Global Warming - Trees
Forests are
in the process of re-organizing themselves to a new set of conditions. About 15
years ago while kayaking in the Gulf Islands I noticed that both young and old
Arbutus trees appeared to be dying. A forest pathologist suggested that due to
changing temperatures the Arbutus had likely become more susceptible to a
fungus which was causing mortality as evidenced by blackened foliage. Locally,
Arbutus are at the northernmost limit of their natural range extending to southern
California and so are especially sensitive to change. Now, after having
experienced 3 summers of drought, Western red cedar trees are in the process of
adapting.
Cedars prefer moist soil conditions and some are showing signs of
stress, especially along harsh south-facing roadside edges, where droughty
conditions already existed. Some household hedges are also showing signs of
moisture stress.
With more intense disturbances during winter, strong winds, wet
snow and heavy rains have caused physical damage to trees. Whole trees, tops
and branches have come down particularly over the past few winters.
We can likely
expect another summer of drier than usual conditions coming up, so remember to
water your trees, especially those cedars.
Nancy Smith