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2017 Leaf Emergence – Earliest Ever?

While walking the family dog on February 16th in Carver, Minnesota along the bluffs of the Minnesota River I noticed something very surprising and a little concerning.  Sambucus racemes, our native Red-berried Elderberry) has begun leaving out!

Sambucus racemosa Leaf Out

Sambucus racemosa Buds

Sumbucus racemosa Leaves

February 2017 is looking like we will be keeping the trend of 16 straight months of above normal temperatures.  With temperatures predicted to be almost thirty degrees above normal for the next four days how will the leaf-out in Minnesota be affected?  The study of the emergence of timing of leaf out is called phenology and has been studied and tracked for years by scientists and amateur naturalist.  The general trend has been leaves coming out of winter dormancy earlier and earlier, but I have never seen a deciduous shrub leaf-out in February.  Let me know what you are witnessing we all come out of our winter hibernation.

A larger question is, what impact does earlier leaf emergence have on our fauna?  Many insect and bird species are dependent leaf-out for food and shelter.  The timing is especially important for species that have gone through winter with little available food, or returning birds species completing their migration back to northern nesting grounds.  Back in 1854 Henry David Thoreau was aware of the relationship between migrating birds and the leaf-out, “To-day the air is full of birds; they attend the opening the buds.  Trees begin to leaf, and the leaf-like wings of birds are in the air.  The buds start, then the insects, and then the birds.’  With the warming of our winters and spring coming earlier we can no longer take for granted the sequence of natural events.  What will be the impact of species?  Will they be able to adapt?  Will species expand their range or new species come into warmer habitats?  There are a lot of unanswered questions and no historical data to rely on since warming of our climatic has never been so rapid.

Share what you are seeing since only through observation and study can we all be part of the solution.