Eastern Gamagrass Determining its Feasibility as a Forage Crop for the Northeast

Final Report for LNE97-096

Project Type: Research and Education
Funds awarded in 1997: $108,252.00
Projected End Date: 12/31/2001
Matching Federal Funds: $41,089.00
Matching Non-Federal Funds: $89,488.00
Region: Northeast
State: New York
Project Leader:
Paul Salon
USDA-NRCS
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Project Information

Summary:

Eastern gamagrass is a perennial warm season grass which can be used for hay, haylage and in managed pasture situations. It is a highly productive, palatable and digestible forage which may have use on dairy farms. Its use on steeper slopes instead of corn silage will reduce soil erosion with its associated water quality problems. Eastern gamagrass cv. “Pete” was established on 12 different sites including 8 farms and 4 teaching and/or research facilities within 9 counties in New York State.

The objectives of the project were to:

1. Evaluate the adaptability and yields of eastern gamagrass grown on a variety of soil types.

2. Evaluate the compatibility of eastern gamagrass grown with several nurse/companion crops.

3. Evaluate the forage quality of eastern gamagrass grown at the USDA-NRCS Big Flats Plant Materials Center, Corning, NY.

4. Conduct feeding trials comparing eastern gamagrass with corn silage as a significant portion of a dairy ration.

5. Assess the on farm economic implications of utilizing eastern gamagrass as a significant component in a dairy ration compared to corn silage.

Companion plantings were investigated to reduce erosion during establishment, to reduce frost heaving problems, add nitrogen and to improve forage quality. Companion plantings of oats and 5 legumes were established in sub plots at all sites immediately following cultivation at the end of July to early August. The legumes were: white clover, red clover, alfalfa, birdsfoot trefoil, and black medic.

All of the companion crops established well and provided good erosion control in the fall and winter, there were also a lot of annual weeds that provided some erosion control earlier in the season. The companion crops persisted well into the 3rd year with percent cover in mid June for alfalfa, white clover, red clover and birdsfoot trefoil of 74.5, 95.3, 96.5, and 78.5 % respectively. In some situations the cover crops were outcompeted by perennial grasses. When fully established they competed well against annual weeds. As the covers decline weed infestation becomes a problem which may need a herbicide application to control.

Of the 12 sites 8 are excellent with dense rows of gamagrass, 4 are fair to good. It appears that initial stand density is extremely important in competing with weeds and companion plants. There was no competition between the companion crops and the gamagrass during the establishment year, the second year (1999) due to a drought resulted in above normal competition. In 2000 we had abnormally cool temperatures which reduced gamagrass yields and increased competition from cool season legumes. There were significantly higher eastern gamagrass yields in the area outside of the companion crop study areas which had additional weed control. The eastern gamagrass yields in these areas at Cornell, Cobleskill , Lathrope farm and the Bog Flats Plant Materials Center, for two cuttings were: 2.11, 2.99, 2.75, 3.75 dry matter tons/ac respectively. The perennial companion crops competed with the eastern gamagrass reducing yields compared to the control. Eastern gamagrass yields were reduced by the perennial companion crops. The gamagrass yields when grown with alfalfa, white clover, red clover and birdsfoot trefoil were 71.5, 66.8, 78.0, and 82.5% of the control respectively. The oats were not competitive with the gamagrass and provided good winter cover for erosion control and potential frost heaving protection.

In order to determine the value of eastern gamagrass grown in the Northeast a forage quality study was conducted at the Big Flats Plant Materials Center. Forage quality samples were taken on a mature stand of eastern gamagrass cv. “Pete”. The plots were cut at three first cutting dates, starting on 6/13/97 and 5/28/98 and taken at 3 weekly intervals. A second cutting was sampled at 3 intervals of 4, 5 and 6 weeks. The average forage quality for the best 1st cutting dates for both years for CP, NDF, ADF, lignin, dig. NDF and IVTD were 14.8, 70.7, 32.5, 3.0, 73.6, and 80.7% respectively. The quality of the 1st and 2nd cutting decreased as maturity of the forage increased. A 5 week cutting interval is recommended. The information obtained from this study will be used in a computer model to decide on a gamagrass based dairy ration to test with animal feeding trials. Feeding trials comparing eastern gamagrass with corn silage were conducted at SUNY Cobleskill, Morrisville and the Cornell T&R Center. Diets were balanced for fiber, total protein, energy and minerals. There was more grain used in the gamagrass diet. There was no significant differences in dry matter intake, milk production, and milk composition between the diets. This study indicates that gamagrass can be used to replace the fiber coming from corn silage.

ABSTRACT

Eastern gamagrass, Tripsacum dactyloides (L.) is a perennial, warm season grass that is being developed as a forage crop. Companion planting with legumes would be beneficial for reducing erosion, adding nitrogen, improving yield and quality and for weed control. Alfalfa, birdsfoot trefoil, black medic, red clover, white clover and oats were interseeded into newly established gamagrass after cultivation at the end of July, 1998. Four locations with in New York State will be reported on. The first harvest year, 1999 was extremely dry and the cover crops competed with the gamagrass. The percent of yield in 1999 compared to the control for the alfalfa, black medic, oats, red clover, birdsfoot trefoil and white clover was 58%, 73%, 100%, 60%, 79% and 58% respectively. The percent of yield in 2000 compared to the control control for alfalfa, black medic, oats, red clover, birdsfoot trefoil and white clover was 70%, 92.8%, 100%, 96%, 77%, 83%, and 75% respectively. The area outside of the plots had additional weed control of Roundup 2qts/ac in early spring following establishment as a dormant spray and 2,4-D 1 qt/ac to control broadleaf weeds. These areas outperformed the study plot by 184%. Due to the very growing season in 2000 the yields were low ranging from 1.9 to 3.75 tons/ac.

Introduction:

Eastern gamagrass, Tripsacum dactyloides (L.), is a tall perennial warm season (C4) native grass. Eastern gamagrass is a highly digestible and can be used as mechanically harvested and grazed forage. Eastern gamagrass is slow to establish and is grown in rows (30-36 inches) wide. On steeper slopes soil erosion during establishment would be reduced if rows were interseeded with a companion crop. Companion planting with legumes would be beneficial for reducing erosion, adding nitrogen, improving yield and quality and for weed control. Due to the slow establishment of eastern gamagrass the companion crops were established about 2 months after the eastern gamagrass to avoid early competition. This study evaluates the performance of ‘Pete’ eastern gamagrass with 6 companion crops when grown in New York State. Legumes have been successfully grown with warm-season grasses in the southern USA to extend the growing season (Evers, 1985). Posler er al. (1993) observed greater yields in Kansas with five of six native, legume-switchgrass mixtures compared with unfertilized switchgrass. Marten (1989) suggested that warm-season grasses may be incompatible with cool-season legumes because of differences in growth habit, relative maturity, harvest schedules, and poor persistence. A study was conducted in Iowa by Bettle et.al.1996, frost-seeding legumes into established switchgrass , they reported similar results with increase in overall yields of the grass and legume mix at the expense of the grass component.

Project Objectives:

• To evaluate the yield of eastern gamagrass grown on farms in New York.

• To evaluate the effects of the companion crops on the yield of eastern gamagrass.

• To evaluate the effects of the gamagrass and weeds on the persistance of the companion crops.

• To evaluate the effects of the companion crops on the weeds.

Research

Materials and methods:

Site Characteristics:

The data presented comes from 4 locations in New York. Three of the sites were in corn for at least two years prior to seeding with the eastern gamagrass. The Big flats side was in Cereal rye production the previous year.

1. Cornell T&R center in Dryden, NY at an elevation of 400 m on a Howard gravelly silt loam, 0-2% with a pH of 6.7 with high P&K soil test levels.

2. Cobleskill Ag. & Tech. College in Cobleskill, NY at an elevation of 290 m on a Tioga silt loam, 0-2% with a pH of 6.7 with high P&K soil test levels.

3. Rogers Center in Sherburne, NY at an elevation of 350 m with a southern aspect on a Valois gravelly silt loam, 6-8% with a pH of 6.4 with high P&K soil test levels.

4. Big Flats Plant Materials Center, Corning, NY at an elevation of 290 m on a Unadilla Silt loam, 0-2%, with a pH of 5.8 with medium P and low K soil test levels.

Plant Materials:

‘Pete’ eastern gamagrass with 58% quick germination and 23% dormant seed with 12 weeks of stratification was used for the study. The gamagrass was planted at 5-6 seeds/ft or approximately 15 bulk lbs/ac using corn planters at a depth of 1.5 –2.0 inches with row spacings of 30-32 inches.

Within the field plantings small plots of 5 rows by 30 ft were hand sown to companion crops following cultivation. The planting dates for the gamagrass and companion crops per location are in Table 1. The species, cultivars and rates of the companion plants are in Table 2. There were 4 replications per site in a randomized block design.LNE

I . Evaluate the adaptability and yields of eastern gamagrass grown on a variety of soils

Eastern gamagrass CV. “Pete” was established on 12 different sites including 8 farms and 4 teaching and/or research facilities within 9 counties in New York State. Ten of the sites were in corn silage the year before. Eastern gamagrass seed requires stratification, a moist prechilling period, of six to eight weeks. One seed company sells the seed dry with a Germtech treatment, which has been successful. Due to the large crowns, eastern gamagrass is planted in 30-36 inch rows to facilitate machinery harvest. Eastern gamagrass is seeded with a corn planter at 1.5 inch depth. The best results were obtained with finger pick mechanism units, and with plate planters with holes large enough to allow multiple seed drops. An air planter was successfully used with one planting it is recommended that a seed meter be used since they are reported to clog. Some problems were encountered using a grain drill with the uniformity of flow and shallow seed depth placement. When using a grain drill several of the holes were blocked to obtain the desired row spacing. It is recommended to surface dry the gamagrass seed to facilitate flow when using corn planters with a plate or with a grain drill. Cultipacking after using a grain drill is recommended. It is important to plant eastern gamagrass early, at the beginning of corn planting season, to take advantage of the soil moisture. A seeding rate of 15 lb/ac was used in 1998 up from 10 lb/ac used in 1997 to help reduce competition from the weeds and to facilitate cultivating. The eastern gamagrass seed used had 58% germination with 28% dormant seed with 12 weeks of stratification. When choosing eastern gamagrass seed it is important to look at the germination rate and not just the pure live seed (PLS) on the tag which combines the germination with the dormant to come up with a total viable seed. The germination rate can vary greatly within the same PLS rating for different seed lots. No fertilizer is applied during the initial planting year except some starter fertilizer through the planter to prevent the weeds from benefiting from the fertilizer. It is important to start with a site that has been cleared of perennial weeds by a suitable crop rotation, smother crop or a fall or a spring Roundup application. In the Northeast no-till sod seedings are very risky due to cool soil conditions and potential slug and other insect damage. The use of 2,4-D, mowing and cultivation are alternatives for weed control since at this time no residual herbicides are registered for this crop. Cultivation with a row crop cultivator proved extremely useful and could be used in place of 2,4-D, mowing above the gamagrass canopy is another option. The following spring Roundup was spot applied where needed to control quackgrass and other cool season grasses prior to the gamagrass green-up in mid April.
The soils varied at each site and in most cases more than one soil type was represented in each of the fields. These sites were evaluated by an NRCS area soils resource specialist to spot check the soil map and to take samples for analysis for particle size, organic carbon content, CEC, and pH. Seventeen different soil types were identified from soil maps and on site investigations. Yields were obtained by cutting 10 ft of row with 4 replications. The entire sample was dried to determine dry matter yields.

II. Evaluate the compatibility of eastern gamagrass grown with several companion crops

Companion plantings of five legumes and oats were established in sub plots at all sites immediately following cultivation at the end of July to early August. Companion plantings would be beneficial to reduce erosion in the fall of the establishment year, adding nitrogen, improving yields and forage quality. Eastern gamagrass is noted to start growth earlier than most warm season grasses. We wanted to investigate the compatibility of the perennial cool season legumes with the gamagrass, to determine which species would persist with the least competition to the gamagrass. The legumes were: white clover, red clover, and black medic at 10 lbs/ac alfalfa at 15 lbs/ac, and birdsfoot trefoil at 12 lbs/ac the cultivars are given in Appendix 11, Table 2. The subplots (5 rows by 30ft) were hand broadcast on the surface immediately following cultivation with no cultipacking, allowing the rain to wash the seed into the soil. There were four replications organized in a randomized block design. To evaluate the competition between the gamagrass and the companion plantings, four sites were chosen which had excellent gamagrass and companion plant stands. See Appendix 11, Table 1 for a description of the sites, and planting dates. Evaluations were made on eastern gamagrass for population, height and tiller number for each of the eastern gamagrass companion crop combinations, the establishment year. The companion crops were evaluated for % companion crop and % weed cover, and each plot was evaluated for total % cover. Biomass measurements were made of the oats the first year and for the legume covers the beginning of the second year and at gamagrass harvests. The gamagrass was cut for biomass measurement the second year (1 cut) and the third year (2 cuts).

III. Evaluate the forage quality of eastern gamagrass at the USDA-NRCS Big Flats Plant Materials Center

Two forage quality studies were conducted in 1997 and 1998. A time of cutting study was conducted on an established 6-year-old stand of eastern gamagrass, cultivar ‘Pete’, on a Unadilla silt loam soil at Big Flats, New York. The stand received 100 lbs ac-1 yr-1 of nitrogen on June 4, 1997 and May 27, 1998. Three replicated plots were harvested (4 individual plants per rep) at three 1¬st cutting dates, starting on 6/13/97 and 5/28/98 and taken at weekly intervals. A second cutting was sampled at three intervals, four, five and six weeks. A second forage quality study was conducted evaluating the vegetative and reproductive tillers of six agronomically superior accessions and ‘Pete’. Four individual plants were sampled at the three 1st cutting dates for each accession. The samples were analyzed for percent: CP, NDF, ADF, lignin, dig. NDF and IVTD. An evaluation of the rate of NDF digestion (invitro digestion kinetics) was conducted was conducted on the second cuttings of the time of cutting study using “Pete” eastern gamagrass. The Lab procedures were conducted at Cornell University and are outlined in appendix 12.

IV. Conduct on farm feeding trials comparing eastern gamagrass as a significant portion of a dairy ration

Three production trials were conducted to determine the role of Eastern gamagrass in the feeding of lactating cows. The trial was conducted with 16 lactating Holstein cows (165.2 ± 8.7 DIM) milked three times daily at Cornell University and with 10 and 14 lactating Holstein cows milked twice daily at SUNY-Cobleskill an SUNY–Morrisville. The Cornell University (CU) trial was a continuous trial with production parameters of the previous week used as a covariate. The SUNY-Cobleskill and Morrisville trial was a switchback design with 28 d periods.

Research results and discussion:

The eastern gamagrass yields in 2000 were lower than usual due to far below average temperatures in the region. Above average precipitation may also have reduced available nitrogen. There were significantly higher eastern gamagrass yields in the area outside of the study areas which had an early Spring dormant Round-up treatment and 2,4-D to help control broadleaf weeds. The eastern gamagrass yields in these areas at Cornell, Cobleskill, Rogers Center and Big Flats Plant Material Center for two cuttings were: 2.11, 2.99, 2.75 and 3.75 tons/ac respectively. Cornell was cut one week earlier than the Rogers Center and was on very well drained soils which may have been effected by the previous years drought . Big flats forage was cut later than the rest, which may have accounted for the larger yield.

The perennial companion crops competed with the eastern gamagrass reducing yields compared to the control. There were significant differences on the drier site at Cornell for alfalfa, white clover and red clover for both cuttings and birdsfoot trefoil for only the first cutting (Table 4 and Fig. 3). The other sites were not significant at P=.05 but the trends were the same for alfalfa and white clover (Tables 3, 5 & 6, Fig. 2 ,3 & 4). The oats were not competitive with the gamagrass and provided excellent winter cover for erosion control and potential frost heaving protection.

All of the companion crops established well and provided good erosion control in the fall and winter, there were a lot of annual weeds that provide some erosion control earlier in the season. There was no competition between the companion crops and the gamagrass during the establishment year, the second year due to a drought and the earlier start of the legumes resulted in above normal competition. The most persistent companion crop was white clover with percent cover at Cornell, Cobleskill, Rogers Center and Big Flats in mid June of (90.0, 99.5, 98.8 and 93.0%). The red clover persisted well at Cornell, Cobleskill and Big Flats (96.8, 98.8 and 94.0%) but was grazed out by deer early at the Rogers Center. The alfalfa and birdsfoot trefoil did well at all sites. See Tables 6-8 for the data. All of the companion crops were reduced during the August evaluation but some will probably come back during the fall. There was a positive relationship between the cover of the companion crops and annual weed suppression but they were also competitive against the eastern gamagrass. As the covers decline weed infestation becomes a problem which may need a herbicide application to control. The establishment of companion crops during the second year may be an option on soils not prone to erosion to avoid competition during the second year.

I . Evaluate the adaptability and yields of eastern gamagrass grown on a variety of soils

Due to several reasons mostly due to planter problems or weed control not all stands were successful and were not evaluated. Due to variability in planting density attributed to differences in types of planters used, soil moisture at time of planting and differences in weed pressure much of the differences in yields can not be attributed to soils. A listing of yields and soils are listed in Table 1. These yields are lower than would have been expected due to the extremely dry summer in 1999 and the extremely cool summer in 2000. There was also some residual biomass available that could in some years be taken as a third cutting which would improve yields. Eastern gamagrass suffered from damage due to heavy equipment dual wheeled large tractors harvested when the soil was wet. When smaller equipment was used damage was not excessive.

II. Evaluate the compatibility of eastern gamagrass grown with several companion crops

The eastern gamagrass yields in 2000 were lower than usual due to far below average temperatures in the region. Above average precipitation may also have reduced availabilty of nitrogen. There were significantly higher eastern gamagrass yields in the area outside of the study areas which had an early spring dormant Round-up treatment and 2,4-D later in the season to help control broadleaf weeds. In 1999 with one cut the yields ranged from 1.5 – 2.5 tons/ac without companion plants in a very dry year. The eastern gamagrass yields in these areas at Cornell, Cobleskill, Rogers Center and Big Flats Plant Material Center for two cuttings in 2000 were: 2.11, 2.99, 2.75 and 3.75 dry matter tons/ac respectively. Cornell’s yield was lower due to being cut one week earlier than the Rogers Center and was on very well drained soils, which may have been effected by the previous years drought. Big Flats forage was cut later than the rest, which may have accounted for the larger yield. See appendix 11, Tables 3 – 6 for cutting dates. Depending on the season a 3rd cut may be possible to increase yields. Due to differences between sites due to soils, fertilizer and harvest timing, and weed pressure the sites were analyzed separately.
There was no competition between the companion crops and the gamagrass during the establishment year, the second year due to a drought and the earlier start of the legumes resulted in competition. The third year was cooler than normal and favored the cool season legumes. The perennial companion crops competed with the eastern gamagrass reducing yields compared to the control. There were significantly lower eastern gamagrass yields in 2000 on the drier site at Cornell for the alfalfa, white clover and red clover companion plots for both cuttings and birdsfoot trefoil for only the first cutting. The reduction in gamagrass yields for two cuttings from the control due to the above companion crops at Cornell were 51, 80, 77 and 74% respectively (Appendix 11, Table 4). The average reduction from all sites due to the above companion crops were 71.5, 66.8, 78.0, and 82.5% respectively (Appendix 11, Table 3-6). At the Big Flats site there were significantly lower eastern gamagrass yields for the alfalfa, white clover and red clover companion plots for 1st cutting and red clover and white clover companion plots for the 2nd cutting (Appendix 11, Table 6). At the Rogers Center and Cobleskill there were no significant differences but the trends were the same for alfalfa and white clover (Appendix 11, Tables 3 & 5). The oats were not competitive with the gamagrass and provided excellent winter cover for erosion control and potential frost heaving protection. The first year it would be beneficial to clip the planting in mid June, harvest if possible the legumes, to assist in alleviating competition from the legumes on the gamagrass. It appears that initial stand density is extremely important for the gamagrass to compete with weeds and companion plants. The companion legumes at the four sites increased overall yields (Appendix 11, figures 1-4).
All of the companion crops established well and provided good erosion control in the fall and winter. The total cover on most sites which included the gamagrass, companion plants and weeds resulted in 90% cover going into the winter, which would provide adequate erosion control. The rate of oats should be reduced to 1-1/2 bu when planting in late July-early August to prevent excessive mulching over the gamagrass plants. There were a lot of annual weeds that provided some erosion control earlier in the season. On extremely steep sites, especially in areas of concentrated water flows erosion can be a problem during early establishment and no-till methods may need to be investigated. The companion crops, in some situations can be overwhelmed by cool season perennial grasses.
The most persistent companion crop was white clover with percent cover at Cornell, Cobleskill, Rogers Center and Big Flats in mid June of (90.0, 99.5, 98.8 and 93.0%). The red clover persisted well at Cornell, Cobleskill and Big Flats (96.8, 98.8 and 94.0%) but was grazed out by deer early at the Rogers Center. The alfalfa and birdsfoot trefoil did well at all sites. See Appendix 11, Tables 7-10 for the data. All of the companion crops were reduced during the August evaluation they will probably come back during the fall. There was a positive relationship between the cover of the companion crops and annual weed suppression but the companion crops were also competitive against the eastern gamagrass. As the companion crops decline weed infestation becomes a problem which may need a herbicide application to control, removing the balance of the companion crop. The establishment of companion crops during the second year may be an option on soils not prone to erosion to avoid competition during the second year. Reducing the spacing of the gamagrass to 15-16 inches and frost seeding the legumes may also be an option. At a site at SUNY Morrisville several cool season grasses were interseeded, all were overly competitive the following spring and judged not suitable as companion plants. Cereal rye was sown and if harvested early the following spring did not overly compete with the gamagrass and is worthy of further investigation.

III. Evaluate the forage quality of eastern gamagrass at the USDA-NRCS Big Flats Plant Materials Center

The NDF, ADF, and lignin all increased with advancing initial spring harvest date while IVTD and dNDF declined in first cutting samples (Appendix 12, Table 1). The CP content of eastern gamagrass was not as influenced by harvest date as were the other variables with no differences detected in 1998 (p>.05). In 1999 there was a difference from 16.4 to 15.9%. There were significant differences for most variables measured between first cutting dates so that timing appears as important in gamagrass as in most perennial forages. The NDF was relatively high in comparison to perennial cool season grasses grown in NY but digestibility of both dry matter and NDF was high. The CP in both years was higher than those reported in other studies from the South and Midwest, (see Appendix 12). This data suggests that acceptable forage quality can be achieved with proper management.
Second-cutting samples were affected by initial harvest date and cutting interval, the range in NDF between cutting regimes was not large in either year (Appendix 12, Table 4). The mean crude protein was clearly reduced for the six week second cutting interval regardless of the first cutting date (Appendix 12, Table 4). The CP for second cuttings was lower than for first cuttings. There was no topdressing following first cutting. Initial first cutting date had no effect on regrowth IVTD and dNDF in 1997 (Appendix 12, Table 5). In 1998, delaying initial harvest resulted in lower second cutting IVTD and dNDF. Differences between years are likely due to environmental differences. Increasing cutting interval decreased IVTD and dNDF in both 1997 and 1998 (Appendix 12, Table 5). Results of this cutting study clearly indicate that the third cutting interval (6 weeks) is too long to insure acceptable quality. A 5-week cutting interval or less depending on forage yield is recommended. Delaying harvest until later in spring may also adversely impact forage quality of the second cutting, though this is dependent on climate.

Invitro digestion kinetics
Interactions between initial cutting dates and second cutting dates were not significant (P > 0.05) for potentially digestible fiber (Do), indigestible fiber (I), and rate of fiber digestion (k) (Appendix 12, Table7). Gamagrass cut at the 6-wk cutting interval had lower Do (48.2 ± 1.7% vs 50.5 ± 0.6% and 50.3 ± 0.6% vs 55.3 ± 1.5% for 1997 6- vs 4-wk and 1998 6- vs 4-wk, respectively) and higher I (23.0 ±2.5% vs 20.2 ± 1.7% and 21.7 ± 2.2% vs 17.7 ± 2.2% for 1997 6- vs 4-wk and 1998 6- vs 4-wk, respectively) than the 4-wk cutting interval, regardless of initial harvest date. This was generally true for k as well. Forage quality and digestion kinetics of gamagrass harvested at 5-wk cutting intervals tended to be intermediate between 4- and 6-wk cutting intervals. See Appendix 12, Table 8 for a summary of the data.

Variety study
There were significant differences between the genotypes for vegetative tillers for all variables measured except for ADF in 1997 and for NDF and Lignin in 1998 (Appendix 12, Table 6). For reproductive tillers only lignin in 1998 was not significantly different. Later harvest date resulted in higher (P < 0.05) NDF, ADF, and lignin as might be expected. In vitro digestibility, dNDF, and crude protein generally declined with advancing harvest date in 1997 and 1998. There appears to be little difference in forage quality between reproductive and vegetative tillers when cut at the appropriate time. There are only minor differences between their means with high forage quality indicator values switching between tiller types between years for some of the variables measured.

IV. Conduct on farm feeding trials comparing eastern gamagrass as a significant portion of a dairy ration

Dry matter intake was lower for cows consuming gamagrass in the CU trial, but milk production did not differ between the diets. In the SUNY-Cobleskill trial, there were no differences in dry matter intake, milk production, or milk composition. Results from this study indicate that gamagrass can be used to replace the fiber coming from corn silage. This will result in considerably more grain being brought from off farm. Whether or not this is economically feasible will depend on the price of grain. Nutrient management aspects of possibly increasing feeds brought from off farm need to be considered. A more detailed account of the materials and methods and results are found in Appendix 13. A breakdown of the costs of the rations in the study is found in Appendix 13.

Appendix 1

A change made in the original work plan to increase the area of farms participating in the project from just Montgomery and Herkimer counties in NY. Also included was SUNY Morrisville and Cobleskill Ag. & Tech. and the Cornell T & R Center. The inclusion of these institutions gave us the opportunity for more controlled feeding trials. A change was made to conduct the animal feeding trials at these locations instead of on farms so that reliable data could be obtained that later could be used by all farmers.

Participation Summary

Education

Educational approach:
Outreach and dissemination

In summary, out reach and dissemination has been accomplished by tours at participating research facilities, tours at participating farms and at the Big Flats Plant Materials Center (PMC). Posters which included information about the project was displayed at farm shows. Gamagrass hay was displayed at two county fairs. An article was written by a Syracuse, NY newspaper with a photo about the project. Articles have been written for the USDA-NRCS Plant Materials Program newsletter which, is distributed to all of the NRCS and SWCD offices in the Northeast. A NRCS Newsletter with 5 issues on eastern gamagrass was written with contributions from University and ARS personnel. Research was published in the Annual Technical Report of the Big Flats PMC that goes to many researchers and agency personnel. Oral and Poster presentations were given at professional meetings, which included many extension personnel from the Northeast. A manuscript was written and published in the proceedings for the 2nd Eastern Native Grass Conference in Baltimore Maryland. A talk was given at the Stueben County Grazing Conference. Assisted in the production of two videos on eastern gamagrass. A more detailed accounting of these outreach activities is given in Appendix 2 & 3.

A newspaper article was written about the project in the Syracuse Post Standard. 1998.

Two farm field days were held at SUNY Morrisville Agriculture and Technology College in September of 1997 and 1998 with Wagon Tours that included about 100 farmers each year.

An Extension Tour visited the Len Bauer SARE Project site in Sullivan County, July 1998, with about 20 farmers.

An oral presentation was given at the USDA ARS Beltsville Station on the project to ARS scientists and NRCS Grazingland Specialists, Sept 1998.

Mohawk Valley Sustainable Agriculture Network, March 1999 meeting, update on project to members, 12 farmers in attendance.

A poster presentation “ Eastern gamagrass forage quality as influenced by harvest management” was presented at the American Society of Agronomy’s annual meeting in Salt Lake City, Utah 10/31-11/4/99.

A manuscript “ Eastern gamagrass forage quality as influenced by harvest management” was published in the proceedings of the 2nd Eastern Native Grass Conference held 11/17-19/99 in Baltimore, Maryland.

In 1999, a poster from SUNY Morrisville which included describing the project was displayed at Empire Farm Days, at the Central NY Farm Progress Days, and at the New York State Fair.

Managing Nutrients and Pathogens from Animal Agriculture Conference, held in Camp Hill, Pa. On March 28-30, 2000. A poster was presented on “Eastern Gamagrass Forage Quality as Influenced by Harvest Management”. There were 329 people in attendance.

Steuben County Grazing Conference was held in Kanona, NY on March 21, 2000. The conference was sponsored by Grazing Lands Conservation Initiative of New York, Cornell Cooperative Extension, Steuben County SWCD and Sullivan Trail Resource Conservation and Development (RC&D) Project. A slide presentation on eastern gamagrass was given, 60 people were in attendance.

The 17th annual Farm Diversity Conference 2000 was held in Norwich New York on April 1, 2000. The South Central New York RC&D hosted the conference. The Keynote speaker was Allan Savory, discussing Holistic Management. A poster was presented on the eastern gamagrass SARE project. 220 people were in attendance.

July Field Days for Crop Producers, “ Forage Crop Alternatives” Cornell Cooperative Extension hosted these programs in cooperation with SUNY Cobleskill Farm and the NRCS Big Flats Plant Materials Center. July 6, 2000 at SUNY Cobleskill farm tour of gamagrass field plots 15 people in attendance.

July Field Cornell and Chenango Co. Cooperative Extension hosted the work shop which included a stop at Peter Lathrop’s farm in Sherburne, NY to tour the gamagrass field plots 11 people were in attendance.

A poster “Yield of Eastern Gamagrass with Interseeded Legumes” was presented at the American Society of Agronomy meeting in Minneapolis MN., on 11/5-9/00.

Field Day at Big Flats Plant Materials Center in Big Flats, NY which included a tour of SARE gamagrass plots 7/17, 7/20, 9/13/00, a total of 106 people attended.

Eastern gamagrass hay from the SARE grant was displayed at county fairs in Chenango and Washington counties in NY in 8/99 and 8/00. This generated some interaction among producers inquiring about eastern gamagrass.

Newsletters: Eastern gamagrass SARE project activities was distributed in the Mid-Atlantic IRT, USDA-NRCS Technical Update #4 & #5 Eastern Gamagrass for Forage, soil Improvement, and Buffer Strips distributed to NRCS and SWCD offices in the mid –Atlantic region. Plants NE a Plant Materials newsletter distributed to all NRCS and SWCD Field offices in the NE.

Project Outcomes

Impacts of Results/Outcomes

The impact of this work is that we determined that eastern gamagrass has good forage quality to feed to Dairy cows. That eastern gamagrass has better forage quality when grown in the Northeast compared to the South and Midwest and that when fed to Dairy cows milk production can be maintained at current levels. The economics will depend on grain pricing since concentrate levels were increased in the gamagrass diet. At current pricing the gamagrass ration cost less or equal to the corn silage rations used in our study. We pushed the limit of the amount of gamagrass in a ration so if used it at a reduced rate the amount of grain needed in the diet would be reduced. The practice of interseeding legumes with eastern gamagrass did not prove to be a practical option. Perhaps seeding later in its second year may work. Weed competition is a very big problem with eastern gamagrass. Weed control needs to be solved before eastern gamagrass can be successfully used. Several non-herbicide suggestions were mentioned in the section, “Areas needing further study”. As a result of the dry and cold seasons encountered during the study the eastern gamagrass did not perform as well as expected despite excellent stand establishment. Competition from weeds was more severe due to the reduced gamagrass growth. The use of very large farm equipment especially when soil conditions were wet caused excessive damage to the gamagrass, this was not as big a problem when average sized farm equipment was used. Fifteen farms/research facilities established eastern gamagrass, the next season will be important to observe how the eastern gamagrass compete with the weeds after an additional year of harvest. We will be monitoring yields to observe growth in a year which hopefully will represent average conditions.

• Eastern gamagrass yields are negatively effected by perennial companion crops especially white clover, red clover and alfalfa reducing gamagrass yields by 69.7%, 86.7% and 71.3% respectively.

• Companion crops can be successfully interseeded into eastern gamagrass to reduce erosion and to add a legume component to the stand.

• On drier sites and on drier years companion plantings are more competitive on the gamagrass.

• The cool season legumes get a 4-6 week start on the gamagrass in the Spring reducing the yield of the first cutting of gamagrass.

• Companion plantings increased overall yields, reduced weeds but competed with the gamagrass.

• Birdsfoot trefoil was the least competitive perennial legume.

• Legumes eventually allow perennial and annual weeds to invade reducing the quality of the stand.

• Oats can be interseeded after the gamagrass is established as a cover crop for the 1st year to reduce erosion and to possibly reduce frost heaving.

• Eastern gamagrass yield was negatively effected by the cool growing season allowing for increased competition from the cool season companion crops.

Economic Analysis

Eastern gamagrass being a long lived perennial requires establishment only once in a 10 year or more cycle. Eastern gamagrass requires low inputs in lime and P & K fertilizer but does respond to nitrogen fertilizer. Weed control is an issue during establishment and may be a maintenance problem. A cost associated with the 2nd year was an early clipping for weed control which is a reason the cost of machinery operations between the second and third year is not that different This is a cost not associated with the establishment of cool season grasses but may be less than in an annual crop such as corn silage. Nitrogen fertilizer is not applied during the establishment year since the gamagrass establishes slowly and the weeds would take advantage of the fertilizer. The second year 75 lbs/ac of nitrogen is applied and subsequently 150 lbs/ac is applied.
We analyzed eastern gamagrass establishment costs and spread that cost over a 10 year period. We assumed no yield the first year, a single cut of low value hay, $80/ton, the second year at 3 t/ac, and two cuts of good quality hay the third and subsequent years at 3.5 t/ac. In some years there may be a third cutting, not considered here. We based the value of the forage on market values of $80, $100 and $120 and per forage value using the ‘FeedVal’ program and forage quality %CP, ADF, NDF, TDN, Ca, and Phosphorus of 16.0, 35.6, 66.0, 64.0, 0.5 and 0.3% respectively. The quality data used in this analysis was not an average from the forage quality study reported on in this report, which had uncharacteristically high NDF. The values were based on several years of forage quality testing.
The results of the analysis found a total cost of establishment of $264.88, with no returns the 1st year due to no harvest. The returns over total costs in year two with a 3 t/ac yield, was $59.52/ac assuming a low value for the hay of $80/ton or $119.52 /ac assuming $100/ton hay, with a total cost/ton for year two of $60.16. In year three and beyond the forage value over total cost was $141.74/ac with a return over total cost of $131.24/ac for $100/ton hay and $201.24/ac for $120/ton hay. The total cost per ton in year three and beyond was $62.50. The cost of establishment was spread over 10 years. The costs per ton are high due to not obtaining a cut the establishment year. The spread sheet analysis and sources of inputs for the analysis is found in appendix 4.
A spread sheet was created for corn silage yielding 15 t/ac, the state average, with returns over total cost of $55.93/ac with a total cost/ton of $21.27, based of a price per ton of $25.00. Alfalfa costs and returns for a yield of 3 tons/ac at $130/ton had a return over total cost of $130.21/ac with a total cost/ton of $86.60. Another analysis for alfalfa at 3.5 tons/ac for a 5 year stand at $120/ton yielded an annual net return/ac of $133.05 with a cost of $62.39/year. It seems that gamagrass, assuming a stand lasting 10 years, with 3.5 ton/ac after the 2nd year, is in line with other forages grown in New York.

Areas needing additional study

Areas Needing Further Study

Further study in evaluating narrower row spacings (10-24 inches) of eastern gamagrass is warranted to improve yields in the NE and to help compete against weeds. The establishment of switchgrass along with eastern gamagrass may improve yields and help with controlling weeds and erosion while maintaining current row spacings (30-36 inches). The establishment of eastern gamagrass as a fall dormant seeding under a winter rye or wheat crop would allow for a harvest as well as supplying some weed and erosion control during the establishment year. The interseeding of cereal rye into the gamagrass during the establishment year in August would provide erosion control in the fall and spring and weed control and an additional harvest the second year. The allelopathy and competition of cereal rye on eastern gamagrass needs to be studied in relation to these two systems. The establishment of legumes frost seeded into a mature gamagrass stand is needed to observe if the competition of the legumes would be as severe as when the legumes were interseeded into a new stand. One of the biggest challenges to establishing eastern gamagrass is weed control. It is well known that eastern gamagrass is tolerant to many herbicides registered for corn. The use of herbicides would solve the weed problem for conventional farmers.

References

Evers, G.W. 1985. Forage and nitrogen contributions of arrowleaf and subtyerranean clovers overseeded on bermudagrass and bahiagrass Agron. J. 77:960-963.

Gettle R.M. 1996. Frost-seeded legumes into established switchgrass: forage yield and botanical composition of the stratified canopy. Agron. J. 88:555-560.

Marten, G.C. 1989. Summary of the trilateral workshop on persistence of forage legumes. P. 569-572. In G.C. Marten et al. (ed.) Persistence fo forage legumes. Proc. Trilateral Workshop, Honolulu Hawaii. 18-22 July 1988. ASA, CSSA, and SSSA, Madison, WI.

Posler, G.L., and A.W. Lenssen, and G.L. Fine 1993. Forage yield, quality, compatibvility, and persistence of warm-season grass-legume mixtures. Agron J. 85:554-560.

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.