Upper Midwest Environmental Sciences Center

Table 6. Frequency RFA strata
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 3.6 2.1 157 38.2 3.9 13.5 2.1 31 54.8 9.1 19.0 5.2
1999
 75 5.3 2.6 1.1 0.6 160 28.1 3.6 5.3 1.0 34 41.2 8.6 4.7 1.1
2000
 100 5.0 2.2 3.7 1.8 179 26.3 3.3 3.1 0.4 32 46.9 9.0 14.1 4.1
2001
 100 3.0 1.7 0.3 0.2 176 21.6 3.1 3.9 0.8 50 44.0 7.1 4.4 0.7
2002
 100 6.0 2.4 0.8 0.4 180 26.7 3.3 3.3 0.6 30 50.0 9.3 5.7 1.2
2003a
 92 4.3 2.1 0.7 0.4 165 37.0 3.8 7.9 1.3
–
–
–
–
–
2004
 102 3.9 1.9 0.8 0.5 181 27.6 3.3 5.3 1.0 32 53.1 9.0 7.8 2.3
2005
 90 6.7 2.6 0.7 0.3 108 39.8 4.7 9.2 1.8 20 30.0 10.5 6.0 2.4
2006
 90 3.3 1.9 1.4 1.0 110 43.6 4.8 13.3 2.1 11 45.5 15.7 22.7 10.6
2007
 88 5.7 2.5 4.0 1.9 110 39.1 4.7 10.6 2.1 10 40.0 16.3 12.0 7.1
2008
 90 6.7 2.6 0.7 0.3 110 46.4 4.8 9.0 1.6 20 40.0 11.2 7.0 2.4
2009 89 3.4 1.9 0.8 0.5 110 55.5 4.8 10.6 1.6 20 55.0 11.4 12.5 4.7
2010 90 2.2 1.6 0.2 0.2 109 55.0 4.8 8.1 1.3 19 52.6 11.8 20.0 5.9
2011 90 2.2 1.6 0.2 0.2 110 39.1 4.7 6.6 1.2 19 57.9 11.6 10.0 4.6
2012 90 6.7 2.6 0.7 0.3 110 42.7 4.7 7.2 1.4 20 20.0 9.2 2.0 0.9
2013 90 4.4 2.2 0.4 0.2 110 28.2 4.3 3.9 1.0 20 35.0 10.9 3.5 1.1
2014 89 3.4 1.9 0.3 0.2 109 41.3 4.7 4.9 0.7 19 47.4 11.8 4.7 1.2
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 0.2 0.2 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
2007
 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
2008
 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
2009 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
2010 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
2011 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
2012 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
2013 59 0.0 0.0 0.0 0.0 50 0.0 0.0 0.0 0.0 20 5.0 5.0 0.5 0.5
2014 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 3.1 1.8
1999
 48 0.0 0.0 0.0 0.0 61 1.6 1.6 0.2 0.2 59 3.4 2.4 1.0 0.9
2000
 40 0.0 0.0 0.0 0.0 40 0.0 0.0 0.0 0.0 60 6.7 3.2 0.7 0.3
2001
 40 2.5 2.5 0.3 0.3 40 0.0 0.0 0.0 0.0 60 1.7 1.7 0.2 0.2
2002
 40 2.5 2.5 0.3 0.3 40 0.0 0.0 0.0 0.0 60 5.0 2.8 0.5 0.3
2003a
 23 0.0 0.0 0.0 0.0 39 0.0 0.0 0.0 0.0 53 3.8 2.6 0.4 0.3
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 2.1 1.8
2006
 30 0.0 0.0 0.0 0.0 30 0.0 0.0 0.0 0.0 40 7.5 4.2 1.8 1.3
2007
 30 0.0 0.0 0.0 0.0 30 0.0 0.0 0.0 0.0 40 15.0 5.7 1.5 0.6
2008
 30 0.0 0.0 0.0 0.0 30 0.0 0.0 0.0 0.0 40 2.5 2.5 0.3 0.3
2009 30 0.0 0.0 0.0 0.0 30 0.0 0.0 0.0 0.0 40 15.0 5.7 2.5 1.3
2010 30 0.0 0.0 0.0 0.0 30 0.0 0.0 0.0 0.0 40 7.5 4.2 0.8 0.4
2011 30 0.0 0.0 0.0 0.0 30 0.0 0.0 0.0 0.0 40 7.5 4.2 0.8 0.4
2012 20 6.7 4.6 0.7 0.5 30 0.0 0.0 0.0 0.0 40 5.0 3.5 1.0 0.8
2013 30 0.0 0.0 0.0 0.0 30 0.0 0.0 0.0 0.0 40 7.5 4.2 0.8 0.4
2014 30 3.3 3.3 0.3 0.3 30 0.0 0.0 0.0 0.0 40 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 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 22.6 2.4 28 71.4 8.7 44.3 7.5 170 1.8 1.0 0.6 0.5
1999
 172 49.4 3.8 18.2 2.1 28 71.4 8.7 48.6 7.5 225 2.7 1.1 1.3 0.7
2000
 175 49.1 3.8 12.8 1.7 30 70.0 8.5 41.7 7.6 225 3.1 1.2 0.9 0.5
2001
 175 36.6 3.7 8.9 1.3 50 76.0 6.1 44.0 5.2 225 7.6 1.8 1.0 0.4
2002
 174 39.7 3.7 12.1 1.8 26 65.4 9.5 40.4 8.3 224 11.2 2.1 2.2 0.6
2003
 174 42.0 3.8 14.7 2.0 30 66.7 8.8 47.3 7.3 225 10.7 2.1 4.2 1.0
2004
 175 43.4 3.8 12.5 1.7 29 65.5 9.0 43.8 7.2 225 15.1 2.4 5.2 1.2
2005
 110 55.5 4.8 10.5 1.5 20 80.0 9.2 48.0 8.8 185 18.4 2.9 6.1 1.4
2006
 108 54.6 4.8 20.8 2.9 16 62.5 12.5 50.0 11.1 185 23.2 3.1 7.4 1.5
2007
 108 59.3 4.8 26.7 3.3 20 70.0 10.5 44.0 8.7 185 33.5 3.5 8.5 1.4
2008
 110 46.4 4.8 12.1 2.1 17 47.1 12.5 28.2 10.0 185 32.4 3.5 6.6 1.2
2009 110 60.0 4.7 16.2 2.1 18 55.6 12.1 34.4 8.9 184 37.0 3.6 7.5 1.2
2010 108 57.4 4.8 18.7 2.6 19 42.1 11.6 30.5 9.3 182 32.4 3.5 4.6 0.7
2011 110 45.5 4.8 10.9 2.0 19 63.2 11.4 41.1 9.4 183 19.1 2.9 2.8 0.5
2012 110 41.8 4.7 12.5 2.2 20 35.0 10.9 24.5 8.1 185 14.6 2.6 2.2 0.5
2013 110 40.9 4.7 5.5 0.9 20 70.0 10.5 42.0 9.4 185 24.3 3.2 4.5 0.8
2014 110 47.3 4.8 8.2 1.2 20 70.0 10.5 36.0 7.6 185 24.3 3.2 3.2 0.7

 

Pool 8
Main channel border
Secondary channel
Year
n
Frq
± SE
Cov
± SE
n
Frq
± SE
Cov
± SE
1998
 53 1.9 1.9 0.9 0.9 93 6.5 2.6 1.5 0.8
1999
 70 0.0 0.0 0.0 0.0 100 7.0 2.6 1.9 1.0
2000
 99 1.0 1.0 0.1 0.1 120 5.8 2.1 1.1 0.5
2001
 100 4.0 2.0 2.0 1.2 120 6.7 2.3 0.7 0.2
2002
 100 4.0 2.0 2.4 1.4 120 9.2 2.6 1.9 0.8
2003
 100 4.0 2.0 1.8 1.1 120 10.8 2.8 2.3 0.8
2004
 100 4.0 2.0 2.2 1.2 120 5.0 2.0 0.5 0.2
2005
 70 4.3 2.4 0.7 0.5 65 7.7 3.3 1.1 0.5
2006
 70 4.3 2.4 1.9 1.4 65 10.8 3.9 2.6 1.5
2007
 70 1.4 1.4 0.1 0.1 65 18.5 4.8 3.7 1.5
2008
 70 4.3 2.4 0.7 0.5 65 18.5 4.8 2.5 0.8
2009 70 4.3 2.4 0.4 0.2 65 12.3 4.1 1.2 0.4
2010 70 4.3 2.4 0.4 0.2 65 16.9 4.7 2.3 0.8
2011 70 2.9 2.0 0.3 0.2 65 13.8 4.3 1.4 0.4
2012 70 5.7 2.8 3.4 1.9 65 3.1 2.2 0.3 0.2
2013 70 1.4 1.4 0.4 0.4 65 6.2 3.0 0.6 0.3
2014 69 1.4 1.4 0.1 0.1 65 9.2 3.6 0.9 0.4

 

Pool 13
Contiguous backwater
Isolated backwater
Impounded
Year
n
Frq
± SE
Cov
± SE
n
Frq
± SE
Cov
± SE
n
Frq
SE
Cov
± SE
1998
 169 32.5 3.6 15.0 2.3 27 37.0 9.5 25.2 7.4 209 10.0 2.1 5.1 1.3
1999
 170 37.6 3.7 18.0 2.5 29 34.5 9.0 11.0 3.9 210 11.4 2.2 6.9 1.5
2000
 198 39.4 3.5 19.1 2.3 27 44.4 9.7 4.4 1.0 210 12.4 2.3 5.8 1.2
2001
 198 42.4 3.5 19.1 2.3 52 19.2 5.5 1.9 0.6 209 17.2 2.6 9.5 1.8
2002
 200 44.5 3.5 12.2 1.6 29 37.9 9.2 3.8 0.9 209 15.8 2.5 6.6 1.4
2003
 200 50.0 3.5 15.7 1.9 29 37.9 9.2 19.0 6.1 210 16.7 2.6 6.9 1.4
2004
 219 49.8 3.4 12.3 1.5 31 45.2 9.1 12.9 4.8 236 16.1 2.4 7.4 1.4
2005
 118 51.7 4.6 13.1 1.9 24 62.5 10.1 36.3 8.3 175 16.0 2.8 7.2 1.6
2006
 119 51.3 4.6 26.1 3.0 23 60.9 10.4 16.5 4.5 175 23.4 3.2 13.0 2.1
2007
 118 48.3 4.6 26.0 3.4 22 50.0 10.9 21.4 7.1 172 22.1 3.2 11.9 2.1
2008
 115 50.4 4.7 10.8 1.8 23 43.5 10.6 13.9 5.9 175 13.7 2.6 2.4 0.7
2009 119 56.3 4.6 19.4 2.6 24 62.5 10.1 27.1 7.5 175 23.4 3.2 12.3 2.1
2010 120 41.7 4.5 21.0 3.0 23 56.5 10.6 27.4 7.6 175 25.7 3.3 9.5 1.8
2011 120 38.3 4.5 9.5 2.0 25 56.0 10.1 10.4 3.7 175 18.9 3.0 4.2 1.0
2012 120 34.2 4.3 14.4 2.6 23 39.1 10.4 15.2 5.7 175 18.9 3.0 6.1 1.4
2013 120 51.7 4.6 13.2 2.1 25 52.0 10.2 5.2 1.0 175 18.9 3.0 3.6 0.9
2014 120 45.0 4.6 15.3 2.2 24 41.7 10.3 6.7 2.1 175 22.3 3.2 6.7 1.4

 

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 0.3 0.2
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 0.3 0.2
2001
 70 0.0 0.0 0.0 0.0 70 1.4 1.4 0.4 0.4
2002
 70 0.0 0.0 0.0 0.0 70 1.4 1.4 1.0 1.0
2003
 70 0.0 0.0 0.0 0.0 70 2.9 2.0 0.9 0.7
2004
 79 0.0 0.0 0.0 0.0 79 3.8 2.2 0.4 0.2
2005
 80 0.0 0.0 0.0 0.0 50 2.0 2.0 0.2 0.2
2006
 80 0.0 0.0 0.0 0.0 50 2.0 2.0 1.4 1.4
2007
 80 1.3 1.3 0.4 0.4 50 8.0 3.9 4.0 2.5
2008
 80 1.3 1.3 0.1 0.1 50 2.0 2.0 0.2 0.2
2009 77 2.6 1.8 0.8 0.7 48 6.3 3.5 0.6 0.4
2010 80 1.3 1.3 0.4 0.4 50 4.0 2.8 0.4 0.3
2011 80 0.0 0.0 0.0 0.0 50 2.0 2.0 0.2 0.2
2012 80 1.3 1.3 0.1 0.1 50 0.0 0.0 0.0 0.0
2013 79 0.0 0.0 0.0 0.0 48 4.2 2.9 0.4 0.3
2014 80 0.0 0.0 0.0 0.0 50 0.0 0.0 0.0 0.0

 

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 1.8 1.1 160 13.1 2.7 2.4 0.7 30 3.3 3.3 1.0 1.0
1999
 80 1.3 1.3 0.6 0.6 160 2.5 1.2 1.3 0.7 50 0.0 0.0 0.0 0.0
2000
 79 15.2 4.1 1.5 0.4 95 7.4 2.7 0.9 0.4 42 9.5 4.6 1.4 0.8
2001
 80 2.5 1.8 0.5 0.4 94 11.7 3.3 4.4 1.6 60 5.0 2.8 0.5 0.3
2002
 80 10.0 3.4 4.3 1.8 100 7.0 2.6 2.7 1.4 57 14.0 4.6 1.4 0.5
2003a
 80 5.0 2.5 1.3 0.9 100 16.0 3.7 3.6 1.4 60 10.0 3.9 2.0 1.0
2004
 110 14.5 3.4 1.5 0.3 132 1.5 1.1 0.2 0.1 58 12.1 4.3 4.3 2.1
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
0.3
0.3
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
0.2
0.1
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 0.3 0.3 138 9.4 2.5 0.9 0.2 57 33.3 6.3 17.0 3.7
2001
 100 1.0 1.0 0.5 0.5 129 0.0 0.0 0.0 0.0 57 28.1 6.0 11.9 3.3
2002
 100 4.0 2.0 0.6 0.3 139 1.4 1.0 0.1 0.1 59 37.3 6.3 18.0 4.0
2003b
 100 1.0 1.0 0.1 0.1 117 1.7 1.2 0.3 0.3 60 36.7 6.3 27.7 5.1
2004
 128 0.0 0.0 0.0 0.0 175 1.7 1.0 0.4 0.3 74 37.8 5.7 24.6 4.2
aThe lakes stratum was added to sampling in 2000.
bData were provided by the Illinois Natural History Survey based on a grant from the Illinois Department of Natural Resources.

 

La Grange Pool
Main channel border
Secondary channel
Year
n
Frq
± SE
Cov
± SE
n
Frq
± SE
Cov
± SE
1998
83
0.0
0.0
0.0
0.0
29
0.0
0.0
0.0
0.0
1999
120
0.0
0.0
0.0
0.0
40
0.0
0.0
0.0
0.0
2000
80
0.0
0.0
0.0
0.0
50
0.0
0.0
0.0
0.0
2001
78
0.0
0.0
0.0
0.0
50
0.0
0.0
0.0
0.0
2002
80
2.5
1.8
0.3
0.2
50
0.0
0.0
0.0
0.0
2003a
80
0.0
0.0
0.0
0.0
50
0.0
0.0
0.0
0.0
2004
103
0.0
0.0
0.0
0.0
65
0.0
0.0
0.0
0.0
aData were provided by the Illinois Natural History Survey based on a grant from the Illinois Department of Natural Resources.

 

Content manager: Danelle Larson


Page Last Modified: April 17, 2018