Optimizing Use of Grass on Dairy Farms for Environmental/Economic Sustainability

Final Report for LNE94-042

Project Type: Research and Education
Funds awarded in 1994: $118,024.00
Projected End Date: 12/31/1999
Matching Non-Federal Funds: $233,633.00
Region: Northeast
State: New York
Project Leader:
Jerome H. Cherney
Dept of Soil, Crop, and Atmospheric Science, Cornell University
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Project Information

Summary:

A three-year experimental project was initiated to develop and validate best management practices for perennial grasses on Northeast dairy farms, and to promote increased use of perennial grasses for nutrient/manure management and for profitability.

Project Goals:

Initial studies identified optimum forage quality of perennial grasses for dairy cows in a range of balanced rations using information from the Cornell Net Carbohydrate and Protein System model. It is clear from model results that many dairy farmers overfeed nutrients, particularly protein. Model results indicate that optimum grass fiber content is approximately 50-55% neutral detergent fiber, and optimum protein is 18-19% crude protein. Model results were verified with animal feeding trials to convince dairy farmers that grass can produce as much milk as alfalfa in a balanced ration. Feeding trials also indicated that the quality of forage fiber is important in determining dry matter intake and resulting milk production.

Agronomic grass management was studied in three field sites of timothy and reed canarygrass. Timothy stands persisted well over the course of the study at all three field sites, however, reed canarygrass forage averaged over two percentage units higher crude protein than timothy. As a result, timothy use is now being discouraged in New York state. A perennial grass harvest taken in 1998 to evaluate the residual effects of N fertilizer treatments showed that soil potassium was depleted over years in plots receiving more than 120 lbs N fertilizer per acre annually. For reed canarygrass, there appeared to be nitrogen carryover into the following year only in plots receiving the highest rate of N fertilization. Manure applications to grass at two of the sites resulted in significantly lower forage yields than manure plus nitrogen fertilizer. The study was not continued long enough, however, to evaluate the cumulative effects of manure.

A spreadsheet program used to compare economics of grass grown under different cutting managements and fertilizer applications clearly showed that harvest of grass hay with no applicaton of manure or commercial fertilizer is a losing proposition. Farms that currently practice intensive grass management for dairy cattle were sampled to demonstrate that high forage quality was possible on commercial farms. Whole farm nutrient management planning on two of these farms demonstrated that manure nitrogen can be effectively utilized with intensive grass management. It also showed that farms practicing intensive management may have significant P and/or K nutrient balance problems, with excess P and K.

Impacts:

While it is very difficult to document an increase in more efficient grass management for dairy cattle, the interest in efficient grass management has been steadily increasing in New York state. This project has certainly contributed to the increase in awareness of grass as a high quality dairy feed and as a nutrient management tool. Grower/producer/consultant attendance at extension meetings in NYS where grass management was featured from 1995 to 1998 are as follows: 1995: 355; 1996: 758; 1997: 676; 1998: 1164.

Operational Recommendations to Farmers:

Based on project results we are suggesting the following recommendations to farmers:

a. Species selection. Consider reed canarygrass or orchardgrass over timothy (timothy is currently about 70% of the total grass seed sold in New York state) because of the higher level of protein in the forage across all levels of management. An early harvest management that allows for 4 cuttings/season produces a high quality forage that will allow greater flexibility in balancing rations and will optimize milk production of cows fed grass forage.

b. Dry cow management. Results from this study have demonstrated that grass fields managed to produce forage for lactating dairy cows are not appropriate for production of dry cow forage. Set aside grass fields low in available soil potassium and manage them separately for dry cow forage. Harvest grass for dry cows at or after flowering, and use regrowth forage (lowest in K) for cows near calving, when the level of potassium is most critical for animal health. Timothy is consistently lower in potassium than other grasses, while orchardgrass is consistently higher. Fertilize grass fields for dry cow forage adequately with nitrogen, in order to deplete soil reserves of K, and produce economically-acceptable yields.

c. Nutrient management. Farmers are encouraged to practice intensive grass management to aid in overall nutrient management. Nutrients in manure, particularly nitrogen, can be more effectively utilized under intensive grass management.

Project Objectives:

1. To identify the optimum forage quality of perennial grasses for dairy cows to maximize profitability and to verify results through animal feeding trials.
2. To determine the appropriate harvest management to obtain optimum quality of perennial grasses, while maintaining stand persistence.
3. To develop an economic budget to demonstrate the advantages of proper grass and manure management on dairy farms and encourage increased use of perennial grasses.
4. To carry out a case farm study to demonstrate new BMP’s for optimum grass management, including harvest management as well as nutrient/manure management.

Research

Materials and methods:

Objective 2. Sites for N/cutting management of perennial grasses were moderately well drained sites that can support alfalfa as well as grass. Sites represent major segments of NYS crop acres. Sites received N fertilizer and manure treatments through 1997, but were not fertilized in the spring of 1998, with a residual harvest taken in 1998.

Objective 4. We collected forage samples at harvest on 12 primarily grass dairy farms in 1997 and 1998. These participants are located in Chautauqua and Cattaraugus counties in southwestern New York state. A range of soil types are found on all farms, from hilltop and hillside sites to a limited acreage in productive valley areas.

1. Mathew Beckerink has 410 cows and 912 total acres with 41% of the land in hay crops.
2. Randy Burkholder has 50 cows and 259 total acres with 64% of the land in hay crops and 26% in pasture.
3. Roger Clark has 45 cows and 82 total acres with 66% of the land in hay crops.
4. Fred Croscut has 100 cows and 417 total acres with 80% of the land in hay crops.
5. Mike Durow has 100 cows and 184 total acres with 66% of the land in hay crops.
6. Dave Heald has 75 cows and 213 total acres with 68% of the land in hay crops.
7. Charles Peterson has 110 cows and 224 total acres with 61% of the land in hay crops and 4% in pasture.
8. Ken Steward has 100 cows and 247 total acres with 59% of the land in hay crops.
9. Dave White has 125 cows and 225 total acres with 56% of the land in hay crops and 19% in pasture.
10. John Weise has 60 cows and 185 total acres with 100% of the land in hay crops.
11. Jim Beightol has 140 cows and 221 total acres with 53% of the land in hay crops and 20% in pasture.
12. Roger tenPas has 250 cows and 490 total acres with 56% of the land in hay crops.
Research results and discussion:
Project Results

Objective 1. The Cornell Net Carbohydrate and Protein System model was used to estimate optimum grass composition for a variety of dairy cattle rations. Grass-based rations that optimize energy and protein balance to minimize nutrient waste were developed. It is clear from model results that many dairy farmers overfeed nutrients, particularly protein. Model results indicate that optimum grass fiber content is approximately 50-55% neutral detergent fiber (NDF), and optimum protein is 18-19% crude protein (CP). Fields of orchardgrass were established at the Cornell dairy farm in 1994 and were used for three dairy feeding trials. Orchardgrass stands were fertilized with 100 lb of N/acre in the spring of 1997 at greenup, and orchardgrass was harvested at both early and later stages and stored as silage in Agbags. Feeding trials were carried out with both early lactation and mid-lactation cows. Two of the feeding trials involved a relatively large number of animals, with 60 mid-lactation Holstein cows for 10 weeks in one trial, and 50 early-lactation cows for seven weeks in another trial. Milk production from cows fed orchardgrass harvested early consistently resulted in at least as much milk production as with alfalfa. This agrees with recent feeding trials in Ohio comparing alfalfa and grass. Results also indicate that quality of orchardgrass NDF is important in determining dry matter intake and resulting milk production. Milk production differences between diets tended to be larger early in the feeding trials.

Objective 2. Grass stands were successfully established at three sites to determine optimum N fertilization and harvest management to achieve the desired forage quality. Reed canarygrass and timothy were used for these studies. Grasses were managed to achieve a optimum fiber content (approx. 55% NDF) and also a higher than optimum fiber content (60%+ NDF). Five levels of N fertilization (from 0 to 480 lbs) were applied to each species-harvest management combination. The highest rate of N fertilization was required to determine the response function, but is obviously higher than any rate that would be recommended to farmers. Two of the sites also had manure applied to reed canarygrass to assess the N recovery from manure. Nitrogen was split-applied, with all fertilizer applied before 3rd harvest, because weather conditions could preclude a 4th harvest. Harvest at 55% NDF was determined by periodically sampling forage and analyzing for NDF. The late cutting management resulted in 3 harvests per season, while the early cutting management resulted in 4 harvests per season. Average harvest dates over years and locations for the four-harvest system were May 27, June 26, August 10, and September 30. Average harvest dates for the three-harvest system were June 7, July 25, and September 30.

Both grasses responded well to N fertilization, with economic rates exceeding recommended N fertilizer rates. On average, reed canarygrass responded more to N fertilization than timothy. Economic fertilizer N rates for timothy averaged 256 lbs N per acre for 3-harvest management and 287 lbs N per acre for 4-harvest management. Economic fertilizer N rates for reed canarygrass averaged 313 lbs N per acre for 3-harvest management and 346 lbs N per acre for 4-harvest management. Manure applications to grass at two of the sites resulted in significantly lower forage yields than manure plus nitrogen fertilizer. The study was not continued long enough, however, to evaluate the cumulative effects of manure.

The primary difference in fiber content between harvest managements is at the spring harvest. A pattern of first increasing, then decreasing NDF content with increased N fertilization was consistent over years. Over years and locations, CP content of reed canarygrass was consistently higher than in timothy, agreeing with other previous grass trials in the Northeast. Across all N treatments, reed canarygrass averaged over 2 percentage units higher CP than timothy. Nitrate analyses indicated that nitrates were generally not a problem at N fertilizer rates below 240 lbs N per acre, but excessive nitrates were consistently found in grass forage fertilized with 480 lbs N per acre.

A residual harvest was taken in 1998 to assess carryover nitrogen. Nitrogen fertilizer was not applied in 1998. Nitrogen yield in the residual harvest followed similar trends as did dry matter yield. The most N was removed from reed canarygrass plots where no previous N fertilizer had been applied. The most N was removed from timothy plots that received the highest rate of N fertilization in the past. From a nitrogen management standpoint, as well as a forage quality standpoint, reed canarygrass appears to be superior to timothy. Soil analysis of plots in 1998 showed decreasing soil K with increasing N fertilization. Although plots were fertilized with potassium, based on soil test of high N-fertilized plots, soil potassium was depleted over years in plots receiving more than 120 lbs N fertilizer per acre. Plots receiving no N fertilizer increased in soil test K over the entire experimental period. Three-harvest management reduced soil test K values more than four-harvest management.

Objective 3. A spreadsheet program used to compare economics of grass grown under different cutting managements and fertilizer applications clearly showed that harvest of grass hay with no applicaton of manure or commercial fertilizer is a losing proposition. Farms that currently practice intensive grass management for dairy cattle were sampled to demonstrate that high forage quality was possible on commercial farms. Objective 3 is discussed more fully under part C. Economic Analysis.

Objective 4. Twelve farms in southwestern NYS that utilize grass for dairy cattle participated in some aspect of this objective. Farm inputs were collected, including crop yields, crop quality, off-farm feed inputs, soil tests, dairy manure analysis, and the amount of commercial fertilizer and manure applied to each field. These farms have a total of 3,659 acres, averaging 305 acres per farm. Crop enterprises were: corn grain/silage (31%), hay crops (60%), small grains (4%), and improved pasture (5%).

Tables 1 and 2 demonstrate that consistently high quality grass forage can be produced by dairy farmers. The Beightol farm had near optimum forage quality. The Durrow farm had optimum grass fiber content, but CP was too high in 2 of 3 harvests, agreeing with the N surplus found in the estimated within-farm nutrient balance for the Durrow farm below. Grass forage quality of the other farms sampled were generally similar to these two farms, although results were more variable due to slightly less aggressive harvest management.

Whole farm nutrient management planning on two of these farms demonstrated that manure nitrogen can be effectively utilized with intensive grass management (Appendix Tables 3-6). It also showed that farms practicing intensive management may have significant P and/or K nutrient balance problems, with excess P and K. Tables 3 and 5 show actual results, including all fertilizer applications by the participants. Tables 4 and 6 show estimated within-farm nutrient balance if manure nutrients were allocated prior to determination of fertilizer requirements. The Durrow farm had much better utilization of manure nutrients by following the program suggestions. Even when manure utilization was optimized, significant surplus of both P and K remained on both farms.

Participation Summary

Education

Educational approach:
Dissemination of Findings

Grass management presentations at extension meetings to discuss results obtained in this study and to promote the effective use of grasses have been held throughout the period of the study and will continue to be held in the future. The number of meetings and the attendance continues to increase at grass-related events. A full day Quality Forage Forum on March 2, 2000 is being sponsored by five western NY counties, including the counties that are home to the farmer participants in this study.

Specific feeding trials were presented at scientific meetings during the period of the study, and a summary of the economic and nutrient management implications of the study are planned for both the Agronomy and Dairy Science society annual meetings in 2000.

Two of the PI’s (J.H. Cherney and D.J.R. Cherney) co-edited a book for CAB International published in November, 1998 entitled “Grass for Dairy Cattle”. The book highlights the importance of grasses in grazing and nutrient management, particularly in relation to the dairy industry, and utilizes some of the results from this study.

Due to this successful study with grass for dairy cattle, we have obtained additional funding from Cornell University to conduct feeding trials in late 1999 to compare tall fescue, orchardgrass and alfalfa. Tall fescue has been agronomically superior to other grass species in recent trials, but feeding quality is not clear. Following these feeding trials, we are planning on summarizing all the field data and feeding trial data from this study and other studies in NYS, and also including relevant grass data from other NE states, to produce a NE publication on “Grass for Lactating Dairy Cows” in 2000. Preliminary discussions regarding the publication are underway, and the publication also will include SARE data from studies undertaken by Miner Institute, Chazy, NY.

Publications

Cherney, D.J.R., J.H. Cherney, and L.E. Chase. 1998. Lactation performance of Holstein cows fed orchardgrass silage. J. Dairy Sci. 76 (Suppl. 1):207.

Jonker, J.S., D.J.R. Cherney, D.G. Fox, L.D. Chase, and J.H. Cherney. 1997. Orchardgrass utilization by lactating dairy cows. In. Proc. Amer. Forage and Grassld. Council 6:148-152.

Jonker, J.S., D.G. Fox, D.J.R. Cherney, J.H. Cherney, and L.E. Chase. 1996. Dry matter intake and nitrogen balance in mid-lactation Holstein cows as influenced by forage NDF source. J. Dairy Sci. 79(Suppl 1):233. Annual ADSA meeting, 1996.

Jonker, J.S., D.G. Fox, D.J.R. Cherney, J.H. Cherney, and L.E. Chase. 1996. Forage NDF source effects on milk production in mid-lactation Holstein cows. J. Dairy Sci. 79(Suppl 1):150. Annual NEADSA meeting, 1996.

Jonker, J.S., D.G. Fox, and D.J.R. Cherney. 1995. Influence of grass protein fractions on estimated allowable milk. J. Dairy Sci. 78(Suppl 1):207. Annual ADSA meeting, Ithaca, NY. June 26-28, 1995.

Cherney, D.J.R. and J.H. Cherney. 1995. Grass forage quality and digestion kinetics as influenced by maturity and N fertilization. J. Dairy Sci. 78(Suppl 1):207. Annual ADSA meeting, Ithaca, NY. June 26-28, 1995.

Cherney, D.J.R. and J.H. Cherney. 1995. Effect of nitrogen supplementation on in vitro digestion kinetics of perennial grasses. 23rd Biennial Conf. on Rumen Function 23:7. Chicago, IL. Nov. 14-16, 1995.

Klausner, S.D., J.H. Cherney, R.F. Lucey, and W.S. Reid. 1998. Nitrogen fertilization of grasses. Dept. of Soil, Crop & Atmospheric Sciences Research Series No. R98-1.

Project Outcomes

Impacts of Results/Outcomes

Potential impacts of this project are difficult to quantify. Intensive grass management will without question (1) protect soil from erosion, (2) reduce chemical usage, and (3) increase income per acre. This project has directly resulted in an increase in intensive grass management in NYS and some shift of alfalfa and corn acreage to perennial grass.

1. Protect soil from erosion. Encouraging the use of grass, particularly in place of row crops, will dramatically reduce erosion on sites with significant erosion potential. Proper species selection for persistence also will ensure adequate ground cover over the life of the stand and maximize protection from erosion.

2. Reduce chemical usage. Although not a goal of this program, there has been a shift in some acreage from high chemical usage crops, such as alfalfa and corn, to very low chemical usage perennial grass. This is difficult to quantify. Extension specialists in most NYS counties have reported farmers shifting from alfalfa/corn to perennial grass acreage in the past three years, none have reported farmers shifting from grass to alfalfa/corn. Alfafa/corn acreage statewide has not declined presumably because large farm operations that bring idle land back into production will typically plant alfalfa/corn.

3. Increase income per acre. With intensive management and recommended manure and fertilizer applications using our spreadsheet program, returns over all production costs from 1994 to 1997 (Mt. Pleasant location) averaged $217 per acre more than the typical extensive grass management practiced in NYS.

Economic Analysis

Objective 3. Grass management methods were compared using a spreadsheet program developed by Darwin Snyder of Agrecord Management Services. Yield and quality data from each year of the study at the Mt. Pleasant, NY location for timothy and reed canarygrass were included in the analysis, and separate results were generated for hay and silage use, as well as with and without manure credits. Value of hay and silage crops was estimated using the latest version of the FORVAL program with current crop prices, developed by Gary Fick, Cornell University. Hay crop value was based on nutrient content and on current market prices for hay, grain and protein sources. Nutrient content of the forage is based on a weighted average of each forage quality parameter across all harvests. Establishment, maintenance and harvest costs are used for each harvest management/N fertilizer management combination to generate net return per acre for each method. Returns also were estimated with manure included as a fertilizer source.

As with any economic analysis, results can be dramatically affected by the assumptions made. Assumptions regarding variable and fixed costs are based in part on information taken from the annual New York Economic Handbook. The assumption of greatest concern, however, is the estimated feed value per ton, based on FORVAL. Detailed budgets were included in past annual reports.

Three years of results indicate that grass managed without some form of nitrogen fertilization will not be profitable. This project demonstrated that managed grass is profitable, and is more profitable the higher that grain prices rise. When grain prices were low, as in 1998, three-harvest management with its higher yields appeared to be more economically feasible than four-harvest management.

Optimum management, including crediting manure nutrients, resulted in positive returns per acre, except in years where drought reduces crop yield below that of the current state average for hay crops, such as 1995. In 1995, optimum fertility management resulted in returns over all production costs of -$85 per acre for four-harvest management and -$64 per acre for three-harvest management. Lack of N fertility management with perennial grass always resulted in large negative returns per acre. Yield variation from year to year resulted in returns over all production costs from 1994 to 1997 also varying from -$64 per acre in 1995 to $189 per acre in 1996. Results clearly indicate that only intensive management will be profitable, and only in years without severe drought.

The primary risk involved in shifting forage production to intensively managed grasses is the risk of drought. Grasses are not as productive as legumes under drought conditions. Nitrogen fertilization will be unprofitable if moisture stress severely limits yields. A full analysis of this risk is a project by itself, and is included as a suggested new area for study in Section 7 below.

Farmer Adoption

A. Changes in Practice

Based on the large turnout at meetings featuring grass management and the comments from county extension educators, it appears that improved grass management is being adopted by many farmers in New York State. The new CAFO regulations have mandated nutrient management plans for some NYS dairy farmers and have caused many more dairy farmers to critically evaluate their nutrient management practices. This has forced more farmers to consider increasing grass acreage to help address nutrient management challenges. As more farmers move to intensive grass management, other farmers are gradually changing their attitude about grass and high producing dairy cows. This study proved to be very timely as it allowed us to produce a significant database on intensive grass for dairy cows just as the need for this information was greatly increasing, fueled by nutrient management issues.

B. Operational Recommendations

Based on the results of this project we are suggesting the following recommendations to farmers:

1. Species selection. Consider reed canarygrass or orchardgrass over timothy (timothy is currently over 70% of the total grass seed sold in New York state) because of the higher level of protein in the forage across all levels of management. Obtain soil-specific species recommendations in NYS using a world-wide web program at http://www.forages.org.

2. Lacating cow management. An early harvest management that allows for four cuttings per season produces a high quality forage that will allow greater flexibility in balancing rations. Grass forage quality should be determined based on fiber content, with optimal fiber content of 50-55% neutral detergent fiber. Appropriate manure and/or commercial nitrogen fertilizer applications will result in satisfactory crude protein content in grass forage.

3. Dry cow management. Grass fields managed to produce forage for lactating dairy cows are not appropriate for production of dry cow forage. Set aside grass fields low in available soil potassium and manage them separately for dry cow forage. Harvest grass for dry cows at or after flowering, and use fall regrowth forage (lowest in K) for cows near calving, when the level of potassium is most critical for animal health.

C. Producer Involvement

Number of growers/producers/consultants in attendance at Extension area meetings where grass management was featured (final totals for each year):
1995: 257
1996: 758
1997: 676
1998: 1164
These totals do not include inservice extension training sessions during the four year period, at which grass management was always included.

Percent of growers/producers/consultants at specific types of meetings from 1995 to 1998:
Workshops 19%
Conferences 63%
Field Days 7%
CCA Training 11%

Farmer Evaluations

One indication of farmer interest in intensive grass management is indicated by producer involvement in meetings where intensive grass management was featured over the duration of the study. Attendees at meetings (see part 6) increased well over 300% from 1995 to 1998 and attendance has not yet peaked.

A two page survey sent to 12 participating farmers in southwestern New York, determined their current attitudes concerning grass for dairy cattle.The distribution of grass species sown on these southwestern NY dairy farms showed that timothy was grown on only 4% of the hay acreage, and acreage of reed canarygrass was over 600% higher than timothy and acreage of orchardgrass was over 500% higher than timothy. This reflects our current recommendations of reed canarygrass and orchardgrass over timothy. Even tall fescue acreage on these farms was twice that of timothy. Statewide these figures are reversed, however, with timothy dominating grass seed sales, representing about 70% of the total grass seed sold in NYS.

One of the farmers involved in the grass sampling project is Mike Durow, Randolph, NY, who is milking 126 cows 2 times per day without BST, and has a 20,700 DHI herd average.
Mike stated: “”I like grass forages. I’d rather have grass than alfalfa. My dairy nutritionist says he can adjust a ration based upon grass forage more easily than one based upon alfalfa.” and
“I think grass hay production is cheaper than alfalfa. I had to spray all my alfalfa for leafhoppers. I can put my dairy manure on the grass hay fields. Grasses can also adjust to lower soil pH.”

Areas needing additional study

1. Economic risk assessment dealing with the variability of grass yields related to weather extremes from season to season.

2. Investigation of legume species to be sown in mixture with perennial grasses, particularly for pasture. There is great need for a productive, persistent pasture legume for the Northeast.

3. Soil-specific forage species recommendations (grasses and legumes) to produce forage for specific uses, including pasture. Data accumulated here, along with other sources of data, can be used for this purpose, and we have developed a prototype program for NYS.

4. Whole farm nutrient management analysis in this study has indicated that dairy farms may have some very significant problems related to utilization of manure nutrients. The foundation of nutrient management planning software should include soil-specific forage species recommendations. This issue is not currently being effectively addressed in any of the many nutrient management packages under development.

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.