Sweet Corn
Sweet corn, also called indian corn, sweetcorn, sugar corn, pole corn, or simply corn, is a variety of maize with a high sugar content. Sweet corn is the result of a naturally-occurring recessive mutation in the genes which control conversion of sugar to starch inside the endosperm of the corn kernel. Unlike field corn varieties, which are harvested when the kernels are dry and fully mature (dent stage), sweet corn is picked when immature (milk stage) and eaten as a vegetable, rather than a grain. Since the process of maturation involves converting sugar into starch, sweet corn stores poorly and must be eaten fresh, canned, or frozen before the kernels become tough and starchy.
Growing sweet corn: Soil pH: 6pH to 6.5pH Sun: Full Sun Tilling Depth: 10 inches Planting Depth: 1 inch deep Planting pattern: Use a block pattern, 3 to 4 short rows side by side Fertilize: 12" in height, for tall varieties, 18" - 24" high Harvest: 64 days Seedlings emerge: 7-14 days.
For the beginner who only has space for one variety, Early Sunglow is a good choice. If you have space for two blocks of corn, go with Early Sunglow and Golden Cross Bantam, or just make a second planting of Early Sunglow 15 to 30 days after the first. These varieties are among the hardiest and easiest to grow, and seed racks in local department or hardware stores are likely to have them. Once you have successfully grown corn, in future years try other varieties in the se, sh2 and sy types. These may need to be planted a couple weeks later for sufficient warmth and have somewhat lower germination rates. Don't be afraid to try white and bicolor too. Just be sure to isolate supersweet varieties (sh2 or augmented sh2) from other corn by either more than 100 ft(33 m) or more than 15 days in maturity time.
Bt corn (Transgenic maize) resists certain insects and commercial growers have access to sweet corn seed bred with this artificial trait. Bt corn and other transgenic varieties are not available to the home grower due protocols that must be followed in their production.
Water Pollution
Water pollution is the contamination of water bodies such as lakes, rivers, oceans, and groundwater caused by human activities, which can be harmful to organisms and plants that live in these water bodies. It occurs when pollutants are discharged directly into water bodies without treating it first.
Water pollution is a major problem in the global context. It has been suggested that it is the leading worldwide cause of deaths and diseases, and that it accounts for the deaths of more than 14,000 people daily. In addition to the acute problems of water pollution in developing countries, industrialized countries continue to struggle with pollution problems as well. In the most recent national report on water quality in the United States, 45 percent of assessed stream miles, 47 percent of assessed lake acres, and 32 percent of assessed bay and estuarine square miles were classified as polluted.
Water is typically referred to as polluted when it is impaired by anthropogenic contaminants and either does not support a human use, like serving as drinking water, and/or undergoes a marked shift in its ability to support its constituent biotic communities, such as fish. Natural phenomena such as volcanoes, algae blooms, storms, and earthquakes also cause major changes in water quality and the ecological status of water. Water pollution has many causes and characteristics.
The specific contaminants leading to pollution in water include a wide spectrum of chemicals, pathogens, and physical or sensory changes such as elevated temperature and discoloration. While many of the chemicals and substances that are regulated may be naturally occurring (calcium, sodium, iron, manganese, etc.) the concentration is often the key in determining what is a natural component of water, and what is a contaminant.
Oxygen-depleting substances may be natural materials, such as plant matter (e.g. leaves and grass) as well as man-made chemicals. Other natural and anthropogenic substances may cause turbidity (cloudiness) which blocks light and disrupts plant growth, and clogs the gills of some fish species.
Many of the chemical substances are toxic. Pathogens can produce waterborne diseases in either human or animal hosts. Alteration of water's physical chemistry include acidity (change in pH), electrical conductivity, temperature, and eutrophication. Eutrophication is the fertilization of surface water by nutrients that were previously scarce.
For more information (background, pictures, experiments and references): Water Pollution
Source: Wikipedia (All text is available under the terms of the Creative Commons Attribution-ShareAlike License)
|