Keeping Up-To-Date With Pasture Topping

Bay of Plenty Beacon, Volume 16, Issue 35, 20 December 1950, Page 4

Keeping Up-To-Date With Pasture Topping

(By W. H. Mandeno)

Whilst the weather holds for haymaking there is little time for tidying up the odd seedhead in grassed pastures. With greater use of tractor mowers, however, it is becoming more common to keep up to date with topping. Although it is sometimes carried out for the sake of tidiness, or because Californian Thistles require it, topping is generally done with the aim of increasing leaf production. This is due to common recognition of the greater palatability and digestibility of leafage than seedhead. When the plant is at the stage of its growth cycle of sending up seedheads it has previously stored the required nutrients in its root system—in much the same way as “rooterops” do. After the formation of seeds many species- die whilst others, including perennial grasses, enter a -resting stage to enable them to withstand adverse weather conditions. In Poverty Bay it is unusual to have such regular summer rainfall as, in the Bay of Plenty, enables continued pasture growth. Where such growth can be expected it pays to use all ways to prolong the growth cycle and to this end topping can help. In dry areas the pasture is generally overgrassed with consequent rating of seedheads, but under better management only a limited area is treated so harshly and controlled grazing allows more length and then more growth so long as moisture is retained in the surface layers of the soil. Such pastures may need a trim to make the most of their controlled grazing. • l { It is often considered that topping is dangerous in dry weather. By baring the soil the loss of moisture is regarded as being hastened, but this may be debated. A topping mower should be set high enough to clear the bulk of the feed and what is cut off should have plenty of sail cover beneath it. It does not require much cover by a growing sward for evaporation losses to be actually superseded in importance by that “transpired” by the grow-, ing plant. With the widespread adoption of extensive grazing based on electrified fences the pastures have been longer when fed off. This has meant that the longer grass around animal droppings has appeared to be out of hand. It seems to depend largely on the worm population and soil fertility as to whether suchclumps of grass need trimming. Where decomposition is rapid thei clumps will be eaten' down satisfac-