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Cover: Cover is high over a large area in this exclosure. In fact, in proportion to the <br />exclosure dimensions, this exclosure has the highest cover over the largest area. Of course, this <br />comparison is not actual]y valid as the shape of the exclosure was not defined here or in any of the <br />other exclosures by the extent of woody vegetation. The exclosure boundaries were defined primarily <br />for ease of building sturdy fences. Nevertheless, it is apparent that this exclosure contains the largest <br />expanse of cottonwood growth of the five exclosures. In fact, by comparison, Exclosure 5 is <br />approximating the kind of cover now seen in the two older exclosures (North and South Exclosures) <br />that are still intact and quite mature. <br />Cover here averages about 36% which, with six foot tall, fairly dense cottonwood trees, is <br />excellent. The trees here have not developed the type of branch spread seen in trees that are in the 10 <br />to 20 foot height range, so there is still a good deal of ground that is not overarched by cottonwood <br />branches. But as seen in the data, the northern exclosure cover is about 94%. This is about as dense <br />as the cover in this kind of vegetation can get and is considerably greater than what is found in the <br />mature forest. It is probably an overestimation of cover due to overlap of trees. The south transect <br />showed a 20% cover, but this is actually low for what is really there. Along the transect there are a <br />couple of significant gaps in the tree cover that rapidly reduce the total cover. If those gaps are <br />removed from the data and the length of woody vegetation occupied transect broken into two or three <br />units, the cover is, in fact, comparable to the north transect. If the cover was measured using vertical <br />projection along a line intercept then the total cover is estimated to be about 30% to 50%. Line <br />intercept cover will be added to the sampling scheme for Exclosures 3 and 5 next year, but at this <br />point that is not a meaningful measurement in the other three exclosures. <br />Exclosure Analysis Results for 2007 - Exclosure 5 (most northerly) <br />parameter Transect 1 <br />(southern) Transect 2 <br />(northern) All Transects All Woody <br />Plants <br />ttl transect ]ngth 208 feet 146.5 feet 354.5 feet 354.5 feet <br />veg transect ]ngth 196 feet 55 feet 251 feet 251 feet <br />transect width 6 feet 6 feet 6 feet 6 feet <br />ttl transect area 1248 sq ft 879 sq ft 2127 sq ft 2127 sq ft <br />veg transect area 1176 sq ft 330 sq ft 1506 sq ft 1506 sq ft <br />2007 Annual Report Coal Creek Wetland Mitigation Permit DA 198811488 Page 22 <br />