Olympic Habitat Development Study
US FOREST SERVICE

 

Station 2 -SKIPS

The understory vegetation in the skips (unthinned areas) responded in the same general way vegetation did in the control area (Station 1). There was very little change in plant cover from year 0 (pretreatment) to year 3 (post-treatment) (graph)Chart of cover of herbs and shrubs over 10 years in the skips. but there was an increase in cover from year 3 to year 7 followed by a decline at year 10. The incease in cover for herbaceous plants from year 3 to 7 was very similiar to that seen in the control area and would be attributed to the same factor -- an increase in light due to top and branch breakage after several ice storms.

The biggest increase in herbaceous cover (graph) Chart of cover of deer fern, wood sorrel, and false lily of the valley over 10 years in the skips.were for wood sorrel, deer fern, and false lily-of-the-valley. False lily-of-the-valley was the only one where cover continued to increase from year 7 to year 10 but cover was still <10%. The cover of all 3 species changed very little from year 10 to year 17.

The increase in cover for the shrubs from year 3 to year 7 was much higher than we would have expected just due to ice storms. In this case, we also increased our sample size for vegetation plots between year 3 and 7 and sampled some plots with higher shrub cover. Cover declined from year 7 to 17.


 

Wood sorrel (Oxalis oregana) in a skip area. It contains oxalic acid (also found in rhubarb and spinach), a potentially harmful compound if consumed in substantial amounts.
The saprophytic Indianpipe (Monotropa uniflora) grows in moist, shady places like the skip areas. Wood sorrel (Oxalis oregana) in a skip area. It contains oxalic acid (also found in rhubarb and spinach), a potentially harmful compound if consumed in substantial amounts. The wood sorrel spreads by subterranean rhizomes forming a green carpet in the forest floor.
Wood sorrel (Oxalis oregana) in a skip area. It contains oxalic acid (also found in rhubarb and spinach), a potentially harmful compound if consumed in substantial amounts.