The Nikon MicroscopyU confocal microscopy image gallery was created with a PCM-2000 confocal scanning system interfaced to a Nikon Eclipse E600 upright microscope. Images were recorded in successive z-axis serial sections with C-Imaging Systems software with excitation illumination provided by an argon-ion and/or a helium-neon laser.

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Alfalfa, or Medicago sativa, is a deep-rooted perennial native to the Mediterranean region near Iran but which also grows well in North America and Western Asia. Also called Lucerne, or Purple Medic, it looks very much like clover with a smooth, erect stem growing 2-3 feet tall, grayish-green feathery trifoliate leaves, and egg-shaped leaflets. It is tolerant of a wide range of climatic conditions and can be grown in cool, humid environments as well as irrigated arid regions.

Ancient Chinese doctors used alfalfa to increase appetite and to help poor digestion. Modern day herbalists promote it for detoxification believing that it can help relieve certain types of ulcers, reduce inflammation due to arthritis, treat high fevers, cleanse the liver and bloodstream and alleviate allergic reactions related to plants and grasses. There are few if any valid scientific studies to support these claims, however, it's proven as an excellent source of vitamins, minerals, fiber, proteins and fats and especially rich in the amino acid tryptophan, iron and vitamins A, D and K.

High vitamin and mineral content is one of the reasons alfalfa is popular among farmers and planted in over 25 million acres in the United States. When alfalfa is cut prior to bloom, it is low in fiber and high in energy, which makes it an ideal component in livestock feed for dairy cattle, horses, beef cattle, sheep and milking goats. It also has a very high yield potential branding it with the name, "Queen of Forage". Also, it plays an integral role in crop rotations because it improves tilth (soil structure) helps control weeds in subsequent crops and also can help reduce the risk of nitrate contamination of ground water supplies by extracting nitrate from the subsoil beneath the average rooting zone.

Alfalfa has a good yield, but it can be a costly crop to grow. Annual dollar loses due to pests and disease run in the hundreds of millions. The potato leafhopper is the most problematic insect, yellowing the foliage and stunting stems in the crops of the central and eastern regions of the US. More that 20 diseases are a serious problem for alfalfa including bacterial wilts, fungal leaf spots, viruses, and nematodes. Most of these can be managed with proper treatment and pesticides.