Upper Midwest Environmental Sciences Center

Table 7. Frequency of Emergents - strata
Vegetation Update Title Page
tree_ftree_f Tables

Table 7.   Percent frequency of occurrence and percent cover of emergent 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 5.4 2.6 2.4 1.3 157 22.9 3.4 8.0 1.7 31 35.5 8.7 6.8 3.0
1999
 75 13.3 4.0 4.5 2.1 160 16.9 3.0 5.7 1.4 34 11.8 5.6 2.4 1.5
2000
 100 8.0 2.7 3.0 1.4 179 16.8 2.8 5.7 1.3 32 21.9 7.4 4.7 2.0
2001
 100 12.0 3.3 2.0 0.7 176 17.6 2.9 6.3 1.3 50 18.0 5.5 3.8 1.5
2002
 100 10.0 3.0 6.6 2.3 180 18.9 2.9 6.7 1.4 30 40.0 9.1 13.3 4.6
2003a
 92 0.0 0.0 0.0 0.0 165 17.6 3.0 7.3 1.7
–
–
–
–
–
2004
 102 5.9 2.3 1.6 0.9 181 27.6 3.3 15.5 2.3 32 37.5 8.7 13.1 5.0
2005
 90 5.6 2.4 1.4 0.8 108 17.6 3.7 8.6 2.4 20 25.0 9.9 5.5 2.5
2006
 90 7.8 2.8 3.7 1.7 110 27.3 4.3 15.6 2.9 11 45.5 15.7 13.6 8.1
2007
 88 15.9 3.9 7.3 2.3 110 25.5 4.2 13.3 2.7 10 50.0 16.7 23.0 10.8
2008
 90 22.2 4.4 7.6 2.2 110 26.4 4.2 12.6 2.6 20 50.0 11.5 12.0 4.7
2009 89 22.5 4.4 11.9 3.0 110 34.5 4.6 15.3 2.8 20 40.0 11.2 18.0 7.2
2010 90 22.2 4.4 10.7 2.7 109 33.9 4.6 11.8 2.2 19 42.1 11.6 14.7 6.5
2011 90 15.6 3.8 1.8 0.5 110 44.5 4.8 13.9 2.4 19 57.9 11.6 7.9 2.1
2012 90 11.1 3.3 2.2 0.9 110 50.0 4.8 12.1 2.1 20 25.0 9.9 6.5 3.1
2013 90 11.1 3.3 1.8 0.8 110 39.1 4.7 8.3 1.8 20 25.0 9.9 2.5 1.0
2014 89 9.0 3.0 1.3 0.5 109 44.0 4.8 10.3 1.9 19 21.1 9.6 2.1 1.0
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 25.0 13.1 2.5 1.3
2000
 75 0.0 0.0 0.0 0.0 75 0.0 0.0 0.0 0.0 30 6.7 4.6 2.0 1.7
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 1.3 1.3 0.1 0.1 75 1.3 1.3 0.1 0.1 30 0.0 0.0 0.0 0.0
2003a
–
–
–
–
–
–
–
–
–
–
 26 0.0 0.0 0.0 0.0
2004
 77 1.3 1.3 0.1 0.1 77 0.0 0.0 0.0 0.0 31 0.0 0.0 0.0 0.0
2005
 59 3.4 2.4 0.3 0.2 50 0.0 0.0 0.0 0.0 20 0.0 0.0 0.0 0.0
2006
 60 1.7 1.7 0.2 0.2 50 0.0 0.0 0.0 0.0 20 10.0 6.9 1.0 0.7
2007
 60 3.3 2.3 1.7 1.5 50 4.0 2.8 3.2 2.3 20 0.0 0.0 0.0 0.0
2008
 60 1.7 1.7 0.2 0.2 50 0.0 0.0 0.0 0.0 20 10.0 6.9 4.0 3.5
2009 60 0.0 0.0 0.0 0.0 50 2.0 2.0 1.4 1.4 20 10.0 6.9 5.0 4.5
2010 60 1.7 1.7 0.5 0.5 50 0.0 0.0 0.0 0.0 20 5.0 5.0 0.5 0.5
2011 60 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
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 0.0 0.0 0.0 0.0
2014 60 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
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 8.5 4.1 3.0 2.0 65 4.6 2.6 0.8 0.5
1999
 48 0.0 0.0 0.0 0.0 61 4.9 2.8 1.8 1.5 59 3.4 2.4 0.3 0.2
2000
 40 0.0 0.0 0.0 0.0 40 7.5 4.2 3.3 2.1 60 8.3 3.6 0.8 0.4
2001
 40 0.0 0.0 0.0 0.0 40 5.0 3.5 2.5 2.3 60 8.3 3.6 4.8 2.6
2002
 40 0.0 0.0 0.0 0.0 40 0.0 0.0 0.0 0.0 60 6.7 3.2 2.3 1.6
2003a
 23 0.0 0.0 0.0 0.0 39 0.0 0.0 0.0 0.0 53 3.8 2.6 0.4 0.3
2004
 41 0.0 0.0 0.0 0.0 41 4.9 3.4 0.5 0.3 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 7.7 4.3 2.8 2.3
2006
 30 3.3 3.3 3.0 3.0 30 6.7 4.6 3.3 3.0 40 15.0 5.7 7.0 3.4
2007
 30 0.0 0.0 0.0 0.0 30 20.0 7.4 6.7 3.5 40 17.5 6.1 3.8 2.3
2008
 30 0.0 0.0 0.0 0.0 30 10.0 5.6 1.0 0.6 40 20.0 6.4 6.0 3.1
2009 30 0.0 0.0 0.0 0.0 30 3.3 3.3 3.0 3.0 40 10.0 4.8 2.5 1.5
2010 30 0.0 0.0 0.0 0.0 30 13.3 6.3 4.0 3.0 40 7.5 4.2 0.8 0.4
2011 30 3.3 3.3 1.7 1.7 30 3.3 3.3 0.3 0.3 40 20.0 6.4 12.5 4.7
2012 30 3.3 3.3 0.3 0.3 30 3.3 3.3 0.3 .03 40 12.5 5.3 2.3 1.3
2013 30 0.0 0.0 0.0 0.0 30 10.0 5.6 3.0 2.4 40 17.5 6.1 3.8 1.9
2014 30 0.0 0.0 0.0 0.0 30 6.7 4.6 4.0 3.1 40 12.5 5.3 2.8 1.5
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 32.0 3.6 13.2 2.0 28 42.9 9.5 15.7 5.1 170 0.0 0.0 0.0 0.0
1999
 172 39.5 3.7 18.6 2.2 28 60.7 9.4 33.2 6.5 225 0.9 0.6 0.5 0.4
2000
 175 27.4 3.4 10.1 1.7 30 46.7 9.3 16.0 4.9 225 0.0 0.0 0.0 0.0
2001
 175 22.9 3.2 6.5 1.3 50 48.0 7.1 16.0 3.6 225 1.3 0.8 0.3 0.2
2002
 174 39.1 3.7 14.1 2.0 26 46.2 10.0 19.2 6.2 224 3.1 1.2 1.2 0.6
2003
 174 43.1 3.8 20.2 2.4 30 56.7 9.2 27.0 6.8 225 3.1 1.2 1.6 0.7
2004
 175 41.1 3.7 15.9 2.1 29 51.7 9.4 19.0 5.5 225 3.6 1.2 1.6 0.7
2005
 110 50.0 4.8 18.3 2.5 20 65.0 10.9 19.5 6.2 185 2.2 1.1 1.0 0.6
2006
 108 42.6 4.8 22.6 3.4 16 56.3 12.8 20.6 7.9 185 6.5 1.8 1.7 0.7
2007
 108 63.9 4.6 36.4 3.6 20 45.0 11.4 25.5 8.4 185 5.4 1.7 3.5 1.2
2008
 110 52.7 4.8 18.0 2.4 17 35.3 11.9 17.6 7.1 185 3.8 1.4 1.7 0.7
2009 110 58.2 4.7 29.8 3.3 18 44.4 12.1 28.9 9.2 184 14.1 2.6 2.6 0.8
2010 108 63.9 4.6 24.0 2.6 19 47.4 11.8 24.7 7.7 182 10.4 2.3 2.6 0.8
2011 110 39.1 4.7 8.5 1.6 19 15.8 8.6 5.8 3.9 183 10.4 2.3 2.9 0.9
2012 110 41.8 4.7 10.9 2.0 20 50.0 11.5 24.0 7.9 185 16.2 2.7 4.2 1.1
2013 110 42.7 4.7 11.0 1.9 20 55.0 11.4 18.5 6.0 185 21.1 3.0 3.9 0.8
2014 110 46.4 4.8 12.1 1.8 20 65.0 10.9 11.5 3.9 185 28.6 3.3 8.4 1.4

 

Pool 8
Main channel border
Secondary channel
Year
n
Frq
SE
Cov
SE
n
Frq
SE
Cov
SE
1998
 53 0.0 0.0 0.0 0.0 93 4.3 2.1 0.9 0.5
1999
 70 0.0 0.0 0.0 0.0 100 8.0 2.7 1.4 0.6
2000
 99 2.0 1.4 0.2 0.1 120 13.3 3.1 2.3 0.8
2001
 100 3.0 1.7 0.3 0.2 120 5.8 2.1 0.8 0.3
2002
 100 4.0 2.0 1.0 0.7 120 13.3 3.1 3.2 1.1
2003
 100 2.0 1.4 0.2 0.1 120 12.5 3.0 5.4 1.5
2004
 100 3.0 1.7 1.1 0.8 120 7.5 2.4 2.1 0.8
2005
 70 4.3 2.4 1.6 1.3 65 15.4 4.5 6.2 2.0
2006
 70 0.0 0.0 0.0 0.0 65 15.4 4.5 4.6 1.9
2007
 70 2.9 2.0 1.7 1.3 65 10.8 3.9 5.4 2.3
2008
 70 2.9 2.0 1.4 1.3 65 13.8 4.3 4.2 1.6
2009 70 2.9 2.0 2.0 1.5 65 10.8 3.9 7.2 2.9
2010 70 7.1 3.1 1.0 0.5 65 20.0 5.0 5.7 1.9
2011 70 1.4 1.4 0.1 0.1 65 12.3 4.1 1.2 0.4
2012 70 5.7 2.8 0.6 0.3 65 6.2 3.0 2.8 1.4
2013 70 8.6 3.4 1.4 0.8 65 20.0 5.0 3.2 1.2
2014 69 5.8 2.8 0.9 0.5 65 20.0 5.0 4.8 1.6

 

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 2.4 1.2 1.5 0.9 27 18.5 7.6 7.8 4.6 209 2.9 1.2 2.0 0.9
1999
 170 6.5 1.9 1.9 0.8 29 20.7 7.7 6.2 3.0 210 1.4 0.8 0.7 0.5
2000
 198 6.1 1.7 3.6 1.1 27 14.8 7.0 8.1 4.4 210 2.4 1.1 1.6 0.8
2001
 198 7.1 1.8 3.4 1.1 52 11.5 4.5 1.9 0.9 209 4.3 1.4 3.2 1.1
2002
 200 6.0 1.7 2.9 1.0 29 3.4 3.4 1.0 1.0 209 4.8 1.5 3.5 1.2
2003
 200 10.0 2.1 5.1 1.3 29 17.2 7.1 10.7 5.0 210 4.3 1.4 2.9 1.1
2004
 219 13.2 2.3 5.9 1.3 31 9.7 5.4 4.8 3.3 236 2.5 1.0 1.8 0.8
2005
 118 6.8 2.3 2.9 1.2 24 12.5 6.9 7.9 5.2 175 5.1 1.7 2.6 1.0
2006
 119 11.8 3.0 5.9 1.9 23 39.1 10.4 11.7 5.4 175 6.3 1.8 4.7 1.5
2007
 118 14.4 3.2 7.2 2.0 22 22.7 9.1 12.3 6.2 172 7.0 1.9 2.8 1.1
2008
 115 10.4 2.9 3.0 1.1 23 21.7 8.8 2.2 0.9 175 3.4 1.4 1.3 0.7
2009 119 17.6 3.5 10.8 2.6 24 4.2 4.2 2.9 2.9 175 5.7 1.8 3.5 1.3
2010 120 16.7 3.4 8.3 2.1 23 13.0 7.2 8.3 5.4 175 9.7 2.2 5.7 1.6
2011 120 18.3 3.5 5.3 1.5 25 12.0 6.6 5.2 3.7 175 6.3 1.8 2.0 0.8
2012 120 6.7 2.3 2.3 1.1 23 0.0 0.0 0.0 0.0 175 9.7 2.2 5.0 1.4
2013 120 15.0 3.3 4.3 1.4 25 0.0 0.0 0.0 0.0 175 6.9 1.9 2.6 0.9
2014 120 15.0 3.3 3.7 1.3 24 16.7 7.8 3.3 2.1 175 8.6 2.1 3.1 1.1

 

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 1.0 0.8
1999
 70 1.4 1.4 0.1 0.1 70 7.1 3.1 2.4 1.5
2000
 70 0.0 0.0 0.0 0.0 70 8.6 3.4 5.1 2.4
2001
 70 1.4 1.4 0.1 0.1 70 8.6 3.4 4.3 2.1
2002
 70 0.0 0.0 0.0 0.0 70 8.6 3.4 5.7 2.5
2003
 70 1.4 1.4 1.3 1.3 70 8.6 3.4 4.6 2.1
2004
 79 1.3 1.3 1.1 1.1 79 6.3 2.8 3.9 1.9
2005
 80 2.5 1.8 1.0 0.7 50 6.0 3.4 1.4 0.9
2006
 80 3.8 2.1 1.4 1.1 50 8.0 3.9 2.8 1.9
2007
 80 7.5 3.0 5.0 2.2 50 18.0 5.5 9.8 3.8
2008
 80 6.3 2.7 2.4 1.4 50 8.0 3.9 2.0 1.4
2009 77 3.9 2.2 1.4 1.2 48 10.4 4.5 5.2 2.7
2010 80 1.3 1.3 0.4 0.4 50 8.0 3.9 3.2 2.0
2011 80 0.0 0.0 0.0 0.0 50 18.0 5.5 3.8 1.7
2012 80 1.3 1.3 0.1 0.1 50 14.0 5.0 5.8 2.8
2013 79 1.3 1.3 0.1 0.1 48 10.4 4.5 5.2 2.8
2014 80 0.0 0.0 0.0 0.0 50 4.0 2.8 1.6 1.4

 

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 22.0 5.9 4.2 1.7 160 5.0 1.7 1.1 0.6 30 10.0 5.6 3.0 2.4
1999
 80 13.8 3.9 8.4 2.6 160 0.0 0.0 0.0 0.0 50 28.0 6.4 24.0 5.6
2000
 79 35.4 5.4 13.4 3.2 95 4.2 2.1 0.6 0.4 42 16.7 5.8 6.9 3.0
2001
 80 3.8 2.1 0.9 0.6 94 18.1 4.0 5.4 1.7 60 11.7 4.2 3.2 1.5
2002
 80 22.5 4.7 12.0 3.2 100 16.0 3.7 8.0 2.4 57 28.1 6.0 20.7 4.8
2003a
 80 18.8 4.4 11.9 3.3 100 36.0 4.8 20.8 3.5 60 36.7 6.3 21.7 4.5
2004
 110 27.3 4.3 16.7 3.1 132 9.1 2.5 2.6 1.0 58 32.8 6.2 20.5 4.6
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 11.1 6.2 2.6 1.9 47 0.0 0.0 0.0 0.0
1999
 80 6.3 2.7 1.6 1.1 50 0.0 0.0 0.0 0.0
2000
 39 5.1 3.6 2.6 2.3 40 0.0 0.0 0.0 0.0
2001
 40 0.0 0.0 0.0 0.0 40 2.5 2.5 1.8 1.8
2002
 40 0.0 0.0 0.0 0.0 40 0.0 0.0 0.0 0.0
2003a
 40 7.5 4.2 2.3 1.5 40 2.5 2.5 0.3 0.3
2004
 56 14.3 4.7 2.9 1.2 56 5.4 3.0 0.5 0.3
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 1.7 1.2 0.3 0.3 84 1.2 1.2 0.8 0.8
1999
 137 6.6 2.1 3.0 1.2 90 0.0 0.0 0.0 0.0
2000
 47 4.3 3.0 2.1 1.6 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 2.0 2.0 1.8 1.8 50 4.0 2.8 0.4 0.3
2003a
 50 2.0 2.0 0.2 0.2 50 0.0 0.0 0.0 0.0
2004
 69 1.4 1.4 0.1 0.1 69 10.1 3.7 2.8 1.5
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 2.3 1.1 0.2 0.1 179 3.4 1.3 1.3 0.6
–
–
–
–
–
1999
 190 3.2 1.3 2.8 1.1 188 3.7 1.4 3.4 1.2
–
–
–
–
–
2000
 100 0.0 0.0 0.0 0.0 138 2.2 1.2 0.9 0.7 57 1.8 1.8 1.6 1.6
2001
 100 0.0 0.0 0.0 0.0 129 1.6 1.1 1.4 1.0 57 0.0 0.0 0.0 0.0
2002
 100 3.0 1.7 2.1 1.2 139 2.9 1.4 2.2 1.1 59 0.0 0.0 0.0 0.0
2003b
 100 0.0 0.0 0.0 0.0 117 4.3 1.9 2.3 1.1 60 0.0 0.0 0.0 0.0
2004
 128 0.0 0.0 0.0 0.0 175 0.6 0.6 0.3 0.3 74 0.0 0.0 0.0 0.0
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
0.0
0.0
0.0
0.0
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