Olympic Habitat Development Study
US FOREST SERVICE

 

Station 1 - CONTROL

We start in the control stand which was not treated. Each of our 8 study sites has a control area 6 to 9 ha16 to 22 acres in size. Control areas give you an idea of what the area looked like before the study began -- and provide a standard against which we can judge the effects of our management treatments.

•  The Fresca control stand is dense (high overstory tree cover) with very little understory vegetation. Understory vegetation is limited to plants which are very tolerant of shade.

•  The stand is dense because of the large numbers of trees which naturally regenerated and because it has not been thinned at any time in its life.

•  Tree growth has slowed as the stand aged and suppression mortality (Suppression mortality refers to trees which die in dense stands due to lack of resources. This contrasts with mortality associated with insects, disease or fire) is occurring.

•  The ratio of overstory tree height to diameter was 70 (meters of height to meters of stem diameter) in 1994. This is moderately high and means the stand is more susceptible to tree blowdown in major wind storms than it would be if the ratio was lower (See Tree Station 1 for more information).


 

Dense canopy cover in our control area.
Shade tolerant plants are the only ones that survive under the thick canopy at the control. Dense canopy cover in our control area. A control area provides a basis to compare our treatments against.
Dense canopy cover in our control area.