What's Cropping Up? Blog

Articles from the bi-monthly Cornell Field Crops newsletter

March 22, 2017
by Cornell Field Crops
Comments Off on Planting Date and N Availability Impact Fall N Uptake of Triticale

Planting Date and N Availability Impact Fall N Uptake of Triticale

Sarah E. Lyonsa, Quirine M. Ketteringsa, Greg Godwina, Jerome H. Cherneyb, Karl J. Czymmeka,c, and Tom Kilcera,d
a
Nutrient Management Spear Program, Department of Animal Science, Cornell University, Ithaca, NY, b Soil and Crop Sciences Section of the School of Integrative Plant Science, Cornell University, Ithaca, NY, c PRODAIRY, Department of Animal Science, Cornell University, Ithaca, NY, and d Advanced Agricultural Systems, LLC, Kinderhook, NY

Introduction
Triticale planted as a double or cover crop after corn silage harvest in the fall can provide many benefits to forage rotations in the Northeast, including reduced risk of soil erosion over the winter months, enhanced soil organic matter, improved rotation diversity, and, if grown as a double crop, increased total season yields. In addition, triticale has the potential to take up readily available nutrients either left over from the previous crop or from fall-applied manure, reducing the potential for nutrient loss. The benefit of fall nutrient uptake will depend on how early the winter cereals are planted in the fall. To evaluate the impact of planting date and nitrogen (N) availability on the growth and N uptake of triticale, four trials were conducted from 2012-2014.

Trial Set-Up
The four trials were planted with triticale (King’s Agri-Seeds Trical 815 variety) from late August to early October in eastern NY (Valatie) and central NY (Varna). Each trial had two planting dates and, to create a range in soil nitrate availability, 5 N rates were applied at planting in the fall (0, 30, 60, 90, and 120 lbs N/acre). Triticale was planted at 1-inch seeding depth and 7.5-inch row spacing (120 lbs/acre seeding rate). In late November prior to frost, we sampled the above ground biomass and analyzed the biomass for carbon and nitrogen. The “Apparent N Recovery (ANR)” was also calculated for each trial to see how efficient the triticale was at recovering fall-applied N. The ANR is calculated by subtracting the total amount of N in the biomass when no N was applied from the amount of N in the biomass when N was applied, and dividing that value by the actual amount of N applied: ANR (%) = (Triticale NN rate – Triticale N0 N)/N rate. A higher ANR means more of the N that was applied was taken up by the triticale.

Results
Triticale planted before September 20 had more biomass than plots planted after September 20. For the triticale planted after the 20th, there was no increase in biomass when N was added. However, when triticale was planted earlier, N addition resulted in increased growth (Figure 1a). Across all N rates, biomass ranged from 0.6 to 1.1 tons DM/acre and averaged 0.9 tons DM/acre when planted before September 20, and 0.2 to 0.3 tons DM/acre with an average of 0.2 tons DM/acre when planted after September 20. These results are consistent with earlier studies in New York (see Ort et al., 2013), where triticale planted prior to September 20 yielded, on average, 0.7 tons DM/acre above-ground biomass in the fall, versus 0.2 tons DM/acre with later plantings.

In all four trials, biomass and N uptake were linearly related, meaning that as biomass increased, so did N uptake (Figure 1B). Thus, as N addition for later plantings did not increase yield, it also did not increase N uptake. Across all N rates, N uptake ranged from 36 to 78 lbs N/acre and averaged 62 lbs N/acre for the triticale planted before September 20, and ranged from 16 to 20 lbs N/acre with an average of 19 lbs N/acre for triticale planted after September 20. For every ton of DM triticale biomass produced in the fall, approximately 70 lbs of N was taken up.

Figure 1: Above-ground fall biomass accumulation (A) and nitrogen uptake (B) of triticale at different planting dates and N rates averaged across four trials.

Figure 2: Apparent nitrogen recovery (ANR) of triticale at different planting dates and fall N fertilizer rates, averaged across four trials.

The apparent N recovery was greater for earlier plantings (Figure 2). This is related to increased biomass production for the earlier planting dates, which has a direct impact on N uptake capacity of the triticale. The ANR averaged 47% for triticale planted before September 20, and only 5% for triticale planted after September 20.

Conclusions and Implications
Winter cereals, like triticale, grown as double or cover crops can take up residual N as well as additional N applied at or close to planting but the amount of N taken up depends on planting date. Triticale in this study was able to accumulate 0.9 tons DM/acre and take up 62 lbs N/acre on average when planted before September 20, but only 0.2 tons DM/acre biomass and 19 lbs/acre of N on average when it was planted after September 20. Additional N did not influence biomass or N uptake if triticale was planted late, but when planted early biomass did increase with greater N availability showing the benefits of early seeding for utilizing end-of-season N or newly applied N from manure. Planting winter cereals like triticale can sequester N that could otherwise be lost as well as provide dairy farmers with an additional opportunity to apply manure while reducing the risk of N loss. More research is needed to determine more precise planting windows for optimal N utilization by winter cereals in the Northeast, as well as determining an upper limit to the amount of manure that can be applied in the fall if a winter cover or double crop is planted.

Reference
Ort, S.B., Q.M. Ketterings, K.J. Czymmek, G.S. Godwin, S.N. Swink, and S.K. Gami. 2013. Carbon and nitrogen uptake of cereal cover crops following corn silage. What’s Cropping Up? 23: 5-6. Available at: https://scs.cals.cornell.edu/extension-outreach/whats-cropping-up.

Acknowledgements
This work was supported by Federal Formula Funds, and grants from the Northern New York Agricultural Development Program (NNYADP), New York Farm Viability Institute (NYFVI), and Northeast Sustainable Agriculture Research and Education (NESARE). For questions about these results, contact Quirine M. Ketterings at 607-255-3061 or qmk2@cornell.edu, and/or visit the Cornell Nutrient Management Spear Program website at: http://nmsp.cals.cornell.edu/

 

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January 25, 2017
by Cornell Field Crops
Comments Off on Anatomy of a Rare Drought: Insights from New York Field Crop Farmers

Anatomy of a Rare Drought: Insights from New York Field Crop Farmers

Shannan Sweet and David Wolfe
School of Integrative Plant Science, Cornell University

Key Findings

  • The record-breaking 2016 drought affected farmers across New York State (NYS) with more severe effects in Western and Central NY than Eastern NY.
  • Crop loss estimates from a late summer survey of ~200 field crop farmers suggest that more than 70% of field crop and pasture acreage had losses greater than 30%, with some reporting nearly total crop failure.
  • Common suggestions from farmers on help they could use in dealing with future drought included better long-range weather forecasts, financial assistance to expand irrigation capacity, and more information on drought resistant crops.

Background
An unusually low winter snow pack, followed by lower than average rainfall and higher than average temperatures during the 2016 growing season (NRCC) led to continuously worsening drought conditions throughout New York State, and record-breaking low stream flows in Western and Central NY by late July and August (Drought Monitor). New York (NY) farmers have asked if they should expect more dry summers like the one we had in 2016 in the future with climate change. The answer to that is we don’t entirely know. Climate scientists are fairly certain that the number of frost-free days will continue to increase and summers will be getting warmer, which will increase crop water demand (Horton et al. 2011; Walsh et al. 2014). Climate models are less reliable for predicting rainfall and snow, but most projections suggest that total annual precipitation will remain relatively stable in New York, with small decreases in summer months and possible increases in winter. Also, the recent trend of the rainfall we do get coming in heavy rainfall events (e.g. more than 2 inches in 48 hours) is likely to continue.This would suggest both flooding and drought will continue to challenge New York farmers, and it is possible that more severe short-term droughts in summer could increase in frequency. Given these projected impacts, we surveyed NY farmers throughout August and September (Drought Survey) so as to better understand how farmers were affected by the 2016 drought and if they are able to cope with drought risk. The survey was distributed online and in paper format with the help of Cornell Cooperative Extension and the Farm Bureau. Of the approximately 240 farmers that responded to the survey, 183 of those were field crop farmers from every county in Western NY, and several agricultural counties in Eastern NY (Fig. 1).

Fig. 1. Drought survey responses by county. New York State number of farms map (Source: 2012 USDA NASS, ESRI – 12-M249), where darker green colors indicate a greater number of farms. Red dots indicate counties where field crop farmers responded to the survey. The dotted line delineates two regions (WNY = Western NY and ENY = Eastern NY). Counties in WNY were those designated as “national disaster areas” due to the drought.

 

Drought Impact

Fig. 2. Percent of respondents that estimated field crop yield losses within certain percent ranges. Forages include hay, grasses, and alfalfa. Data is averaged across NY.

Across the state, farmer-estimated crop losses for forages, pasture, soybeans, field corn, and small grains were 41%, 42%, 33%, 31%, and 17%, respectively. Figure 2 illustrates that estimated losses of more than 30% were reported for many field crops, and some forage and soybean farms reported losses above 90%. When asked what most limited field crop farmers’ ability to maintain yields, 37% said limited water supply, 25% said inadequate irrigation equipment, and 16% said poor soil water holding capacity (data not shown). Of the 22% who reported that other factors most limited their ability to maintain yields, several mentioned: lack of time and labor, excessively hot temperatures and high solar radiation, and being completely unprepared for needing to irrigate. Additional comments from farmers related to the effect of the drought included statements about: extra costs associated with buying hay, and having to sell cattle due to an inability to keep them watered and fed. Several farmers indicated factors that helped them get through the drought, including: cover cropping, no-till farming, increased soil health, and improved grazing management. The drought impact was so severe in Western NY (WNY) that the USDA-Farm Service Agency (FSA) declared most counties in this region “natural disaster areas” in August of 2016, and eligible for some financial relief in the form of low-cost loans (FSA). The more severely drought stricken field crop farms in WNY reported higher crop loss compared to Eastern NY (ENY) (Table 1). A vast majority of field crop farmers in WNY estimated the overall economic impact to be “moderate’’ to “severe” and, though many farmers in ENY also felt a substantial economic blow, about half categorized the impacts as “minor” or a “nuisance” with almost no economic impact (Fig. 3).

Fig. 3. Field crop farmer’s rating of the economic impact of the drought.

 

 

Adaptive Capacity

Field crop farmers’ responses varied when asked what they might have done differently if they had known in advance how dry this summer would be (Fig. 4). Many (37%) selected the “other” category and included suggested changes related to increasing soil organic matter and water holding capacity (e.g. cover crops and no-till), changing hay cutting regimes and increasing rotational grazing, investing in other water resources, selling or slaughtering livestock, and many others. A few farmers said they would not have done anything different if the drought could have been anticipated.

Fig. 4. Production changes field crop famers would have made if the drought could have been anticipated.

Insights for extension educators, researchers and policy makers
When asked how organizations such as Cornell Cooperative Extension, university researchers or government and non-government agencies could help them cope with future drought risk, farmers expressed interest in knowing more about:

  • Drought resistant crop varieties
  • Irrigation development and planning
  • Improving soil quality and water retention, and water saving ideas
  • Pasture rotation, silvopasture, rotational grazing, and stockpiling forage
  • How to minimize the effect of drought
  • What pests and diseases are more (or less) prevalent during a drought
  • Dealing with mental stress related to drought and climate issues

In response to that same question, farmers said they wanted more:

  • Development of online tools and better long-range forecasting
  • On-farm courses and training, and educational materials about agriculture and drought
  • Financial assistance to cover drought losses
  • Inventory of vacant farmlands for potential use
  • Financial assistance for irrigation equipment and ponds, and for soil improvement and water management
  • Crop-specific crop insurance or discontinue crop insurance which encourages growing ill-suited crops
  • Rentable and leasable irrigation equipment, and cheaper county water for agricultural use
  • Cost sharing for: cover crops and no-till supplies, and for multi-purpose ponds

This project was funded by Cornell University’s Atkinson Center for a Sustainable Future and The Nature Conservancy. For more information contact Shannan Sweet: 126 Plant Science Bldg., Ithaca, NY 14853; 607 255 8641, sks289@cornell.edu.

References and Hyperlinks
Drought Monitor – http://droughtmonitor.unl.edu/
Drought Survey – https://dl.dropboxusercontent.com/u/27816/Survey_Drought_8-5-16%20(mail-in).pdf
FSA (Farm Service Agency) – http://www.fsa.usda.gov/news-room/emergency-designations/2016/ed_2016_0825_rel_0095
Horton R, Bader D, Tryhorn L et al. (2011). Ch. 1: Climate Risks. In: Responding to Climate Change in New York State: The ClimAID Integrated Assessment for Effective Climate Change Adaptation. New York Academy of Sciences. pp 217-254.
NRCC (Northeast Regional Climate Center) – http://www.nrcc.cornell.edu/regional/drought/drought.html
USDA (United States Department of Agriculture) – https://www.agcensus.usda.gov/Publications/2012/Online_Resources/Ag_Census_Web_Maps/
Walsh J, Wuebbles D, Hayhoe et al. (2014): Ch. 2: Our Changing Climate. In: Climate Change Impacts in the United States: The Third National Climate Assessment. U.S. Global Change Research Program, 19-67.

 

 

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December 7, 2016
by Cornell Field Crops
Comments Off on What’s Cropping Up? – Volume 26 No. 6 – November/December Edition

What’s Cropping Up? – Volume 26 No. 6 – November/December Edition

The full version of What’s Cropping Up? Volume 26 No. 6 is available as a downloadable PDF and on issuu.  Individual articles are available below:

December 5, 2016
by Cornell Field Crops
Comments Off on Perennial Grain Crop Production in New York State

Perennial Grain Crop Production in New York State

Sandra Wayman, Eugene Law, Valentine Debray, Chris Pelzer, and Matthew Ryan
Soil and Crop Sciences Section, School of Integrative Plant Science, Cornell University

What are perennial grain crops?
Grain crops constitute the majority of human caloric intake and have been bred for high yields and consistent production. Although these crops are incredibly productive and feed billions of people every year, intensive cultivation of grain crops can contribute to soil and water degradation because of annual operations that often include planting into tilled soil.

Figure 1. Kernza, a perennial grain, prior to grain harvest at the Cornell Musgrave Research Farm in Aurora, NY, on August 11, 2016.

Figure 1. Kernza, a perennial grain, prior to grain harvest at the Cornell Musgrave Research Farm in Aurora, NY, on August 11, 2016.

Perennial grain crops are one solution to some of the problems associated with annual grain crops. Perennial grain crops have lower annual production costs than annual grain crops because farmers do not need to purchase seed or use labor and fuel for planting each year. Because of year-round ground cover and deeper root systems than annual crops, perennial grains can also be produced more sustainably on sloped land that is prone to soil erosion.

Dr. Wes Jackson, founder of the Land Institute in Kansas, has been promoting perennial grains for the last 40 years. At first perennial grain crops were just an idea, but now they are becoming a reality and attracting the attention of farmers, bakers, brewers, and consumers. One particular perennial grain crop, intermediate wheatgrass (Thinopyrum intermedium) is especially advanced and well poised for adoption. However, grain yields of intermediate wheatgrass are substantially lower than from comparable annual grain crops, such as wheat.

Intermediate wheatgrass is a long-lived, rhizomatous perennial grass native to central Asia. In the early 1980’s, researchers at the Rodale Institute evaluated nearly 100 perennial grass species for potential domestication, and selected intermediate wheatgrass due to its favorable yield potential, nutritional profile, and suitable agronomic traits. Work with intermediate wheatgrass was later carried out at the NRCS Big Flats Plant Materials Center in Big Flats, New York. Now, Dr. Lee DeHaan at the Land Institute in Kansas is leading breeding efforts with this perennial grain crop, which is marketed as Kernza®.

Figure 2. De-hulled Kernza grain (left), harvested from plots in Aurora, NY and a can of the first commercially available product made from Kernza grain (right).

Figure 2. De-hulled Kernza grain (left), harvested from plots in Aurora, NY and a can of the first commercially available product made from Kernza grain (right).

The Cornell Sustainable Cropping Systems Lab has been working on perennial grains for the past two years. Here we summarize some of our recent projects related to perennial grains.

Multi-site forage experiment
In August of 2014, we initiated a long-term experiment (Figure 3) at the Cornell Musgrave Research Farm in Aurora, NY in collaboration with Dr. Steve Culman (a Cornell Soil and Crop Sciences alumnus, now Assistant Professor of Soil Fertility at The Ohio State University) and five other researchers across the US. The objectives of this experiment are to: 1) determine the effects of harvesting forage on Kernza grain yields and profitability, and 2) evaluate Kernza grain and forage yields over time across multiple environments.

Figure 3. Farmer advisors and Cornell University researchers evaluate a plot of Kernza at the Musgrave Research Farm, July 19, 2016.

Figure 3. Farmer advisors and Cornell University researchers evaluate a plot of Kernza at the Musgrave Research Farm, July 19, 2016.

We planted Kernza at 15 lb seed/acre at 7.5-inch row spacing using a grain drill. Although this experiment compared several treatments, here we focus on two. One treatment, ‘Grain’, was harvested for grain and then straw in the summer. The other treatment, ‘Forage & Grain’, included a spring forage harvest prior to stem elongation (Figure 4) in addition to the summer grain and straw harvest. We measured forage yield, grain yield, and plant height at grain harvest.

Figure 4. Kernza harvested for forage prior to stem elongation by cutting the early vegetative growth to a height of 4-inches on May 9 2016.

Figure 4. Kernza harvested for forage prior to stem elongation by cutting the early vegetative growth to a height of 4-inches on May 9 2016.

In 2015, grain yield was lower in the ‘Forage & Grain’ treatment compared to the ‘Grain’ treatment (Figure 5), showing that harvesting forage in the spring can reduce grain yields slightly. In 2016, there was no difference between these treatments. Straw production was greater in the ‘Grain’ treatment than in the ‘Forage & Grain’ treatment in both years (Figure 5). Spring forage yields in the ‘Forage & Grain’ treatment averaged 1,390 lb/ac (standard error ±340 lb/ac) across both years. Noteworthy is that the spring biomass had better forage quality than the straw at grain harvest (Table 1). Although it appears that Kernza can produce high quality forage, which might offset the relatively low grain yields and increase profitability, more research is needed to determine how harvesting forage in the spring prior to stem elongation affects crop performance.

 Figure 5. Kernza straw (above) and grain (below) yield for treatments ‘Grain’ and ‘Forage & Grain’ in 2015 and 2016. Error bars indicate standard error within each treatment within a year. Harvest occurred on September 11, 2015 and August 23, 2016. Kernza grain yields are based on a subsample of hulled grain that was hand threshed and a conversion factor was then used to estimate yield expressed as cleaned and de-hulled grain.


Figure 5. Kernza straw (above) and grain (below) yield for treatments ‘Grain’ and ‘Forage & Grain’ in 2015 and 2016. Error bars indicate standard error within each treatment within a year. Harvest occurred on September 11, 2015 and August 23, 2016. Kernza grain yields are based on a subsample of hulled grain that was hand threshed and a conversion factor was then used to estimate yield expressed as cleaned and de-hulled grain.

Table 1. Forage quality metrics for Kernza forage harvested in spring at elongation and in summer at grain maturity in 2015. Prime forage standards from “What is Forage Quality”, Ashley Pierce, Rensselaer County Cornell Cooperative Extension. Spring forage harvest dates were May 22, 2015 and May 9, 2016. Summer straw forage harvest dates were September 11, 2015 and August 31, 2016.

Perennial grains survey
Given that perennial grains are a novel development and farmers have not grown these crops before, we conducted an online survey with Dr. Christophe David from ISARA-Lyon in France, to assess farmers’ potential interest in perennial grains. A link to the survey was e-mailed to farmers in the US and France, and posted on pertinent farming websites. A total of 88 and 319 farmers, in the US and France respectively, responded to the survey between June 23 and July 25, 2016.

Farmers were asked about: 1) their previous knowledge of perennial grains, 2) their interest in growing them, and 3) factors motivating their interest. Fifty-eight percent of respondents said they were “interested” or “very interested” in growing perennial grains, and 39% said they “needed more information”. Seventy-three of farmers who had already heard about perennial grains before the survey said they were “interested” or “very interested”, whereas 47% of farmers who did not know about these crops said they were “interested” or “very interested”. The top three reasons selected by farmers for growing perennial grains were: “to increase or maintain farm profitability” (56%, n=188), “to reduce labor requirements” (44%, n=145), and “to improve soil health” (44%, n=145).”

New perennial grain field experiment
In September 2016, we started a 3-year field experiment at Cornell Musgrave Research Farm in addition to planting three on-farm strip trials with collaborating farmers. The goal of this work is to measure the effect of perennial grains on soil health and to work with farmers to develop management guidelines. The grain from our field experiments will be tested by local bakers, brewers, and distillers, which will help guide future research.

At the Cornell Musgrave Research Farm we are comparing perennial rye (Secale cereale x S. montanum) and Kernza side-by-side with an annual malting barley cv. ‘Endeavor’ and a hard red winter wheat cv. ‘Warthog’. These plots will have a split-plot treatment of interseeded red clover, which is a short-lived perennial legume forage crop. Frost-seeding red clover into winter wheat is common for farmers in New York, as it can improve soil health and also be harvested for forage. We selected these treatments to compare the two most promising perennial grain crops to two annual grain crops that farmers are currently growing in the region. Grains were drill seeded at 7.5-in row spacing using the standard seeding rate for each species on September 19, 2016. We aim to test two hypotheses over the next three years: 1) Transitioning fields used for annual grain crop production to perennial grain crop production increases soil health, and 2) Intercropping legume forage crops with perennial grain crops reduces need for nitrogen inputs compared to perennial grain monocultures. In addition to evaluating soil health parameters, we will also be monitoring crop and weed biomass, disease incidence, yield, and grain quality to further inform future development of best management practices for perennial grain cropping systems.

Kernza Conference
The Land Institute hosted a meeting in July 2016 to bring together researchers from around the world who are interested in Kernza. Attendees included plant breeders, geneticists, agroecologists, and producers of grain-based products. Sandra Wayman represented the Cornell Sustainable Cropping Systems Lab and presented on our research. The take-home message from this meeting was that there is strong interest in developing products made from Kernza and more research is needed for management practices. For example, Zachary Golper, baker and owner of Bien Cuit in Brooklyn, spoke about the need to scale up production to support his interest in incorporating Kernza into his products.

Conclusions
Perennial grains are becoming a plausible option for farmers. Although grain yields are still much lower than annual grain crops, harvesting perennial grain for both forage and grain could increase profitability. Additionally, growing perennial crops on land unsuitable for annual crops that require yearly tillage (e.g. sloped land) could make them more attractive to farmers. As with any new crop, we have experienced some challenges in our research including difficulty harvesting grain and weed suppression during the establishment year. However, we remain optimistic about perennial grain crop production in New York and look forward to working with our farmer collaborators to improve production.

Reference Cited
Jackson, W., 1980. New Roots for Agriculture. U of Nebraska Press.

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December 2, 2016
by Cornell Field Crops
Comments Off on Alfalfa-Grass Mixtures – 2016 Update

Alfalfa-Grass Mixtures – 2016 Update

J.H. Cherney, D.J.R. Cherney, and K.M. Paddock
Cornell University

The vast majority of alfalfa acreage in NY is sown with a perennial grass. Until recently, there has been very little research on grass species selection or management of mixtures. We do not know what the optimum percentage of grass should be in mixtures, and it is unclear how consistent grass percentage is across species, varieties and environments.

An informal survey of forage seed companies active in NY in 2014 found timothy to still be over 30% of all forage grass seed sales in NY, with tall fescue and orchardgrass each around 20% of grass seed sales. Eight other grass species make up the remaining 30%, with each of these less than 10% of total seed sales. Forage tall fescue seed sales went from essentially zero 10 years ago to 20% of grass seed sales, and most of it is seeded with alfalfa.

Alfalfa-Grass Ratio in Stands

The primary negative point with mixtures is not lower forage quality, but variable forage quality. The main cause of this variability is a variable alfalfa-grass ratio. Botanical composition of alfalfa-grass fresh and ensiled mixtures is a key parameter for assessing forage and diet quality, as well as for managing mixed stands. Previous attempts to validate near infrared reflectance spectroscopy (NIRS) equations for estimating botanical composition have not been very successful. We collected alfalfa-grass samples from across NY over several years, and Dairy One Forage Laboratory has successfully calibrated NIRS instruments to estimate grass percentage in alfalfa-grass samples.

We are also developing a cell phone app that will estimate grass percentage in the field, by evaluating a cell phone photograph of a mixed stand. Keeping track of grass percentage in alfalfa-grass fields is useful for field and forage management.

Meadow Fescue Potential for Mixtures

Meadow fescue is grown extensively in Canada and Europe, but dropped out of use in the USA decades ago primarily due to reduced yield and disease susceptibility, compared to other grasses. It can be grown in areas suitable for timothy, and is considerably more winter hardy than tall fescue in northern environments. Primarily grown for pasture use in recent decades, meadow fescue has considerable potential in mixture with alfalfa. Alfalfa-grass mixtures are as high or higher yielding than pure alfalfa, and have been shown to be an excellent forage for lactating dairy cattle.

Meadow fescue has higher fiber digestibility (NDFD) than most other grasses, consistently 2-4 percentage units higher than tall fescue. Feeding trials across the USA have shown that a one percentage unit increase in NDFD increases milk production by 0.5 to 1.0 lbs/cow/day, and more than 1.0 lb/cow/day for the highest producing cows. Meadow fescue in combination with new reduced-lignin alfalfa varieties has the potential to produce a very high quality forage for lactating dairy cows. A somewhat reduced yield potential for meadow fescue may actually be advantageous for alfalfa-grass mixtures, where a modest grass percentage is desirable.

2016 Trial Results

Ten grasses [meadow fescue (MF), tall fescue (TF), orchardgrass (OG) and festulolium (Fest.) varieties] were established in binary mixtures with 2 alfalfa varieties in spring 2015 in Oneida and Wyoming Counties. We thank Dave Curtin/Curtin Dairy and Dave Russell/Southview Farms for providing study sites. Optimum rainfall throughout the 2015 season resulted in abundant growth, and three seeding-year harvests were taken at both sites. Cold spring weather in 2016 resulted in immature, very low fiber alfalfa forage under 30% neutral detergent fiber (NDF) and a little over 30% crude protein (CP) when harvested the last week of May, while NDF of grasses was generally optimum in the low 50’s.

Meadow fescue headed out between May 26 and June 1, 2016, depending on variety and location. Tall fescue and festulolium had a similar heading date range, while orchardgrass varieties headed a few days earlier. About half of the grass varieties were at an early heading stage at spring harvest.

Both sites have fertile soils and, in spite of the weather conditions prior to the first two harvests of 2016, averaged a total of 4 tons dry matter/acre. The last three harvests in Oneida County produced good yields, totaling an average of 7.5 tons DM/acre (Fig. 1). Some combinations exceeded 8 tons DM/acre. Severe drought in Wyoming County prevented much regrowth the rest of the year after Cut 2, and reduced total yield to an average of 5.3 tons DM/acre.

Fig. 1. Dry matter yield of alfalfa-grass mixtures at two NY sites in 2016.

Fig. 1. Dry matter yield of alfalfa-grass mixtures at two NY sites in 2016.

With somewhat adequate rainfall at the Oneida County site, grass% was relatively stable or increasing (Fig. 2), tending to decline in late fall, except for MF. Less rainfall on a soil with less water-holding capacity resulted in a decrease in grass% from Cut 1 to Cut 2 in Wyoming County (Fig. 3). The relative ranking of grass% among varieties was generally consistent over locations, but environmental conditions significantly impacted all grasses. Festulolium dropped from 70% grass in Cut 1 to about 10% grass in Cut 3 (Fig. 3), possibly due to drought.

Meadow fescue was relatively inconsistent, with greatly increased grass% later in the year for two of the entries in Oneida County. In Wyoming County, grass% dropped sharply for all entries after cut 1, and then increased significantly for all entries in the late fall after some rainfall returned. Overall, grass% was too high in Oneida County, except for Bariane TF and meadow fescues. Grass% dropped for all entries in the fall in Oneida County, except for meadow fescues.

Fig. 2. Grass% in Oneida County over 5 harvests.

Fig. 2. Grass% in Oneida County over 5 harvests.

Fig. 3. Grass% in Wyoming County over 5 harvests.

Fig. 3. Grass% in Wyoming County over 5 harvests.

Quality Analysis

For Oneida County, averaged over 5 cuts, Hi-Gest360 alfalfa was 4% higher fiber digestibility (NDFD) and 4% lower lignin, compared to Pioneer 55H94. For Wyoming County (3 cuts analyzed to-date), Hi-Gest360 was 8% higher NDFD and 7% lower lignin, compared to Pioneer 55H94. In three seeding year cuts in 2015, Hi-Gest averaged 9% higher NDFD and 8% lower lignin (Oneida); and 5% higher NDFD and 3% lower lignin (Wyoming), compared to 55H94.

As the grass% increases in a mixed stand, there is less nitrogen available to grass from alfalfa, and also more grass requiring the limited available N. As the high-crude protein (CP) alfalfa% decreases, grass CP greatly decreases and total mixed forage CP drops correspondingly. However, CP should remain relatively high in the mixed forage up to at least 40% grass.

Alfalfa averaged 58, 38, 43, 43, and 61% NDFD for 5 cuts. Festulolium was highest in NDFD for all cuts except Cut 2, but was only significantly better than meadow fescue for Cut 1 (Fig. 4). Festulolium headed out after Cut 1, due to moisture stress, greatly reducing NDFD for Cut 2. Cuts 2 & 4 were made about one week too late, resulting in lower NDFD than desired.

Fig. 4. Grass 48h fiber digestibility, Oneida County, 2016.

Fig. 4. Grass 48h fiber digestibility, Oneida County, 2016.

 

Conclusions

Mixtures can increase both yield and quality of forage stands. Grass% in mixed stands is strongly influenced by environmental conditions. Environmental conditions during the establishment phase have a great impact on the alfalfa:grass ratio in succeeding years. Average grass percentage of stands over the 2016 season was double that of the previous fall for both sites.

Grass CP content is greatly impacted by the grass percentage of stands, as a limited supply of available soil N is diluted through increased grass production. As the amount of alfalfa in a stand declines, this also reduces the total supply of available N for grasses. Nevertheless, a mixed stand with up to 40% grass is still likely to have reasonably high CP content.

Results in 2016 indicate that the optimum grass percentage in alfalfa-grass stands at the end of the seeding year may be around 5-15% grass, with about 20-30% in the first production year. A grass percentage as low as 10% can still result in a significant increase in total forage fiber digestibility. Switching from a lower quality grass to a higher quality grass such as meadow fescue may impact forage quality as much as a switch to a higher quality reduced-lignin alfalfa.

Right now our best bet is to first select a site reasonably well drained with near neutral pH and maintain high soil K. In mixture with alfalfa at 12-15 lbs/acre, meadow fescue should be seeded at 4-5 lbs/acre in either the spring as early as possible, or late summer about 4-5 weeks prior to first freeze. Plan to manage it 4×4; 4 cuts/season with a 4” stubble height, with somewhat higher stubble height for the last cut of the season. Meadow fescue often contains a naturally occurring endophytic fungus, but unlike the tall fescue endophyte, no harmful anti-quality alkaloids are produced. Meadow fescue cannot be infected by the tall fescue endophytes, so there are no concerns of livestock disorders with meadow fescue.

Acknowledgment: Alfalfa-grass research was made possible by funding from the New York Farm Viability Institute and the Northern New York Agricultural Development Program.

November 28, 2016
by Cornell Field Crops
Comments Off on Organic Corn Only Yields 7% Lower than Conventional Corn during the Second Transition Year

Organic Corn Only Yields 7% Lower than Conventional Corn during the Second Transition Year

By Bill Cox1, Eric Sandsted1, Phil Atkins2, and Brian Caldwell1
1Soil and Crop Sciences Section – School of Integrated Plant Science, Cornell University; 2New York State Seed Improvement Program

Extremely dry soil conditions in June (0.74 inches of precipitation), exacerbated by a robust red clover green manure crop, resulted in natural crop mortality in late-emerging corn, as well as crop mortality from cultivation in organic corn (photo taken on June 26).

Extremely dry soil conditions in June (0.74 inches of precipitation), exacerbated by a robust red clover green manure crop, resulted in natural crop mortality in late-emerging corn, as well as crop mortality from cultivation in organic corn (photo taken on June 26).

We initiated a 3-year study at the Aurora Research Farm in 2015 to compare different sequences of a corn, soybean, and wheat/red clover rotation in conventional and organic cropping systems with recommended and high input management during the 3-year transition period (2015-2017) from conventional to an organic cropping system. We provided detailed discussions of the experiment (http://blogs.cornell.edu/whatscroppingup/2015/11/09/corn-yield-under-conventional-and-organic-cropping-systems-with-recommended-and-high-inputs-during-the-transition-year-to-organic/) and the timing of management practices in 2016 and weather conditions through July of 2016 in previous soybean articles (http://blogs.cornell.edu/whatscroppingup/2016/07/27/emergence-plant-densities-v3-stage-and-weed-densities-v14-stage-of-corn-in-conventional-and-organic-cropping-systems-in-2016/).

Briefly, a preceding red clover green manure crop (~3.75 dry matter tons/acre) was mowed down on May 18. Dry weather conditions (1.9 inches in March, 1.87 in April, and 1.35 inches from May 1-19), exacerbated by the robust red clover crop, made soil conditions exceedingly dry so plow penetration was difficult in some regions of the fields on May 19. We planted a treated (insecticide/fungicide seed treatment) GMO corn hybrid, P96AMXT, in the conventional system; and its isoline, the untreated non-GMO, P9675, in the organic cropping system at two seeding rates, ~29,600 kernels/acre (recommended input treatment) and 35,500 kernels/acre (high input) on May 20. The high input organic treatment also received the organic seed treatment (in-hopper), Sabrex. We applied Roundup at 32 oz. /acre for weed control in conventional corn at the 4th-5th leaf stage (V4-V5 stage) on June 22 under both recommended and high input management. We also side-dressed the high input treatment with 60 lbs. N/acre. We used the rotary hoe to control weeds in the row in recommended and high input organic corn at the V1-2 stage (June 9). We then cultivated close to the corn row in both recommended and high input organic treatments at the V3 stage (June 15) with repeated cultivations between the rows at the V4-V5 stage (June 22) and again at the V7-V8 stage (July 1). We harvested the crop on November 3 when conventional corn averaged 20.3% and organic corn averaged significantly lower at 19.6% moisture.

Corn plant densities at the V3 stage (June 14), just prior to the close cultivation to the corn row on June 15 but after the rotary hoeing, were relatively low in 2016 (Table 1), undoubtedly because limited rainfall coupled with the robust green manure crop resulted in dry planting conditions. Conventional (70 to 85% plant establishment) and organic corn (75 to 82% plant establishment) had similar plant densities at the V3 stage, unlike 2015 when conventional corn had greater plant establishment. Conventional and organic corn in the high input treatment averaged ~28,000 plants/acre (Table 1), which usually results in close to optimum yield (http://scs.cals.cornell.edu/sites/scs.cals.cornell.edu/files/shared/documents/wcu/WCUvol23no1.pdf). Conventional and organic corn in the recommended input treatment averaged only ~23,500 plants/acre (Table 1), which typically results in yield reductions in most growing seasons. Unfortunately, dry conditions persisted (0.74 inches in June and 1.89 inches in July) so plant densities decreased further by the V14 stage probably because of crop mortality in conventional and a combination of crop mortality and crop damage by cultivation in organic corn. Consequently, conventional corn at the V14 stage (1300 fewer plants/acre or a ~5% decrease from V3 to V14) compared with organic corn (3150 fewer plants/acre or a ~12% decrease) now had greater plant densities (Table 1). Such low plant densities in the recommended input treatment in conventional (~23,000 plants/acre) and organic corn (~21,000 plants/acre) should reduce yields, even in a dry growing season, because of the limited capacity of corn to compensate at low plant densities.

cox-corn-table-1

Weed densities at the V14 stage were also quite low in 2016 (Table 1) because of the lack of significant rainfall events required to initiate weed emergence after cultivations in organic corn or herbicide application in conventional corn. Although weed densities were mostly higher in the organic cropping system, weed densities ranged from only 0.38 to 1.26 weeds/m2 (compared with 1.61 to 3.10 weeds/m2 in 2015), which probably had limited impact on yield. Weed densities in the conventional cropping system ranged from 0.08 to 0.38 weeds/m2, which indicates excellent efficacy of a Roundup application on drought-stressed weeds that emerged after the May 20 planting date and before the June 22 Roundup application.

Conventional compared with organic corn yielded ~7% higher in 2016 (Table 1). Yields, however, were low because of exceedingly dry conditions, including during the critical 2 week period before and after silking (~July 25). Grain yield did not correlate with plant densities at the V3 stage, but had a highly significant correlation with plant densities at the V14 stage (r=0.46, Table 2). Grain yield, however, had virtually no relationship with weed densities in 2016 (Table 2). In 2015, the 20 to 40% lower yield in organic compared with conventional corn in the first transition year (no red clover green manure crop was in place) was associated with lack of soil N availability in organic corn (http://blogs.cornell.edu/whatscroppingup/2015/11/09/corn-yield-under-conventional-and-organic-cropping-systems-with-recommended-and-high-inputs-during-the-transition-year-to-organic/).The 3.5 ton/acre red clover green manure crop probably provided adequate soil N to both organic and conventional corn in 2016 (although the release of N was slow because of the dry conditions). On the other hand, the robust red clover crop probably also contributed in part to the low establishment rates and subsequent low corn yields.

screen-shot-2016-11-28-at-10-24-24-am

Likewise, high compared with the recommended input treatment in corn yielded significantly higher (Table 1). Although not a significant 2-way interaction (p=0.08), high compared with recommended input had a 9.2% yield advantage in conventional corn compared with a 3.2% yield advantage in organic corn. Again, the higher yield in high compared with recommended input, especially in conventional corn, was associated with the higher plant densities at the V14 stage. Despite yielding ~11 bushels/acre higher, the high input compared with the recommended input treatment in conventional corn would not provide greater partial returns at a ~ $4.00/bushel corn selling price because greater seed (6000 more seeds/acre) and N costs (60 lbs./acre of side-dressed N in the high input) offset the greater partial returns.

In conclusion, organic compared with conventional corn yielded ~7% lower in 2016, the second year of the transition from conventional to an organic cropping system. In contrast, organic compared with conventional corn yielded 20-40% lower during the first transition year in 2015 when a green manure crop was not in place. Based on the results of this study, planting a green manure crop to build-up the soil N supply during the first transition year, followed by corn in the second year, is probably a viable strategy instead of planting corn in the first year of the transition period. Corn will follow a wheat/red clover crop as well as soybean (unable to plant wheat after soybean harvest this year because of green stem in soybean and a record wet October) in 2017 so we will be comparing corn in a corn-soybean-corn rotation and in a soybean-wheat/red clover-corn rotation next year. Corn will be eligible for the organic premium in 2017 because 36 months would have elapsed from harvesting conventional spring barley (August), soybean (October) and corn (early November) in 2014, provided we delay corn harvest until the second week of November. Consequently, the inability to plant wheat after soybean harvest this year may be a blessing in disguise because of low current wheat prices and the eligibility of corn for the organic price premium in 2017.

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