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The use of silvopastoral systems improves the sustainability of resources, enhancing the efficiency of the production system, with potential to offer local and global ecosystem services. The objective of this study was to evaluate the persistence of Andropogon grass (Andropogon gayanus cv. Planaltina) in nine years of growth and the ingestive behavior of goats under continuous stocking in a silvopastoral system during the rainy season, in comparison to the monoculture. The treatments were two production systems: monoculture (Andropogon grass) and silvopastoral system—SPS (native trees mixed with Andropogon grass). The persistence was evaluated between the years of 2011 and 2019 and, the ingestive behavior was evaluated in the grazing periods of 2019 (March, April, May and June). No effect of the interaction between cultivation systems and years was found on forage dry mass yield (P = 0.17) and leaf/stem ratio (P = 0.21), however, the forage dry mass yield was higher (P < 0.01) in the silvopastoral system. There was effect of interaction on the crude protein content (P < 0.01). In addition, there was effect of the different systems on the NDF content (P < 0.01). There were no significant differences (P > 0.10) for the ingestive behavior variables, except for the bite mass that was higher in the monoculture. Significant differences were found for the bite rate, with a mean value of 17.8 bites/min−1. The DM intake in relation to the body weight was equivalent to 2.86% of the BW. There was no difference in the variation of the mean body weight of the goats between the cultivation systems of Andropogon grass. The Andropogon grass pasture grown in monoculture system and SPS remains perennial for nine years of grazing. Goat grazing in the two cultivation systems of Andropogon grass showed similar performance. [ABSTRACT FROM AUTHOR]

The study investigated the nutritive composition as well as acceptability of ensiled roughages comprising Andropogon gayanus (AG), maize husk (MH), maize stover (MS) and their mixtures in equal proportion with Tephrosia bracteolata (TB) by West African Dwarf (WAD) sheep. Seven treatment diets were formulated comprising AG: 100% Andropogon gayanus, MH: 100% maize husk, MS: 100% maize stover, TB: 100% Tephrosia bracteolata, AG + TB: 50% Andropogon gayanus + 50% Tephrosia bracteolata, MS + TB: 50% maize husk + 50% Tephrosia bracteolata, MS + TB: 50% maize stover + 50% Tephrosia bracteolata. The experiment was completely randomized in design. Significant variations were observed in the chemical composition of the plant materials before and after ensiling. It was revealed that Tephrosia bracteolata, prior to ensiling, had the highest crude protein (CP) content, lowest crude fibre (CF), neutral detergent fibre (NDF), acid detergent fibre (ADF) and acid detergent lignin (ADL). Similar trend was observed in the chemical composition of Tephrosia bracteolata after ensiling. Inclusion of Tephrosia bracteolata in the roughages improved their nutritional quality. All the silage treatments presented good physical characteristics. The acceptability of the silage by 12 WAD sheep ranked thus: TB > MS + TB > AG + TB > AG > MS > MH + TB > MH. Silage digestibility was highest (66.60%) in TB, closely followed by MH + TB (62.67%) and least in MS. It was concluded that WAD sheep production could be enhanced by feeding ensiled maize plant residues alone or in combination with Tephrosia bracteolata during the lean season. [ABSTRACT FROM AUTHOR]

The objective was to evaluate the characteristics of the pasture and the behavior of grazing goats under continuous stocking in a silvopastoral system (SPS) of Andropogon grass (Andropogon gayanus Kunth cv. Planaltina) in comparison to its monoculture (MC). The treatments consisted of two cropping systems: monoculture of Andropogon grass and silvopastoral system—SPS of native trees mixed with Andropogon grass, evaluated in five grazing periods using goats (February, March, April, May and June). Pasture height, leaf/stem ratio and the dry mass of forage, leaf, stem and dead material were evaluated. The grazing behavior of the goats was also assessed. Significant effect of interaction was observed (p < 0.05) on pasture height and on the dead material dry mass yield of the pasture among cropping systems and grazing periods. There was a significant effect of the different systems (p < 0.05) on the yield of forage dry matter, leaf dry matter and leaf/stem ratio. The SPS presented superior grazing time (p = 0.01), with an average of 389.0 min. Regarding rumination and moving times, there was no difference between cropping systems and grazing periods (p > 0.05). The Andropogon grass has the potential to be used in SPS with grazing goats under continuous stocking, positively affecting the pasture and animal behavior. [ABSTRACT FROM AUTHOR]

Grasses are amongst the most abundant and environmentally damaging invasive weeds worldwide. Biological control is frequently employed as a sustainable and cost-effective management strategy for many weeds. However, grasses have not been actively pursued as targets for classical weed biological control due to a perceived lack of sufficiently specialised and damaging natural enemies to use as biological control agents. There are also concerns that the risk posed to economically important crop/pasture species and closely-related native species is too great to consider implementing biological control for invasive grasses. In this paper, we review the literature and demonstrate that grasses can possess suitably host-specific and damaging natural enemies to warrant consideration as potential biological control agents. The risk of grass biological control is no greater than for other weedy taxa if practitioners follow appropriately rigorous risk assessments protocols. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article concerning the introduction of elephants in Australia as a cost-effective way in controlling invasive gamba grass by David Bowman in the 2012 issue.

The author discusses the environmental problems facing Australia, with particular focus on wildfires and invasive species. He proposes the solution of introducing large herbivore mammals such as the elephant to Australian ecosystems, arguing that it would address both concerns through restabilizing the food chain, controlling flammable gamba grasses through grazing, and conserving threatened native species.