"Nature Guide Journal"

5 April 2001

Gardeners know about them.  Ecologists know about them.  You know about them, too:  Microclimates.

Our mid-latitude location, combined with the moderating effects of the Pacific Ocean and the prevailing westerly winds, give the Oregon Coast in general a moderate, temperate climate.

In addition to the state-wide climate patterns, variations in climate also occur on a regional scale.  Coos County has several discernable climates; astute gardeners know that what grows well in Coquille may not thrive in Charleston.  A given location's distance from the temperature-moderating sea, as well as it's elevation and wind exposure, combine to affect the extremes of temperature at a site, as well as the amount of moisture available.  The sea's influence is so great, in fact, that the climate generally varies more ten miles inland from the beach than it does a hundred miles north or south of that same spot on the beach.

Where a specific plant lives is determined by the climate, amount and kind of available water, type of soil and the amount of organic material in the soil, air-borne particles (mist or salt spray, for examples), presence of parent plants, and, sometimes, the presence of necessary companion plants or animals.  It's not just an issue for the mature plants:  the microenvironment needs to be favorable for the germination of a given plant's seed, as well as favorable to the established plant, for the species to thrive in a given location.

Experienced gardeners know the microclimates of their particular plots:  damp and shady; hot and dry; exposed or sheltered.  And, successful gardeners are good at matching the plants to the microenvironments.

The change in climate between inland and near-shore locations is a profound determiner of plant communities.  For example, while Douglas fir, Sitka spruce, and red alder grow well both near the sea and inland, Oregon myrtle, madrone, and big-leaf maple are rarely found near the cool and misty shore.

Very small scale variations in climate that may seem inconsequential can have a great affect on plant communities in nature, as well.  In other regions of the northern hemisphere where conditions are marginal for moss, for example, moss may only grow on the shadier, moister side of a tree trunk.  Our climates are generally more favorable for moss, so it isn't limited to the north sides of trees and doesn't make a good compass.

Hikers and bikers notice the changes in temperature and humidity as they drop down into a wind-sheltered valley or enter a deeply shaded forest.  Often, there is a change in the mix of plant species or in the numbers of plants that corresponds to that change in temperature and humidity.  If obvious differences in available water (near a stream, for example) can be eliminated as a causing factor, the change in plant communities is most likely caused by that change in microclimate.

Tracking the microclimates gives the astute hiker or biker an added dimension in interpreting the patterns in natural communities.

Wavecrest Discoveries can craft your personal discovery of this delightful part of our world by customizing one of our distinctive guided excursions.   Our walks, tours, and special activities are wonderful ways to explore this fascinating region—and are the perfect entertainment for guests.