Monday, May 12, 2014

Better Late than Never - Spring at Last!

     Every year I make note and mark the timing of certain landmark changes in the advance of spring. This year was an especially bad winter and as expected things were especially late in blooming and breaking their winter dormancy.  This is a somewhat unscientific averaging of observations of when I notice what I see to be landmark plant responses to the spring.  The observations have been taken over a period of twenty years and have shown an interesting trend.
Rose Cane and woods - Feb 13, 2014
     First of all, the landmark start times have varied wildly over the years with some years having very early starts and some being quite late.  This year was later than any that I have observed.  Yes, Virginia, it really was a very long and cold winter.  You were not dreaming that or exaggerating your suffering.
      The scientist in me is always fascinated to note that the dates always manage to converge to a common start time by May.  No matter how bad, or mild, the winter, at some point the plants begin their start at roughly the same date, and that point in the years seems to be early May.  That indicates that weather and temperature definitely impacts the breaking of early spring dormancy, but at some point in the year the diurnal period (the length of the day) takes over.  This year is no exception.
     The following is a listing of what I have noticed over the years:

          Red Maple - Average blooming start Jan. 20 - 2014 blooming start March 1
           - 1.5 months late
          Daffodils - Average blooming start Feb. 15 - 2014 blooming start March 15
           - 1 month late
          Oak / Pine - Average blooming start March 25 - 2014 blooming start April 7
           - 2 weeks late
          Azalea / wild iris -  Average blooming start April 20 - 2014 blooming start April 25
           - 1 week late
          Wild and hybrid rose - Average blooming start May 15 - 2014 blooming start May 12
           - on time

     It is interesting to notice this for more than just the fact that eventually the plants manage to right themselves and reach a predictable state.  It is also interesting because there is so very much debate concerning climate change.  I have listened to many poorly informed people this year claiming that this year was a perfect example of the fact that climate change is a hoax.  What they are ignoring is that one of the symptoms of climate change is just what happened this year - wildly variable and extreme temperatures.  This year Alaska had a number of days during the winter that were actually warmer than we were experiencing here in North Carolina.  We had a cold winter due to arctic air moving down into the middle of the country rather than remaining in the north where it is normally expected.  This is not a normal event.  I have noticed other things in the past twenty years.  We have greater extremes in rainfall.  We have had several years of drought and then followed them with excessively wet years.  I realize that twenty years of observations are a very short period of time in comparison to the life span of the earth and that one weird year does not indicate a trend.  However, I also am alarmed by the rapid change that I am seeing.  You cannot keep track of the advances of the year and not see an overall change.

Rose Canes and woods - May 12, 2014
    I am also impressed by the resiliency of nature to right itself.  Eventually the plants do bloom, leaves do come out and grow.  On years that the winters are especially cold and long, I have noticed that growth moves quickly to catch up.  Leaves that emerge early in mild springs seem to mature much more slowly than leaves that emerge later in the year due to a cold spring.  They seem to reach maturity at roughly the same time.  I have also noticed through the years that on years when spring came early, blooming was spread out over a longer period of time with less actually blooms at any particular point in time.  On cold years, blooming appears to be later but with more things blooming at one time.  Somehow, the passage of spring manages to even itself out.
     Let us all hope that nature can do what we as people cannot seem to be able to do.  We must work to stop the actions that we as humans have done to initiate climate change.  Maybe, if we can do that, nature can take over to right the wrong that we humans have caused.