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Simple Summary: Production of small ruminants, specifically hair sheep, has increased in recent years and has resulted in an increased presence of hair sheep in feedlots for finishing. In 2017, the United States banned the use of antibiotic growth promoters. This ban has resulted in an interest in non-medicated feed additives, such as yeast, to aid in growth promotion. While hair lambs tend to take longer to reach an adequate finishing weight, the utilization of a yeast fermentation product may aid as a natural growth promoter in the feedlot. Additionally, interest in grass-based finishing systems has grown, but there are limited data on using stored cool-season forages as the base of the diet. Based on the results of this experiment, the inclusion of a yeast fermentation product can improve the feedlot performance and carcass texture of hair lambs in a feedlot with an annual ryegrass-hay-based diet. Hair sheep production has increased in recent years, which has resulted in an increased presence in feedlots. Additionally, grass-based finishing systems for ruminant animal production have increased. Data are limited for finishing hair lambs on diets based on cool-season hay. The objective was to evaluate a Saccharomyces cerevisiae fermentation product (SCFP) on the feedlot performance and carcass characteristics of Katahdin lambs offered an annual ryegrass (Lolium multiflorum)-hay-based diet. Twenty-four Katahdin lambs (21.5 ± 2.5 kg BW) were assigned to either the control (CON) or the yeast-supplemented group (SCFP) in a completely randomized design. Lambs were offered a 14% crude protein total mixed ration diet based on annual ryegrass hay. The SCFP group also received the yeast supplement in their diet. Lambs in the SCFP group had a higher final body weight (p < 0.01) and ADG (p = 0.01). Less maximum and total energy were required to cut SCFP lamb meat compared to CON lamb meat (p < 0.03). Results from this study indicated that SCFP supplementation may prove to be beneficial in hair lamb finishing diets. Future research will need to specifically evaluate the use of these products in hair lambs with a larger sample size. [ABSTRACT FROM AUTHOR]

The article presents a study on alternative management options for multiyear perennial ryegrass seed production in Northern Minnesota. Topics include the use of plant growth regulators (PGRs) and fall residue management, such as open burning, baling, and mowing, to achieve multiyear seed production in northern climates.

Nitrogen enhances annual ryegrass (Lolium multiflorum Lam.) growth on the infertile Coastal Plain soils in the southeastern United States but N can be antagonistic to clovers. Nitrogen rate and time of application were evaluated on an arrowleaf clover (Trifolium vesiculosum Savi.)- annual ryegrass mixture growing on a Coastal Plain soil for 3 yr in northeast Texas. Fertilizer treatments were 0, 34, 67, or 101 kg N ha-1 at planting or first true clover leaf (FCL) stage followed by 0 or 67 kg N ha-1 in December and March. Planting, FCL, and December N applications enhanced ryegrass production but had little effect on arrowleaf clover production by mid March. The general trend was for clover percentage and yield to decrease and ryegrass yield to increase as the total amount of N fertilizer applied increased. The no-N treatment always had the greatest percentage clover usually followed by single N application treatments with clover percentages greater than 50%. Average annual yield of ryegrass alone without N was 1139 kg ha-1 compared to 4038 kg ha-1 with 201 kg N ha-1. Applying 67 kg N ha-1 at FCL and in December and March was always one of the most productive N treatments. Applying 67 kg N ha-1 only twice at FCL and in December was the best compromise for maintaining a high clover percentage and clover-ryegrass yield and was always equal to ryegrass alone with three appli- cations of 67 kg N ha-1. [ABSTRACT FROM AUTHOR]

Annual ryegrass (Lolium perenne L.) is an important cool-season forage grass in the southeastern US. Since large portions of soils in this region are too acidic for optimum ryegrass production, there exists an opportunity to use lime mud waste from numerous regional pulp and paper mills as an agricultural liming material. In this study, four lime mud application rates, 2.25 (L1). 4.51 (L2), 9.01 (L3), and 22.50 (l4) ton ha-1 dry weight basis, and a control (L0) were evaluated for response to ryegrass growth during the first 6 weeks to estimate an optimum application range over the testing soil for future field test. Results indicated that applied lime mud slowed ryegrass germination and seedling emergence, with differences of whole plant length among treatments L0-L4 significant only during the first three weeks. Differences of whole plant dry weight among treatments L0-L4 reduced thereafter. The initial soil pH increase due to the lime mud application dropped in treatments L1-L4 by the end of the 6-week experiment. The optimum lime mud application range was estimated between L2 and L3, which provided higher ryegrass yields (kg ha-1) of 84 and 80 over 77 of the control and complied with the Code of Federal Regulation, CFR 40 Part 503 for land application. [ABSTRACT FROM AUTHOR]

The article presents a study on the sensitivity of Magnaporthe oryzae isolates from perennial ryeglass to azoxystrobin systemic fungicide. The study involves 135 M.oryzae isolates gathered from golf courses in northeastern U.S. from 1995-2004. Several measures including medium components, temperature and incubation time were implied to highest degrees to figure out the sensitivity using in vitro spore germination assay. The results show zero difference between baseline and non-baseline isolates.

Many winter stresses affect the ability of a perennial grass to overwinter in cold, temperate climates. Freezing tolerance is one of the major component traits affecting winterhardiness. Although effective freezing tolerance assessment procedures have long been available for perennial ryegrass ( Lolium perenne L.), no work has been done to characterize plant collections in the United States that may possess novel variation for freezing tolerance and winterhardiness. In this study, 21 accessions sampled from a larger set of 300 accessions with known winterhardiness and 3 check varieties were subjected to environmentally-controlled, low temperature acclimation, followed by controlled freezing using a programmable laboratory freezer. Eight freezing treatments from −2 to −16°C were used to determine survival across the known spectrum of freezing tolerance in perennial ryegrass. LT50 values were estimated based on whole plant survival, as well as tiller survival at each of the temperature treatments in the evaluation. LT50 values for the accessions and checks ranged from −10.31 to −13.95°C, with 3 accessions possessing significantly greater freezing tolerance than the most freeze-tolerant check, ‘NK200’. LT50 values were well correlated with winterhardiness in St. Paul during the winters of 2004–2005 and 2005–2006. Lower LT50 values in this experiment were associated with greater spring growth following the stressful winter of 2004–2005 and upright growth habit. The lack of negative biological association between freezing tolerance and turf quality components indicates that freezing tolerance testing could be a useful tool in breeding and selection with landrace germplasm. [ABSTRACT FROM AUTHOR]

Gray leaf spot caused by Magnaporthe oryzae is a serious disease of perennial ryegrass (Lolium perenne) turf in golf course fairways in the United States and Japan. Genetic relationships among M. oryzae isolates from perennial ryegrass (prg) isolates within and between the two countries were examined using the repetitive DNA elements MGR586, Pot2, and MAGGY as DNA fingerprinting probes. In all, 82 isolates of M. oryzae, including 57 prg isolates from the United States collected from 1995 to 2001, 1 annual ryegrass (Lolium multiflorum) isolate from the United States collected in 1972, and 24 prg isolates from Japan collected from 1996 to 1999 were analyzed in this study. Hybridization with the MGR586 probe resulted in approximately 30 DNA fragments in 75 isolates (designated major MGR586 group) and less than 15 fragments in the remaining 7 isolates (designated minor MGR586 group). Both groups were represented among the 24 isolates from Japan. All isolates from the United States, with the exception of one isolate from Maryland, belonged to the major MGR586 group. Some isolates from Japan exhibited MGR586 fingerprints that were identical to several isolates collected in Pennsylvania. Similarly, fingerprinting analysis with the Pot2 probe also indicated the presence of two distinct groups: isolates in the major MGR586 group showed fingerprinting profiles comprising 20 to 25 bands, whereas the isolates in the minor MGR586 group had less than 10 fragments. When MAGGY was used as a probe, two distinct fingerprint types, one exhibiting more than 30 hybridizing bands (type I) and the other with only 2 to 4 bands (type II), were identified. Although isolates of both types were present in the major MGR586 group, only the type II isolates were identified in the minor MGR586 group. The parsimony tree obtained from combined MGR586 and Pot2 data showed that 71 of the 82 isolates belonged to a single lineage, 5 isolates formed four different lineages, and the remaining 6 (from Japan) formed a separate lineage. This study indicates that the predominant groups of M. oryzae associated with the recent outbreaks of gray leaf spot in Japan and the United States belong to the same genetic lineage. [ABSTRACT FROM AUTHOR]

Early weaning of calves (Bos spp.) increases pregnancy rates of beef cows; however, there is little information on nutritional management of the weaned calf on pasture. This research evaluated the effect of concentrate supplementation level on performance of early weaned (90 d of age) beef calves grazing annual ryegrass (Lolium multiflorum Lam.)-rye (Secale cereale L.) mixtures on Adamsville (uncoated, hyperthermic, Aquic Quartzipsamment) and Pomona (sandy, siliceous, hyperthermic Ultic Alaquod) sands. Three levels of supplement (10, 15, and 20 g kg-1 of calf body weight [BW]) were evaluated in a completely randomized design with three replicates. The concentrate contained 146 and 700 g kg-1 of crude protein (CP) and total digestible nutrients (TDN). Pastures were rotationally stocked with a 7-d grazing and 21-d rest period. Two calves were assigned as testers to each pasture, and additional animals were used to maintain a similar herbage allowance across treatments. There was no effect of concentrate supplementation level on herbage mass, accumulation, allowance, or nutritive value. Calf average daily gain (ADG; 0.74–0.89 kg), liveweight gain (LWG) per hectare (950–1320 kg), and stocking rate (SR; 5.5–6.5 animal units [AU] ha-1) increased linearly, and forage intake decreased linearly (18–11 g kg-1 BW) as concentrate rate increased. Grazing time was 284, 230, and 234 mind-1 (linear and quadratic effects) for the 10, 15, and 20 g kg-1 BW supplement treatments, respectively. Feeding systems with modest levels of supplementation (10 g kg-1 BW) of calves grazing cool-season grasses are practical options for early weaned calves during winter in the southeastern USA. [ABSTRACT FROM AUTHOR]

Systematic performance trials have been conducted in several states for more than 20 yr to evaluate agronomic performance of annual rye- grass (Lolium multiflorum Lam.). Despite development and testing of many annual ryegrass cultivars, the first improved cultivar, Gulf, has remained one of 10 to 12 cultivars recommended for planting in the southeastern USA. Our objectives were to evaluate cultivar yield performance across 12 yr at five locations, to assess cultivar yield distribution within growing seasons, and to estimate cultivar yield stability (consistency of relative performance environments). Efficacy measures were early-season yield (total before 1 March), late-season yield (total after 1 March), and total annual yield. Overall means for all cultivars and individual cultivar performance (for common years) were compared with Gulf or Marshall. Neither location effects nor cultivar × location interactions were found. Cultivar and year effects, plus cultivar × year interactions were detected (P < 0.05) for all three yield responses. Mean early season yields ranged from 2.3 to 4.6 Mg ha-1, with mean late-season yields ranging from 5.1 to 7.4 Mg ha-1. No trend existed for mean total yield relative to Gulf or Marshall to increase over time in association with availability of newer cultivars. Given large yearly fluctuation in yields, it is apparent that unpredictable environmental factors, including climate and perhaps pests, are the primary determinants of annual ryegrass performance rather than differences in yield potential among cultivars. Thus, yield stability may be an appropriate selection factor to include among the criteria for development of improved annual ryegrass cultivars. [ABSTRACT FROM AUTHOR]

Kentucky bluegrass (Poa pratensis L.) is often poorly established when sown in turfgrass seed mixtures with slender creeping red rescue (Festuca rubra L. ssp. litoralis Vasey) and perennial ryegrass (Lolium perenne L.), possibly because of its slow emergence and slow seedling growth. This study investigated the effect of sowing Kentucky bluegrass earlier than red fescue and perennial ryegrass on the botanical composition of the established turfgrass. In field experiments established during 2 yr, red fescue and perennial ryegrass were sown at weekly intervals from zero to 35 d [0-679 degree-days (°days) with a base temperature of 0°C] after Kentucky bluegrass had been sown in the same plot. Nine or twelve months after establishment, the botanical composition was estimated. When the species were sown simultaneously, Kentucky bluegrass only constituted 3 to 30% of the fillers, although the species constituted 50 to 59% of the viable seeds of the seed mixture. Delayed sowing of red fescue and perennial ryegrass significantly improved the establishment of Kentucky bluegrass, i.e., the percentage of tillers could be increased by up to 0.08% for every °day Kentucky bluegrass was sown before red fescue and perennial ryegrass. There was a corresponding negative effect on the percentage tillers of red rescue and primarily perennial ryegrass. In certain cases, the relationship between percentage tillers and difference in sowing time was better described by a nonlinear function, indicating an increasing effect when difference in sowing time was large. [ABSTRACT FROM AUTHOR]

Bermudagrass [Cynodon dactylon (L.) Pers x C. transvaalensis Burtt-Davy] greens across the southern United States are normally overseeded in the fall to provide a uniform green playing surface and tolerance to wear during winter bermudagrass dormancy. The spring transition from overseed grass back to bermudagrass is a major problem associated with overseeding because there can be a decline in putting green quality and playability. There have been recommendations, but relatively few published reports, on the effect of treatments associated with seedbed preparation and overseeding on bermudagrass spring transition. The objective of this 2-year study was to determine if spring transition of an overseeded 'Tifgreen' bermudagrass green was influenced by fall-applied scalping level, chemical, and seed rate treatments. Treatment factors and levels were designed to reflect the range of practices used by golf course superintendents in the region at the time of the study. The green was located in the Palm Springs, Calif. area, which has relatively mild winters and a low desert, southern Calif. climate. The first year of the study was from September 1996 to July 1997 and the second year was from September 1997 to July 1998. Scalping level treatments included a moderate and severe verticut and scalp; chemical treatments included a check, trinexapac-ethyl at two rates, and diquat; and seed rate treatments included a high and low rate of a mixture of 'Seville' perennial ryegrass (Lolium perenne L.) and 'Sabre' rough bluegrass (Poa trivialis L.). The plot was maintained under golf course conditions and a traffic simulator was used to simulate golfer traffic. Visual ratings of percent green bermudagrass coverage were taken every 3 weeks from 20 Feb. 1997 to 29 July 1997 and from 11 Nov. 1997 to 22 July 1998. Visual turfgrass quality ratings were taken during the second year of the study. Results showed that spring transition was not influenced by fall-applied... [ABSTRACT FROM AUTHOR]

Lolium multiflorumAgricultural and animal husbandry practices combined with soil composition have caused phosphate overloading of farmlands in different parts of the U.S. and Europe. Movement of soluble phosphates (P1) from phosphorus enriched soils results in degradation of natural aquatic systems, triggering serious environmental problems. Remediation of such sites using plants that tolerate and accumulate high concentrations of Pi in their aerial parts may be an attractive remediation technology. In the present study, Pi transport and accumulation potential of Marshall and Gulf ryegrass (Lolium multiflorum cultivars) were determined using a solution culture of seedlings. Ryegrass seedlings accumulated phosphorus (P) in excess of 2% of dry weight in their aerial parts when supplied with 5 g/L KH2PO4 in medium. Phosphorus accumulation was positively correlated with the concentration of phosphate (0-5 g/L KH2PO4) in medium. Plants grew well on medium containing 5 g/L KH2PO4, but concentrations above 5 g/L caused symptoms of toxicity. Scanning electron microscopy and energy-dispersive X-ray spectroscopy confirmed high P accumulation in different cell types of grass roots and shoots. Phosphate starvation and replenishment experiments point to the unique ability of these grasses to concentrate phosphate in the above-ground parts. It is hypothesized that the unique ability of these ryegrass cultivars may be due to the presence of efficient phosphate transport and sequestration mechanisms. [ABSTRACT FROM AUTHOR]

In California's Mediterranean type grasslands, native perennial grasses such as Nassella pulchra are surrounded by introduced annual species and these annuals are thought to have displaced natives through much of their range. Amongst other invaders, two grasses Lolium multiflorum and Bromus hordeaceus, commonly dominate portions of the grassland with potential for N. pulchra restoration. We hypothesized that competitor species differences and small-scale gaps (150 cm2) could be important determinants of N. pulchra survival and performance on these sites. Lolium multiflorum and B. hordeaceus were planted in 20 cm diameter circular plots at a constant rate of 1 seed per cm2 surrounding newly transplanted N. pulchra plants. Nassella pulchra showed no significant effect of the species of competitor or from the distribution of the competitors. Both interspersion of patches of bare ground and separation of competitors into patches did not increase N. pulchra pre-dawn water potential, basal area change, number of seeds produced, or average weight of seeds. The presence of L. multiflorum was associated with a decrease in N. pulchra survival compared with plots with only B. hordeaceus. Plants with increases in basal area of less than 0.75 cm2 during the growing season had 74% mortality compared with no mortality in plants with more growth. However, initial N. pulchra plant size was not a good predictor of mortality. Limiting competition from annuals may increase survival of N. pulchra plantings, but 60% of the plants survived for at least 1 year, despite being transplanted into soil containing substantial annual grass seed. [ABSTRACT FROM AUTHOR]

Annual ryegrass (Lolium multiflorum Lam.) is an important crop grown on approximately 1.1 million hectares in the southeastern United States. Used primarily for winter grazing, ryegrass has considerable yield variation among production areas, possibly due to differences in ryegrass response to the range of soil properties encountered in Louisiana. The objectives of this research were: (i) to evaluate variation in soil nutrient status among a range of soil series; and (ii) to compare yield, mineral uptake, and livestock nutritional value of annual ryegrass grown on these soils. Two replicated greenhouse studies were conducted to evaluate two cultivars of annual ryegrass, Gulf and Rio, grown in seven distinct soils collected from throughout Louisiana. Soils were unamended and received no additional fertilizer during the studies. Each study was harvested twice for yield and nutrient uptake determinations. Plant tissue samples were analyzed for potassium (K), calcium (Ca), iron (Fe), magnesium (Mg), manganese (Mn), zinc (Zn), and copper (Cu) concentrations using atomic absorption spectrophotometry. There were no cultivar differences or cultivar by soil interactions for yield or nutrient uptake. Yield and nutrient uptake of K, Ca, and Mn, were affected by the soil used. None of the soils produced ryegrass with sufficient Ca to meet the requirements of a dairy cow (Bos taurus), even though several of the soils had adequate to high soil test levels of Ca. All of the soils produced ryegrass with adequate Mg for beef cows (B. taurus; Bos indicus), but only half provided adequate Mg for dairy cows. All soils produced forage that met the beef cow Zn requirement, but only six provided adequate Zn for dairy cattle. All soils produced ryegrass with enough Mn to meet the requirements of both beef and dairy cattle, but there were large variations among the forages grown on the seven soils. These results indicate that mineral supplementation for beef cattle fed ryegrass grown on these soils might not be essential, but mineral supplementation for dairy cattle would be necessary. #Approved for publication by the Director of the Louisiana Agricultural Experiment Station as manuscript no. 02‐09‐0176. [ABSTRACT FROM AUTHOR]

Abstract Annual ryegrass (Lolium multiflorum Lam.) is grown on more than one million ha in the south-eastern USA each year. Recommended and actual seeding rates vary substantially within the region. The objective of this study was to evaluate variation in seed weight, germination, seedling vigour and seasonal yield performance among annual ryegrass cultivars. During 1997, 1998 and 1999, seed from fourteen commercial cultivars was weighed and germinated to determine numbers of pure live seed (PLS) m-2 before yield evaluation at four locations. Seed from ten cultivars was planted at 0·7 and 2·0 cm depth in a greenhouse study to evaluate relative seedling vigour. Cultivar mean single-seed weight ranged from 2·4 to 4·8 mg in 1997, 1·8 to 4·5 mg in 1998, and 2·6 to 4·6 mg in 1999. Seed germination ranged from 78·8% to 98·0% in 1997, 82·3 to 98·3% in 1998 and 77·8 to 98·3% in 1999. Seed number, PLS m-2 , ranged from 675 to 1289 in 1997, 710 to 1550 in 1998, and 717 to 1179 in 1999. Among the ten cultivars evaluated for seedling vigour, seedling weight differed between planting depths and a significant cultivar by year interaction was observed. Seedling weight was highly correlated with seed weight at each seeding depth. The effect of increasing number of PLS m-2 on subsequent yield performance, although small, was consistently negative. These results indicate that target plant populations may be obtained more economically by adjusting seeding rates for seed size differences among cultivars and seed lots of annual ryegrass. [ABSTRACT FROM AUTHOR]

Rotten plants, incomplete stands, a reduced number of shoots and a decline in dry matter yield were observed after hibernations of perennial and Italian ryegrass. Isolations from damaged plants showed that the main pathogen was the causal agent of snow mould Monographella nivalis (Schaffn.) E. Mull., asexual stage Gerlacbia nivalis (Ces. ex Sacc.) W. Gams et E. Mull., synonym Fusarium nivale Ces. ex Sacc. The following fungi were also isolated: Laetisaria fuciformis (Me Alp.) Burds., synonym Corticium fuciforme (Berk.) Wakef., Gibberella avenacea Cook, asexual stage Fusarium avenaceum (Jet.) Sacc. and Fusarium culmorum (W. G. Sm.) Sacc. The field trials were located at 440 and 630 m a.s.l. These elevations correspond to plain and mid-mountain climates, respectively. The tetraploid varieties 'Lipo', 'Tetila', 'Citadel' and 'Bastion' showed a higher level of resistance to snow mould compared to the diploid varieties 'Ursus', 'Lemtal', 'Melino' and 'Pablo'. Tetraploid ryegrasses contaminated the soil with Gerlachia nivalis to a lesser extend than diploid ryegrasses. The influence of the date of cutting and of nitrogen fertilization in autumn on snow mould was also tested. Lowest values at both locations were observed when the last cutting occurred at the end of October. Severity was higher when the last cutting took place earlier (mid September, end of September, mid October). Since parts of stands of the last cutting were strongly damaged by the cold, last cutting should take place in the middle of October, although infection with snow mould will not be as much reduced as if the last cutting was done at the end of October. The plant rotting caused by Gerlachia nivalis was increased with 80 kg N/ha in autumn compared with 40 kg N/ha. [ABSTRACT FROM AUTHOR]

Italian ryegrass (Lolium perenne ssp. multiflorum (Lam) Husnot) is a troublesome weed species in wheat (Triticum aestivum) production in the United States, severely affecting grain yields. Spatial mapping of ryegrass infestation in wheat fields and early prediction of its impact on yield can assist management decision making. In this study, unmanned aerial systems (UAS)-based red, green and blue (RGB) imageries acquired at an early wheat growth stage in two different experimental sites were used for developing predictive models. Deep neural networks (DNNs) coupled with an extensive feature selection method were used to detect ryegrass in wheat and estimate ryegrass canopy coverage. Predictive models were developed by regressing early-season ryegrass canopy coverage (%) with end-of-season (at wheat maturity) biomass and seed yield of ryegrass, as well as biomass and grain yield reduction (%) of wheat. Italian ryegrass was detected with high accuracy (precision = 95.44 ± 4.27%, recall = 95.48 ± 5.05%, F-score = 95.56 ± 4.11%) using the best model which included four features: hue, saturation, excess green index, and visible atmospheric resistant index. End-of-season ryegrass biomass was predicted with high accuracy (R2 = 0.87), whereas the other variables had moderate to high accuracy levels (R2 values of 0.74 for ryegrass seed yield, 0.73 for wheat biomass reduction, and 0.69 for wheat grain yield reduction). The methodology demonstrated in the current study shows great potential for mapping and quantifying ryegrass infestation and predicting its competitive response in wheat, allowing for timely management decisions. [ABSTRACT FROM AUTHOR]

Features the U.S. registration of the cultivar 'Shiwasuaoba' annual ryegrass, Lolium multiflorum. Research leading to the development of Shiwasuaoba; Developers of the cultivar; Breeding program; Resistance to crown crust; Possession of several B-chromosomes.

Offers information on the registration of the cultivar Secretariat Kentucky ryegrass with the agricultrual authorities in Washington. Developer of the plant variety; Plant structure and appearance; Average annual seed yield.

Reports the registration of perennial ryegrass named Citation III released by Pure Seed Testing Inc. Date released; Development of Citation III in cooperation with the Agricultural Experiment Station in New Jersey; Characteristics of the Citation III.

The article focuses on Wisconsin farmer Peter Pitts and his festulolium ryegrass. It cites how Pitts introduced his ryegrass variety to U.S. Dairy Forage Research Center Agricultural Research Service (ARS) geneticist Michael Casler. Pitts received a U.S. Department of Agriculture (USDA) small business grant to determine the superiority of his ryegrass variety with the assistance of Pure-Seed Testing Inc. of Hubbard, Oregon.

Discusses the abstract of the study 'The effect of early calf weaning followed by rye-grass (Lolium multiform) grazing on performance of fall-born cavles in Florida,' presented at the American Society of Animal Science's Southern Section conference on January 31-February 4, 2003, in Mobile, Alabama.

Reports on the registration of the cultivar Jumbo tetraploid annual ryegrass, with the U.S. Department of Agriculture. Origins of the cultivar; Development of the breed; Average grain yield.

Focuses on a report by Lyons and Schwartz, which suggests that rare plant species contribute to the resistance of ecological communities to invasion. Series of experiments in a California grassland ecosystem; Susceptibility to successful invasion by an exotic ryegrass.