Middle spring

Just when we think winter is gone, the dogwoods hint at the brilliant white of the season past.  

Dogwood flowers have always been a watershed in the seasonal rhythm. Their bloom marks the transition from early wildflowers of the forest floor to the rise of green into the canopy when tree leaves emerge with conviction.  

The chalky white blossoms of dogwood are somewhat of a ruse.  For most plants big colorful structures surrounding the flower parts are indeed petals.  No so for dogwood.  The four showy white parts are the bracts that surrounded the true flowers since last fall.  The thick leathery bracts protected the tender flowers against cold and wind through the winter.  Now they fold back and expand to expose a cluster of much smaller flowers.  The true flowers of dogwood are small with tiny pale yellow-green petals that open days after the bracts are in full spread.  

The tiny flowers of dogwood are fertilized by native bees.  The insects are attracted when the the flowers emit a volatile chemical into the air.  The "fragrance" is for bees only as we are not able to detect traces of the attractant.  

Once fertilized the flowers ripen and in the fall brilliant scarlet berries attract larger creatures.  All summer the fruits are dull green blending into the surroundings.  Their camouflage keeps them from being eaten before the seeds inside are ripe.  Once the seeds are ready the berries advertise by turning red.  Migrating birds read the ads, eat the berries, but pass the hard seeds undamaged.  By the time bird digestion is complete many miles are under wing and the seeds are deposited, with a dollop of fertilizer, in a new location.  In this way dogwoods move to new locations.  


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