Multiple On-Farm Use of Aquatic Plants and Animals
Harvey Harman designed a project that utilizes existing ponds and water sources on his farm to grow aquatic plants and animals. Many farms already have ponds or water sources that are seldom utilized for growing cash crops. Many different aquatic plants have economic value as food for human consumption, animal fodder, and for sale as garden ornamentals. Furthermore, aquatic and bog plants are some of the best filters known for purifying water and they also recycle nutrients. This is increasingly important for farms that have animals or have nutrient leaching and runoff.
One result of the project is that Harvey was able to recycle runoff from animal pens through a series of filter beds, utilizing aquatic plants, to capture nutrients and cleanse the water. He has developed a duck/tilapia/aquatic plant system in which the ducks and tilapia eat the aquatic plants and fertilize the water and the aquatic plants. Because of strict regulations by the North Carolina Department of Environment and Natural Resources (NCDENR), he was not able to run domestic greywater along with run-off from animal pens. He has been working with the NCDENR to meet their regulations. Even though his SARE grant has ended, he is still working to get his domestic greywater system approved.
He has had the most success with water-loving plants for the ornamental market. He has taken cuttings from flowering plants and ornamental shrubs to sell for the cut flower market. Another advantage of this system is that many of these ornamentals can be harvested during the off season when there is extra time and a need for cash flow. He has had particular success with corkscrew willow, pussy willow and horsetail.
He has also had success with duck weed, about 20 percent protein by dry weight, as feed for his chickens and ducks. His animals also did well on water hyacinths although he does not know their nutrient value. He also found that his goats and sheep ate cattails when they could get to them. They also liked bamboo which stays green all year.
He presented posters of his duck/plant aquaculture system at a Carolina Farm Stewardship Conference and at the Ten Year SARE Event. He also receives about 200 visitors a year at his farm.