Silage Yield Research Articles

Agroenvironmental Performances of Biochar Application in the Mineral and Organic Fertilization Strategies of a Maize–Ryegrass Forage System

Biochar, included as a soil amendment by EU Regulation 2019/1009, has been shown to increase soil organic C stock and nutrient retention. We investigated the effect of biochar incorporation alone (B) and in association with mineral (BMin), digestate (BDig) and slurry (BSlu) fertilization, compared to the respective controls without biochar (C, Min, Dig and Slu), in a silage maize–Italian ryegrass rotation, on yield, soil fertility parameters and nitrous oxide (N2O) emissions. Two types of biochar in three doses (0.2, 0.45, 0.9%) were tested in two cropping seasons. Biochar did not significantly affect maize yield; however, BDig tended to increase silage yield and the ear component compared to Dig, while BMin tended to reduce maize N uptake compared to Min. Biochar incorporation significantly increased soil organic C (+31%) and cation exchange capacity (CEC) (+13%) in all the fertilization treatments; BMin and BDig also showed an increase compared to biochar alone (B). Emission of N2O was mainly driven by fertilization, digestate exhibiting the highest emissions. Biochar addition decreased the cumulative N2O emissions consistently in all the fertilization treatments, though not significantly. The association of biochar with organic fertilizers, in particular digestate, appears promising in increasing the fertilizer efficiency and reducing N2O emissions.

Factors determining yield and nutritive value of maize for silage under tropical conditions

AbstractOur objective was to assess maize fields in two growing seasons to determine the factors that affect the yield and nutritive value of maize silage produced in Brazil. Seventy‐four commercial maize fields, 49 in the first growing season (FGS) and 25 in the second (SGS), were sampled over two crop years. In each field, 12 linear meters of plants were cut by hand at 25 cm above ground. Characteristics of the field, plants, and their components (stalk, leaves, husk, cob, and grains) were evaluated. Farmers were interviewed regarding the crop management practices applied. Chopped maize forage was dried to assess its chemical composition, in vitro dry matter digestibility, and in vitro fibre digestibility. Descriptive statistics was carried out for agronomic and nutritional variables. To determine the factors that affected yield and nutritive value in maize fields, artificial neural networks were used. The dry matter yield (DMY), NDF concentration, starch concentration, NDF digestibility, and DM digestibility were chosen as response variables. Then, the top 10 main parameters were used to explain the results. Overall, the association between grain and stover yield maximized DMY. Plant population (plants/ha) and plant maturity were also important to explain yield. Grain depth and number of grains per row were the two most important parameters linked to genetic traits. Plant maturity was decisive in altering the nutritive value of forage maize. Maize grown in the FGS had both greater yield and nutritive value than maize in the SGS.

CO2 emission from soil in silage maize irrigated with wastewater under deficit irrigation in direct sowing practice

It is necessary to understand and measure the impact of tillage and irrigation practices on CO2 emissions from the soil with an environmental sensitivity, while wastewater irrigation increases crop biomass yield. The main objective of the present study was to investigate the changes and reasons in CO2 emissions from soil conventional and conservative tillage under different levels of wastewater irrigation. The CO2 emission from tillage-sowing to harvest over the regular measurements with a EGM-5 infrared gas analyzer device was investigated with three replicates in three deficit irrigation levels (0%, 33%, and 67%) of domestic recycled wastewater in conventional tillage and direct sowing practices. Binary relationships of CO2 emissions with H2O emission, air temperature, and the soil temperature and moisture measured at three different depths (5 cm, 10 cm, 20 cm) were also investigated and strong (p < 0.01) positive linear correlations were determined. Wastewater irrigation and conventional tillage significantly increased CO2 emissions compared to freshwater irrigation and direct sowing practice, while deficit irrigation practice decreased it. The direct sowing reduced seasonal CO2 emissions 25.1% and 26.1% for per unit area (1 ha) of silage maize and per unit of fresh silage yield (1 kg), respectively, compared to conventional tillage. The lowest CO2 emission per unit area and yield was determined in full irrigation treatment with freshwater in direct-sowing, while, in wastewater applications, it was determined in irrigation levels 33% per unit area and 67% per unit yield, under direct sowing. Thirty-three percent and 67% treatments in direct sowing resulted in less seasonal CO2 emissions as 38.7% per unit area and 13.8% per unit fresh silage yield, respectively compared to full irrigation treatment with freshwater in conventional tillage. Mean CO2 emissions in these treatments were found lower 17.9% per unit area and higher 17.8% per unit fresh silage yield compared to the full irrigation treatment with freshwater in direct-sowing. It was concluded that CO2 emissions per unit yield could be decreased with 33% water saving under wastewater irrigation conditions, and could be achieved environmental additional benefits from more decreasing CO2 emission by direct sowing also.

Ivyleaf morningglory (Ipomoea hederacea Jacq.) competition is not intensified by drought in silage corn in central New York State, USA

Ivyleaf morningglory (IMG, Ipomoea hederacea Jacq.) is a summer annual vine that is native to the Americas and invasive globally. This species decreases field crop yields through competition and interference with harvesting. Here, we explore the potential of IMG to compete with silage corn ( Zea mays L.) in New York State, USA. In a 2-year field study, we measured silage yield at five IMG planting densities (0–8 plants m−2) under no-drought conditions and a drought treatment established with rainout shelters. Volumetric water content was 26%–28% lower in the drought treatment than the no-drought treatment. Drought reduced fresh corn silage yield ( P = 0.003). Fresh silage yield was 21 600 ± 700 kg ha−1 in the no-drought treatment in 2016, 19 100 ± 900 kg ha−1 in the drought treatment in 2016, 30 500 ± 900 kg ha−1 in the no-drought treatment in 2017, and 28 200 ± 700 kg ha−1 in the drought treatment in 2017. Silage yield was not strongly responsive to IMG density, regardless of drought. These data suggest that the risk of corn silage yield losses due to IMG is relatively low in New York State and unlikely to be affected by drought. The risk posed by IMG may differ in other cropping systems or regions and under climate change.

Yield and nutritional value of sorghum genotype silages using Azospirillum brasilense in the northern region of the state of Minas Gerais

Sorghum is a crop of great interest in animal feed in semiarid regions. The environment and nitrogen fertilization can influence its productive potential and nutritional quality. This study aimed to evaluate sorghum biomass genotypes associated or not with Azospirillum brasilense managed at different sowing sites on the yield and nutritional value of silage. We evaluated 3 sorghum genotypes combined with 3 fertilization strategies using urea, Azospirillum brasilense and the urea/A brasilense combination in two planting sites (Janaúba, MG, and Montes Claros, MG). A randomized block design was carried out in a 3 x 3 x 2 factorial arrangement of 3 genotypes, 3 fertilization strategies and 2 sowing sites. Azospirillum brasilense foliar spraying was carried out using a costal (Backpack) atomizer and for silage production, PVC silos with weight and length of 50 cm and 10 cm in diameter were used. There was no triple interaction between the studied variables. There were differences between genotypes and between sites for agronomic traits. Statistical differences were detected between genotypes and sites for chemical composition, and sorghum forage on digestibility evaluations. The region of Montes Claros has greater forage production and the region of Janaúba has better quality of silage. Biomass sorghum genotypes have higher forage production and the Volumax genotype has better silage quality.

High-digestible silages allow low concentrate supply without affecting milk production or methane emissions

In this study, we tested a response function comprising responses in milk to changes in organic matter digestibility of silages and concentrate supply. We studied the effect of changes in silage digestibility and concentrate supply on milk yield, feed intake, body weight, and methane production using 60 Norwegian Red cows. The experiment was a complete randomized block design comprising 3 periods. The pre-experimental period lasted 20 d and all the cows were fed a common silage for ad libitum intake and concentrate according to yield. Next, response period 1 lasted 17 d and the cows were divided into 2 treatments, where a low-digestible silage (LDS) was fed to half of the cows, and the other half were fed a high-digestible silage (HDS). Both groups were fed silage for ad libitum silage intake. Concentrate was optimized according to the yield and type of silage offered. In this period, the effect of silage was evaluated using a mixed model, including the results from pre-experimental period, with parity as a covariate and animal as a random effect. In response period 2, which lasted 20 d, the concentrate level was evaluated by dividing the silage digestibility treatments further into 3 subgroups. Concentrate was increased by 2 kg of dry matter (DM) per day, decreased by 2 kg of DM/d, or remained unchanged. In response period 1, silage treatments were optimized to obtain similar yields and resulted in a lower concentrate offer to HDS treatment. However, the HDS treatment showed a 3.0 kg of DM/d higher total feed intake due to a higher than expected silage intake. This resulted in 3.5 kg higher energy-corrected milk (ECM). Methane emissions were similar between silage treatments, but HDS showed lower methane per kilogram of DM due to its higher intake. The effect of concentrate supply level and interaction with silage digestibility was evaluated using mixed models, including the results for response period 1, with parity as a covariate and animal as a random effect. The reduction in concentrate offer by 2 kg/d in response period 2 was compensated for by increased 1.3 kg of DM/d of silage intake for HDS, resulting in similar intake (22.1 kg of DM/d and 21.7 kg of DM/d without and with concentrate reduction, respectively) and ECM yields (29.4 and 29 kg of ECM without and with concentrate reduction, respectively). However, concentrate offer reduction could not be compensated for by increased silage intake for LDS and resulted in lower milk yields (27.5 kg of ECM). Increased concentrate showed a higher marginal ECM response (kg of ECM per kg of additional concentrate intake) for LDS (1.8 vs. 3.3 kg of ECM for HDS and LDS, respectively). Thus, the drop in milk yields could be compensated for by increased concentrate offers if LDS are fed. Total methane production increased with increased concentrate intake, regardless of silage digestibility. Methane emissions per unit of milk were affected by total DM intake rather than by changes in silage digestibility and concentrate level. The results of this study are based on short-term periods and could show differences if study periods were longer; the results should be interpreted accordingly.

Positive associations of soil organic matter and crop yields across a regional network of working farms

AbstractThe amount of soil organic matter (SOM) is considered a key indicator of soil properties associated with higher fertility. Despite the ubiquity of assumptions surrounding SOM's contributions to soil functioning, we lack quantitative relationships between SOM and yield outcomes on working farms. We quantified the relationship between SOM and yields of corn (Zea mays L.) and silage for a dataset of 170 fields arrayed across 49 farms in a network of growers based in Wisconsin and Minnesota, USA. As SOM concentrations increase so do yields, though gains start to level off around 4% SOM. When examining the relationship between yield and soil health indicators representative of biologically active C pools, we found that mineralizable C has a stronger relationship with yield than permanganate oxidizable C. Mineral fertilizer, manure, and SOM had relationships of similar magnitude with yield, highlighting that SOM in combination with exogenous inputs likely plays an important role in driving agricultural productivity in this region. An interaction between SOM and crop rotation indicated that the impact of SOM on crop yields varied depending on rotation (continuous corn vs. corn in rotation). That is, continuous corn had lower yields than corn in rotation despite higher SOM concentrations. Our findings provide insight into the relationship between indicators of soil health, farm management, and crop yields for a set of working farms and lend support to the goals of soil health initiatives that rest on building SOM in agricultural soils to improve agricultural outcomes.

Influence of Varieties and Spacings on Growth, Biomass Yield and Nutritional Value of Corn Silage in Paddy Field

Abstract The objectives of the experiment were to determine plant spacing and variety to produce the suitable growth, yield components, biomass yield of field corn and nutritional value of corn silage in paddy field condition. The field experiment was conducted at the Lopburi Research Station, Khok Charoen district, Lopburi province, Thailand in 2018-2019 and was arranged in a split plot design in randomized complete block design (RCBD) with 4 replications. The main plot contained 3 plant spacings viz. 75×15, 75×20 and 75×25 cm and sub plot consisted of 5 field corn varieties (CP888, NS3, S7328, SW4452 and SW5). The results showed that wide spacing tended to produce higher ears per plant than narrow spacing. CP888 was the highest ears per plant variety. NS3 was the highest leaf/stem ratio variety. SW5 showed high leaf, stem and fresh biomass yield and it also produce ear yield closing to a high ear yield variety at 75×25 cm spacing. Moreover, SW5 also had high crude protein (CP) content, while plant spacing did not significantly affect acid detergent fiber (ADF), acid detergent lignin (ADL), ash, and lactic acid of corn silage. The widest spacing (75×25 cm) showed lower NDF than the narrowest spacing (75×15 cm). It was evident that SW5 and 75×25 cm spacing may be considered optimum for biomass yields without negatively affecting the corn silage quality. Keywords: Nutritional value, Paddy field, Plant spacing, Silage corn, Variety

Evaluating optimum seeding distances from subsurface banding poultry litter in crop rotations

AbstractPoultry litter is a nutrient‐dense fertilizer, but surface applications lead to nutrient losses to air, soil, and water. Objectives were to evaluate optimum subsurface‐applied poultry litter bands from crop seeding distance in a corn (Zea Mays L.)–soybean [Glycine max (L.) Merr.] rotation. Soil amendment treatments included planting 13, 25, and 38 cm from subsurface‐banded poultry litter, surface‐applied poultry litter, inorganic nitrogen (N), and 0 kg N ha−1 (control) in Year 1, followed by soybean in Year 2 (no new soil amendment applications). Across subsurface treatments, corn grain and silage yields were 45 and 30% greater compared with surface applications, respectively, with inorganic N not differing from 25‐ and 38‐cm bands during grain harvest. In Year 2, subsurface‐banded soybean grain yields were 26% greater than with inorganic N. Consequently, subsurface banding poultry litter may be an ecologically and agronomicallyviable replacement for surface litter applications in corn silage and grain systems and inorganic N in corn–soybean rotations.

Effects of Limited Irrigation and Nitrogen Rate on the Herbage Yield, Water Productivity, and Nutritive Value of Sorghum Silage

ABSTRACT To evaluate the herbage yield and silage quality of sorghum as affected by nitrogen and irrigation levels, a 2-yr experiment (2017–2018) was conducted in a semi-arid region of Iran. Three irrigation levels (supply 100, 75, and 50% of soil moisture deficit as I100, I75, I50) and three nitrogen levels (150, 300, and 450 kg urea ha−1 as N150, N300, N450) were evaluated. Increasing nitrogen levels increased green herbage yield (GHY), irrigation water use efficiency (IWUE), lactic acid (LA), propionic acid (PA), digestible organic matter (DOM), crude protein (CP), and metabolizable energy (ME) but reduced the pH, dry matter content (DMC), neutral detergent fiber (NDF), and acid detergent fiber (ADF) of silage. The I100 compared to I50 treatment, resulted in higher GHY (69%), ADF (4%), NDF (2%), DMC (5%), ash (4%), and LA (13%) but reduced the IWUE (14%), CP (15%), DOM (3%), GP (4%), and ME (3%). Overall, the I75× N450 can be considered as the suitable treatment for sorghum silage production in semi-arid regions by saving 24% of irrigation water and producing high GHY (117.52 Mg ha−1) with the maximum IWUE (23.64 kg m−3) and high content of CP (88.5 g kg−1) and PA (0.34 g kg−1). In conclusion, the I75× N450 is introduced as the superior treatment; however, in conditions of severe limitation of water resources, it is recommended to irrigate silage sorghum with the supply of 50% soil moisture deficit with the application of 150 kg urea ha−1 (I50× N150).

Optimizing Yield and Quality of Silage and Hay for Pea–Barley Mixtures Ratio under Irrigated Arid Environments

The changing climate, water scarcity, reduction in the land area under forage crops, expanding ruminant population, burgeoning demands for milk and meat production and food security concerns all insist on a necessary increase in forage production and quality. Cereal–legume mixed intercropping offers a biologically superior option to boost herbage yield and quality of preserved fodder (hay and silage), provided that rationalization of the component crop’s proportional ratio is performed. Therefore, the current study was conducted to determine the forage yield and quality of barley (Hordeum vulgare L.) and pea (Pisum sativum L.) mixtures at the ratios 100:0, 75:25, 50:50, 25:75 and 0:100. The experiment was laid out in the regular arrangement of a randomized complete block design with three replicates. The results exhibited that forage quality was significantly affected by the mixture ratio. There was a significant improvement in protein, fiber rate and digestibility from the mixture. The ratios of barley and pea with 50:50 and 25:75 produced the maximum productivity and the best quality of forage. Regarding forage preservation, silage recorded higher contents of crude protein, ash and lower fiber contents than hay. Among seed mixtures, 0:100 ratio of barley–pea yielded the highest quality of silage with the maximum crude protein, ash and digestibility with lowest fiber contents.

Predicted milk production per hectare based on yield and chemical composition of native and hybrid maize silage varieties on temperate and tropical regions

The objective of the present study was to characterize maize silage according to chemical composition, maize silage yield, as well as their predicted milk production. A search was made on studies related to maize silage yield, density, chemical composition (DM, CP, NDF, starch), and dry matter digestibility (DMD). In this study, 41 maize varieties from temperate regions and 101 maize varieties from tropical origin were analyzed. The net energy of lactation (NEL Mcal/kg DM), kilograms of milk per t of silage (kg of milk/t DM), and kilograms of milk per hectare of silage (kg of milk/ha) were determined. A cluster (CL) analysis was performed, and six CL of maize silage were obtained. The CL1 included digestibility for dry matter, crude protein, neutral detergent fiber, NEL, and kg of milk/t DM. CL2 was characterized by maize silage with the highest number of plants per hectare and NDF. CL3 included the highest ash content. CL4 consisted of intermediate values for all variables. CL5 included the highest forage yield (t DM/ha) and kg of milk/ha whereas CL6 included the highest kg of milk/t. Overall, CL1 resulted in the highest DMD and NEL, producing more milk per t DM. Results suggested that the ideal option is maize silage with a higher forage yield and more than 35 % DM (CL5) since this produces more kg of milk per hectare.

Assessment and Prediction of Maize Production Considering Climate Change by Extreme Learning Machine in Czechia

Machine learning algorithms have been applied in the agriculture field to forecast crop productivity. Previous studies mainly focused on the whole crop growth period while different time windows on yield prediction were still unknown. The entire growth period was separated into each month to assess their corresponding predictive ability by taking maize production (silage and grain) in Czechia. We present a thorough assessment of county-level maize yield prediction in Czechia using a machine learning algorithm (extreme learning machine (ELM)) and an extensive set of weather data and maize yields from 2002 to 2018. Results show that sunshine in June and water deficit in July were vastly influential factors for silage maize yield. The two primary climate parameters for grain maize yield are minimum temperature in September and water deficit in May. The average absolute relative deviation (AARD), root mean square error (RMSE), and coefficient (R2) of the proposed models are 6.565–32.148%, 1.006–1.071%, 0.641–0.716, respectively. Based on the results, silage yield will decrease by 1.367 t/ha (3.826% loss), and grain yield will increase by 0.337 t/ha (5.394% increase) when the max temperature in May increases by 2 °C. In conclusion, ELM models show a great potential application for predicting maize yield.

Establishment and First Year Yield of Interseeded Alfalfa as Influenced by Corn Plant Density and Treatment with Prohexadione, Fungicide and Insecticide

Interseeding alfalfa (Medicago sativa L.) into a silage corn (Zea mays L.) companion crop can increase the yield and profitability of forage production and reduce the risk of nutrient and soil loss from cropland, but unreliable establishment of alfalfa hampers the adoption of this practice on dairy farms. This study evaluated plant survival, foliar health, and dry matter yields of two alfalfa varieties when established in corn sown at populations ranging from about 47,500 to 100,000 plants per ha−1 and when treated with prohexadione (PHD), PHD followed by fungicide and insecticide (PHD-FI), or not treated with agrichemicals. The plant density of alfalfa during establishment was adversely impacted by above average precipitation and high corn populations, but substantially improved by PHD-FI treatment, which limited alfalfa etiolation, disease, and defoliation. First-cut dry-matter yields of interseeded alfalfa after corn were maximized at a stand density of approximately 200 plants m−2 or 850 stems m−2 and total first year yield exceeded conventionally spring-seeded alfalfa by 59 to 75%. Overall, our results indicated that PHD-FI treatment promoted good establishment and subsequent forage production of interseeded alfalfa. Applications of PHD-FI must, however, be fine-tuned, and additional management practices must be developed to ensure both good yields of corn silage and reliable establishment of interseeded alfalfa, especially during wet growing conditions.

Cover crop water use and corn silage production in -semi-arid irrigated conditions

Cover crops can increase crop water productivity (CWP) and succeeding crop yield. However, cover crops adoption in the Southern High Plains of USA is slow due to limited water available for crop production. This study evaluated the effects of winter cover crops on soil water dynamics, corn silage yield and nutritive values, and corn silage CWP in a semi-arid irrigated condition. Three winter cover crop mixtures: grasses + brassicas + legumes (GBL), grasses + brassicas (GB), grasses + legumes (GL), and control or no cover crop (NCC) were evaluated for soil water storage, cover crop biomass, corn silage yield, nutritive values, and crop evapotranspiration (ET), and the cover crop-corn silage system water productivity (SWP) under a no-till irrigated corn silage production system. All cover crop treatments reduced soil water storage before their termination in both years. However, water storage was higher for all cover crop treatments than for NCC during corn growth. Average CWP for corn was improved by 14–29% with cover crop mixtures over the NCC. Corn silage yield among cover crop treatments was 9–26% higher than NCC. Nutritive value components of cover crops such as non-fat carbohydrates, relative forage quality, and Ca and Mg were higher in the GBL and GL mixtures than the GB in one of the two years. This study demonstrated increased corn silage yield and water productivity with cover cropping. Cover crops mixtures with legumes could offer a high-quality alternative forage for crop-cattle integrated systems, including dairy producers in the Southern High Plains region.

Modeled performance of forage mixtures and annual crops grown in eastern Canada under climate change

AbstractTimothy (Phleum pratense L.) is expected to be more affected by climate change than other forage grasses. Therefore, alternatives to timothy, such as tall fescue [Schedonorus arundinaceus (Shreb.) Dumort.], meadow fescue [S. pratensis (Huds.) P. Beauv.], or meadow bromegrass (Bromus biebersteinii Roem. &amp; Schult.) should be explored. Our objective was to simulate and compare the yield and nutritive value of four alfalfa (Medicago sativa L.)–grass mixtures and annual crops grown on two virtual dairy farms representative of eastern Canada under future climate conditions. The Integrated Farm System Model (IFSM) was used for these projections under the reference (1971–2000), near future (2020–2049), and distant future (2050–2079) climates for two climatically contrasting agricultural areas in eastern Canada (eastern Quebec; southwestern Quebec). In both future periods, annual forage dry matter (DM) yields of the four alfalfa–grass mixtures are projected to increase because of additional harvests, with greater DM yield increases projected in the colder area than in the warmer area. In both areas, the highest yield increase is projected for alfalfa–tall fescue mixture and the lowest for alfalfa–timothy mixture. The nutritive value of all mixtures should increase due to a greater proportion of alfalfa. In both areas, yields of silage and grain corn (Zea mays L.), and soybean [Glycine max (L.) Merr.] are projected to increase, but not those of wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.). Tall fescue, meadow bromegrass, and meadow fescue are adequate alternatives to timothy grown in association with alfalfa under future climate conditions.

Silage corn yield is reduced by burcucumber competition and drought in New York State

AbstractDrought stress and weed competition are two of the most important threats to corn production in the northeastern United States. Both pressures have the potential to worsen under climate change. In a 2-yr field study in Ithaca, NY, we tested the effects of drought and burcucumber, an increasingly problematic annual vine, on silage corn. Burcucumber seedlings were transplanted into corn rows at densities of 0, 0.5, 2, and 3 plants m−2 and a drought treatment was later imposed with rainout shelters constructed from steel frames and high-clarity plastic. Available soil moisture was lower in drought plots (47% ± 1% in 2018 and 52% ± 2% in 2019) than no-drought plots (69% ± 1% in 2018 and 68% ± 1% in 2019). Burcucumber planting density (P = 0.008) reduced fresh silage yield. Drought also reduced fresh silage yield (P &lt; 0.001) with a drought-by-year interaction (P = 0.007): drought reduced fresh weight by 29% in 2018 (48,000 ± 2,000 kg ha−1 to 34,000 ± 3,000 kg ha−1) and by 9% in 2019 (38,000 ± 3,000 kg ha−1 to 34,000 ± 3,000 kg ha−1). Burcucumber planting density and drought did not interact. Overall, our findings indicate that drought and competition from burcucumber may have additive effects on silage corn in New York State. Regardless of water availability, active weed management is required to prevent yield losses due to burcucumber. Yield losses may be similar or greater in grain corn and might increase under climate change.

Rotational no‐till and tillage‐based organic corn produce management tradeoffs in the Northeast

AbstractReducing the intensity and frequency of tillage in organic grain production systems is likely to produce several agronomic, economic, and environmental tradeoffs. We evaluated four organic corn (Zea mays L.) sequences in a 3‐yr, full‐entry organic cropping systems experiment. Two sequences included a hairy vetch (Vicia villosa Roth)/triticale (Triticale hexaploide Lart.) mixture sown after spelt harvest that differed in tillage practices (no‐till [NT], conventional) before corn and corn harvest management (silage, grain). Two sequences included a red clover (Trifolium pretense L.)/timothy (Phleum pretense L.) mixture frost‐seeded into spelt in late winter followed by conventional tillage preceding corn and either silage or grain harvest. Our results showed that late‐season weed biomass did not differ across alternative sequences, although both tillage and NT corn production resulted in high in‐row weed pressure in different years. Cover crop management prior to tillage‐based corn production did not affect grain yields, but NT silage production resulted in lower yields compared with the tilled sequence. Corn silage yields were positively correlated with corn populations in both tilled and NT systems. The NT sequence lowered tillage frequency and intensity by 39 and 52%, respectively, compared with tillage‐based corn production as measured using established metrics, including the soil disturbance rating, but did not significantly influence labile carbon pools. Sequences using underseeded red clover resulted in higher net returns compared with hairy vetch sequences due to additional income from fall forage harvests.

SILAGE YIELD AND PROTEIN CONTENT OF FORAGE LEGUMES INTERCROPPING WITH CEREALS IN TWO SPATIAL ARRANGEMENTS

Intercropping of most annual legumes with winter cereals is a very common practice for forage production in many countries. The aim of this study was to determine the effect of different spatial arrangements of intercropping cereals with forage legumes on silage yield and protein content. The completely randomized design was applied with three replications. Particularly, common vetch and forage pea were used as forage legumes, and barley, and triticale were used as cereals, which were grown individually as well as intercropped with each other in mixed rows in a sowing ratio 65:35 or in alternate rows. The plants were harvested when the legumes were at the end of the flowering period and were separated by hand to determine the weight of fresh matter for each species. Samples of 100 g of hay from each experimental plot were used to calculate the dry matter and to determine the total N and subsequently the total protein content using the Kjeldahl method. In most cases differences were found between the treatments concerning the dry matter and the protein content. Regarding the fresh weight the mixtures triticale+common vetch (alternate rows), barley + common vetch (alternate rows) and barley+ forage pea (alternate rows) showed the higher yield. The forage pea gave the higher yield among the nonocrops. Regarding the dry weight the mixtures barley+ forage pea (alternate rows) and triticale+ common vetch (alternate rows) showed the higher yield. Additionally, significant differences were recorded between the examined genotypes in grain yield. The barley intercropped with forage pea (mixed rows) gave the higher yield. Regarding the grain yield of legumes, common vetch intercropped with barley (alternate rows) and forage pea intercropped with barley (both cases) gave the higher yield. In all cases the forage yield (weight of dry matter) was higher in separated lines compared to mixed lines. However, concerning the grain yield the mixed rows were probably more productive.

Competition, stress and benefits: Trees and crops in the transition zone of a temperate short rotation alley cropping agroforestry system

AbstractTree strips on agricultural production sites offer many economic, ecological and social advantages. However, the introduction of trees creates a transition zone between tree strips and crop land. Here, trees and crop plants compete for resources such as space, nutrients, water and light, which causes stress in the low‐competitive system. On the other hand, facilitation such as additional nutrient input through tree leaf litter and fine roots are possible. This study aims to provide indications for competition and benefits that can arise for plants growing in the transition zone of a temperate short rotation alley cropping agroforestry system (SRACS). Various climatic and plant‐growth parameters were investigated between 2013 and 2019 at different positions of an SRACS with fast‐growing poplars in northern Germany. Reduced yield of wheat, oilseed rape and silage maize close to the tree strip was associated with greater soil water tension in 30 and 60 cm soil depth due to the presence of poplar roots, reduced solar radiation due to tree shading and leaf litter coverage. In contrast, poplars growing in the outer rows produced more biomass than those in the inner rows due to the additional availability of space, light and nutrients taken from the crop field. Trees in the transition zone seem to be competitive with arable crops, but without effect on the average long‐term yield of arable crops.