Scientists have found that the 24-hour circadian rhythms that guide animal behavior also exist in plants. Research at the Agricultural Research Service's Vegetable Laboratory shows that a biological clock located in the nuclei of plant cells goes off every morning to prepare plants for their various activities, according to an ARS Web site article by David Elstein.

ARS plant physiologist Autar K. Mattoo has found a few reasons why these clocks go off at precise times and has studied a specific enzyme that modifies the protein known as D1, a critical element in the photosynthesis process, the Web site article says.

Binding phosphorous to D1 at a specific threshold provides a plant with a biotiming signal that tells it to adjust its metabolism to face the onset of the day's brightest light. The plant also puts on “sunscreen” to protect itself from ultraviolet-B radiation damage, according to the article. Experiments have found that this biological clock almost always goes off a few hours before noon. Mattoo and fellow researchers and students were the first scientists to determine the whole life cycle of the D1 protein after 22 years of collaborative research. For more information, visit


Lawns around the country are turning green with envy as Briggs & Stratton Corp. announces the 2003 National Top 10 Lawns with a View. Central Park's Great Lawn in New York City claimed the top spot in the annual ranking compiled by the small engine manufacturer, state tourism officials and lawn experts.

Since 1998, Briggs & Stratton has honored impressive public lawns around the country. This year, the Milwaukee-based company is honoring beautiful green spaces located in, or overlooking, impressive scenery. The 2003 Top 10 national winners, which can be found at, were chosen from regional winners in the East, West, South and Midwest. The 2003 national Top 10 Lawns with a View include:

  • Central Park's Great Lawn — New York

  • Nelson-Atkins Museum of Art — Kansas City, Mo.

  • Piedmont Park — Atlanta

  • Minneapolis Sculpture Garden — Minneapolis

  • International Peace Garden — Dunseith, N. D.

  • Bicentennial Mall State Park — Nashville, Tenn.

  • Bascom Hill — Madison, Wis.

  • Esplanade — Boston

  • Washington Park — Portland, Ore.

  • Pebble Beach Golf Links — Pebble Beach, Calif.

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