Evaluation and Maintenance of Sustainable Systems for Alfalfa Production and Marketing Strategies on Coastal Plain Soils

Evaluation and Maintenance of Sustainable Systems for Alfalfa Production and Marketing Strategies on Coastal Plain Soils

Summary

Research scientists with the Texas Agricultural Experiment Station at Overton have overcome many of the production problems that limited alfalfa growth on Coastal Plain soils. Research results indicate that alfalfa has the potential to be an excellent legume for warm-season production on Coastal Plain soils. The purpose of this on-farm research is to continue evaluation of the long-term sustainability of alfalfa production on four farm cooperators’ sites after the original SARE grant terminated in May of 2002. Two additional years of research on field-scale alfalfa production and demonstrations on these farm and ranch sites were needed to determine sustainability of alfalfa on Coastal Plain soils.

Four farmers and ranchers in East Texas cooperated with research and extension personnel at Overton, in a Southern Region SARE Project to demonstrate the sustainability of alfalfa production on 23.5 acres of Coastal Plain soils. Establishment costs ranged from $232 to $353 per acre, depending on the amount of limestone needed to adjust soil pH to 7.0. Yields of 12-percent moisture hay ranged from 3.6 to 4.5 tons per acre the first season and from 4.6 to 5.3 tons per acre the second year. Crude protein ranged from 19 to 26% depending on growth stage and time of harvest. These cooperators primarily use produced hay on the farm or ranch to grow replacement heifers and bulls, but for economic analysis, the produced hay was valued at $135 per ton. In the first season of alfalfa production, on-farm cooperators’ net income was projected to range from $169 to $288 per acre. Similar projections from yield data the second year were $239 to $352 net income per acre depending on management and timely harvesting. Stands of alfalfa on the farm cooperators’ sites remained productive after two production years.

Four-year total yield was highest on the Seven P ranch at 5 tons/acre/year for both varieties followed by Griffin at 4.35 tons, Taylor at 4.13 tons, and Riley averaged 3.54 tons/acre. Yield the last two years was slightly lower than second-year yields.

Results from alfalfa production evaluations on these four farms for an additional two years show continued net income up to $329/acre in year three and ranging from $200/acre to $318/acre in year four. Stand remaining after four years of production for Amerigraze 702 ranged from 47% on the Griffin Ranch to 76% on the Taylor Ranch. Stand density for GrazeKing was best on the Taylor Ranch at 64% after four years.

Objectives/Performance Targets

To continue evaluation of on-farm alfalfa production an additional two years in order to determine its long-term sustainability on Coastal Plain soils.

Farm and ranch cooperators continued production on these demonstration sites for an additional two years. Timely hay harvests were made approximately at the 10-percent bloom stage of growth depending upon rainfall and proper drying conditions. Yield estimates were clipped from meter-square quadrats by research cooperators and bale counts and average bale weights were provided by stakeholders.

Yield estimate samples were processed for chemical analysis to determine nutrient uptake by the alfalfa. At the second harvest each season, 6-in. depth soil samples were collected from each forage sample site for chemical analysis. The extension economist conducted the economic analysis for each farm and ranch cooperator site using actual input costs and published cost estimates for farm operations.

Sustainability of the alfalfa stand was determined from yield estimates and by making stand counts. Percent stand was estimated visually. Plant sample nutrient concentrations as well as plant nutrient levels and pH in soils were evaluated to determine sustainability of production practices and the environmental consequences of these practices.

The continued growth of alfalfa on the farm and ranch fields after two additional years of production and evaluation, and the acceptance of alfalfa as an alternative forage crop for production on Coastal Plain soils in East Texas will indicate the success of this on-farm sustainable alfalfa project.

Accomplishments/Milestones

Alfalfa hay yields for the third and fourth years of this extended SARE project indicated increased production for each of the first two harvests compared to later season harvests. Dry conditions limited production to four harvests on the Taylor and Seven P Ranches in 2002. Fourth harvest yields were low on these sites. Extensive grazing by whitetail deer eliminated the final harvest each of these two years on the Griffin ranch as alfalfa is an attractive forage for these animals during late summer when native browse usually is limiting. Deer continued to graze the alfalfa even during the period when acorns were plentiful in the forest. Food plots of alfalfa for deer have aroused interest among hunters in this region.

Four harvests were taken from the Griffin, Taylor, and Seven P ranches the fourth year and final season of our evaluation. The Riley ranch made five harvests the final year of this study. Hay yields on the Seven P ranch were greater in each of the last two years than were yields on the Griffin, Taylor, and Riley ranches.

Four-year total yield was highest on the Seven P ranch where the average was slightly less than 5 tons/acre/year for both varieties. Alfalfa yield on the Griffin ranch followed closely averaging 4.47 tons/acre for Amerigraze 702 and 4.22 tons/acre for GrazeKing. Yield on the Taylor ranch averaged 4.13 tons acre per year, while on the Riley ranch alfalfa hay yield averaged 3.54 tons per acre per year. When averaged over all sites and years, the four-year total hay yield for GrazeKing was 16.64 tons/acre and for Amerigraze 702 was 17.08 tons/acre.

After four years in production, the Amerigraze 702 variety consistently maintained a better stand than did GrazeKing. The percentage cover when alfalfa was nearing harvest time on the Taylor and Riley ranches and the percent of crowns touching a 300 foot tape at 20 foot intervals on the Seven P and Griffin Ranches indicated approximately 50%, or greater, average stand remaining for Amerigraze 702 with a range of 47% stand on the Griffin ranch to 76% on the Taylor Ranch. The percentage stand remaining for GrazeKing ranged from 13% on a wetter side of the field on the Griffin ranch to 64% on the Taylor Ranch. Amerigraze 702 has a dormancy rating of 7 and GrazeKing is a dormancy rating 5. Both varieties are well adapted to the northeast Texas region, and should do well on Coastal Plain soils.

The Seven P ranch continued to have the most dense and weed-free stand of alfalfa after four production seasons. This was primarily due to timely removal of the previous grass crop during the summer preceding alfalfa planting in fall. At locations where less than adequate termination of the grass was accomplished, bermudagrass invasion of the alfalfa stand during the second and following production seasons was a problem that could not be overcome by use of herbicides currently labeled for grass control in standing alfalfa. Other weeds that were difficult to control in alfalfa included dock and pigweed. Poast used at label rates for control of other broadleaf weeds in late winter did not control dock, and the pigweed emerged over an extended period.

The Bowie soil on the Taylor and Seven-P ranches is excellent for alfalfa production. The Kirvin soil on the Griffin ranch also produced good yields because the subsoil pH levels were well above 5.5 to 4-ft deep. Kirvin is a more highly leached soil than is the Trawick on the Riley ranch. The Trawick is a red, well-drained soil with higher clay content and base saturation than other soils in this study. The Trawick subsoil pH was marginal near 5.4 to 5.5. The soil on this site was adequate for good alfalfa production, but did not produce alfalfa as well as the Bowie and Kirvin soils. However, the lower yields at this site are primarily due to delays in harvesting and several extended grazing periods that limited the number of harvests, especially in the third year when only two yield estimates were made.

Impacts and Contributions/Outcomes

On-farm cooperator alfalfa sites are located in four counties. Multi-county tours were advertised and conducted annually to allow farm clientele to observe alfalfa and to hear presentations on alfalfa production, alfalfa nutritive value, economics, and marketing. Agronomic, economic, and environmental evaluations were prepared and published. Detailed instructions on site selection, preparation, planting, and production, and harvesting methods will be prepared and distributed as hard copy and placed on a web site for routine viewing by interested clientele. Published reports, news releases, and video materials that document response to treatments will be prepared and used at producer and other clientele meetings to educate extension agents and producers regarding alfalfa production. Farm and ranch cooperators will be asked to share and discuss their experiences in alfalfa production with farm and ranch neighbors and interested clientele at agriculture meetings.

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