Earth’s land cover consists of forests, agricultural land, urban settlements and a large, heterogeneous category that includes deserts, grasslands, savannas, shrublands and tundra. This heterogeneous category has eluded a collective designation comparable to that of forests, which has contributed to its omission from multilateral programs and critical global initiatives. Potential designations for this land category – drylands, grasslands, grassy biomes, open ecosystems and rangelands – were evaluated for their relative advantages and disadvantages. Grassy biome is recommended as the most appropriate designation because it conveys a meaning that is distinct from forests, emphasizes that grasses often coexist with other plant growth forms and has great utility for use by multilateral organizations. However, the criteria of tree canopy cover >10% used by the Food and Agriculture Organization (FAO) to define forests represents a major obstacle to implementation of the grassy biome designation. This minimal canopy cover infringes on global savannas that occupy 20–25% of global land area. An assessment of the functional plant traits determining the shade and fire tolerance of savanna and forest trees indicates that a minimal tree canopy cover of 45% represents an ecologically appropriate demarcation between savannas and forests.

Humans depend heavily on nature. Drylands are home to 2.5 billion people, but the extent to which nature contributes to people (NCP) in drylands has been little explored. We examined the global contribution of nature to people, aiming to compare drylands and non-drylands. We predicted a lower contribution in drylands than non-drylands, largely because of the sparser population densities (peoples’ needs) and more degraded status of natural resources (lower potential contribution). Consistent with expectation, nature’s contribution was about 30% lower in drylands, with significantly lower values for drylands in Asia, Oceania, Africa and South America, but no difference for Europe and North America. Differences were due mainly to lower contributions from material and regulating contributions, i.e., the regulation of air quality, climate, water quantity and flow, soil protection and the supply of woody material, and potentially, lower use by people in drylands. Predicted declines in rainfall and increasing temperature are likely to place increasing pressure on nature to contribute to human well-being in drylands. A better understanding of nature’s contributions to people would improve our ability to allocate limited resources and achieve sustainable development in drylands.

South African lovegrass (Eragrostis plana Nees) is the most important weed of native pastures in southern Brazil. Management options are limited under water-stress conditions, and glyphosate has been the main tool for control. This study compared four salts of glyphosate applied at three growth stages and determined the glyphosate tolerance level. In addition, the performance of ammonium sulfate (AMS) under two soil moisture conditions (50% and 100% of water-holding capacity) and the effect of AMS on absorption and translocation of radiolabeled [14C]glyphosate were evaluated. The potassium salt of glyphosate had the fastest activity across growth stages of E. plana, which is more vulnerable to glyphosate at the panicle initiation stage. Isopropylamine salt was the slowest-acting glyphosate formulation. Younger plants were typically more easily controlled than older plants at the full tillering stage. The addition of AMS increased the level of control of drought-stressed E. plana compared with glyphosate alone by increasing translocation out of the treated leaf and consequently increasing the concentration of glyphosate in the primary culm. These data can be used to plan an effective management program for E. plana that takes into account the developmental stage of desired pasture grass species.

Herbage allowance (HA) management during gestation–lactation cycle of cows grazing native grasslands improves pregnancy rates and calves’ weaning weight records. Those improvements were associated with greater herbage mass, and better body condition score (BCS) and metabolic status of the cows, which could affect grazing and maternal behaviour, particularly when temporary suckling restriction (TSR) and flushing (FL) is applied. The objective of this study was to evaluate the effect of HA during the gestation–lactation period on cows’ and calves’ liveweight (LW), BCS, milk yield, insulin, IGF-1 and leptin concentrations, as well as the proportion of diurnal grazing activities (grazing, ruminating, walking and idling), and maternal behaviour from −10 to 70 days relative to TSR (day 0 = initiation of TSR at 86 ± 10 days relative to calving). Thirty-three primiparous Hereford cows were allocated to HA treatments during gestation and lactation, which annually averaged 2.5 (low = LHA) and 4 kg DM/kg LW (high = HHA). The LW and BCS of cows did not differ during −10 to 50 days but were greater in HHA than LHA at the end of the study (P < 0.05). Concentrations of IGF-1 were greater in HHA compared to LHA, while insulin and leptin did not differ. Grazing was lower in HHA than LHA, and the opposite occurred with ruminating and idling (P < 0.05). Cow–calf physical distance was greater in LHA cows compared to HHA (P < 0.05) and increased greatly in the former group after FL, while this increase was lower and later in HHA cows. Milk yield was greater in HHA (P < 0.05), and calves’ weight did not differ between treatments from day −10 to 35, but was greater in HHA compared to LHA from 45 days until the end of the study. Thus, the HHA in a low herbage height and mass condition resulted in greater IGF-1 concentrations and milk yield, and induced changes in grazing and maternal behaviour that were associated with increased cows’ LW, BCS and calves’ weight at the end of the study.

Exotic annual grasses such as medusahead [Taeniatherum caput-medusae (L.) Nevski] and downy brome (Bromus tectorum L.) dominate millions of hectares of grasslands in the western United States. Applying picloram, aminopyralid, and other growth regulator herbicides at late growth stages reduces seed production of most exotic annual grasses. In this study, we applied aminopyralid to T. caput-medusae to determine how reducing seed production in the current growing season influenced cover in the subsequent growing season. At eight annual grassland sites, we applied aminopyralid at 55, 123, and 245 g ae ha−1 in spring just before T. caput-medusae heading. The two higher rates were also applied pre-emergence (PRE) in fall to allow comparisons with this previously tested timing. When applied in spring during the roughly 10-d period between the flag leaf and inflorescence first becoming visible, just 55 g ae ha−1 of aminopyralid greatly limited seed production and subsequently reduced T. caput-medusae cover to nearly zero. Fall aminopyralid applications were less effective against T. caput-medusae, even at a rate of 245 g ae ha−1. The growing season of application, fall treatments, but not spring treatments, sometimes reduced cover of desirable winter annual forage grasses. The growing season after application, both spring and fall treatments tended to increase forage grasses, though spring treatments generally caused larger increases. Compared with other herbicide treatment options, preheading aminopyralid treatments are a relatively inexpensive, effective approach for controlling T. caput-medusae and increasing forage production.

Salt rabbitbrush [Chrysothamnus nauseosus (Pallas) Britt., ssp. consimilis (Greene)] and greasewood [Sarcobatus vermiculatus (Hook.) Torr.] grow slowly in early spring until mid to late May. They then begin a period of rapid growth, at which time susceptibility to foliar herbicides is probably greatest. Greasewood ceases rapid growth in mid June to early July, but salt rabbitbrush continues to grow rapidly until early August. Greasewood that resprouts after herbicide application has a longer rapid-growth period than shrubs in an untreated stand. An average leader length of 4 cm indicates that rapid growth of salt rabbitbrush is underway, and first opening of the flower buds indicates that rapid growth is over. Appearance of greasewood staminate spikes indicates that rapid growth has begun, and the first appearance of dried spikes indicates that growth has ceased. Simultaneous control of these shrubs with a single application of phenoxy herbicides may only be possible during the relatively short period when both are growing rapidly. This period may only occur from late May to mid June in some stands and years, but may occur from mid May to early July in other cases.

Losses of picloram (4-amino-3,5,6-trichloropicolinic acid) in water exposed to sunlight ranged from 50 to 80% after 1 days' exposure (14 h sunlight) and 95% or more after 4 days exposure (56 h of sunlight) at four locations in Southern Arizona. Samples exposed at the highest elevation (2800 m) consistently lost picloram more quickly than samples at the lower elevations. Dry, recrystallized picloram losses were 11, 47, and 67% after 1, 2, and 4 days of sunlight exposure, respectively. At the same times, picloram losses in water were 65, 89, and 99%, respectively. These results indicate that photodecomposition is an important factor for the use and residue longevity of picloram on high-altitude rangelands of the western United States.

Shin oak is a deciduous shrub that forms dense stands of brush on sandy soils in rangeland areas of the Rolling and High Plains of Texas. Plant canopy reflectance measurements made on shin oak showed that it had both low visible (0.63- to 0.69-μm waveband) and nearinfrared (0.76- to 0.90-μm waveband) reflectance values, a characteristic generally not shared by associated plant species or mixtures of species. The low reflectance values of shin oak caused it to have dark-red, reddish-brown, or brown image tones on color-infrared photographic, videographic, and SPOT satellite images that made it distinguishable from associated vegetation and other land use features. The optimum time to remotely distinguish this noxious shrub is during the mature phenological stage from June to September. Computer-based image analyses of video and satellite images showed that shin oak populations could be quantified. This technique can permit “percent land area” estimates of shin oak on rangelands. The aerial imagery is useful for detecting shin oak on smaller rangeland areas, whereas the satellite imagery is applicable in mapping large areas of shin oak distribution.

Common and Drummond goldenweed are troublesome subshrubs that often invade rangelands in southern Texas. Both species produce a profusion of conspicuous golden-yellow flowers in the fall. Common goldenweed flowers from late September to mid-October, whereas Drummond goldenweed flowers from mid-November to early December. Plant canopy reflectance measurements made on both species showed that they had higher visible (0.63- to 0.69-μm waveband) reflectance than did associated plant species and bare soil during flowering. Flowering common and Drummond goldenweed plants had a yellow image on conventional color (0.40- to 0.70-μm) aerial photographs that made them distinguishable from associated plants and soil. Computer analyses of the conventional color film transparencies showed that common and Drummond goldenweed infestations could be quantified from associated vegetation and soil. Flowering common goldenweed plants could also be detected on conventional color aerial video imagery.

How to graze livestock sustainably is an important and complex question. The debate between rotational and continuous grazing has been ongoing since the 1950s, yet evidence is perennially mixed. We used scientometrics to understand the structure of science on Holistic Management (HM), the most contentious of these adaptive practices. We used papers in Web of Science since 1980 citing the work of HM's ‘father’, Allan Savory, as a way of delineating a field that is otherwise chaotic with terminology. Results show an increasingly diverse use of Savory's work geographically and in terms of subject areas. Taking a positive position on HM seems most likely for those doing farm-scale (rather than experimental) work in dry climates. Bibliographic factions align with the various disciplines working on grazing research and also their expressed opinion on HM practices. Factions represent disciplinary strength, suggesting barriers for integrative work but also the need for the resolution of competing understandings in specific contexts with diverse participants to inform grazing decisions.

Prescribed burning has primarily been used as a tool for the control of invasive late-season annual broadleaf and grass species, particularly yellow starthistle, medusahead, barb goatgrass, and several bromes. However, timely burning of a few invasive biennial broadleaves (e.g., sweetclover and garlic mustard), perennial grasses (e.g., bluegrasses and smooth brome), and woody species (e.g., brooms and Chinese tallow tree) also has been successful. In many cases, the effectiveness of prescribed burning can be enhanced when incorporated into an integrated vegetation management program. Although there are some excellent examples of successful use of prescribed burning for the control of invasive species, a limited number of species have been evaluated. In addition, few studies have measured the impact of prescribed burning on the long-term changes in plant communities, impacts to endangered plant species, effects on wildlife and insect populations, and alterations in soil biology, including nutrition, mycorrhizae, and hydrology. In this review, we evaluate the current state of knowledge on prescribed burning as a tool for invasive weed management.

Boundaries are technologies of power and knowledge that shape spatial and social realities and our understandings of them. This article examines the effects of boundary-making between Kenya and Ethiopia, and investigates the effects of borders on states of peace and conflict among Turkana, Samburu, Borana, Gabra, and Dassanetch of northern Kenya. If borders divide people, people benefit nonetheless from the environmental, social, and political entropy that borders generate by using the energy of spatial differences to advance their own individual and collective life projects.

Methane (CH4) emissions associated with beef production systems in northern Australia are yet to be quantified. Methodologies are available to measure emissions, but application in extensive grazing environments is challenging. A micrometeorological methodology for estimating herd-scale emissions using an indirect open-path spectroscopic technique and an atmospheric dispersion model is described. The methodology was deployed on five cattle properties across Queensland and Northern Territory, with measurements conducted during two occasions at one site. On each deployment, data were collected every 10 min for up to 7 h a day over 4 to 16 days. To increase the atmospheric concentration of CH4 to measurable levels, cattle were confined to a known area around water points from ~0800 to 1600 h, during which time measurements of wind statistics and line-averaged CH4 concentration were taken. Filtering to remove erroneous data accounted for 35% of total observations. For five of the six deployments CH4 emissions were within the expected range of 0.4 to 0.6 g/kg BW. At one site, emissions were ~2 times expected values. There was small but consistent variation with time of day, although for some deployments measurements taken early in the day tended to be higher than at the other times. There was a weak linear relationship (R2=0.47) between animal BW and CH4 emission per kg BW. Where it was possible to compare emissions in the early and late dry season at one site, it was speculated that higher emissions at the late dry season may have been attributed to poorer diet quality. It is concluded that the micrometeorological methodology using open-path lasers can be successfully deployed in extensive grazing conditions to directly measure CH4 emissions from cattle at a herd scale.

Disagreement exists within the scientific community with regards to the level of competition for feed between sheep and kangaroos in the Australian rangelands. The greatest challenge to solving this debate is finding effective means of determining the composition of the diets of these potential grazing competitors. An option is to adopt a non-invasive approach that combines faecal collection and molecular techniques that focus on faecal DNA as the primary source of dietary information. As proof-of-concept, we show that a DNA reference data bank on plant species can be established. This DNA reference data bank was then used as a library to identify plant species in kangaroo faeces collected in the southern rangelands of Western Australia. To enhance the method development and to begin the investigation of competitive grazing between sheep and kangaroos, 16 plant species known to be palatable to sheep were initially targeted for collection. To ensure that only plant sequences were studied, PCR amplification was performed using a universal primer pair previously shown to be specific to the chloroplast transfer RNA leucine (trnL) UAA gene intron. Overall, genus-specific, single and differently sized amplicons were reliably and reproducibly generated; enabling the differentiation of reference plants by PCR product length heterogeneity. However, there were a few plants that could not be clearly differentiated on the basis of size alone. This prompted the adoption of a post-PCR step that enabled further differentiation according to base sequence variation. Restriction endonucleases make sequence-specific cleavages on DNA to produce discrete and reproducible fragments having unique sizes and base compositions. Their availability, affordability and simplicity-of-use put restriction enzyme sequence (RES) profiling as a logical post-PCR step for confirming plant species identity. We demonstrate that PCR–RES profiling of plant and faecal matter is useful for the identification of plants included in the diet of kangaroos. The limitations, potential and the opportunities created for researchers interested in investigating the diet of competing herbivores in the rangelands are discussed.

An historical overview of human intervention in the natural environment of Crete is presented by considering trends in human population size as well as land-use records since the Neolithic period. Trends in human impacts over the last forty years are interpreted from available statistical data on human population, forests, rangelands, livestock and cultivated areas from 20 villages of the Psilorites Mountain area, central Crete. Depopulation occurred, mainly from 1961 to 1971, with migration to urban centres of Crete and abroad; this affected traditional land-use in the uplands and transformed the rural landscape. An increase of rangelands then occurred at the expense of forests, and human activities in agricultural lands intensified, through such as tree cultivation and irrigation. Livestock grazing has become a dominant activity on all wildlands with a dramatic increase in animal numbers (70.4% in sheep and 50.8% in goats recorded in 1992 as compared with 1981), attributable to European Union subsidies. This overstocking, coupled with frequent pastoral wildfires and uncontrolled grazing, has resulted in rapid changes of land-use systems and landscapes on Psilorites that now endanger the natural environment and resources.

We studied the response of vegetation and vertebrate assemblages to fire and grazing, and their interacting effects, in Eucalyptus woodland in north-eastern Australia. In this vegetation type, many pastures remain free of cattle grazing due to the occurrence of a native shrub poisonous to livestock. Vegetation (floristic data and 22 habitat variables) and vertebrate fauna (birds, mammals, reptiles) were sampled in 29 standardized 50 × 50-m quadrats in the 2001 wet season, representing four treatments: sites burnt recently (within 2 y) and grazed by cattle (4–8 ha per livestock unit); sites unburnt (last burnt >2 y ago) and grazed; sites burnt recently and ungrazed; and unburnt and ungrazed sites. Fire and grazing had a significant influence on vegetation: both grazing and fire reduced ground cover (fire in grazed sites 51–23%, fire in ungrazed sites 68–39%) and increased the cover of forbs (8% in burnt and grazed sites, 3% if ungrazed) and tussock grasses (20% in grazed and unburnt sites and 5% when ungrazed). Grazing caused a shift in floristic composition from the perennial hummock grass Trioda pungens to tussock grasses (e.g. Aristida spp., Enneapogon spp.), forbs (e.g. Phyllanthus spp.) and shrubs (e.g. Acacia spp.). Of the vertebrate groups, birds responded more to fire effects (9 species), reptiles to grazing effects (6 species) and mammals to the interaction (2 species). Species reacted to increases in bare ground (e.g. crested pigeon Ocyphaps lophotes, hooded robin Melanodryas cucullatus, Ctenophorus nuchalis) and to the dominant ground cover (e.g. Ctenotus pantherinus) or change in vegetation architecture (e.g. singing honeyeater Lichenostomus virescens, variegated fairy-wren Malurus lamberti). The clearest example of an interacting effect was the cycle of complementary dominance between the rodents Pseudomys delicatulus and P. desertor, the latter's post-fire recovery becoming more muted in sites where cattle grazed (modelled time for population recovery twice as long as in ungrazed sites).

The soil seed bank in a 5-y-old Sahelian fallow was studied through seed extraction and compared with germinations recorded either in controlled conditions, ex situ in a glasshouse, or in the field. The influence of phosphorus fertilizer and mulch application during the preceding crop period, and that of seasonal grazing regimes applied the last 2 y of fallowing, were assessed on the composition of the seed stock. Ctenium elegans, Fimbristylis hispidula, Merremia pinnata and Phyllanthus pentandrus accounted together for 75% of extracted seeds, 72% of ex situ, and 62% of in situ seedlings. Mulch treatment was correlated with the first axis of the canonical correspondence analyses performed on the seedling datasets. Mulch and phosphorus fertilizer treatments held similar responses, as they both favoured the seed bank of erect dicotyledons such as P. pentandrus and Cassia mimosoides. On the whole, the effects of grazing remained modest compared with the residual effects of past crop management practices. However, seedling densities increased as a result of dry-season grazing, while the soil seed bank decreased with wet-season grazing. Grazing also reduced the spatial heterogeneity of the seed bank rather than the overall number of species.

High livestock densities in rangelands can result in reduced animal production due either to overgrazing or reduced per caput food availability, yet evidence for reduced animal production due to overstocking is scarce. Here simple animal production models establish the occurrence of overstocking in a traditional agropastoral system in the Spiti Valley of the Indian Trans-Himalaya. Empirical data show that fecundity of adult female livestock is related to total livestock biomass density (S) as a negative linear function of S. Total herd production is modelled as a quadratic function of S, thereby calculating an optimum livestock biomass density (Sop), at which total herd production is maximized. A sample of 40 villages showed that over 83% of Spiti's rangelands may be overstocked with values of S > Sop. Overstocking seems to be a classic case of the tragedy of the commons, as livestock is individually owned while the land is communally grazed. Recent socio-economic changes have probably contributed to high levels of overstocking. Even areas within wildlife reserves are overstocked. Conservation management needs to focus on creation of grazing free areas and management of livestock densities.

A study was carried out in the dry season, from October 1993 to May 1994 at an institutional farm in Niono (14º5’N, 6ºE, 295 m), on the Sahelian border of Mali with a semi-arid climate. Thirty-four local Sahelian goats in their first to fifth lactation weighing about 27 kg were used. Eleven of them suckled twin and 23 suckled single kids. The does were herded on natural rangeland for 8 to 9 h/day and received no food supplements. Dry season forage mass, intake and nutritive value of diets selected by goats, milk yield and effects on kids’ growth were measured.

The vegetation cover consisted of a herbaceous stratum dominated by annual gramineae plants and a woody stratum composed of 26 species of plants, whose relative abundance varied according to the topography and soil type. The goats spent between 0·126 (early dry season) and 0·004 (late dry season) of grazing time on herbaceous cover and the remaining time on consuming leaves, flowers and fruits of woody plants. The phytomass decreased as the dry season advanced. However, nutrient intake was relatively constant during the course of the study period, as the goats compensated for low biomass by walking more and grazing larger areas and for longer periods. On average, goats selected diets with 121 g crude protein and 7·6 MJ metabolizable energy per kg dry matter.

The milk yield and milk fat were measured weekly for 29 weeks but data for only 12 weeks are interpreted and discussed. Mean daily actual and fat-corrected milk (40 g fat per kg milk) production for the first 12 weeks of lactation was 692 (s.e. 139) g and 627 (s.e. 73) g respectively. The milk yield was maximum in the 1st week of lactation followed by a gradual decline. Milk yield was affected by litter size, number of lactation, weight and age of does at parturition. The does with twin kids produced significantly more milk (762 (s.e. 110) g/day) than the does with singles (656 (s.e. 158) g/day) (P < 0·05). The milk yield increased from the first lactation (542 (s.e. 49) g/day) to the third lactation (739 (s.e. 49) g/day) (P < 0·05) with no difference between the third and fifth lactation. Does over 27 kg produced more milk than those under 27 kg (P < 0·001) and does over 2·5 years produced more milk than younger does (P < 0·01). Milk fat was inversely related to milk production. Kids born as singles were heavier (2194 (s.e. 76) g) than those born as twins (1966 (s.e. 78) g) (P < 0·05). The kid growth rate was affected by birth weight (P < 0·001) and milk yield of dams (P < 0·01). Within litter size (single or twins), sex had no significant effect on the growth rate of kids, however the singles grew faster than twins (P < 0·001) throughout the 12 weeks of measurement. Single kids were 1·41 times as heavy as twins at 12 weeks.

It is concluded that, the milk yield of does and weight gain of kids under the precarious feeding conditions of the study indicate that the local goats monitored were adapted to local harsh conditions. Nutrition has been regarded as the main constraint to goat production from the range in the dry season. Further specific studies are needed to overcome the dry season nutritional stress and to improve goat production.

Biological control of arthropod pests has a long history of useful practical application. Parasites, predators, and pathogens have been employed in many cases to control pest arthropods in an efficient, cost-effective, and permanent manner. The traditional tactics used in biological control (classical, augmentation, and conservation) remain vital and valuable tools in the biological control of pests for agricultural crops, range lands, forests, and glasshouses. New technologies offer promise. One emerging technique involves the genetic improvement of natural enemies of arthropods through selection, hybridization, or recombinant DNA technology.