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Vegetation Update Title Page
tree_ftree_f Tables

Table 6.   Percent frequency of occurrence and percent cover of rooted, floating-leaf vegetation by year, study reach, and aquatic strata (n = number of sites, Frq = percent frequency of occurrence, SE = ± standard error, Cov = percent cover). In 1998, sites were selected from depths less than or equal to 3 m.  After 1998, the criteria was changed to less than or equal to 2.5 m; therefore, any sites between 2.5 and 3 m were dropped from the 1998 analysis for comparison purposes. A dash (–) indicates stratum was not sampled.

Pool 4
Contiguous backwater,
upper
Contiguous backwater, lower
Isolated backwater
Year
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
1998
74
4.1
2.3
4.1
2.3
157
38.2
3.9
17.3
2.3
31
54.8
9.1
24.5
5.8
1999
75
5.3
2.6
1.6
0.8
160
28.1
3.6
8.1
1.3
34
41.2
8.6
8.8
1.9
2000
100
5.0
2.2
4.2
2.0
179
26.3
3.3
5.7
0.7
32
46.9
9.0
18.8
4.7
2001
100
3.0
1.7
0.6
0.3
176
21.6
3.1
6.0
1.1
50
44.0
7.1
8.8
1.4
2002
100
6.0
2.4
1.4
0.6
180
26.7
3.3
6.0
0.9
30
50.0
9.3
10.7
2.1
2003a
92
4.3
2.1
1.1
0.6
165
37.0
3.8
11.6
1.5
–
–
–
–
–
2004
102
3.9
1.9
1.2
0.7
181
27.6
3.3
8.1
1.3
32
53.1
9.0
13.1
2.9
2005
90
6.7
2.6
1.3
0.5
108
39.8
4.7
13.1
2.1
20
30.0
10.5
9.0
3.4
2006
90
3.3
1.9
1.8
1.1
110
43.6
4.8
17.6
2.5
11
45.5
15.7
27.3
11.8
aData were provided by the U.S. Fish and Wildlife Service and the Division of Fisheries, Minnesota Department of Natural Resources.

 

Pool 4
Lake Pepin, upper
Lake Pepin, lower
Main channel border,
upper
Year
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
1998
57
0.0
0.0
0.0
0.0
29
0.0
0.0
0.0
0.0
9
0.0
0.0
0.0
0.0
1999
65
0.0
0.0
0.0
0.0
35
0.0
0.0
0.0
0.0
12
0.0
0.0
0.0
0.0
2000
75
0.0
0.0
0.0
0.0
75
0.0
0.0
0.0
0.0
30
0.0
0.0
0.0
0.0
2001
75
0.0
0.0
0.0
0.0
75
0.0
0.0
0.0
0.0
30
0.0
0.0
0.0
0.0
2002
75
0.0
0.0
0.0
0.0
75
0.0
0.0
0.0
0.0
30
0.0
0.0
0.0
0.0
2003a
–
–
–
–
–
–
–
–
–
–
26
0.0
0.0
0.0
0.0
2004
77
0.0
0.0
0.0
0.0
77
0.0
0.0
0.0
0.0
31
0.0
0.0
0.0
0.0
2005
59
1.7
1.7
0.3
0.3
50
0.0
0.0
0.0
0.0
20
0.0
0.0
0.0
0.0
2006
60
0.0
0.0
0.0
0.0
50
0.0
0.0
0.0
0.0
20
0.0
0.0
0.0
0.0
aData were provided by the U.S. Fish and Wildlife Service and the Division of Fisheries, Minnesota Department of Natural Resources.

 

Pool 4
Main channel border,
lower
Secondary channel,
upper
Secondary channel,
lower
Year
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
1998
37
0.0
0.0
0.0
0.0
47
0.0
0.0
0.0
0.0
65
9.2
3.6
4.0
2.0
1999
48
0.0
0.0
0.0
0.0
61
1.6
1.6
0.3
0.3
59
3.4
2.4
1.4
1.1
2000
40
0.0
0.0
0.0
0.0
40
0.0
0.0
0.0
0.0
60
6.7
3.2
1.3
0.6
2001
40
2.5
2.5
0.5
0.5
40
0.0
0.0
0.0
0.0
60
1.7
1.7
0.3
0.3
2002
40
2.5
2.5
0.5
0.5
40
0.0
0.0
0.0
0.0
60
5.0
2.8
1.0
0.6
2003a
23
0.0
0.0
0.0
0.0
39
0.0
0.0
0.0
0.0
53
3.8
2.6
0.8
0.5
2004
41
0.0
0.0
0.0
0.0
41
0.0
0.0
0.0
0.0
61
0.0
0.0
0.0
0.0
2005
30
0.0
0.0
0.0
0.0
30
0.0
0.0
0.0
0.0
39
5.1
3.6
2.6
2.1
2006
30
0.0
0.0
0.0
0.0
30
0.0
0.0
0.0
0.0
40
7.5
4.2
2.5
1.6
aData were provided by the U.S. Fish and Wildlife Service and the Division of Fisheries, Minnesota Department of Natural Resources.

 

Pool 8
Contiguous backwater
Isolated backwater
Impounded
Year
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
1998
172
47.7
3.8
27.3
2.7
28
71.4
8.7
51.4
8.2
170
1.8
1.0
0.8
0.6
1999
172
49.4
3.8
23.1
2.4
28
71.4
8.7
55.7
8.2
225
2.7
1.1
1.6
0.8
2000
175
49.1
3.8
17.7
2.0
30
70.0
8.5
48.7
8.2
225
3.1
1.2
1.2
0.6
2001
175
36.6
3.7
12.6
1.6
50
76.0
6.1
51.6
5.7
225
7.6
1.8
1.8
0.5
2002
174
39.7
3.7
16.1
2.0
26
65.4
9.5
46.9
9.0
224
11.2
2.1
3.3
0.7
2003
174
42.0
3.8
18.9
2.2
30
66.7
8.8
54.0
8.1
225
10.7
2.1
5.2
1.2
2004
175
43.4
3.8
16.8
2.0
29
65.5
9.0
50.3
8.0
225
15.1
2.4
6.8
1.4
2005
110
55.5
4.8
16.0
1.8
20
80.0
9.2
56.0
9.4
185
18.4
2.9
7.9
1.6
2006
108
54.6
4.8
26.3
3.3
16
62.5
12.5
56.3
12.3
185
23.2
3.1
9.7
1.7

 

Pool 8
Main channel border
Secondary channel
Year
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
1998
53
1.9
1.9
1.1
1.1
93
6.5
2.6
2.2
1.0
1999
70
0.0
0.0
0.0
0.0
100
7.0
2.6
2.6
1.2
2000
99
1.0
1.0
0.2
0.2
120
5.8
2.1
1.7
0.7
2001
100
4.0
2.0
2.4
1.3
120
6.7
2.3
1.3
0.5
2002
100
4.0
2.0
2.8
1.5
120
9.2
2.6
2.8
1.0
2003
100
4.0
2.0
2.2
1.2
120
10.8
2.8
3.3
1.0
2004
100
4.0
2.0
2.6
1.4
120
5.0
2.0
1.0
0.4
2005
70
4.3
2.4
1.1
0.7
65
7.7
3.3
1.8
0.8
2006
70
4.3
2.4
2.3
1.6
65
10.8
3.9
3.7
1.7

 

Pool 13
Contiguous backwater
Isolated backwater
Impounded
Year
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
1998
170
32.4
3.6
18.1
2.6
28
35.7
9.2
27.9
8.0
209
10.0
2.1
6.1
1.5
1999
170
37.6
3.7
21.8
2.8
30
33.3
8.8
14.0
4.5
210
11.4
2.2
8.0
1.7
2000
198
39.4
3.5
23.0
2.6
30
40.0
9.1
8.0
1.8
210
12.4
2.3
7.0
1.4
2001
198
42.4
3.5
23.3
2.5
59
16.9
4.9
3.4
1.0
209
17.2
2.6
11.2
2.0
2002
200
44.5
3.5
16.6
1.8
30
36.7
8.9
7.3
1.8
209
15.8
2.5
8.1
1.6
2003
200
50.0
3.5
20.7
2.1
30
36.7
8.9
22.0
6.7
210
16.7
2.6
8.6
1.6
2004
220
49.5
3.4
17.2
1.7
34
41.2
8.6
15.9
4.9
236
16.1
2.4
9.0
1.6
2005
120
50.8
4.6
18.0
2.2
25
60.0
10.0
40.8
8.8
175
16.0
2.8
8.8
1.8
2006
120
50.8
4.6
31.0
3.4
25
56.0
10.1
20.8
5.0
175
23.4
3.2
15.3
2.4

 

Pool 13
Main channel border
Secondary channel
Year
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
1998
62
0.0
0.0
0.0
0.0
62
3.2
2.3
0.6
0.5
1999
70
0.0
0.0
0.0
0.0
70
0.0
0.0
0.0
0.0
2000
70
0.0
0.0
0.0
0.0
70
2.9
2.0
0.6
0.4
2001
70
0.0
0.0
0.0
0.0
70
1.4
1.4
0.6
0.6
2002
70
0.0
0.0
0.0
0.0
70
1.4
1.4
1.1
1.1
2003
70
0.0
0.0
0.0
0.0
70
2.9
2.0
1.1
0.9
2004
79
0.0
0.0
0.0
0.0
79
3.8
2.2
0.8
0.4
2005
80
0.0
0.0
0.0
0.0
50
2.0
2.0
0.4
0.4
2006
80
0.0
0.0
0.0
0.0
50
2.0
2.0
1.6
1.6

 

Pool 26
Contiguous backwater
Isolated backwater,
Illinois River
Isolated backwater, Mississippi River
Year
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
1998
50
10.0
4.3
2.8
1.4
160
13.1
2.7
3.8
0.9
30
3.3
3.3
1.3
1.3
1999
80
1.3
1.3
0.8
0.8
160
2.5
1.2
1.5
0.8
50
0.0
0.0
0.0
0.0
2000
79
15.2
4.1
3.0
0.8
95
7.4
2.7
1.7
0.6
42
9.5
4.6
2.4
1.2
2001
80
2.5
1.8
0.8
0.6
94
11.7
3.3
5.5
1.9
60
5.0
2.8
1.0
0.6
2002
73
11.0
3.7
5.8
2.2
100
7.0
2.6
3.4
1.6
57
14.0
4.6
2.8
0.9
2003a
80
5.0
2.5
1.8
1.1
100
16.0
3.7
5.2
1.6
60
10.0
3.9
3.0
1.3
2004
110
14.5
3.4
2.9
0.7
132
1.5
1.1
0.3
0.2
58
12.1
4.3
5.5
2.4
aData were provided by the Illinois Natural History Survey based on a grant from the National Great Rivers Research and Education Center.

 

Pool 26
Impounded
Main channel border,
Illinois River
Year
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
1998
27
0.0
0.0
0.0
0.0
47
0.0
0.0
0.0
0.0
1999
80
0.0
0.0
0.0
0.0
50
0.0
0.0
0.0
0.0
2000
39
2.6
2.6
0.5
0.5
40
0.0
0.0
0.0
0.0
2001
40
0.0
0.0
0.0
0.0
40
0.0
0.0
0.0
0.0
2002
40
0.0
0.0
0.0
0.0
40
0.0
0.0
0.0
0.0
2003a
40
0.0
0.0
0.0
0.0
40
0.0
0.0
0.0
0.0
2004
56
0.0
0.0
0.0
0.0
56
0.0
0.0
0.0
0.0
aData were provided by the Illinois Natural History Survey based on a grant from the National Great Rivers Research and Education Center.

 

Pool 26
Main channel border,
Mississippi River
Secondary channel
Year
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
1998
121
0.0
0.0
0.0
0.0
84
0.0
0.0
0.0
0.0
1999
137
2.2
1.3
0.4
0.3
90
0.0
0.0
0.0
0.0
2000
47
0.0
0.0
0.0
0.0
50
0.0
0.0
0.0
0.0
2001
49
0.0
0.0
0.0
0.0
50
0.0
0.0
0.0
0.0
2002
50
0.0
0.0
0.0
0.0
50
0.0
0.0
0.0
0.0
2003a
50
0.0
0.0
0.0
0.0
50
0.0
0.0
0.0
0.0
2004
69
0.0
0.0
0.0
0.0
69
0.0
0.0
0.0
0.0
aData were provided by the Illinois Natural History Survey based on a grant from the National Great Rivers Research and Education Center.

 

La Grange Pool
Contiguous backwater
Isolated backwater
Lakesa
Year
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
1998
173
0.0
0.0
0.0
0.0
179
0.6
0.6
0.1
0.1
–
–
–
–
–
1999
190
0.5
0.5
0.2
0.2
188
0.5
0.5
0.1
0.1
–
–
–
–
–
2000
100
1.0
1.0
0.4
0.4
138
9.4
2.5
1.9
0.5
57
33.3
6.3
20.4
4.3
2001
100
1.0
1.0
0.6
0.6
129
0.0
0.0
0.0
0.0
57
28.1
6.0
14.7
3.8
2002
100
4.0
2.0
1.0
0.5
139
1.4
1.0
0.3
0.2
59
37.3
6.3
21.7
4.5