GRASS LANDS.

Press, Volume LXIV, Issue 19375, 30 July 1928, Page 6

GRASS LANDS.

SEEKING THE IDEAL. IMPORTANCE OF HABITAT.

Methods by which our iess fertile pasture lands can be made to carry the most productive pastures were explained by Mr E. B. Levy, agrostologist to the New Zealand Department of Agriculture, in a comprehensive lecture to the Canterbury Agricultural Science Club at Canterbury College on Saturday night. The title of the lecture was "Grass Land Habitats." Mr Levy denned the meaning of the term "habitat" as the sum total ot the influences combining to make up the growing-place in any particular locality. Soil fertility, temperature, light and shade, relative humidity, wind, and the work of man were ail very potent influences which modified habitat. Vegetation could be lniiuenced, for good or for evil, by the modification of the habitat. There was no succession of vegetation on an unstable habit, such as moving rock or sand,- but immediately these became permanent then came vegetation on it and a succession of plants. | There was no doubt that climate was j the chief influence on the habitat ot the mountain. As we came further

down in altitude the climate becann less severe, its influence less marked till on the level other factors share* the influence with climate. The lecturer went on to show, b? lantern slides, how one type of fores' displaced another, as the habitat wa; modified. For example, bracken gav( way to manuka, this in its turn to th< smaller forest trees, and they to th< bigger timber forests. Of course, thi; transformation was a matter of hundreds of years. These were the different kinds oi habitats on which attempts were beiiij made to establish grasslands, Mr Levy classified the differem types of grasslands according to then fertility. In his opinion the danthonia, which covered so many thousands of acres, especially of hill'country, was the original covering of New Zealand land hundreds of years ago, before the advent of the forest. Where I it grew there was no doubt fertility was poor. - 'Different conditions favoured different grasses. For instance, red clover demanded a different habitat from white, while lucerne would flourish on some soils and languish on others. Each species acted as an indicator. It the kind of habitat favouring each were . discovered, then, by changing the habitat to suit it, we could obtain the conditions under which it flourished best;, Mr Levy next traced the changes on any particular grass made by habitat. He showed'how cocksfoot flourished on one- side of a fence which was grazed only at intervals and not very hard, while on the other side, which was closely grazed, thus allowing the sun to get at the roots, the grass did not do we'll. The former was a cocksfoot habitat and the latter a non-cocksfoot one. The ideal habitat was where rye and white , clover dominated. Hence the other less favourable habitats should be so treated as to approximate to those where rye and white clover flour-" ished. These were found in drained fertile areas. In less fertile. land would be found cocksfoot, dogstail, along with white clover; in dry, infertile land ratstail, Chewing's Fescue, and New Zealand rice, and in barren lands, scab.. Thus all these could be so improved till they approximated to the habitat favourable for rye an(l white clover. Mr Levy added that along with this study must be taken that of improving "the strains of the grasses themselves. The composite study of these two problems was the means of getting the pasture which would make for the maximiim production.