Zig-zag Clover May be of Value in Low-rainfall Areas

New Zealand Journal of Agriculture, Volume 94, Issue 2, 15 February 1957, Page 183

Zig-zag Clover May be of Value in Low-rainfall Areas

By

W. R. LOBB,

Assistant Fields Superintendent, Department of Agriculture, Christchurch

ZIG-ZAG (Trifolium medium) has been grown in New Zealand for many years, but is little known except to grassland research workers. It was recorded in Auckland Province in 1871, but attracted little attention until the work of Dr, L. Cockayne in the 1920 s resulted in its successful, establishment in trials on the Dunstan Range in Central Otago.

IN appearance zig-zag clover is very like red clover, having hairy leaflets and red florets, but unlike red clover it has extremely vigorous rhizomes. Its main value is its persistence and ability to survive and spread in a rigorous climate with low rainfall, though for satisfactory

growth fertilisers may be required. It responds readily to phosphates, lime, or molybdenum where these materials are deficient. Though not normally a high-yielding clover, under these conditions it is superior both in production and in persistence to any other perennial clover. It owes much of its persistence to its underground growth habit and ability to overwinter in a dormant state.

For this reason it has aroused the interest of grassland workers as a plant which may be of value in such areas as the Mackenzie Country and the depleted country of Central Otago.

Its usefulness may not be confined to such areas, however, as it could find a place on the lowlands where climatic conditions are too severe for the survival of red and white clovers. Its dormant habit and its ability to recover from underground roots could be an asset on the light gravelly plains which are exposed to drying winds in the low-rainfall areas.

The main weakness of zig-zag clover, which imposes a severe restriction on its practical utilisation, is that it is an extremely shy seeder. In the past seed has-been so scarce that many of the experimental plots of zig-zag clover laid down by the Department of Agriculture have been established by propagating plants from roots taken from

ZIG-ZAG CLOVER ... the original area in the Dunstan Range. Late in 1950 approximately 5 acres of zig-zag clover were located on the property of Mr. R. C. Ruddenklau, in the Tapui district in North Otago, and the performance of the plant in this area is of considerable practical interest. The age of the stand is not known, but it has possibly been there for some 20 to 30 years. During this time the area has been under cultivation on two occasions and it was recalled that the area was very difficult to plough doubtlessly owing to the mass of trailing, twitchy roots produced by

this clover. The cultivation periods most probably assisted the spread of the clover and by 1950 it was dominant on all but a few patches of the paddock; the whole stand may have been derived from only a few plants. This stand gives some indication of the behaviour of zig-zag clover in a pasture sward. The paddock was a mixture of white clover, zig-zag clover, and a trace of Montgomery red clover, with a good grass balance, dominantly cocksfoot and crested dogstail. Despite the massive roots of this clover, it did not choke out the white clover or the grass components of the sward and did not appear likely to do so. ’ Ziz-zag clover does not come away early in spring, and goes completely

below ground early in autumn, its maximum growth taking place from late November to early March. The grasses and white clover therefore have good growing periods . without competition, early and late in the season, which permit their survival. A portion of this paddock was closed in an endeavour to procure seed. This part was cut and harvested in February 1951 and from the time of cutting until the following November it made no growth above ground. After cutting, all top growth died back and the only way to secure evidence of its existence was to dig for the twitchy root mass. Where the area was not cut it did not die back as early, remaining above ground until winter. From November to January the production was good. It was slow to recover from heavy grazing, but grew well enough when growth restarted. A mob of 300 ewes and their lambs was used to control the growth in December and it carried them for 10 days. Under good growing conditions it made little recovery for a further 10 days and then it started away quite rapidly. The existence of this area enabled the Department to obtain a small amount of seed, about sjlb., which was utilised to evaluate the performance of the plant over a wider field than had previously been possible.

In recent years the Grasslands Division of the Department of Scientific and Industrial Research, realising the value of zig-zag clover in areas where hardiness is all important, has bred a strain with greater vigour and a much improved capacity for setting fertile seed. Seed of this strain is not yet available commercially.

A number of trials have been laid down by the Department of Agriculture in which the production and agronomic value of this new improved strain under harsh environmental conditions is being tested against other pasture legumes, such as white, red, subterranean, strawberry, and reversed clovers, alsike, lucerne, and Lotus uliginosus (major).

Work of Mt. Albert Research Station to be Demonstrated

A demonstration of the work of the ** Plant Diseases Division and Fruit Research . Station of the Department of Scientific and Industrial Research at Mt. Albert Road, Mt. Albert, Auckland, will be given from 25 February to 2 March, when the Station will be open to the public from 9 a.m. to 5 p.m. each day.

The display of Station equipment and exhibits and the explanations of the methods used to investigate all diseases attacking plants and plant products should be of particular interest to farmers, fruit growers, and

gardeners.