Cicer milkvetch (Astragalus cicer L.) is a promising forage legume, but little information is available on its forage production potential, particularly in mixtures with grasses. The objectives of these studies were to: (i) determine the compatibility of irrigated cicer milkvetch (CMV) with seven cool‐season grasses each planted in alternate rows, and (ii) compare the influence of three planting patterns on the compatibility of irrigated CMV with each of four cool‐season grasses. The seven grass species used in the first study were: smooth bromegrass (Bromus inermis Leyss.), meadow bromegrass (B. biebersteinii Roem. and Schult.), crested wheatgrass [Agropyron cristatum (L.) Beauv. ssp. pectinatum (Bieb.) Tzvel.], intermediate wheatgrass [Thinopyrum intermedium (Host.) Barkworth & Dewey], pubescent wheatgrass [T. intermedium ssp. barbulatum (Schur.)], tall wheatgrass [T. elongatum (Host.) Dewey], and creeping foxtail (Alopecurus arundinaceus Poir.). The grasses used in the second study were smooth bromegrass, meadow bromegrass, intermediate wheatgrass, and orchardgrass (Dactylis glomerata L.). The soil was a Nunn clay loam (mesic Aridic Agriustoll). Tall wheatgrass did not persist beyond the second harvest year. There was little, if any, difference among the other six grasses for compatibility with CMV because by the sixth harvest year the amount of CMV in the mixtures ranged from 76 to 83%. By the third harvest year, the legume content of the forage for the three planting patterns was similar and ranged from about 80 to 90%. Once established, CMV was very competitive with all cool‐season grasses and its forage yields alone and in grass mixtures were very similar to those of alfalfa.

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Cicer milkvetch (Astragalus cicer L.) is a promising forage legume, but little is known about its response to cutting. A 2‐year study was conducted at Fort Collins, CO, on a Nunn clay loam (fine, montmorillonitic, mesic Aridic Argiustoll) soil to compare yield, quality, and trends in carbohydrate reserves of cicer milkvetch and alfalfa (Medicago sativa L.) in response to annual three‐ and four‐cut clipping treatments. Quality was evaluated by determining concentrations of crude protein (CP) and cell wall constituents (CWC) in herbage from each harvest. Seasonal dry matter yields of alfalfa were similar under both clipping treatments during each year. Yields of cicer milkvetch were reduced under the more frequent cutting schedule in 1979, but not in 1980. During 1979, quality differences between the clipping treatments were apparent for alfalfa but not for cicer milkvetch. Improved quality, as measured by increased CP and decreased CWC concentrations, was observed in herbage from both species under the more frequent clipping treatment in 1980. Herbage CP concentration was simiilar under comparable clipping treatments during both years, however, the CWC concentration of cicer milkvetch was consistently lower than that of alfalfa. Cyclic trends in carbohydrate reserves were observed in alfalfa under both clipping treatments in 1980, but only under the three‐cut treatment in 1979. Carbohydrate reserve trends in cicer milkvetch roots and rhizomes were less cyclic than in alfalfa and similar under both cutting schedules each year. Carbohydrate reserve concentrations in all forage entries were similar at the end of the 1980 growing season regardless of clipping treatment. Following cutting, carbohydrate reserves in alfalfa were readily utilized during the initial period of recovery. Carbohydrate reserves in cicer milkvetch appeared to be actively involved in regrowth processes only when little, or no, residual leaf area remained after cutting.

Cicer milkvetch (Astragalus cicer L.) is a potentially valuable forage crop for irrigated pastures, but little information is available concerning the effects of management practices on forage production. Therefore, the objective of this field study was to evaluate the effect of six harvest treatments on yield, forage quality, weed invasion, and persistence of stand. The study was conducted under irrigation on a Nunn clay loam soil (aridic Argiustoll). The treatments consisted of clipping the forage two, three, four, five, six, and seven times annually for 3 years to a height of 7.5 cm. Forage yields and weed counts were taken for 3 years, and seven quality factors and four mineral elements were evaluated for 2 years. Total nonstructural carbohydrates in the rhizomes were measured at the end of the 3rd harvest year. There were significant differences in yield among harvest treatments in 2 of 3 years and for the 3‐year average. In general, the two‐ and three‐cut treatments were the most productive with 3‐year average yields of 10.5 and 10.7 metric tons/ha, respectively. Considerably more weeds were present in the five‐, six‐, and seven‐cut treatments than in the two‐, three‐, and four‐cut treatments. Annual weeds were most prevalent during the first 2 years, but by the 3rd year dandeloins (Taraxacum spp.) were the most common. Although there were significant differences among treatments for total nonstructural carbohydrates in the rhizomes, the differences were not associated with persistence because persistence of stands was excellent for all treatments. In vitro dry matter digestibility (IVDMD) and all chemical constituents evaluated, with the exception of magnesium and potassium, differed significantly among treatments each year. In general, cell wall constituents (CWC) and cellulose decreased with an increase in the frequency of cutting. Protein, IVDMD, and phosphorus increased as the number of cuttings increased. Lignin, hemicellulose, silica, calcium, magnesium, and potassium varied among cutting treatments. The quality of cicer milkvetch forage was high for all cutting treatments. Based on yield, quality, and stand persistence cicer milkvetch has the attributes of a desirable forage species.

The impermeable seed coat of cicer milkvetch (Astragalus cicer L.) restricts water imbibition and results in poor seed germination and subsequent stand establishment. Our objectives were to study the seed coat anatomy, areas of initial water imbibition, scarification effects on the seed coat, and the relationships between seed characters and percentage hardseed. Seed from 10 polycross progenies with a wide range of hardseededness (12 to 77% after scarification) were used. Scanning electron microscopy showed the following: the cuticle had a distinct faveolate pattern at the strophiole at magnifications of ✕ 125 and higher; the malpighian cells became longer and thinner as they neared the strophiole in comparison to the rest of the seed coat; the osteosclereids were shorter and wider at the seed tip in comparison to other sites on the seed coat; and the osteosclereids were not present at the hilum or the strophiole. In general, the seed coat anatomy was similar to that of small‐seeded legume species belonging to the subfamily Papilionoideae. The strophiole and seed tip accounted for 98% of the area of imbibition following mechanical scarification. The effect of mechanical scarification on the seed coat varied from no effect to small scrapes and indentations, large cracks, and complete removal. The strophiole accounted for 75% of the area of imbibition following H2SO4 (18.0 m0l H2SO4 L‐1) scarification. The effect of H2SO4 to the seed coat occurred in a distinctive pattern at the strophiole. The cuticle and exterior portions of the malpighian cells were dissolved, forming a circular cavity that had a large groove at its base. Percentage hardseed following mechanical scarification was correlated (P = 0.05) with seed length, width, volume, and weight (r = −0.91, −0.66, −0.88, and −0.82, respectively). Density was the only seed character that was significantly correlated (r = 0.70) with percentage hardseed following H2SO4 scarification. None of the seed characters were significantly correlated with natural permeability. Although the progenies did not differ for seed coat anatomy, it appears that selection can be made for increased permeability following mechanical scarification. Of the seed characters measured, weight would be the easiest to use when selecting for increased permeability.

The compatibility reactions of two diploid St alsike clover clones, 6–5 from the Danish variety ‘Otofte’ and 7–1 from an Ohio‐grown seed lot, were temperature‐sensitive in controlled environmental chambers. One to 2 days at constant 32 C changed the compatibility reaction of genotype 6–5 from self‐incompatibility to self‐compatibility. However, 2 to 3 days at 32 day‐27 C night temperatures were required to change the compatibility reaction of genotype 7–1. By the 4th day of treatment, 35 and 62% of the selfed florets were setting seed at the constant 32 C treatment for genotypes 6–5 and 7–1, respectively. Seed set for genotype 6–5 reached a high of 20% on the 5th day at the 32 day‐27 C night treatment; 11% of the florets set seed on the 4th day at the 32 day‐21 C night treatment; and a 4% seed set was reached on the 3rd day at the constant 27 C treatment. Genotype 7–1 did not respond to the 32 day‐21 C night and constant 27 C temperature treatments. After the compatibility reaction was changed at the high temperatures, propagules of the two genotypes were removed and placed at 21 C. The compatibility reaction of genotype 6–5 changed immediately to self.lncompatibility. However, 24 hr were required to change the compatibility reaction of genotype 7–1 from one of self‐compatibility to one of self‐incompatibility. The site of the change in the compatibility reaction for genotype 7–1 was the style, but it was not possible to locate the site for genotype 6–5.

Species used in range seedings must be relatively easy to establish in diverse environments. This study evaluated the ability of nine legumes to emerge and to become established from three depths of planting at five locations in the Central Great Plains. The nine species (Medicago sativa L., Onobrychis viciaefolia Scop., Vicia tenuifolia Roth., Coronilla varia L., A. stragalus cicer L., A, falcatus Lam., A. galegiformis L., A. striatus Nutt., and an unidentified Astragalus sp.) were seeded in the spring at 1.3‐, 2.5‐, and 3.8.cm depths. Seedling emergence counts were taken in early summer and stand ratings were made in late summer. Seedling emergence was best from the 1.3‐cm depth at all locations except one where the soil was very sandy and the best emergence was from the 2.5‐cm depth. In general, V. tenuifolia, M. sativa, A. falcatus, and O. viciaefolia gave better seedling emergence than the other five species over all depths of planting at all locations. Although V. tenuifolia gave the best average emergence, it is probably not adapted to the sandy soils of the region, because by late summer most plants had died at the two locations with sandy soil. Emergence of A. cicer was relatively poor, but because of its rhizomatous characteristic, the stand of A. cicer was fair to good at the 1.3‐ and 2.5‐cm depths at most locations by late summer. The small‐seeded entries, A. striatus and Astragalus sp., were very sensitive to depth of planting. Seedling emergence of A. striatus was poor at most depths and locations. Emergence of Astragalus sp., however, was fair to excellent at most locations at the 1.3‐cm depth. Emergence of the large‐seeded species, A. galegiformis and C. varia, was poor at all locations.

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