Factors limiting pasture production

R.W Brougham

Grasslands Division, D.S.I.R., Palmerston North

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Proceedings of the New Zealand Society of Animal Production. 1961, 21: 33-46

Data are presented which suggest that the maximum growth rate of pure stands of different species is determined by the amount of chlorophyll exposed to light of an intensity above 400 to 500 foot candles. From this a further limit to dry matter production is shown to be set by the growth form of species, and the shape and orientation of leaves in the light-absorbing canopy.

Comparisons made between the maximum annual yields of pasture and different crop rotations show little difference between pasture yields and the highest yielding crop rotations.

Results are presented showing the effect of various management practices on the yield, growth rate, and leaf growth of pastures. These results are discussed in terms of alterations of the light climate of pastures, the reduction in yields below potential yields being explained in part by incomplete utilization of light by the foliage of pastures.

Suggestions are made of ways of increasing both the potential production of dry matter per unit area of land, and the conversion of this energy into edible foods.

Keywords: NZSAPAB;