Content Of Herbage Research Articles

Assessing metal transfer to vegetation and grazers on reclaimed pyritic Zn and Pb tailings.

A study of the concentrations of zinc and lead in an engineered soil capping system overlying sulphide mine tailings was undertaken. Tailings geochemistry, soil cover and vegetation were monitored over a 4-year period, and a cattle grazing demonstration exercise was conducted over a 1-year period. Whilst the tailings had a relatively high pyrite content and demonstrated oxidation, a circum neutral pH was observed for the duration of the study period due to the high dolomitic content. No evidence of metal mobility into the soil cover and vegetation was observed over the monitoring period. Relatively high Zn herbage content is attributed to the glacial till component of the soil cover. Similarly, no evidence of metal transfer to grazing cattle was observed through blood and tissue analysis with Zn content not significantly different from control animals. Pb tissue content was below limit of detection.

Seasonal and interannual variations in feeding station behavior of cattle: effects of sward and meteorological conditions

A feeding station is the area of forage a grazing animal can reach without moving its forefeet. Grazing behavior can be divided into residence within feeding stations (with bites as benefits) and movement between feeding stations (with steps as costs). However, relatively little information has been reported on how grazing animals modify their feeding station behavior seasonally and interannually in response to varying environmental conditions. The feeding station behavior of beef cows (Japanese Black) stocked on a tropical grass pasture (bahiagrass dominant) was monitored for 4 years (2010 to 2013) in order to investigate the association of feeding station behavior with meteorological and sward conditions across the seasons and years. Mean air temperature during stocking often exceeded 30°C during summer months. A severe summer drought in 2013 decreased herbage mass and sward height of the pasture and increased nitrogen concentration of herbage from summer to autumn. A markedly high feeding station number per unit foraging time, low bite numbers per feeding station and a low bite rate were observed in summer 2013 compared with the other seasons and years. Bite number per feeding station was explained by a multiple regression equation, where sward height and dry matter digestibility of herbage had a positive effect, whereas air temperature during stocking had a negative effect (R2=0.658, P<0.01). Feeding station number per minute was negatively correlated with bite number per feeding station (r=–0.838, P<0.001). It was interpreted that cows modified bite number per feeding station in response to the sward and meteorological conditions, and this largely determined the number of feeding stations the animals visited per minute. The results indicate potential value of bite number per feeding station as an indicator of daily intake in grazing animals, and an opportunity for livestock and pasture managers to control feeding station behavior of animals through managements (e.g. fertilizer application, manipulation of stocking intensity and stocking time within the day).

Improving ryegrass‐clover pasture dry matter yield and urea efficiency with gibberellic acid

The effects of spraying gibberellic acid (GA3) at 20 or 30 g ha(-1), with or without application of urea, on pasture dry matter (DM) yield, herbage nitrogen (N) concentration and feed quality were investigated in 2011 and 2012 for managed pastoral systems in New Zealand across a range of sites, in both autumn and spring. On the Waikato site (autumn and spring, 2012), and at all five sites in 2011, liquid urea applied with GA3 at 20 or 30 g ha(-1) consistently produced significantly higher pasture shoot DM yield, relative to liquid urea alone. Application of GA3 alone reduced feed quality by lowering metabolizable energy, crude protein and organic matter digestibility values. However, a reduced feed quality was not observed when GA3 was applied together with liquid urea. Liquid urea applied with GA3 also reduced total N and nitrate-N concentration in herbage, relative to liquid urea applied alone. Application of GA3 together with liquid urea provides an opportunity for the strategic use of urea to meet both production and environmental goals.

Determination of yield and nutrient quality of herbage in Giron Masa grazing reserve, Kebbi State

The study determined the crude protein content of herbage collected from Giron Masa grazing reserve, Kebbi State Nigeria. The herbage samples were collected by using 1.0m 2 wooden frame (quadrant). Fresh weight of three most occurring species and remaining other species was taken by the use of spring balance for dry matter determination. Analysis of the data using SAS (1988) package indicated that LDS produces the highest DM and ERS was the least. DM yield on the other hand was highest in EDS and lowest in LRS. From the chemical analysis, highest values of 13.3% and least value of 5.6% CP was obtained in ERS and LDS respectively. The CF content was higher during the LDS (32.4%) and least in ERS (25.8%). Other parameters as ash, EE, Ca and P content were also determined. The results of the study indicated a significant effect of season on nutrient content of range herbage. The nutrient contents of the herbage fall within the range considered normal for semi-arid environment. The significant seasonal effect on the quality of the feeds could also be considered normal for plants growing in the semi-arid environment. The dry matter yield data, herbaceous and ligneous species composition and nutrient quality obtained in the present study could be considered fair. This could hold optimum number of livestock with their nutritional requirements, especially during the growing season. Keywords; grazing reserve, herbaceous, ligneous, nutrient, species, yield,

Nutrient selection by dairy cows grazing chicory or perennial ryegrass during spring

Traditional measures of the nutrient concentration of herbage before grazing may not accurately depict the nutrient intake of grazing animals. An experiment was conducted to investigate differences in DM and nutrient intake, and milk production of lactating cows offered chicory- or perennial ryegrass-based diets during spring on a commercial dairy farm in south-west Victoria. This experiment was conducted in mid-lactation (spring), with chicory (Cichorium intybus L.), perennial ryegrass (Lolium perenne L.) and a mixed sward of chicory and perennial ryegrass offered at two daily allowances (nominally 20 and 30 kg DM/cow to ground level). Selection differentials for estimated metabolisable energy (MJ/kg DM), neutral detergent fibre (NDF; g/kg DM) and acid detergent fibre (g/kg DM) varied (P &lt; 0.05) with forage type, while allowance affected selection for estimated metabolisable energy, crude protein, acid detergent fibre and NDF (P &lt; 0.01). However, the differences in selection differentials observed between the chicory, mixed sward and perennial ryegrass under the same conditions indicated that preferential grazing for leaf rather than stem in chicory may affect nutrient selection in a way that differs from perennial grass species, resulting in much lower intakes of NDF than indicated by traditional measurements of feed characteristics.

Evaluating seasonal variation in mineral concentration of cool‐season pasture herbage

AbstractPasture herbage is a major source of minerals for livestock in pasture‐based production systems. Herbage mineral concentrations vary throughout the growing season, whereas mineral supplementation to livestock is often constant. The study objectives were to analyse the seasonal variation in herbage mineral concentrations in tall fescue [Schedonorus phoenix (Scop.) Holub]‐based pasture with regard to beef cattle mineral requirements and to create a statistical model to predict variation in herbage mineral concentrations across the growing season. Pasture herbage was analysed from 12 grazing systems in Virginia to determine its mineral concentration from April to October of 2008–2012. The pasture herbage, grown without fertilization, contained adequate macronutrient concentrations to meet the requirements of dry beef cows through the growing season and the requirements of lactating beef cows in April. Phosphorus supplementation appeared to be unnecessary for dry beef cows given adequate concentrations in pasture herbage. A model using month of harvest, soil moisture and relative humidity explained 75% of the variation in an aggregated mineral factor. The 90% prediction intervals indicated that N, P, K, S and Cu concentrations could be predicted within 1·35, 0·08, 0·80 and 0·07% and 3·83 mg kg−1 respectively. Prediction of herbage mineral concentrations could help to improve livestock health, reduce costs to producers and limit nutrient losses to the environment.

Relationship between soil and biomass chemical properties, herbage yield and sward height in cut and unmanaged mountain hay meadow (Polygono–Trisetion)

Little is known about the effects of either long-term cutting with herbage removal or no management on the nutritional status of Agrostis capillaris and Festuca rubra meadows. We asked how management affected soil and herbage chemical properties, herbage yield and sward height. The experiment with cutting (C) and unmanaged (U) treatments was undertaken from 1999 to 2009 in the Jizera Mts., Czech Republic. Soil and herbage samples were taken from 2003 to 2009.Potassium was the only nutrient for which the soil concentration decreased under the C treatment. Soil K concentration was 175 and 210mgkg−1 in the C and U treatments, respectively, in the last year of the experiment. Herbage yield as well as sward height were significantly higher in the unmanaged than in the cutting treatment in all years. Concentrations of P and K in the herbage biomass were lower in the cutting than in the unmanaged treatment, but concentrations of N were lower only in some years. Concentrations of Ca and Mg were not affected by the different treatments. A strong positive relationship between concentration in soil and herbage was recorded only for K.In contrast to K, ten years of contrasting management was too short a period to affect plant-available (Mehlich III) P, Ca and Mg concentrations, but it was long enough to affect herbage chemical properties and yield.

Historical arsenic contamination of soil due to long-term phosphate fertiliser applications

Archived samples from the Park Grass Experiment, established in 1856, were analysed to determine the impacts of long-term phosphate fertiliser applications on arsenic concentrations in soil and herbage. In plots receiving 35 kg P ha−1 annually (+P), topsoil As concentrations almost doubled from an initial value of ∼10 mg kg−1 during 1888–1947 and remained stable thereafter. The phosphate fertilisers used before 1948 contained 401–1575 mg As kg−1, compared to 1.6–20.3 mg As kg−1 in the later samples. Herbage samples from the +P plots collected during 1888–1947 contained significantly more As than those from the −P plots, but later samples did not differ significantly. Mass-balance calculations show that the increase in soil As can be explained by the As input from P fertiliser applications before 1948. The results demonstrate that the P fertilisers used on the Park Grass Experiment before 1948 caused substantial As contamination of the soil.

Effect of sewage sludge on metal content of grassland soil and herbage in semiarid lands

Utilization for agriculture is one of the main disposal methods for sewage sludge. Subirrigated pastures are close to settlements and under intensive usage. The objective of this study was to investigate the effects of sewage sludge on subirrigated pasture soil and plant metal concentrations, and the relationship between them. Activated sewage sludge was applied to surface grassland at 25, 50, 75, and 100 t ha^{-1} year^{-1} treatments for 2 years. The concentration of all metals in topsoil (0-20 cm) increased depending on application dosages, but only Zn concentration increased in subsoil (20-40 cm) consistently. While in the second year the concentration of topsoil diethylene triamine pentaacetic acid (DTPA) metals increased significantly, it decreased in the subsoil. The ratio of organic matter increased in topsoil, but decreased in subsoil compared to the control. Doses of sewage sludge of 25 and 50 t ha^{-1} did not increase the metal content of herbage. However, the herbage's Cu, Zn, Pb, and Cd content increased at 75 and 100 t ha^{-1} treatments in comparison with both lower doses and the control. Similar to the soil concentration, the Zn content of herbage increased proportionally with higher sewage sludge application doses. Topsoil DTPA-extractable Zn, Cu, and Pb concentrations were correlated to herbage Zn, Cu, and Pb content significantly and positively. In subsoil, only DTPA-extractable Cu concentration was correlated to herbage Cu content significantly and negatively (r = -0.53**). A 25 t ha^{-1} year^{-1} application of sewage sludge can be recommended as an organic fertilizer in semiarid subirrigated pastures, as it increases topsoil organic matter and results in a low concentration of DTPA-extractable and plant metal content.

Protein enrichment and digestion improvement of napiergrass and pangolagrass with solid-state fermentation

Napiergrass (Pennisetum purpureum Schumacher) and pangolagrass (Digitaria decumbens Stent) are two major forage grasses for cow feeding. They possess high yields and high regeneration properties. Inoculation of cellulolytic microbes on herbage could enhance the protein content of herbage and promote digestibility in chickens. Cellulolytic microbes were isolated from various sources and cultivated on napiergrass and pangolagrass with solid-state fermentation for protein enrichment and invitro digestion improvement.The fermented napiergrass and pangolagrass were used as the main protein source in chicken diets to assess the feasibility for non-ruminants feed. After a 42-day fermentation period, napiergrass showed higher protein contents (13.4-13.9%) than those of pangolagrass(11.1-11.7%). The invitro digestibility of pangolagrass increased from 5.29% to 20.4%, whereas that of napiergrass increased from 5.29% to 19.0%. The average feed conversion efficiencies of chickens were close to the traditional fodder using corn as the main ingredient. Inoculation of appropriate cellulolytic microbes to enrich protein content and improve invitro digestibility of herbage with solid-state fermentation for chicken feed is the prospective technique for agriculture, animal husbandry, and substantial management.

Micronutrient concentrations in common and novel forage species and varieties grown on two contrasting soils

AbstractWe investigated differences between forage species with regard to micronutrients that are essential to sustain livestock health. Five grasses (timothy, perennial ryegrass, meadow fescue, tall fescue and cocksfoot), three legumes (red clover, white clover and birdsfoot trefoil) and four forbs (ribwort plantain, salad burnet, caraway and chicory) were grown on one micronutrient‐poor/low pH soil and one micronutrient‐rich/high pH soil (outdoor pot experiment). In addition, six grasses (timothy, perennial ryegrass, meadow fescue, tall fescue, Festulolium hybrid and cocksfoot) and one legume (red clover) were field‐grown on the micronutrient‐poor soil. Of the twelve pot‐grown species, herbage of chicory, red clover and white clover generally had the highest micronutrient concentrations (maximum Co, Cu, Fe and Zn concentrations were 0·23, 9·8, 233 and 109 mg kg−1 DM, respectively), except for Mo, which was highest in the clovers (10·6 mg kg−1 DM), and Mn, which was highest in cocksfoot (375 mg kg−1 DM). Soil type had the strongest effect on plant Mo and Mn concentrations. We also investigated differences in micronutrients between varieties, but they were generally few and negligible. The results indicate that choice of forage species is of major importance for micronutrient concentrations in herbage and that soil type exerts a major effect through pH. Forage of chicory, red clover and white clover generally met the requirements of high‐yielding dairy cows with regard to most micronutrients; therefore, diversification of seed mixtures so as to include these species could increase micronutrient concentrations in forage.

The management of the transition from hay- to pasture-based diets affects milk fatty acid kinetics

As fatty acids (FA) may become included among the quality parameters setting milk prices, their variation during diet changes needs to be investigated. The aim of this work was to study the kinetics of milk FA during rapid or progressive transition from hay- to pasture-based diets. Two farms in the southwestern Alps were selected. The milk of five Valdostana Red Pie cows from each farm was analysed on days 0, 1, 2, 3, 5 and 7 (at day 1, pasture was introduced into the diet), and thereafter twice a week. Changes in the milk FA became significant after days 3 or 5. The FA from C4:0 to C18:0, C18:2n-6, C18:3n-3 and C20:0 became stable after day 5 for both transition types. The cis9-C18:1, trans10 + trans11-C18:1 and cis9trans11-conjugated linoleic acid (CLA) became stable 3, 16 and 16 days after the maximum pasture intake, respectively. The C4:0 peaked at 3 days after pasture introduction or increase in the diet, probably reflecting high butyrate production in the rumen due to the high carbohydrate concentration in fresh herbage. The kinetics of all FAs fitted a log-normal cumulate distribution (except for C4:0), but model coefficients did not differ between the rapid and the progressive transition. After diet transition, only cis9-C18, cis9trans11-CLA, C18:3n-3, the mono-unsaturated and poly-unsaturated FA, and the sum of CLA isomers increased faster in the rapid transition than in the progressive transition diet (higher a coefficients), because of the higher initial pasture intake. Knowledge of the kinetics of milk FA when pasture is introduced into the diet could help farmers to improve milk nutritional quality.

Gypsum amendment of alkaline bauxite residue – Plant available aluminium and implications for grassland restoration

An inherent property of bauxite refining residue is high pH and associated elevated levels of solubilised aluminium. High solubilised Al content of the residue can inhibit plant growth and under natural conditions significant reduction of aluminium levels is extremely slow. Various procedures have been employed globally to reduce the alkaline properties of bauxite residue. At the Aughinish Alumina Ltd. refinery gypsum is applied as an amendment to reduce pH and sodicity of the residue for restoration. An additional benefit of this procedure is a significant decrease in plant available Al in the residue and low herbage concentrations. Furthermore, deficiencies of nutrients such as Ca, a symptom of Al toxicity, are not evident. To avoid excessive Al uptake in restored residue it is recommended that adequate calcium and other nutrients are added to the residue and nutrient cycling is encouraged as part of the restoration programme.

E-Cow: an animal model that predicts herbage intake, milk yield and live weight change in dairy cows grazing temperate pastures, with and without supplementary feeding

This animal simulation model, named e-Cow, represents a single dairy cow at grazing. The model integrates algorithms from three previously published models: a model that predicts herbage dry matter (DM) intake by grazing dairy cows, a mammary gland model that predicts potential milk yield and a body lipid model that predicts genetically driven live weight (LW) and body condition score (BCS). Both nutritional and genetic drives are accounted for in the prediction of energy intake and its partitioning. The main inputs are herbage allowance (HA; kg DM offered/cow per day), metabolisable energy and NDF concentrations in herbage and supplements, supplements offered (kg DM/cow per day), type of pasture (ryegrass or lucerne), days in milk, days pregnant, lactation number, BCS and LW at calving, breed or strain of cow and genetic merit, that is, potential yields of milk, fat and protein. Separate equations are used to predict herbage intake, depending on the cutting heights at which HA is expressed. The e-Cow model is written in Visual Basic programming language within Microsoft ExcelR. The model predicts whole-lactation performance of dairy cows on a daily basis, and the main outputs are the daily and annual DM intake, milk yield and changes in BCS and LW. In the e-Cow model, neither herbage DM intake nor milk yield or LW change are needed as inputs; instead, they are predicted by the e-Cow model. The e-Cow model was validated against experimental data for Holstein–Friesian cows with both North American (NA) and New Zealand (NZ) genetics grazing ryegrass-based pastures, with or without supplementary feeding and for three complete lactations, divided into weekly periods. The model was able to predict animal performance with satisfactory accuracy, with concordance correlation coefficients of 0.81, 0.76 and 0.62 for herbage DM intake, milk yield and LW change, respectively. Simulations performed with the model showed that it is sensitive to genotype by feeding environment interactions. The e-Cow model tended to overestimate the milk yield of NA genotype cows at low milk yields, while it underestimated the milk yield of NZ genotype cows at high milk yields. The approach used to define the potential milk yield of the cow and equations used to predict herbage DM intake make the model applicable for predictions in countries with temperate pastures.

The evaluation of endophyte toxin residues in sheep fat

AIM: To monitor changes in concentrations of lolitrem B and epoxy-janthitrems in the fat of sheep grazing perennial ryegrass infected with wild-type- and AR37-endophyte, respectively, during the time of year when ryegrass staggers would be expected to be observed. METHODS: Ten 5-month-old lambs with no previous exposure to endophytes were grazed on either wild-type (containing lolitrem B, n = 5) or AR37 (containing epoxy-janthitrems, n = 5) endophyte-infected perennial ryegrass (Lolium perenne L.) pastures between October 2008 and June 2009. Animals were regularly assessed for ryegrass staggers using the Keogh scale (0 = no signs, 5 = severe tremors). When a score of > 3.5 was observed animals were removed from the treatment pastures for 1 month. Fat biopsy samples were taken from each animal at approximately monthly intervals and analysed for endophyte metabolites using high performance liquid chromatography (HPLC) methods developed during this study. Regular herbage samples were also taken and concentrations of endophyte metabolites measured. RESULTS: Efficient and reproducible methods to analyse both lolitrem B and epoxy-janthitrems in fat were developed. Concentrations of lolitrem B and epoxy-janthitrems in herbage and in sheep fat increased from late November to peak in mid-February. Ryegrass staggers was observed in both groups of sheep at this time. Following 1 month of grazing non-infected pasture mean concentrations in fat of lolitrem B decreased by 43% from 61.8 to 35.3 ppb, and of epoxy-janthitrems by 38% from 1032.0 to 639.5 ppb. Maximum concentrations in herbage of epoxy-janthitrems (35.7 ppm) were higher than of lolitrem B (3.4 ppm), but signs of staggers were less severe in sheep grazing pasture containing the former compared with the latter (median Keogh scores in late February were 2 and 3, respectively), consistent with epoxy-janthitrems being low potency toxins. CONCLUSION: This study demonstrated that concentrations of epoxy-janthitrems and lolitrem B in sheep fat increased quickly during the initial phase of the study when concentrations in pasture increased, and decreased when animals were removed from pastures containing these compounds. These data will be used in the risk assessment of the endophyte metabolites.

Mineral Content of Lablab (Lablab purpureus L. Sweet) Herbage as Influenced by Phosphorus Application, Cutting Height and Age of Cutting at Samaru, Nigeria

As a result of the critical importance of herbage quality and danger of poor mineral nutrition of forage legumes that affect livestock feeds in Nigeria, this investigation was conducted. The experiment entailed field trials at Samaru, Nigeria over three wet seasons to evaluate the response of mineral composition of lablab (Lablab purpureus L. Sweet) herbage to phosphorus application and cutting treatments. The treatments were composed of factorial combinations of four rates of phosphorus application (0, 12, 24 and 36 kg P ha-1), two cutting heights (10 and 20 cm) as the main plot and four cutting ages (6, 12, 18 weeks and at maturity) as the sub-plot a in split plot design with three replications. Cutting lablab to a 10 cm stubble produced significantly higher calcium and phosphorus concentrations in the dry herbage than cutting to 20 cm. The Ca:P ratio in the herbage increased as age of cutting increased but cutting height did not influence this parameter. A phosphorus application rate of 12 kg P ha-1 produced the highest ash concentration in lablab herbage under a 12-week cutting regime. However, the highest phosphorus concentration of lablab herbage was produced with a zero phosphorus application rate under a cutting height of 10 cm. Under the first herbage cut, ash content increased significantly with age of cutting. It is beneficial to feed lablab herbage to livestock before crop attains physiological maturity. The nutritive value of the herbage determines the most appropriate time to feed lablab herbage to livestock.

The status and importance of crude protein and macro minerals in native pastures growing on Vertisols of the central highlands of Ethiopia

The effects of pasture management, season and soil nutrient status on crude protein (CP) and macro mineral concentration of native pasture was studied in the Vertisol areas of the central Ethiopian highland. Soil and herbage samples from 18 continuously grazed (CG) and 12 seasonally grazed (SG) pasture sites were analyzed for N, P, Ca, Mg, K and Na. Soil and dry season CG pasture samples were collected in January and February 2001 (dry season: November-February), while wet season CG and SG pasture samples were collected during September 2001 (wet season: April-October). The Potassium concentration (2.55%) of mixed herbage samples from SG pasture exceeded the K values (1.80%) from CG pasture (P<0.01). Significant (P<0.01) differences of CP and macro minerals concentrations were noted among forage species. The mean CP and K concentrations of herbage from CG pasture were higher (P<0.01) during the wet than during the dry season (5.97 and 1.80% vs. 3.18 and 0.79%), while the opposite was true for Ca (0.49% vs. 0.61%) (P<0.05). Regarding soil macro minerals and the corresponding herbage macro mineral concentrations, significant (P<0.05) but inconsistent correlations were found for Ca, P, Mg and Na. The results suggest that pasture management, season and to some extend soil nutrient status, can affect herbage CP and macro mineral composition. The levels of CP in CG pasture and that of P and Na in both CG and SG pastures may fall below the requirements of grazing livestock. Resting at critical stages of the growth cycle of the forage species encouraged the recovery of desirable species. For this reason resting of pasture can contribute significantly to the quality of the native pastures of the Vertisols of the central Ethiopian highlands and should be encouraged.

Simple prediction of crude protein content in vegetation growing on abandoned cultivated land

AbstractThe accuracy of two simple methods was compared for the prediction of crude protein (CP) content of above‐ground plant material of mixed‐species composition on abandoned cultivated land in Japan. The first method is based on standard CP values (in g kg−1 dry matter) for individual species (STV method) as listed in the literature. The second procedure (GLM method) was an application of the generalized linear model using the relative above‐ground biomass of monocots and legumes, total herbage mass, and day of year. Predictions were made at the quadrat scale, and for surveyed sites based on average of values for five or six quadrats in a single survey. A ‘leave‐site‐out’ method was adopted for model validation of the generalized linear model. The observed values of CP content ranged between 21·5 and 161·9 g kg−1 dry matter (DM). With the STV method, the values of root mean square error (RMSE indicates average estimation error) were 50·9 at the quadrat level and 53·8 at the surveyed‐site level (both g kg−1 DM). When a ‘leave‐site‐out’ validation was carried out, the RMSE‐values for the GLM method were 23·2 at the quadrat level and 13·2 at the surveyed‐site level (both g kg−1 DM). We therefore propose adoption of the GLM method for the purpose of estimating the CP content in herbage on abandoned sites.

Divergent Alfalfa Root System Architecture is Maintained across Environment and Nutrient Supply

Plant root system architecture can alter, and be altered by, soil fertility and other environmental conditions. We developed alfalfa (Medicago sativa L.) populations selected for tap‐ or branch‐rooted architectures and determined responses to P supply and K placement in field experiments. In Exp. 1, populations representing the parental composite and progeny from first and second cycles of divergent selection were seeded on soils testing low to medium for available P and K, a sandy loam (Becker, MN) and a silt loam (Rosemount, MN). Experiment 2 was conducted at Becker and included only second cycle progeny. Phosphorus was added to one‐half of the plots by injection of KH2PO4 (224 kg P ha−1) into the upper 40 cm of soil. On the other plots, equal K rates (270 kg K ha−1) as KCl were topdressed. Added P did not affect herbage dry mass in the first and second years following stand establishment, but increased herbage P concentration and uptake at Becker. There was no effect of K placement, but the tap‐rooted germplasm had lower K concentration in herbage than the parent. Although progeny did not differ in total root mass, the ratio of thickened‐to‐total root mass was larger below 30 cm for the tap‐rooted selection, which also produced more fine roots. Selected germplasms did not differ in P or K uptake. Selected root system architecture characteristics were expressed under, and apparently not modified by, growing conditions that covered three site‐years on two contrasting soils with differential P supply and K placement.

Forage herbs improve mineral composition of grassland herbage

AbstractProvision of an adequate mineral supply in the diets of ruminants fed mainly on grassland herbage can present a challenge if mineral concentrations are suboptimal for animal nutrition. Forage herbs may be included in grassland seed mixtures to improve herbage mineral content, although there is limited information about mineral concentrations in forage herbs. To determine whether herbs have greater macro‐ and micromineral concentrations than forage legumes and grasses, we conducted a 2‐year experiment on a loamy‐sand site in Denmark sown with a multi‐species mixture comprised of three functional groups (grasses, legumes and herbs). Herb species included chicory (Cichorium intybus L.), plantain (Plantago lanceolata L.), caraway (Carum carvi L.) and salad burnet (Sanguisorba minor L.). We also investigated the effect of slurry application on the macro‐ and micromineral concentration of grasses, legumes and herbs. In general, herbs had greater concentrations of the macrominerals P, Mg, K and S and the microminerals Zn and B than grasses and legumes. Slurry application indirectly decreased Ca, S, Cu and B concentrations of total herbage because of an increase in the proportion of mineral‐poor grasses. Our study indicates that including herbs in forage mixtures is an effective way of increasing mineral concentrations in herbage.