Native to the Cook Islands (and very similar to Norfolk Is. pines) these are large trees up to 50 m high.
The trunk is straight but, outside its native area including in Queensland it is commonly
tilted or curved and it may branch but this can be also seen in Hoop pines occasionally.
The dark brown bark is rough with horizontal cracks and it peels off in sheets or strips.
The side branches tend to be shorter than those of Norfolk pines.
The upper branches are horizontal but the lower ones droop down markedly.
These features lead to a tall slender column-like tree.
Branches, in whorls are close together making the foliage dense.
The branchlets, in one plane are densely covered in overlapping spirally arranged leaves.
Like Norfolk pines the juvenile and adult leaves are very different.
Juvenile leaves are needle or awl-like, up to 12 or 13 mm long with a pointed tip.
Scale-like adult leaves are triangular to ovate, up to 5 mm long and curved inwards slightly.
Drooping cylindrical male cones, in small clusters can be terminal or in the axils of near terminal branches.
On the lower part of the tree they are up to around 7 cm long and 2 cm wide.
The larger but solitary female cones are usually on a different tree.
On the upper branches the erect elliptical or ovate cones are up to 15 cm long and 12 cm wide.
The scale tip is free and the scales are only partly fused to the bracts.
When mature the female cones break apart releasing the reddish-brown seed scales.
Around 4 cm long each scale has 1 seed.
These trees, seldom seen in Queensland are closely related and similar to A. heterophylla the Norfolk pine.
Young trees which still have juvenile foliage are virtually impossible to tell from Norfolk pines.
Adult Cook pines are narrow and columnar in shape while Norfolk Island pines are triangular.
The terminal branchlets in Cook pines are drooping; in Norfolk pines they are erect.
Both have mature leaves that are flattened and under 1 cm long.
Cook adult leaves are under 4 or 5 mm long;
Norfolk Island adult leaves are 5 to 10 mm.