Invasive aquatic plants are a problem all of the world. In Florida, the Florida Fish and Wildlife Conservation Commission uses chemical herbicides as one of their primary methods to control the plants. Worldwide, researchers are looking at more productive ways to get rid of unwanted vegetation. In a variety of locations, projects are studying the use aquatic weeds as animal feed.
Water hyacinth originated in tropical South America. It was introduced to the United States in 1884 at an exposition in New Orleans. The story goes that a Florida visitor to the exposition returned home with water hyacinth and subsequently released them into the St. Johns River. The aquatic weed rapidly spread to other waterways in the state, clogging waterways and crowding out native vegetation.
In 2012, Larry Ward of Ward Farms in Maryland conducted a research project sponsored by Sustainable Agriculture Research and Education (SARE).
The Water Hyacinth Project explored the value of the water hyacinth as a livestock nutrition source by analyzing the quantity grown and its nutritional value. Mr. Ward’s farming operation consists of 55 acres of owned farm land and agreements for farming roughly 120 acres of hay fields in the area. The focus of this project was on the 55-acre home farm where small quantities of livestock including sheep, goats, or cattle depending on market fluctuations are raised.
Larry Ward was the owner and farmer in charge of the project. Richard Nottingham was the technical advisor. He is an ag agent at the University of Maryland Extension located at the University of Maryland Eastern Shore (UMES). As part of the project, Mr. Ward was videoed feeding hyacinths to various farm animals.
The project found that while some animals, like horses, showed no interest in eating water hyacinths, others, like chickens and pigs, immediately took to it.
“Pigs just lost their minds over it,” Mr. Ward commented. Goats would only eat the leaves. Chickens ate the whole plant. Chickens appeared to prefer the water hyacinths to their normal feed, and came running when the hyacinths were placed in their enclosure.
Vietnam study focused on livestock
(Here’s your word for the day: Ensile — to prepare and store fodder so as to induce conversion to silage.)
“Effect of Water Hyacinth Silage on Intake of Nutrient Digestibility in Cattle fed Rice Straw and Cottonseed Cake” was published in 2012 in the The Asian-Austrailian Journal of Animal Science. The study was based in Vietnam where rapid growth of livestock production has inspired researchers to find new sources of fodder. The study found ensilaged Water Hyacinth could be a viable alternative in ruminant diets.
(Second word of the day: Ruminant — an even-toed ungulate mammal that chews the cud regurgitated from its rumen. The ruminants comprise the cattle, sheep, antelopes, deer, giraffes, and their relatives.)
Studies from the Ministry of Ag. in Tanzania, An Giang University in Vietnam, CelAgrid in Cambodia, Cantho University in Vietnam and the FAO United Nations also verify water hyacinth’s usability as livestock feed.
The website survivalgardener.com states water hyacinth maeks an excellent supplement to chicken and duck feed.
Hydrilla is a submersed plant. It can grow to the surface and form dense mats. It may be found in all types of water bodies. According to the University of Florida Center for Aquatic and Invasive plants, hydrilla was probably brought to the Tampa and Miami areas of Florida as an aquarium plant in the late 1950s. By the 1970s, it was established throughout Florida.
In the water, manatees, turtles, some snails and crayfish eat hydrilla.
Biological controls used on hydrilla include Chinese grass carp and hydrilla weevils.
A 1978 study at the University of Florida tested the use of hydrilla silage as cattle feed.
“Hydrilla Silage Production, Composition and Acceptability,” by Larry O. Bangall, K.E. Dixon and J.F. Hentges Jr., states the hydrilla was pressed and ensiled.
Steers readily accepted hydrilla silage fermented with adequate levels of dried citrus pulp, ground shelled corn and propionic acid. Steers consumed all of the hydrilla silage offered to them,
The researchers concluded that cattle readily accepted well-preserved hydrilla silage, but not low quality hydrilla hay. “The vegetation must be dewatered and supplemented with fermentable carbohydrate to ensile satisfactorily,” the study states.