Interseeding alfalfa (Medicago sativa L.) into bermudagrass [Cynodon dactylon (L.) Pers.] can be an effective way to improve forage quality and reduce the need for additional supplementation when fed to livestock. The objective of this research was to compare the nutritive value and forage mass of bermudagrass with and without interseeded alfalfa when harvested as baleage. On 19 Feb. 2016, 0.2‐ha plots were assigned in a randomized complete block design to either ‘Tifton 85’ (T85) or T85 interseeded with ‘Bulldog 805’ alfalfa (T85+Alf) in an established field of Tifton 85 bermudagrass at the University of Georgia Tifton Campus, Tifton, GA. The T85 received 84 kg N ha−1 four times throughout the growing season. Plots were harvested at early bloom stage every 28–35 d throughout the growing season, baled at 40–60% moisture, and individually wrapped. At each harvest, plots were evaluated for botanical composition and forage mass, and bales were sampled prior to wrapping for nutritive value analysis. The T85+Alf plots produced additional harvests each season, leading to greater herbage accumulation than T85 plots (P < .01). The T85+Alf treatment had greater crude protein and total digestible nutrients than T85 in each of the 3 yr, suggesting this mixture will need no or less supplementation to meet the nutritional requirements of a lactating beef cow. Therefore, interseeding alfalfa into a bermudagrass system improves forage mass and nutritive value.

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Potassium fertilization and harvest timing both influence the stand life and performance of alfalfa (Medicago sativa L.), but many producers do not apply sufficient K fertilizer as recommended by soil test recommendations. The objective of this trial was to determine the impact of reduced rates of K fertilization on cultivar Bulldog 805 alfalfa managed under different harvest regimes on forage yield, stand persistence, and nutritive value when grown in the southern Coastal Plains. Plots were harvested at bud, 10, 30, and 50% bloom growth stages. Potassium was applied three times across the season at total rates of 0, 67, 101, 134, and168 kg K 2 O ha −1 . Aboveground and belowground plant and soil responses were evaluated. Evaluated levels of K were not sufficient to elicit a positive response in aboveground variables, as all treatments exhibited K deficiency as confirmed by tissue analysis at the end of the study. Harvest timing affected many of the aboveground yield components, however no clear trends existed. As expected, material harvested at later growth stages tended to have higher fiber and lower digestibility than alfalfa harvested at less mature stages. Reduced rates of K fertilization helped maintain soil K levels above the final level in the untreated control. Harvesting alfalfa at later (50% bloom) growth stages decreased starch and nonstructural carbohydrate (NSC) content in the roots. To optimize both alfalfa yield and nutritive value, current University recommendations for alfalfa harvest timing and K fertilization should be maintained in the southern Coastal Plains. Abbreviations: ADF, acid detergent fiber; CP, crude protein; DM, dry matter; ESC, ethanol-soluble carbohydrate; IVTDM, in-vitro true dry matter digestibility; NDF, neutral detergent fiber; NFC, nonfibrous carbohydrates; NIRS, near infrared reflectance spectroscopy; NSC, nonstructural carbohydrates; TDN, total digestible nutrients.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Background Bermudagrass (Cynodon spp.) is one of the most common perennial warm‐season forages grown in the Southeastern United States. The incorporation of alfalfa (Medicago sativa) into bermudagrass pastures could serve as an alternative source of nitrogen (N) while also improving the nutritive value of the forage base. Methods A 2‐year grazing evaluation arranged in a randomized complete block design was conducted from May to September 2018 (Year 1) and May–August 2019 (Year 2) in Tifton, GA, USA. The objective was to compare the production of alfalfa–bermudagrass mixed pastures (BGA) with bermudagrass monoculture pastures with (BGN) or without (BG) the application of synthetic nitrogen on forage production and stocker cattle performance. Results Differences were observed for average daily gain (p = 0.10), gain per hectare (p = 0.02) and stocking rate (p = 0.01), in that BGA was greatest compared to BGN and BG, which did not differ from each other. Furthermore, BGA had increased forage crude protein (p = 0.01) and total digestible nutrients (p = 0.01) compared to BGN and BG. Finally, BGA provided the greatest economic return per hectare compared to BG or BGN. Conclusions These data illustrate improved animal performance and forage nutritive value using alfalfa–bermudagrass systems and offer a viable option for producers seeking alternatives to synthetic N sources for bermudagrass pastures in the Southeastern United States.

Core Ideas Temperature significantly affects the time and rate of clover (Trifolium spp.) germination. Germination and vigor were evaluated from −1.0 to 48.0°C at approximately 1.0°C increments. Tested cultivars maintained 80% + germination from 4.9 to 28.2°C, on average. Temperature range for germination was much wider than reported in previous literature. Data will be useful in updating planting recommendations for producers in the US Southeast. There are many reports of failed clover (Trifolium spp.) establishments each year. Temperature is one of the primary factors affecting germination and significantly affects the time and rate of clover seed germination. The objectives were to determine (i) the temperature and time required to reach maximum germination and (ii) range in which germination will occur for six coated clover cultivars adapted to the US Southeast. Seed germination and vigor were evaluated in Petri‐dishes incubated over thermal gradients ranging from −1.0 to 48.0°C at approximately 1.0°C increments where germination was counted every 24 h for 7 consecutive days. Base temperatures were calculated for each cultivar. Three parameter logistic growth models were used to find the minimum and maximum temperatures at which these cultivars could maintain 80% germination. Lorentzian distribution models were used to establish the temperature and time to maximum germination. These cultivars maintained at least 80% germination from 4.9 to 28.2°C on average, although some germination was observed outside these extremes. The range at which these clovers could germinate was much wider than previously reported. Excluding ‘Barduro’, maximum germination occurred at 34.2 to 52.8 h after planting at optimum temperatures (10.9–17.2°C). Barduro germinated so rapidly in the warmer temperature range that the full data set could not be used, as it did not conform to the same regression. Future trials will begin measuring germination at 12 h to better capture early trends in germination. These data will be useful in updating planting recommendations for producers in the US Southeast.