; again, where field 
identification was not possible, an attempt was made to collect leafy twigs as voucher 
specimens. When branches were too high to be collected even with extendable pruners 
(with about 6 m reach), we observed the leaves through a pair of high-powered (10 x 50) 
binoculars, or photographed them with a telescopic lens, and then searched for fallen 
leaves that matched these on the ground. Sometimes, if shorter, younger individuals 
deemed to be of the same species were present nearby and had accessible branches, 
we collected these instead. When the tree crown was too high for the leaves to be 
viewed clearly even through binoculars or a telescopic lens, or where infestation by 
climbers obscured the visibility of the leaves, scrapings of the inner bark and sapwood 
were taken and passed to another project team to extract DNA barcodes (see Kutty et 
al., 2018) as a last resort to provide a putative identification to family or genus. The 
outer bark, inner bark and sapwood characteristics, together with observations of latex, 
resin, or odour, were then used to further narrow down the identity to probable species 
if possible, or were used to complement the identification with leafy twigs or fallen 
leaves. 
The fresh voucher specimens were pressed and dried in an oven at 60°C for 
a few days. To identify the specimens, we consulted published taxonomic keys and 
descriptions, and matched them with other specimens deposited in the Singapore 
Botanic Gardens’ Herbarium (SING) which had been determined by visiting experts. 
Arising from our investigations with fresh and herbarium specimens, we have started 
a series of field guides to various families of trees in the Nee Soon catchment: 
Lauraceae (Chong et al., 2016), Cratoxylum Blume (Hypericaceae; Neo et al., 2016), 
Myristicaceae (Lim et al., 2016), and Xanthophyllum Roxb. (Polygalaceae; Tan et al., 
2016). In this paper, we will focus on reporting the rediscoveries, new records, and 
summary statistics of the flora by family and conservation status. A complete set of 
vouchers, i.e., containing at least one specimen of every species identified from our 
plots, was deposited with the Herbarium, Lee Kong Chian Natural History Museum, 
National University of Singapore (SINU). Collection numbers for the first and second 
phases of the project begin with ‘NSSF1’ and ‘NSSF2’ respectively. If the collections 
were made from within our plots, this was followed by the plot location; if the specimen 
