Potential Grasses as Alternative Forage Crops for the Virgin Islands

Commodities

• Agronomic: grass (misc. annual), hay
• Animals: bovine, goats, sheep

Practices

• Animal Production: feed/forage, grazing management
• Crop Production: cover crops

The project will introduce to the sheep, goat/cattle producers new alternative crops that provide hay and grazing options along with specific recommendations for their best management practices. The leguminous cover crop will improve the soil quality for sustainable production of forage crops. The project will enhance the awareness, introduction, and effectiveness of increasing availability of forages and reduce input. The two participated producers and other growers will have increased awareness and knowledge about the applicability and compatibility of alternative crops and cover crops to adopt.

The year-round little fluctuation of temperature, with no frost condition in the Virgin Islands allows farmers to effectively plant teff and Rhodes grasses for extended period and complement with legume crop that potentially increase availability of quality hay or pastures by suppling protein during the dry season. The introduction of drought tolerant, low input alternative grass crops in conjunction with leguminous cover crops can lead to a range of soil health benefits: improved agricultural productivity, greater drought resilience, sustainable grazing systems, and better environmental outcomes. The project is designed to develop integration of livestock production systems with improved alternative forage and cover crops that are economically profitable, environmentally sound, socially acceptable, technically feasible, and biologically efficient.

Teff, Eragrostis teff, is a warm season, C4-photosynthesis annual grass that originated in East Africa where it was utilized mainly as a stable grain crop and its stubble and straw as animal feed or for construction purposes (Burayu et al.2006). It is relatively a new crop to the US, imported as an alternative grain source and as gluten free flour source for the population suffering from Celiac’s Disease (Gluten Intolerance). Over the last ten years, it is gaining popularity in the U.S. as high-quality summer forage, fodder, and grain crop (Hunter et al., 2007; Twidwell et al., 2002). It has gained momentum as a forage crop in USA and improved types have been developed and commercialized.

There are several reasons for growing teff and Rhodes in US Virgin Islands as alternative crops. Teff is a self-pollinated, warm season annual grass, which can be harvested multiple times during the growing season as dry hay, silage, or pasture. As a fast-growing crop, teff combines excellent forage quality with high yield during a relatively short growing season and drought tolerant crop. After the first cutting, it can also be used for pasture within a good rotation. This makes it a great option for livestock and hay producers. The main benefit of teff as forage crop is that it is fast growing, most productive during hot weather and can provide badly needed forage during times of water deficit (Stallknecht et al., 1993). Incorporating warm- season annual forages into a grazing system is another way producer reduce the risk of low forage supply, and this add up the benefit of teff. Teff gives reasonable yield when other cereals yield is depressed significantly in low or excessive moisture conditions (Hunter et al., 2007). It can be grazed to cattle/horses or alternatively harvested for hay. The crop grows well in a water logging condition when precipitation is high; it is drought tolerant on the other sides. Teff is generally low input crop. It requires a modest amount of fertilizer contributing to reduced chemical use. Few insect and disease problems have been reported in this crop even in its native land, East Africa. Preliminary University and grower trials in different States of US have demonstrated that Teff can be grown, in most locations, without insecticides or fungicides. Public and Private researchers in the last five years have identified several superior forages producing varieties. Teff established fast in emergence (3-5 days) and covering per unit area (in a week) as compared to many native grasses grown in South USA. The main advantages of these new non-grain types of Teff are their ability to produce high yields and high quality in the summer months in contrast to many crops.

Rhodes grass (Chloris gayana) is native to Africa, but it can be found throughout the tropical and subtropical world as a naturalized species. Rhodes grass is important as permanent pasture or a short- to medium-term pasture ley. It makes good hay if cut at proper time and provides better stand than buffel grass, one of the dominant pasture grasses in south shore and east of St. Croix, VI. It is widely adapted, easily established, very drought tolerant, salt-tolerant and tolerates heavy grazing. It is usually grown in areas receiving an average annual rainfall of 30-45 inches. Hay production is the most common use for Teff and rhodes. In years of adequate rainfall, three to five harvests can be completed in the growing season. Due to the fine texture of the stems, Teff grass dries faster than other annuals and should be baled at 20 percent moisture for square bales and 18 percent for round bales. Grazing can be done successfully by multiple species.

Climatologically, Virgin Islands (St. Croix) has ideal condition for teff and Rhodes production. Temperature wise teff and Rhodes can be seeded each month. There is no frost time, as teff is sensitive to frost. Average seasonal temperature is 79, 80, 84, 82 inches in winter, spring, summer and fall respectively. The total annual rainfall (about 40 inches average annual) is enough to grow teff and Rhodes. St. Croix usually experiences 2.44, 2.43, 2.92 and 5.64 inches of average seasonal rainfall in winter, spring, summer and fall, respectively. Therefore, it is conducive to grow teff and Rhodes fast and sustainably.

The advantages of cover crops are well documented in many literatures. Cover crop such as Fava bean, cowpea, or lablab as an integral component of crop/livestock production has immediate economic value to the farmer that come from incorporating ruminant livestock into the crop production system. In addition, the integration of improved grazing and forage systems with beef cattle or sheep and goat can reduce fertilizer needs.

Two years on-farm replicated trials will be conducted at two sheep/goat and cattle producing farmer’s sites in 2022 and 2023. We chose two farms as the specific sites to conduct the on-farm research taking them as a representative small ruminant and cattle farms. The two farms are in one of the four U.S. Virgin Islands at St. Croix, VI. The on-farm trial at east side is relatively dry and drought prone area with less grass vegetation cover. Buffel grass (Cenchrus ciliaris) and hurricane grass are more commonly used as grazing grass. The west side is, relatively wet and with more grass coverage.  Guinea grass and hurricane grass are mainly used as grazing grasses. The farmers at St. Croix have produced a mix of beef, sheep, and goat.

Two introduced grasses (Teff and Rhodes) and one commonly grown grass (Mombasa grass) will be seeded into conventionally prepared land with a grass seed drill at 8-10 lb./acre in June 2022 (Summer experiment) and each will be evaluated on 0.25 acres for their establishment, height, and yield characteristics, forage yields and nutritional value under rain fed conditions. The plot will be more divided in to fertilized (0.125 acre) and unfertilized (0.125-acre) plots. The replica of this experiment will be repeated in October 2022 (fall experiment). Spilt plot Design, species as a main plot (3), nitrogen as sub plots (2) with three replications will be employed. The hypothesis to be determined is that better grasses that give good germination, emergence and establishment, and higher yields and nutritive value in rain fed agriculture will be identified. We collect data on emergence percentage, coverage, height and yields and forage quality. Different time of planting means, differences in water availability to plants. Thus, we will assess the relative drought tolerance of these three grasses that vary in their ability to withstand prolonged periods of drought and gives reasonable yields. The forage yield of species will be determined at least three times in the season to estimate forage availability. Forage yield will be determined approximately 40-50 days after planting, and 30-40 days after cutting. After first cutting of grasses, we will allow sheep, goat, or cattle to graze on the grasses, and assess their preference. Will determine grasses rate of recovery after grazing. The remaining 0.25 acres will be used for leguminous cover crop, and under plowed 2-3 months after planting. In the second year (2023), grasses will be sown on previously under plowed leguminous plots and plots without leguminous plots. Spilt plot Design, species as a main plot (3), cover crops as sub plots (2) with three replications will be employed to evaluate the performance of grasses in their growth, yield, and quality. The abovementioned procedures in year one will be repeated following the first cutting of grasses. In both years, the soil samples will be collected before sowing the leguminous crops and after termination and standard soil samples analysis will be made following the established procedures. Plant samples will be taken from all plots and tissue analysis will be done. The forage quality will be assessed by determining Crude Protein (CP, %), Neutral Detergent Fiber (NDF, %), Acid Detergent Fiber (ADF, %), Total Digestible nutrients, and Relative Forage Quality (RFQ).

One aspect of sustainable agriculture is economic profitability of a new intervention. The economic aspect will be evaluated to gauge the economic benefits of the introduction and adoption of alternative crops as an alternative crop in USVI. We will collect information including crops grown, farm size, land tenure characteristics, and typical machinery complements. We will also evaluate costs of production, including chemical, fuel, and fertilizer. Finally, alternative production crops and activities will be designed for the limited-resource farm.

Statistical Analysis. The response variables for all experiments will be analyzed by using JMP ver.13 SAS Statistical software.