Manuka Blight Seen As Danger To Hill Pastures

Gisborne Herald, Volume LXXVII, Issue 23218, 1 April 1950, Page 8

Manuka Blight Seen As Danger To Hill Pastures

“Though evidence is not yet con elusive it appears that the scale insect responsible for the death of manuka is not a native of New Zealand, but probably came from Australia. Therefore, the blight must be considered in the same category as all other introduced plants and animals.

“Experience has shown the danger of the uncontrolled and unrestricted introduction of many plants and animals which later have become weeds and pests, and to take unnecessary chances with manuka blight would be rash

This is an extract of a statement in an agricultural newletter issued by the Department of Agriculture following a meeting of representatives from interested Government departments to consider the implications of the dissemination of insects for manuka destruction. “To the farmer manuka is a weed which invades some pastures and ultimately may take control of them unless it is held in check rigorously,” it savs ' 'To the forester and botanist manuka constitutes an ideal nurse crop for many native trees. To the soil conservator manuka is a type of cover which helps to reduce erosion and runoff on poor, reverting hill-country. “Thus if is evident that manuka in its right place is of the utmost value from the point of view of forestry and soil and water conservation: in the wrong place it can become a serious problem in pasture management. Therefore though the destruction of manuka is eminently desirable on many thousands of acres of grassland, it is relevant to consider what would happen if the many millions of acres of land sub-marginal or economic for farming were stripped of the protective covering which this plant affords. "The problems of manuka invasion differ intrinsically from those of most other weeds. Unlike most of them manuka is not an introduced species but a native, and through countless ages it has won itself a definite place in the vegetation of New Zealand. "This fact places manuka in a very different category from most other weeds It belongs to this country, and if disease wiped it out the eflect on the vegetation with which it has been so long in association might indeed be disastrous. "In summarising the position four important conclusions have been reached: —

“Manuka serves a most useful purpose on vast areas of poor country by promoting forest regeneration and reducing soil losses and run-off. “Where it is economic, good farming is the most effective means of preventing manuka invasion, and the - blight cannot be considered as an alternative. “The artificial propagation of a plant disease about which little is yet known is fraught with danger. "Though manuka blight might be of immediate advantage to some farmers, its widespread distribution is likely to prove disadvantageous to the country in the long run. "In the present state of knowledge it is considered unwise to foster and distribute the manuka blight,” the statement concludes, "and until the results of investigations now being made are available, farmers are urged, in their own interests dnd in the interests of New Zealand’s vegetation as a whole, to refrain from frying to use the blight beyond the range of its spontaneous occurrence."