Bridging the Fall Forage Gap with Stockpiled Limpograss Along the Southern Gulf Coast

View the project final report

Commodities

• Agronomic: grass (misc. perennial)
• Animals: bovine

Practices

• Animal Production: feed/forage, grazing management

Stockpiling limpograss is the proposed solution to reduce the forage shortage in the Fall. Grazing stockpiled limpograss is also more sustainable than conserved forages such as hay or baleage. These conserved feedstuffs require greater use of inputs, including machinery, fossil fuel, and fertilizers. Limpograss has unique characteristics including a slow decrease on its digestibility compared with other warm-season perennial grass, being a perfect candidate for stockpiling. Limpograss is less light sensitive compared with other warm-season perennial grasses such as bahiagrass (Paspalum notatum Flügge) or bermudagrass [Cynodon dactylon (L.) Pers.]. As a result, if there are warmer periods within the cool season, limpograss starts greening up, enhancing forage nutritive value. Limpograss can also help to bridge the Spring gap, when bahiagrass and bermudagrass are still dormant. Limpograss is one of the warm-season perennial grasses that have the earliest growth in the Spring. Therefore, establishing limpograss along the Gulf Coast can extend the grazing season and reduce off-farm inputs, increasing sustainability of beef farm operations.

Because lack of planting material and lack of knowledge on how to manage limpograss along FL Panhandle is one important ‘bottleneck’ for adoption, we propose to establish Gibtuck limpograss on three producer’s sites along the FL Panhandle and perform management trials at each location. This will disseminate planting material across different locations along the region and increase adoption. Once the limpograss is established, we will execute on-farm small plot trials assessing limpograss growth and nutritive value using different stockpiling periods. This will generate information to manage limpograss along FL Panhandle as well as produce planting material for further multiplication.

Three producers strategically located along the FL Panhandle will participate in this project. Planting material of Gibtuck limpograss is available at UF IFAS NFREC in Marianna and will be used to establish producer’s field in this project. Each producer will provide 1-acre field to establish the limpograss. Prior to planting, we will collect soil samples from 0-16”and analyze for soil fertility and soil physics. Producers will prepare the soil prior to planting. Limpograss stolons will be harvested and planted in the same day, at a rate of 1,500 lb/acre. The planting material (stolons) will be spread along the prepared land, disked in, and rolled/cultipacked. Fertilizer will be applied following IFAS recommendation. Planting is planned to happen in May-June 2021.

After limpograss establishment, plots will be staged by late August to early September to start stockpiling periods. Harvested limpograss will be used as planting material according to producer’s needs. On the planted area, we will install a small-plot trial with different stockpiling periods (treatments): 30, 60, 90, 120 days. Each plot will measure 6 x 15 ft and will be replicated four times. Treatments will be allocated in a randomized complete block design. These three on-farm trials will generate information on herbage accumulation and nutritive value of stockpiled limpograss along these different deferment periods. The trial will be repeated in 2022.

The central portion of the plot will be harvested using a collecting flail mower. All forage in the harvested area will be weighed (fresh weight) and recorded. Subsamples will be collected for DM determination and for nutritive value. Subsamples will be weighed before and after drying at 131˚F for 48 h in an air-circulating dryer for DM (131˚F) determination. Samples will be milled to pass through a 2-mm mesh using a Wiley Mill (Model 4, Thomas-Wiley Laboratory Mill, Thomas Scientific). Samples will be analyzed for in vitro digestible organic matter (IVDOM) and crude protein (CP). The IVDOM will be determined using the protocol described by Moore and Mott (1974). Nitrogen concentration will be analyzed using the Dumas dry combustion method. Prior to analysis, samples will be ball milled in a Mixer Mill (MM 400, Retsch, Haan, Germany) at 25 Hz for 9 min. Ball-milled samples will be used to determine total N concentrations by dry combustion using an elemental analyzer (Vario Micro cube, Elementar, Germany). Total N concentration will be multiplied by 6.25 to calculate crude protein.

Data will be analyzed using the SAS statistical package and the proc mixed procedure. Stockpiling period and farm site will be considered fixed effect, and replication within each farm and years considered random effect. Least square means will be separated using the PDIFF procedure from SAS and significance declared at P < 0.05.