Effects of gut treatment on recovery and germinability of bovine and ovine ingested seeds of four woody species from the Sudanian savanna in West Africa

Passage rate through the digestive tracts of zebu cattle and sheep, and subsequent germination of egested seeds of four woody species from the Sudanian savanna, Acacia dudgeoni, Acacia seyal, Burkea africana and Prosopis africana, were studied. The result indicates large differences in passage rate among woody species, as well as between animals. The values ranged from 46% to 87% for seeds ingested by cattle while the lowest passage rate was 2.3% and the highest being 74% for seeds ingested by sheep. Among plant species, seeds of Prosopis africana had the highest passage rate through the digestive tract of both cattle and sheep. Seed passage through the gut showed a significant positive correlation with seed mass and thickness for cattle and sheep, respectively. The gut treatment and the retention time in the gut did not improve germination capacity and the speed of germination of dormant seeds. For non-dormant seeds of Acacia dudgeoni, the germination capacity was higher for seeds ingested by cattle than sheep. The speed of germination was also significantly higher for egested seeds than the control. It can be concluded that large herbivores could play an essential role in long distance dispersal of seeds. Gut treatment alone was not effective in breaking seed coat-imposed dormancy, although it enhanced the rate of germination of non-dormant seeds. To get a complete picture of the effect of frugivore on the release of seed dormancy, the combined effect of initial mastication and subsequent gut treatment needs to be investigated.     

Major plants foraged by bees for honey production in Ghana: mapping of bee floral sources for the development of the apicultural industry

Abstract

Honey is increasingly being used as a food supplement and to treat various diseases and disorders in Ghana. Information on floral nectar preferences of foraging honeybees is, therefore, imperative to increase production to keep pace with demand. However, in Ghana, these floral nectar preferences are yet to be investigated and identified. This study was conducted to determine bee forage sources in the three main agro-ecological honey-producing zones of Ghana. Forty-eight unblended honey samples sourced from beekeepers were analysed. Pollen spectra of the honey samples revealed 27 different pollen types of which eight were identified to family level, while 15 and four were at the level of genus and species, respectively. The results also showed that, in general, 48% of the analysed samples were unifloral honeys with the most important pollen types coming from Sapotaceae/Meliaceae, Anacardiaceae and Burkea africana. Combretaceae, Sapotaceae/Meliaceae and Anacardiaceae, as well as Lannea-type and Burkea africana were found to be the most frequent (with occurrence greater than 50%) sources of nectar utilised by bees to produce honey. The predominant pollen sources of the honeys in the three main apicultural zones of the country were Sapotaceae/Meliaceae and Anacardiaceae (Forest zone), Sapotaceae/Meliaceae and Lannea-type (Savannah–Forest transition zone) and Sapotaceae/Meliaceae, Anacardiaceae and Gynandropsis gynandra (Savannah zones). Identification of the major bee floral sources can be used as a guide by beekeepers in the location of their apiaries as well as reforesting disturbed sites with these plants to act as sources of bee forage.     

Assessment of veld conditions with multivariate techniques in mixed bushveld,South Africa

The species composition of the herbaceous layer was surveyed in eight plant communities with a small-quadrat method. Ordination techniques were applied to these data to identify relative homogenous grazing areas, assess the veld condition of each unit and to identify indicator species, based on a grazing gradient. Five relative homogenous grazing areas were identified and should be treated as such for management purposes. The veld in the Nylsvlei Nature Reserve was generally in a good condition due to the low stocking densities of game (≈0.29 animals ha^?1) which have been maintained for many years. Nine indicator species, i.e. Cynodon dactylon, Digitaria eriantha, Ischaemum afrum, Leersia hexandra, Oryza longistaminata, Setaria sphacelata, Sporobolus ioclados, Sporobolus pyramidalis, and forbs, were identified which may be used for future monitoring of veld condition in the different vegetation units.     

Savanna trees in Namibia—Factors controlling their distribution at the arid end of the spectrum

This study reviewed the distribution of ten common savanna trees in Namibia. Tree distributions were investigated in relation to bioclimatic, topographic and edaphic variables at a national scale. The factors of importance at these broad geographic scales appeared to be rainfall, substrate and, likely, the incidence of frost. Baikiaea plurijuga, Burkea africana, Guibourtia coleosperma and Pterocarpus angolensis seem to reach their bioclimatic limits in Namibia.At the local level, plant traits become important and contribute to explaining distribution patterns. High water and/or nitrogen use efficiency (Acacia erioloba, Colophospermum mopane), dual water obtaining strategies (Faidherbia albida), fire tolerance (e.g. Acacia species, Burkea africana and Pterocarpus angolensis) and drought tolerance (Boscia albitrunca) are some key attributes providing additional explanations for current distributions.Amongst the selected trees and at broad geographic scales, below-ground adaptations are governed by rainfall regime in combination with coarse-textured soils, whereby shallow-rooted trees prevail in the Kalahari sandveld. Deep-rooted species are found largely on non-sandy soils. Physiological performance of many trees appears to be directly linked to rainfall regime and trees may hence show varying performance throughout their distribution range. Insight into plant functional attributes of trees in Namibia is required to develop appropriate management strategies in the light of climate change. Modelling climate change impacts should consider the relative contribution of bioclimatic versus local environmental factors that explain the current distribution patterns of the selected trees.     

Successional patterns of woody plants in catchment areas in a semi-arid region

Patterns of woody plants dispersal in a semi-arid nature reserve situated in Eastern Transvaal, South Africa, revealed that trees have spread from core areas and converted previously open grasslands to densely vegetated woodlands. These patterns were found in catchment areas of the gently undulating terrain which characterizes the region.Two plant communities dominated by Acacia senegal-Acacia tortilis and Euclea divinorum-Acacia nilotica were distinguished. Analysis of nearest-neighbour distances, dispersal patterns of seedlings and mature woody plants identified successional processes. These were manifested through intra and interspecific competition among the dominant tree species. Within each plant community, a transition of relative abundance was occurring namely, A. senegal became dominant in areas previously dominated by A. tortilis while E. divinorum was replacing previous A. nilotica dominance.Comparative assessment of the two plant communities was facilitated by the summary of competition and seedling dispersal indices in a multivariate analysis. Results indicated that tree species had characteristic dispersal strategies. Identification the patterns of woody plants establishment could advance the evaluation of successional dynamics and management of savannas in areas prone to bush encroachment.     

Seed weight patterns of Acacia tortilis from seven seed provenances across Botswana

Laboratory‐based seed storage systems have been developed as an alternative to in situ conservation for indigenous woody plant species. However, interactions between seed quality and environmental variables must be known for each species prior to seed collection, storage and sowing to ensure effective conservation. This study investigated Acacia tortilis seed weight/quality patterns across seven Botswana seed provenances in relation to: soil nutrient status, altitude; latitude; slope angle; % grass cover; height and density of other woody plants nearby. The higher rainfall and relatively eutrophic seed provenances of north‐western Botswana (Chobe, Okavango and Makgadikgadi) were associated with large A. tortilis species and seeds, as well as higher densities of woody plants. Spatial variation in seed weights of A. tortilis was principally a function of rainfall and soil organic carbon. Although more work is required to establish the relationship between seed weight and germination rates for A. tortilis, this research suggests that seed collection should focus on sites with high levels of rainfall and soil organic carbon.     

Alleviation of Salinity-Induced Dormancy in Perennial Grasses

All seeds of Aeluropus lagopoides and Urochondra setulosa germinated under non-saline conditions except for Sporobolus ioclados which showed only 40 % germination. Increase in salinity substantially inhibited germination and few seeds germinated at 400 mM NaCl. Germination at 200 mM NaCl was alleviated in U. setulosa by the application of gibberellic acid and fusicoccin, in A. lagopoides by thiourea, betaine, kinetin, fusicoccin and ethephon, and in S. ioclados by gibberellin and ethephon. High salinity (400 mM NaCl) induced germination inhibition was alleviated by proline, kinetin, fusicoccin and ethephon only in A. lagopoides.     

Ectomycorrhiza succession patterns in Pinus sylvestris forests after stand-replacing fire in the Central Alps

Fires shape fundamental properties of many forest ecosystems and climate change will increase their relevance in regions where fires occur infrequently today. In ecosystems that are not adapted to fire, post-fire tree recruitment is often sparse, a fact that might be attributed to a transient lack of mycorrhizae. Ectomycorrhizal (EcM) fungi play an important role for recruitment by enhancing nutrient and water uptake of their hosts. The questions arise whether and for how long the EcM community is transformed by fire. We investigated the resistance and resilience of EcM fungal communities on a chronosequence of 12 Pinus sylvestris stands in Valais (Switzerland) and Val d’Aosta (Italy) affected by fire between 1990 and 2006. Soil samples from burnt and non-burnt forests were analyzed with respect to EcM fungi by means of a bioassay. The number of EcM species was significantly lower in samples from recently (2–5 years) burnt sites than non-burnt forest, and increased with time since fire reaching levels of adjacent forests after 15–18 years. Community composition changed after fire but did not converge to that of non-burnt sites over the 18 year period. Only Rhizopogon roseolus and Cenococcum geophilum were abundant in both burnt sites and adjacent forest. Our data indicate fire resistance of some EcM fungal species as well as rapid resilience in terms of species number, but not in species composition. As long as the function of different EcM species for seedling establishment is unknown, the consequences of long-term shifts in EcM community composition for tree recruitment remain unclear.     

Growth features of Acacia tortilis and Acacia xanthophloea seedlings and their response to cyclic soil drought stress

Seedlings of Acacia tortilis (Forsk) Hyne and Acacia xanthophloea Benth. were raised under controlled glasshouse conditions. Control plants were watered daily while other treatments involved withholding water for 2, 4 and 6 days with 1‐day rehydration to container capacity. Compared to A. tortilis, A. xanthophloea seedlings showed higher leaf area, relative growth rates and total dry weight production under adequate water supply conditions. However, with increased water stress, A. xanthophloea seedlings could not alter their pattern of carbon allocation, retaining their root : shoot (r : s) ratio of about 0.5. By comparison, A. tortilis seedlings shifted carbon allocation to the roots, leading to a r : s ratio of 1.5 in water‐stressed seedlings, compared to 0.5 in the control plants. The ability of A. tortilis to reallocate carbon to the roots away from the shoots and to actually increase root growth compared to A. xanthophloea was a dehydration postponement strategy that may be important in species survival during drought.     

Growth response of woody species to elephant foraging in Mwea National Reserve,Kenya

The African elephant (Loxodonta africana) is known to greatly affect the structure and dynamics of vegetation. In Mwea National Reserve, elephants foraged mainly on Acacia ataxacantha and Grewia bicolor out of the five most preferred woody species. However, out of the five preferred woody species, only Grewia virosa and G. bicolor showed a positive association between their fresh use and past elephant use. All the five selected woody species showed high coppicing response after foraging, with the highest coppice growth rates recorded for Acacia brevispica and lowest for Grewia tembensis. The mean heights of woody species utilized by elephants were highest for A. brevispica and lowest for G. bicolor. The mean heights of coppices emerging after utilization by elephants were not significantly different for A. ataxacantha but were significantly shorter in the rest of the foraged species. Elephants avoided the coppices of many other woody species notably C. africana, A. tortilis, A. mellifera, Combretum aculeatum among others in the reserve. The objective of this study was to understand the capacity of woody species to recover after utilization by elephants and feeding response of elephants to new woody species re‐growth; a cycle that would define the dynamics of food resources and elephant population within the reserve.     

Land use,rangeland degradation and ecological changes in the southern Kalahari,Botswana

Dual‐scale analyses assessing farm‐scale patterns of ecological change and landscape‐scale patterns of change in vegetation cover and animal distribution are presented from ecological transect studies away from waterpoints, regional remotely sensed analysis of vegetation cover and animal numbers across the southern Kalahari, Botswana. Bush encroachment is prevalent in semi‐arid sites where Acacia mellifera Benth. is widespread in communal areas and private ranches, showing that land tenure changes over the last 40 years have not avoided rangeland degradation. Herbaceous cover is dominated in intensively grazed areas by the annual grass Schmidtia kalahariensis Stent and in moderately grazed areas by the perennial grass Eragrostis lehmanniana Nees. Nutritious perennial grass species including Eragrostis pallens Hack. Ex Schinz remain prevalent in Wildlife Management Areas. Other ecological changes include the invasion of the exotic Prosopis glandulosa Torr. and dense stands of Rhigozum trichotomum Kuntze. in the arid southwest. Regional patterns of wildlife species show that the expansion of cattleposts and fenced ranches has led to large areas of low wildlife conservation value even in areas where cattle production is not practiced. Findings show the need for integrated landscape‐scale planning of land use if the ecological value and biodiversity of the southern Kalahari is to be retained.     

Assessment of the bioregulatory activity of the leaf juices of higher plants in Al-Taif,Saudi Arabia against Fusarium solani,Phytophthora spp. and Rhizoctonia solani

Resistance to conventional fungicides causes poor disease control in agriculture. Natural products from plants have great potential as novel fungicide sources for controlling pathogenic fungi. In this study the antipathogenic activity of the leaf juices of 11 plant species (Chenopodium ambrosioides, Pulicaria vulgaris, Lavandula pubescens, Lavandula dentata, Ageratum conyzoides, Ficus retusa, Zizyphus nummularia, Acacia tortilis, Phragmanthera sp. Aff. Rufescens, Lawsonia alba and Olea europaea) were evaluated in vitro against three plant pathogenic fungi (Fusarium solani, Phytophthora spp. and Rhizoctonia solani). Plate assays showed that the leaf aqueous juices have antifungal activity against these fungi. The aqueous extracts of Pulicaria vulgaris, Lavandula dentata, Ageratum conyzoides, Ficus retusa, Zizyphus nummularia, Acacia tortilis, Phragmanthera sp. Aff. Rufescens (when associated with Acacia tortilis), Lawsonia alba and Olea europaea exhibited antifungal properties against Fusarium solani, Phytophthora spp. and Rhizoctonia solani with variable degrees. On the other hand, Chenopodium ambrosioides, Lavandula pubescens and Phragmanthera sp. Aff. Rufescens (when associated with Zizyphus nummularia) did not exhibit any fungitoxicity. All these observations suggest the possible exploitation of Chenopodium oil as a potential botanical fungitoxicant in ecofriendly control of post-harvest biodeterioration of food commodities from storage fungi.     

Composition and distribution of indigenous trees and shrubs as possible criteria for indicating adapted species in semi‐arid rangelands

This study assessed the composition and natural distribution of indigenous trees and shrubs as possible criteria for selecting suitable species for rehabilitation of degraded sites in semi‐arid rangelands. Study sites were identified at Nthangu, Kathonzweni and Kibwezi forests of Makueni County, Kenya using existing vegetation, agro‐climatic maps and Landsat imageries. The sites had mean annual rainfalls of 974 mm, 700 mm and 616 mm, respectively, and moisture indices of 49%, 35% and 32%. Data were collected by establishing sample plots and assessing species counts and diameters at breast height (DBH). Basal area, relative dominance, relative abundance, relative frequency and important value indices (IVIs) were computed for individual families and species at each site. The number of families, genera and species declined from Nthangu (33, 60, 77) through Kibwezi (30, 48, 70) to Kathonzweni (28, 42, 69). Corresponding mean basal areas were 16.7 m² ha^?1, 76.8 m² ha^?1 and 19.3 m² ha^?1. The families Combretaceae, Burseraceae and Mimosaceae were the most important and widely distributed. Based on ecological importance values, candidate species for rehabilitation of degraded sites at Nthangu, Kathonzweni and Kibwezi were Combretum molle and Acacia hockii; Combretum collinum, Commiphora campestris and Acacia tortilis; and Commiphora africana and A. tortilis, respectively.     

Differential climatic conditions drive growth of Acacia tortilis tree in its range edges in Africa and Asia

Premise

Tree growth is a fundamental biological process that is essential to ecosystem functioning and water and element cycling. Climate exerts a major impact on tree growth, with tree species often requiring a unique set of conditions to initiate and maintain growth throughout the growing season. Still, little is known about the specific climatic factors that enable tree growth in savannah and desert tree species. Among the global tree species, Acacia tortilis occupies one of the largest distribution ranges (crossing 6500 km and 54 latitudes), spanning large parts of Africa and into the Middle East and Asia.

Methods

Here we collected climate data and monitored Acacia tortilis tree growth (continuous measurements of stem circumference) in its southern and northern range edges in South Africa (SA) and Israel (IL), respectively, to elucidate whether the growth–climate interactions were similar in both edges.

Results

Growth occurred during the summer (between December and March) in SA and in IL during early summer and autumn (April–June and October–November, respectively). Surprisingly, annual growth was 40% higher in IL than in SA. Within the wide distribution range of Acacia tortilis, our statistical model showed that climatic drivers of tree growth differed between the two sites.

Conclusions

High temperatures facilitated growth at the hot and arid IL site, while high humidity permitted growth at the more humid SA site. Our results confer an additional understanding of tree growth adaptation to extreme conditions in Acacia's world range edges, a major point of interest with ongoing climate change.     

Interactions of Acacia raddiana with herbaceous vegetation change with intensity of abiotic stress

Theoretical models predict that the relative importance of facilitation and competition may vary inversely across gradients of abiotic stress. However, these predictions have not been thoroughly tested in the field, especially in arid and semi-arid environments. In this study, we evaluated how the net effect of Acacia tortilis subsp. raddiana (syn. A. raddiana) trees on the herbaceous species varies across a gradient of water stress in arid Tunisian ecosystems. Our results show that the influence of trees on the herbaceous stratum is beneficial. An Acacia tree improves the richness of herbaceous species around it by two to three times. The positive effect of Acacia raddiana on species composition is characterised in particular by a better development of some species of high pastoral value such as Cenchrusciliaris, Cynodon dactylon, Eragrostis papposa, Sisymbrium irio and Chenopodium album. We fitted the relationship between seasonal rainfall and the relative neighbour effect index, which varied across this gradient, to a linear model. Our results show that herbaceous plant cover, plant biomass, plant density and diversity are higher under a tree canopy and this positive interaction still increase with higher abiotic stress conditions.     

Joint use of habitat by red kangaroos and shorthorn cattle in arid central Australia

The distribution of cattle and red kangaroos among the major communities of a 170 km² paddock in central Australia was determined from 108 and 82 air surveys respectively over a four and a half year period. Fifty-nine surveys of each species were used in this report. Changes in use of the communities by the two species were analysed in relation to forage conditions using linear regression techniques. The two species showed trends in time of use of the open and wooded communities. Kangaroos used the mulga-perennial community (groved Acacia woodland with a shrub and perennial grass understorey) during good forage conditions and moved to the drought refuge open communities when forage conditions deteriorated. Cattle, on the other hand, used the open communities during good forage conditions and tended to move to the mulga communities and the hills when drought began. Mulga-annual (ungroved Acacia woodland with short grass and forb understorey) was the only major community which showed no clear linear relationship between kangaroo use and forage conditions. This might be a buffer area from which kangaroos come and go as other areas become more attractive as feeding areas. Cattle, however, show some preference for mulga annual during medium forage conditions. There appears to be little spatial interaction by the two species except during drought when kangaroos concentrate on the open communities and some cattle continue to feed in these communities. Community selection seems to be determined mainly by forage conditions, as there is no evidence that one species attracts or repels the other in spatial terms. In the conditions observed, the two species successfully coexisted with some control of numbers of cattle by man.     

Seed viability of five wild Saudi Arabian species by germination and X-ray tests

Our objective was to evaluate the usefulness of the germination vs. the X-ray test in determining the initial viability of seeds of five wild species (Moringa peregrina, Abrus precatorius, Arthrocnemum macrostachyum, Acacia ehrenbergiana and Acacia tortilis) from Saudi Arabia. Usually several days were required to determine the viability of all five species via germination tests. However, X-ray test will give immediate results on filled/viable seeds. Seeds of all species, except Acacia ehrenbergiana and Acacia tortilis showed high viability in both germination (96–72% at 25/15 °C, 94–70% at 35/25 °C) and X-ray (100–80%) test. Furthermore, there was a general agreement between the germination (19%, 14% at 25/15 °C and 17% and 12% at 35/25 °C) and X-ray (8%, 4%) tests in which seed viability of Acacia ehrenbergiana and Acacia tortilis was very low due to insect damaged embryo as shown in X-ray analysis. Seeds of Abruspreca torius have physical dormancy, which was broken by scarification in concentrated sulfuric acid (10 min), and they exhibited high viability in both the germination (83% at 25/15 °C and 81% at 35/25 °C) and X-ray (96%) tests. Most of the nongerminated seeds of the five species except those of Acacia ehrenbergiana and Acacia tortilis, were alive as judged by the tetrazolium test (TZ). Thus, for the five species examined, the X-ray test was proved to be a good and rapid predictor of seed viability.     

Determining spatio-temporal distribution of bee forage species of Al-Baha region based on ground inventorying supported with GIS applications and Remote Sensed Satellite Image analysis

In arid zones, the shortage of bee forage is critical and usually compels beekeepers to move their colonies in search of better forages. Identifying and mapping the spatiotemporal distribution of the bee forages over given area is important for better management of bee colonies. In this study honey bee plants in the target areas were inventoried following, ground inventory work supported with GIS applications. The study was conducted on 85 large plots of 50 × 50 m each. At each plot, data on species name, height, base diameter, crown height, crown diameter has been taken for each plant with their respective geographical positions. The data were stored, and processed using Trimble GPS supported with ArcGIS10 software program. The data were used to estimate the relative frequency, density, abundance and species diversity, species important value index and apicultural value of the species. In addition, Remotely Sensed Satellite Image of the area was obtained and processed using Hopfield Artificial Neural Network techniques. During the study, 182 species from 49 plant families were identified as bee forages of the target area. From the total number of species; shrubs, herbs and trees were accounting for 61%, 27.67%, and 11.53% respectively. Of which Ziziphus spina-christi, Acacia tortilis, Acacia origina, Acacia asak, Lavandula dentata, and Hypoestes forskaolii were the major nectar source plants of the area in their degree of importance. The average vegetation cover values of the study areas were low (<30%) with low Shannon’s species diversity indices (H′) of 0.5–1.52 for different sites. Based on the eco-climatological factors and the variations in their flowering period, these major bee forage species were found to form eight distinct spatiotemporal categories which allow beekeepers to migrate their colonies to exploit the resources at different seasons and place. The Remote Sensed Satellite Image analysis confirmed the spatial distribution of the bee forage resources as determined by the ground inventory work. An integrated approach, combining the ground inventory work with GIS and satellite image processing techniques could be an important tool for characterizing and mapping the available bee forage resources leading to their efficient and sustainable utilization.     

Relative densities and habitat utilization of non-utilized, terrestrial gamebird populations in a natural savanna, South Africa

The objective of this study was to determine the relative population densities and habitat utilization of gamebird species in relation to plant communities, the amount of ecotone, and vegetation structure. The distribution of five terrestrial gamebird populations was monitored for 12 months in the Nyslvley Nature Reserve, South Africa. Only three species, Swainson's francolin (40.44% of the total gamebird population), crested francolin (10.41%) and guineafowl (43.94%), were found in significant numbers. Group sizes of these gamebird populations were typical for the species. The high amount of edge or ecotone (total amount of edge (DI) = 0.26), the short (9.36 cm) and evenly structured grass layer (mean Foliage Height Diversity (FHD) = 0.38), and a mosaic of open areas and termitaria thickets rendered the Sporobolus ioclados–Acacia tortilis Savanna suitable for gamebirds. The adjacent seasonally inundated floodplain was also utilized to some extent, mainly by Swainson's francolin. It appears that visibility is more important for gamebirds than a high diversity in grass structure. Also, a mosaic of feeding areas and cover makes an area suitable for terrestrial gamebirds. Of the gamebird species found in the reserve, only the Swainson's francolin, crested francolin and guineafowl populations had the potential to be harvested.     

Invasion of Euryops floribundus in degraded South African communal grassland: Unpacking the invasion relationship with elevation,soil properties,the quality and quantity of the herbaceous layer

Shrub invasion is a recent occurrence in African grassland ecosystems. This study assessed the distribution of Euryops floribundus (a native shrub species) along an elevation and invasion intensity gradients, and its relationship with soil and herbaceous vegetation in a South African grassland. Shrub density increased (p < 0.05) from the uplands (2,301 plants/ha) to the bottomlands (4,888 plants/ha). Themeda triandra (a highly palatable grass) was dominant at the uplands and sloping sites, whereas Eragrostis plana and Sporobolus africanus (poorly palatable grasses) dominated the bottomlands. Upland soils had the highest organic carbon (OC), phosphorous (P), calcium and nitrogen (N) contents, but the lowest shrub density and herbaceous biomass. Canonical correspondence analysis indicated that elevation, soil OC and N contents determine important vegetation variables along the elevation gradient. In the shrub density gradient, soil P, OC and N responded positively to E. floribundus density. Grass biomass in the moderate and heavily invaded sites was high, but the abundance of palatable grasses declined, suggesting that E. floribundus invasion may be concomitant with a decrease in rangeland condition in terms of quality forage provision.