The Norfolk Island pine is a remarkably tolerant species. When it 
regenerates in holes created in otherwise dense rainforest, where it has 
to compete with a large number of broad-leafed tree and shrub species, 
it is capable of fighting its way through to ultimately dominate its 
competitors. It is slow growing at first but, once established, it can 
put on some 60 cm of height growth annually. 
Lane-Poole (1926) indicated that the pine was a slow starter whether 
growing under severe competition in a forest formation or growing openly 
in plantation conditions, or as a horticultural specimen. This is borne 
out by observation of a number of areas established with pine in recent 
years but there is no measurement data to substantiate it. Some of the 
lack of early growth in these areas could be attributed to grass compet- 
ition which develops very rapidly when grazing stock are excluded. 
Subsequent growth in terms of increment in basal area per hectare under 
plantation conditions is almost identical to the growth rates of natural 
regeneration as evidenced by growth data from two permanent plots main- 
tained by the Norfolk Island Administration. Plot 5 is located in natural 
regeneration on a prime pine site. It is typically uneven-aged with a 
wide range of sizes of pine. It has received only one silvicultural 
treatment to remove vines and creepers. Plot 6 is located in a 67-year- 
old plantation which has been fenced to exclude grazing stock for its 
entire life. 
Table 1 summarises the relevant growth data for the two plots. It 
can be seen that basal area growth is essentially the same but because 
of much heavier stocking in the natural forest the growth is occurring on 
more stems and mean diameter increment is half of that occurring in the 
plantation. In plot 6 all trees are greater than 38 cm DBHOB, however in 
plot 5 only 4 trees exceed this size. It is also relevant to note that 
over the past 10 years the height growth of both plots has been very 
similar indicating that the natural stand, which suffered from early 
competition, is capable of similar volume growth once control of the site 
is gained. The pine therefore can tolerate competition in the rainforest 
and produce very satisfactory growth under natural conditions. 
The pine survives remarkably well in the harsh coastal environment, 
withstanding very strong salt-laden winds. It retains its erect habit 
while neighbouring trees and shrubs, especially the White Oak, Lagunaria 
patersonia, assume extreme wind-swept forms. 
The pine is capable of growing on a wide range of soil types in- 
cluding the poorest ridges in the residual forest area, the stoney cliff 
edges where volcanic tuff outcrops and on sand with a high calcareous 
content in a dune reclamation area on the southern side of the Island. 
The Dieback 
In the past the pine has been able to survive to a great age however 
there are virtually none of these broken-topped, hollow giants left. 
The widespread clearing of the forest during the convict settlements and 
the cyclones which batter the island have removed these potential land- 
marks, while the timber getting of the past 100 or so years has taken a 
substantial proportion of those larger pines which might have achieved 
considerable age. It would be very difficult to locate more than a 
handful of trees whose age exceeds 150 years.