THE ADAPTABLE KOWHAI

Forest and Bird, Issue 153, 1 August 1964, Page 11

THE ADAPTABLE KOWHAI

By

J. D. S. ROBERTS

The dainty foliage and blaze of yellow flowers of this indigenous tree are well known to every New Zealander; for in all parts of the country it flourishes. In the rain forests of Westland and around the eastern shores of both islands it thrives. And even in Central Otago, where the average annual rainfall is from 12 to 15 inches, you will find them. There, though not plentiful, they usually attain normal proportions, growing for preference amongst the rocky crags which abound in that district. This seems strange when there are many deep pockets of rich soil where there are practically none found. No reason for this has been given as far as I can ascertain, but it is possible that the heat generated by the rocks is necessary for seed germination.

The tree in the illustration on the inside of the front cover is typical of how they will take root and grow on a rocky bluff. In this instance there is no depth of soil within 50 feet ; yet the kowhai has managed to find precarious hold, and is quite healthy. I have watched it for perhaps 10 years, and its growth during that period has been infinitesimal, as it has no further space in which to expand. Situated some 1,000 feet above the Cromwell Gorge, it may well be over 100 years old; for kowhais, even in the most favourable conditions, are notoriously slow growers. It is hard to understand how this tree, when a tender seedling, was able to obtain enough moisture (and soil) for its development to its present size of about 9 feet. In this case there are no other kowhais within miles. In the same area I have seen a slender specimen of indeterminate age with a cap

of healthy green protruding from the top of a two-inch-wide crack down the length of a large eight-foot-high rock. The original seed must have lodged at the base of this crack, germinated there, and the constricted trunk reached upwards towards the sunlight. As it was unable to increase in size because the narrowness of its imprisoning walls, one cannot but marvel at its hardihood and tenacity of life. And there must be other instances in this dry belt where hardy kowhais have survived under seemingly uncongenial and difficult conditions.