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Grasslands are valuable non‐crop habitats in the world's agricultural regions, providing more than simply forage for grazing domestic and wild animals. They provide refuge and resources that support high levels of arthropod biodiversity, most importantly for natural enemies that provide vital biological control services to the surrounding cropped landscape. Ideally, farmers could manage and manipulate grasslands to boost their biocontrol services, although to achieve this, knowledge of the ecological function of these habitats is essential. Unfortunately, grasslands are often bundled together with other habitat types, such as scrubland and forest, under the label 'non‐crop habitats', and little is known about the contribution that these specific habitats make towards landscape pest suppression. While recent research has been investigating the importance of other non‐crop habitat such as native vegetation remnants, the contribution that grassland habitats may make towards landscape pest suppression remains a significant knowledge gap in biocontrol research. Here, the current understanding of grassland habitats as biological control service providers in the world's mixed farming systems is reviewed. Limited research into whether grassland habitats support natural enemies, and thus contribute biological control services to the adjacent surrounding cropped landscape, has returned inconclusive, even conflicting, results. Potential explanations for this inconsistency are explored, including the lack of studies, inadequate estimates of predator impact and the variety of different grassland habitat types studied, including their diversity in composition and management practices. Conclusions drawn from these studies are discussed, and suggestions for management are recommended, including increasing grassland floristic diversity, limiting intensive management practices and implementing weed control. Future research directions are proposed, along with the need to develop a universal grassland classification system for research, management and conservation purposes, using grassland type, floristic diversity and management practices as key axes for classification. [ABSTRACT FROM AUTHOR]

Dorycnium hirsutum and D. rectum are perennial legumes which may have potential for use as pastures for the control of groundwater recharge in southern Australia. Little is known about the quality of the forage of Dorycnium species for grazing livestock or how these species respond to cutting. The effect of cutting height on plant survival, production of dry matter (DM), the proportion of leaf, edible stem (approximately <5 mm diameter) and woody stem in the DM and the nutritive value of the edible components was investigated. Biomass above five cutting-height treatments (uncut, ground level, 5–8 cm, 10–15 cm and 15–30 cm above ground level) was removed at 8-week intervals from plots of D. hirsutum and D. rectum from September 2002 to July 2003. In both species, plants subjected to lower cutting height treatments produced less DM above the height of the cut than those cut at higher heights. DM production declined over time in all treatments. Plants cut to ground level failed to regrow after the second harvest in D. hirsutum and the fourth harvest in D. rectum. Thus, these Dorycnium species were susceptible to high severity defoliations at 8-week intervals. Negligible inedible woody stem was present in regrowth of both species after 8 weeks but D. hirsutum regrowth had a higher proportion of leaf (0·72) than D. rectum (0·56). Plants left uncut accumulated a large proportion of inedible woody stem in the DM (0·69 in both species) by July 2003, particularly at the base of the plant. Edible DM from regrowth of D. hirsutum and D. rectum had crude protein (CP) concentrations of 120 and 150 g kg−1 DM; dry matter digestibility (DMD) values of 0·45 and 0·58; organic matter digestibility (OMD) values of 0·50 and 0·64; neutral-detergent fibre (NDF) concentrations of 370 and 290 g kg−1 DM; and acid-detergent fibre (ADF) concentrations of 260 and 210 g kg−1 DM, respectively. Medicago sativa, grown under similar conditions, had higher digestibility values (0·63 DMD and 0·66 OMD) and similar CP concentrations to D. rectum (140 g kg−1 DM), but higher concentrations of NDF and ADF (410 and 290 g kg−1 DM). Leaf material from both Dorycnium species had a higher nutritive value than edible stems, with DMD and OMD values of leaf of D. rectum being 0·68 and 0·74 respectively. Uncut plants had a much lower nutritive value of edible DM than the regrowth from cut treatments; older material was also of a lower nutritive value. The relatively low nutritive value of even the young regrowth of Dorycnium species suggests that forage quality is a major limitation to its use. Forage of Dorycnium species could be used during periods when other sources of forage are in short supply but infrequent grazing it is likely to produce forage of a low nutritive value. [ABSTRACT FROM AUTHOR]