Ancient Tree Flowers

first_imgSurrounded by trees, it’s easy to overlook their value. It’s also easy to ignore theirgreat biological history. But deep in the past, the story of trees contains many lessons. The wind was left behind in the forest top, along with the many wind-pollinatedflowers of other tree species. Long ago on a continent far away was a warm, humid forest. In it were many kinds ofplants, each locked into fierce competition to collect and control resources. Thesuccessful ones could grow, defend themselves and reproduce. Only successful plantssurvived. The showy tree flowers we see today are from this lineage. Their bright colors are astop sign for animals to explore, maybe receive a treat — and fertilize the tree bycarrying pollen. To succeed, a tree had to reproduce. One successful reproduction system was “conebearing.” Early in tree history, many forms of spirally designed cones were producedon branches and along trunks for seed production. These trees also produced small, fragile cones that held pollen. When these conesmature, they rupture and release millions of pollen grains. For creatures that use sight and smell, tree flowers can be great attractants and anecessity. Trees have come a long way from a simple, small, magnolia-like flower inthe bottom of a forest to the widely diverse tree-borne flowers we see outside ourwindows. Large, woody cones held seeds where the tree could nourish the embryos, and wherethe wind could catch seed edges and wings for distribution across the forest. Georgia’s trees tell many stories of success and failure, an ecological heritage that hassheltered humans from climate and poverty. One day among the dinosaurs, a genetic experiment was set up. A small tree, growingbeneath much larger and taller brethren, generated a flower. It wasn’t derived, as coneswere, from woody twigs but from modified leaves.center_img Warm, sunny days with low relative humidity help release pollen. The air around thesmall cones buoyed up the pollen as the wind swirled it around the canopy tops. The forests, savannahs and prairies of Earth are covered with wind-borne pollenproducers. From some perspectives, showy flowers are relics of a genetic experimentthat failed. People have been able to extract great value from these showy-floweredspecies. This tree flower was designed not for the wind, but to attract insects, birds and smallmammals. Only those trees whose crowns were up in the wind could distribute pollen and seedssuccessfully to new sites. Young trees had to survive for years beneath taller light- andwind-blocking trees for their place in the sun. Across the plant kingdom, the showy flowers have been successful in many places. Butthe miniaturized wind-pollinated flowers have become even more successful. In this experiment, all the tree traits (and all the resources required for these traits)needed to use wind power for reproduction could now be used instead to induceanimals to move pollen. This required new parts and designs. Trees generated newcolors, shapes and smells as enticements. For little trees, the dungeons or understories of these forests were hard to escape beforecompetition and pests eliminated them. The spring you see and smell had its roots in an ancient forest.last_img

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