Neochetinia eichhorniae causes "a substantial reduction in water hyacinth production" (in Louisiana); it reduces plant height, weight, root length, and makes the plant produce fewer daughter plants. Neochetinia eichhorniae was imported from Argentina to Florida in 1972.
Fresh plants contain prickly crystals. This plant is reported to contain HCN, alkaloid, and triterpenoid, and may induce itching. Plants sprayed with 2,4-D may accumulate lethal doses of nitrates, as well as various other nocive elements in polluted environments. See further down.
Wolverton and McDonald report only 0.2 m3 methane 7 per kg, indicating requirements of 350 MT biomass/ha to attain the 70,000 m3 yield projected by the National Academy of Sciences (Washington). Ueki and Kobayashi mention more than 200 MT/ha/yr. Reddy and Tucker got an experimental maximum of more than a half ton a day. Bengali farmers collect and pile up these plants to dry at the onset of the cold season; they then use the dry water hyacinths as fuel. They then use the ashes as fertilizer. In India, a ton of dried water hyacinth yield circa 50 liters ethanol and 200 kg residual fiber (7,700 Btu). Bacterial fermentation of one ton yields 26,500 cu ft gas (600 Btu) with 51.6% methane, 25.4% hydrogen, 22.1% , and 1.2% oxygen. Gasification of one ton dry matter by air and steam at high temperatures (800°) gives circa 40,000 ft3 (circa 1,100 m3) natural gas (143 Btu/cu ft?) containing 16.6% H3, 4.8% methane, 21.7% CO, 4.1% , and 52.8% N. The high moisture content of water hyacinth, adding so much to handling costs, tends to limit commercial ventures., A continuous, hydraulic production system could be designed, which would provide a better utilization of capital investments than in conventional agriculture, which is essentially a batch operation.,
The labour involved in harvesting water hyacinth can be greatly reduced by locating collection sites and processors on impoundments that take advantage of prevailing winds. Wastewater treatment systems could also favourably be added to this operation. The harvested biomass would then be converted to ethanol, natural gas, hydrogen and / or gaseous nitrogen, and fertilizer. The byproduct of water and fertilizer can both be used to irrigate nearby cropland.roots of Eichhornia crassipes naturally absorb pollutants, including lead, mercury, and strontium 90, as well as some organic compounds believed to be carcinogenic, in concentrations 10,000 times that in the surrounding water. Water hyacinths can be cultivated for waste water treatment.