FEATURED in the Daisy Group – January 21 2012
November 9 2011
August 18 2011
February 4 2011
Sunflower Family (Asteraceae)
Sunflowers have a type of phototropic response called heliotropism (sun turning); the leaves and flower heads of young sunflowers follow the sun and their orientation therefore changes from east to west during the day. The movements become a circadian response and when plants are rotated 180 degrees, the old response pattern is still followed for a few days, with leaf orientation changing from west to east instead. The leaf and flower bud phototropism occurs while the leaf petioles and stems are still actively growing and once mature the movements stop. The movement occurs as the petioles bend or twist during the day and at night they unbend or untwist.
Taken: August 1 2010
Along Hwy. 6 towards Hamilton, Ontario