A simple disc instrument for estimating herbage yield

Abstract

A simple instrument for estimating the yield of herbage from measurements of height has been tested in cutting and grazing experiments. The instrument consists of a verticle graduated shaft and two linked aluminium discs which settle on the herbage. The height of the discs from the ground is recorded. Highly significant relationships were established between the yield and the height of herbage. Linear regressions explained 80–90% of the variation in the cutting experiments, and 39–62% in the grazing experiments. The errors attached to the estimated yields were high, but, because of the simple construction, low cost and rapid operation of the instrument, it is concluded that it has many useful functions in grassland research and management.

Comparing mobile and static assessment of biomass in heterogeneous grassland with a multi-sensor system

“…2014, respectively). Swards of the latter two stocking rates showed similar USH levels in both years, although pastures were managed and monitored by the use of a compressed sward height meter (CSH; according Castle, 1976), maintaining levels at 6 cm (moderate), 12 cm (lenient) and 18 cm (very lenient) (Wrage et al, 2012). This disparity may indicate the influence of sward structure on the conducted measurement methods: while CSH reflects the resistance of biomass according to stem density and sward height (Hakl et al, 2012), USH predominantly detects protruding objects regardless of other sward conditions in subordinate layers (Fricke et al, 2011).…”

Isotopic composition of soil, vegetation or cattle hair no suitable indicator of nitrogen balances in permanent pasture

“…The data is equal to 3.1 ± 0.5, 1.9 ± 0.3 and 1.1 ± 0.1 LU ha -1 during the grazing season for MC, LC and VLC, respectively). The CSH was measured weekly with a rising plate meter (Castle 1976;Correll et al 2003) and the stocking density adjusted accordingly. The grazing season lasted from May to October, usually interrupted by intervals in July or August when the animals had to be removed from the plots due to insufficient sward productivity.…”

Meralarda Farklı Otlatma Yoğunluklarının Bastırılmış Ot Katı Yüksekliği ve Ak Üçgülün (Trifolium repens L.) Görülme Sıklığına Etkisi

“…Orta otlatmada hedef bitki örtüsünün yüksekliğinin 6 cm, hafif otlatmada ise 12 cm olması amaçlanmıĢtır. Ot katı yüksekliği haftalık olarak diskmetre ile tespit edilmiĢtir (Castle 1976). Hedef yükseklik hayvan baskısı ile uyumlu hale getirilmiĢtir.…”

“…Otlatma mevsiminin baĢlangıcından itibaren 4-5 haftalık dönemler halinde sabitlenen ölçüm hatlarında gözlemler yapılmıĢtır. Her bir gözlem noktasında bastırılmıĢ ot katı yüksekliği (boyu) (Compressed sward height= CSH) Rising plate meterDiskmetre ile Castle (1976)"a göre ölçülmüĢtür. Bu ölçüm aleti ile bitki kompozisyonunun karĢı koyma gücüne, yoğunluğuna ve yüksekliğine göre, hareketli, 200 g ağırlığında, 30 cm çaplı metal kısmı ile dik bir Ģekilde bitki kümesi üzerinde bastırılarak, birimlendirilmiĢ sopası üzerinden bastırılmıĢ ot katı yüksekliği ölçülmüĢtür.…”