7^75
Efaliattom ©f Potential Use ol
VegetatiM
fm
Eroslom Abatement
Along the Great Lakes Sliwelme
by
V.L. Hall a n d J.D. Ludwig
M I S C E L L A N E O U S PAPER N O . 7-75
JUNE 1975
mm 1 ' " 11"^ > 1 V Ih .4yA p p r o v e d for p u b l i c r e l e a s e ;
disfribution unlimited.
U.S.
/ 9 *^ 7
P r e p a r e d for / /
ARMY, C O R P S O F E N G I N E E R S
R E S E A R C H C E N T E R
Kingman Building
Fort Belvoir, V a . 22060
CONTENTS Page I INTRODUCTION 7 I I PROCEDURES 8 1 . L i t e r a t u r e S e a r c h 8 2. F i e l d S u r v e y 9 I I FIELD OBSERVATIONS 9 1 . Lake S u p e r i o r 9 2. Lake M i c h i g a n 13 3. Lake H u r o n . •, 18 4. Lake E r i e 2 1 5. Lake O n t a r i o 2 1 IV RESULTS AND DISCUSSION 24
1 . L i t e r a t u r e Review 24 2. F i e l d S u r v e y 24 V SUMMARY AND CONCLUSIONS .32
LITERATURE CITED 34 TABLES 1 S c o r e c a r d i n d e x i n g e r o s i o n c o n t r o l p o t e n t i a l o f p l a n t s p e c i e s 10 2 S a m p l i n g p o i n t s a l o n g t h e G r e a t Lakes s h o r e l i n e 12 3 C h a r a c t e r i s t i c s o f p l a n t s i d e n t i f i e d d u r i n g l i t e r a t u r e r e v i e w 26 4 C h a r a c t e r i s t i c s o f p l a n t s i d e n t i f i e d d u r i n g f i e l d s u r v e y 28 5 P l a n t s p e c i e s w i t h good t o e x c e l l e n t p o t e n t i a l f o r e r o s i o n a b a t e m e n t 29 FIGURES 1 L o c a t i o n s o f s a m p l i n g p o i n t s a l o n g t h e G r e a t Lakes 1 1 2 Sand b l o w o u t caused b y w i n d e r o s i o n 14 3 A s e c o n d a r y c o l o n i z e r , sand c h e r r y , i n v a d i n g a s a n d dune 15 CONTENTS FIGURES - C o n t i n u e d • ^^^^
4 Bank e r o s i o n c a u s e d b y seepage h i g h above t h e w a t e r l e v e l . . - 16 5 Wave s c o u r i n g causes u n d e r c u t t i n g a n d bank r e c e s s i o n ^
w i t h l o s s o f v e g e t a t i o n • • 6 Lake M i c h i g a n b a n k e r o s i o n c a u s e d b y seepage t h r o u g h ^ s a n d and g r a v e l l a y e r s 7 A s e a w a l l a t K e n i l w o r t h , I l l i n o i s h a s s u c c e s s f u l l y s t a b i l i z e d t h e bank 8 G e n t l y s l o p i n g s h o r e l i n e (Lake M i c h i g a n ! 22 9 P r o t e c t i v e s t r u c t u r e c r e a t i n g p o o l f a v o r a b l e f o r g r o w t h o f r e e d 10 Landscaped b e a c h a r e a a n d p a r k i n g l o t d e v e l o p e d b y _ . 25 r e f o r m i n g a h i g h e r o d i n g sandbank - • - • 11 R e f o r m a t i o n o f r o u g h b a n k a n d l a n d s c a p i n g o f shoT^eline
EVALUATION OF POTENTIAL USE OF VEGETATION FOR EROSION ABATEMENT ALONG THE GREAT LAKES SHORELINE
b y
Y.L. Bolt and J.D. Ludwig I. INTRODUCTION The p r e s e n t p h y s i c a l c h a r a c t e r i s t i c s o f t h e G r e a t Lakes s h o r e s i n t h e U n i t e d S t a t e s r e s u l t e d f r o m n a t u r a l changes i n t h e G r e a t L a k e s r e g i o n s i n c e t h e g l a c i a l r e c e s s i o n a n d f r o m t h e man-induced d e v e l o p m e n t s o f r e c e n t y e a r s . The s h o r e v a r i e s f r o m h i g h c l a y , s h a l e , a n d r o c k b l u f f s , t o l o w e r s h o r e s o f r o c k , s a n d y b e a c h , a n d marsh. E x c e p t w h e r e b e d r o c k i s a l r e a d y exposed o r p r o t e c t i v e w o r k s h a v e been c o n s t r u c t e d , t h e s h o r e s o f t h e G r e a t Lakes a r e b e i n g a l t e r e d b y w a t e r and w i n d e r o s i o n . Wave e r o s i o n i s t h e most s e v e r e t y p e o f e r o s i o n o c c u r r i n g a l o n g t h e open s h o r e s o f t h e G r e a t L a k e s . Damage f r o m wave e r o s i o n has b e e n more p r o n o u n c e d s i n c e l a k e l e v e l s h a v e r i s e n , t h e r e s u l t o f r e c e n t i n c r e a s e s i n r a i n f a l l o v e r t h e G r e a t Lakes b a s i n . The a v e r a g e a n n u a l r a i n f a l l f r o m 1900 t o 1972 f o r t h e b a s i n was a b o u t 32 i n c h e s ; s i n c e 1964, howe v howe r , t h howe a n n u a l r a i n f a l l h a s b howe howe n a b o v howe t h a t 7 2 y howe a r f i g u r howe ( I n t howe r -n a t i o -n a l G r e a t Lakes L e v e l s B o a r d , 1973, 1 9 7 4 ) . S u r f a c e r u n o f f , t h e s e c o n d m o s t p r e v a l e n t t y p e o f e r o s i o n a l o n g t h e G r e a t Lakes s h o r e s , i s most d e s t r u c t i v e o n s t e e p , u n p r o t e c t e d s l o p e s . I f p r o t e c t i o n i s i n a d e q u a t e , g u l l i e s f o r m r a p i d l y . A r e l a t e d p r o b l e m , seepage, causes s l u m p i n g , w h i c h i n c r e a s e s t h e e r o s i o n r a t e and p r o b a b i l i t y o f l a n d s l i d e s .
O t h e r a g e n t s o f l e s s e r c o n c e r n c a u s i n g s h o r e l i n e e r o s i o n a r e f r e e z i n g a n d t h a w i n g a n d t h e a c t i o n o f f l o a t i n g i c e . F r e e z i n g i n -c r e a s e s t h e v o l u m e o f w a t e r a n d t h a w i n g r e d u -c e s t h e v o l m e ; - t h e expan-s i o n - c o n t r a c t i o n p r o c e expan-s expan-s can move expan-s o i l o r r o c k expan-s u f f i c i e n t l y t o cauexpan-se l a n d s l i d e s o r r o c k f a l l s . I n a d d i t i o n t o t h e d i s p l a c e m e n t f r o m f r e e z i n g , t h a w i n g may a l s o cause an u n s t a b l e l a y e r t o f o r m b e t w e e n t h e i c e a n d s u b s t r a t e , t h u s i n c r e a s i n g t h e t e n d e n c y t o w a r d bank f a i l u r e .
F l o a t i n g i c e has a v a r i a b l e e f f e c t o n s h o r e e r o s i o n . D r i v e n a s h o r e b y s t r o n g w i n d s , i t c a n cause e x t r e m e l a n d s c o u r i n g . On t h e o t h e r h a n d , i c e may move o n t o s h o r e a n d f o r m a p r o t e c t i v e b a r r i e r a g a i n s t wave a c t i o n t h a t w o u l d o t h e r w i s e e r o d e t h e s h o r e .
Wind e r o s i o n , n o r m a l l y a d r y - w e a t h e r phenomenon, o c c u r s a r o i m d G r e a t Lakes dune a r e a s t h a t a r e d r o u g h t y and b a r r e n . Wind i s espe-c i a l l y d e s t r u espe-c t i v e i n dune a r e a s , b l o w i n g sand i n l a n d . The d e p o s i t e d sand may b u r y e s t a b l i s h e d v e g e t a t i o n a n d p e r h a p s d e v e l o p a new dune a r e a .
E r o s i o n a l p r o b l e m s and damages i n c l u d e l o s s o£ l a n d , i m p e r i l m e n t t o r o a d w a y s , l o s s o f r e c r e a t i o n a l b e a c h , l o s s o f access t o t h e l a k e s , and s t r u c t u r a l damage t o d w e l l i n g s , b o a t h o u s e s , d o c k s , a n d s t a i r w a y s ! Some s h o r e l i n e c o n d i t i o n s a l o n g t h e G r e a t Lakes a r e d i f f i c u l t t o a l t e r t o c o n t r o l e r o s i o n , p a r t i c u l a r l y i n a r e a s where t h e r e i s no beach o r where t h e w a t e r i n t e r f a c e s i m m e d i a t e l y w i t h s t e e p b l u f f s . However, t h e r e a r e numerous a r e a s where e r o s i o n c a n be a b a t e d b y a t t e n u a t i n g wave a c t i o n w i t h m e c h a n i c a l b a r r i e r s and t h e n u s i n g t e r r e s t r i a l a n d a q u a t i c v e g e t a t i o n t o p r o t e c t t h e s h o r e a g a i n s t t h e r e d u c e d wave a c t i o n and a g a i n s t s u r f a c e r u n o f f . T h e r e a r e t h r e e t y p e s o f t e r r e s t r i a l p l a n t s t h a t c a n be u s e d t o a b a t e e r o s i o n : ( a ] p i o n e e r p l a n t s , t h e s p e c i e s t o f i r s t become e s t a b l i s h e d on new s u b s t r a t e s ; (b) s e c o n d a r y p l a n t s , t h e s p e c i e s t o f i r s t i n v a d e e d a p h i c a l l y s t a b l e a r e a s c o l o n i z e d b y t h e p i o n e e r p l a n t s ; and ( c ) t e r t i a r y p l a n t s , t h e s p e c i e s p o o r l y a d a p t e d t o dynamic c o n d i t i o n s and r e q u i r i n g a r e a s p r e v i o u s l y s t a b i l i z e d by p i o n e e r and s e c o n d a r y s p e c i e s . Most s p e c i e s u s e d i n t e r r e s t r i a l p l a n t i n g o p e r a t i o n s a r e t h e p i o -n e e r t y p e . The p i o -n e e r i -n i t i a t e s a developme-nt seque-nce (Cowles, 1899; Hack, 1 9 4 1 ) . I t s t a b i l i z e s t h e s u r f a c e , p r o v i d e s l o d g i n g f o r w i n d b o r n e d i s s e m i n u l e s , s h i e l d s s e e d l i n g s f r o m s u n and w i n d , and p r e p a r e s t h e way f o r n a t u r a l i n v a s i o n o f o t h e r p l a n t t y p e s CDaubenmire, 1 9 6 8 ) .
E s t a b l i s h m e n t o f h y d r o p h y t e s (submergent o r emergent p l a n t s ) i s v e r y d i f f i c u l t . They a r e h i g h l y r e s t r i c t e d b y c u r r e n t s a n d w a t e r l e v e l f l u c t u a t i o n s . Emergent h y d r o p h y t e s a r e l i m i t e d t o l o w - e n e r g y s h o r e s , where t h e y m o d i f y l e s s f o r c e f u l waves; submergent a q u a t i c p l a n t s e s t a b -l i s h i n even more p r o t e c t e d a r e a s . The r e s t r i c t i o n o f submergent s p e c i e s t o q u i e t w a t e r s l i m i t s t h e i r p h y t o g e o g r a p h i c a l d i s t r i b u t i o n , and t h e i r v u l n e r a b i l i t y t o s t r o n g wave f o r c e s p r o h i b i t s them f r o m n a t u -r a l l y c o l o n i z i n g t h e wave-swept l i t t o -r a l zones o f l a k e s . The m a i n p u r p o s e o f t h i s i n v e s t i g a t i o n was t o d e t e r m i n e i f t e r r e s -t r i a l a n d h y d r o p h y -t i c p l a n -t s , e i -t h e r a l o n e o r i n c o m b i n a -t i o n w i -t h s t r u c t u r e s , c a n be u s e d t o a t t e n u a t e wave energy i m m e d i a t e l y o f f s h o r e and t o s t a b i l i z e t h e a r e a s a d j a c e n t t o t h e w a t e r l i n e , t h e r e b y r e d u c i n g t h e e r o s i o n r a t e a l o n g t h e Grea t Lakes s h o r e s . I I . PROCEDURES The s t u d y was c o n d u c t e d i n t w o p h a s e s , a l i t e r a t u r e s e a r c h a n d a f i e l d s u r v e y . I n b o t h p a r t s o f t h e s t u d y , t h e emphasis was on v e g e t a -t i o n endemic -t o -t h e G r e a -t Lakes a r e a , because -t h e s e p l a n -t s a r e e x p e c -t e d t o be w e l l a d a p t e d t o t h e p r e s e n t e n v i r o n m e n t a l , e d a p h i c , and c l i m a t o -l o g i c a -l s t r e s s e s . 1. L i t e r a t u r e S e a r c h . The l i t e r a t u r e was r e v i e w e d f o r p e r t i n e n t i n f o r m a t i o n o n p l a n t s u s e f u l f o r r e d u c i n g s h o r e e r o s i o n . Based on i n f o r m a t i o n f r o m t h e s e s o u r c e s p l a n t s were e v a l u a t e d f o r t h e i r p o t e n t i a l a d a p t a b i l i t y t o a b a t e e r o s i o n on t h e Great Lakes s h o r e l i n e . P l a n t s were c l a s s i f i e d b y t h e i r a b i l i t y t o i n v a d e and become e s t a b l i s h e d as p i o n e e r , s e c o n d a r y , o r t e r t i a r y s p e c i e s .
F e d e r a l and S t a t e a g e n c i e s , u n i v e r s i t i e s , and p r i v a t e i n d u s t r i e s p r o v i d e d t o p o g r a p h i c maps o f t h e Great Lakes s h o r e l i n e and s e v e r a l r e p o r t s r e l a t e d t o e r o s i o n p r o b l e m s and c o n t r o l s . I n t e r v i e w s were h e l d w i t h p e r s o n n e l k n o w l e d g e a b l e about t h e Great Lakes a r e a o r e r o s i o n c o n t r o l methods.
D u r i n g t h e l i t e r a t u r e s u r v e y , i n f o r m a t i o n on u s e o f s t r u c t u r e s and s h o r e l i n e m o d i f i c a t i o n s was c o l l e c t e d and used t o f o r m b r o a d g u i d e l i n e s f o r e v a l u a t i n g how v a r i o u s s t r u c t u r a l a n d s h o r e l i n e m o d i f i c a t i o n s m i g h t be used w i t h v e g e t a t i o n t o d e c r e a s e e r o s i o n r a t e s . 2. F i e l d Survey. A s c o r e c a r d f a s h i o n e d a f t e r P a r k e r and Woodhead's (1944) s c o r e c a r d was d e v e l o p e d ( T a b l e 1) f o r e v a l u a t i n g t h e e r o s i o n c o n t r o l p o t e n t i a l o f p l a n t s f o u n d a t t h e s i t e . The c a r d was d e s i g n e d t o i n d e x r e p r o d u c t i v e p o t e n t i a l , d e n s i t y , c o m p o s i t i o n , o r g a n i c l i t t e r a c c u m u l a t i o n , s o i l d e p o s i t i o n and r e m o v a l , g u l l y f o r m a t i o n , s l o p e a n g l e , and e v i d e n c e o f wave a c t i o n . The c a r d a l l o w e d f o r e v a l u a t i o n o f s p e c i e s t o be p e r f o r m e d in situ. S i n c e t h e c a r d i n c l u d e s t w o e d a p h i c c a t e g o r i e s n o t a p p l i c a b l e t o a q u a t i c p l a n t s , t h e i n v e s t i g a t o r s w e i g h t e d t h e e v a l u a t i o n s o f t h e r e m a i n i n g p a r a m e t e r s t o compensate f o r t h e d i f f e r e n c e . The b e s t e x p r e s s i o n o f each c a t e g o r y r e c e i v e d t h e l o w e s t n m e r i c a l v a l u e ; p l a n t s w i t h an i n d e x l e s s t h a n 31 c l a s s i f y as p o t e n t i a l l y e f f e c t i v e e r o s i o n abatement s p e c i e s . Reconnaissance o f t h e Lake S u p e r i o r s h o r e i n c l u d e d t h e S t a t e s o f W i s c o n s i n and M i c h i g a n ; Lake M i c h i g a n s h o r e s were s u r v e y e d n e a r Kewaunee, W i s c o n s i n , a n d f r o m M i l w a u k e e , W i s c o n s i n , t o Muskegon, M i c h i g a n . The n o r t h and s o u t h s h o r e o f Lake Huron were s u r v e y e d . The Lake E r i e s h o r e l i n e f r o m D e t r o i t , M i c h i g a n , t o B u f f a l o , New York,was i n s p e c t e d . The Lake O n t a r i o s h o r e l i n e was s u r v e y e d f r o m Youngstown t o R o c h e s t e r , New Y o r k , w h e r e v e r t h e r e was access t o t h e l a k e . S a m p l i n g p o i n t s ( F i g . 1) f o r each o f t h e l a k e s a r e l o c a t e d b y c o u n t y . S t a t e , and v i c i n i t y i n T a b l e 2. Because p r i v a t e o w n e r s h i p a l o n g t h e Lake M i c h i g a n s h o r e l i m i t e d a c c e s s , t h e number o f s u r v e y p o i n t s t h e r e was r e d u c e d . I I I . FIELD OBSERVATIONS 1. Lake S u p e r i o r . Most W i s c o n s i n s h o r e s e a s t o f S u p e r i o r t o C o r n u c o p i a , p a r t i c u l a r l y a l o n g t h e r e d c l a y b l u f f s , a r e s u b j e c t t o e r o d i n g r u n o f f f r o m u p l a n d a r e a s u n d e r c u t t i n g b y wave a c t i o n , and c l a y bank s l o u g h i n g caused b y seepage.
T a b l e 1. S c o r e c a r d i n d e x i n g e r o s i o n c o n t r o l p o t e n t i a l o f p l a n t s p e c i e s
Slto location_ Otma
S p e Q l 6 a _
Conaon Hmo
PUNT rJDICA.TORS! Baaed on c o l o r , h o l ^ h t md voluno, ociparo v i t h n o d a r s t a l y p r o U o t a d t r a a s .
KUnts robust, w i t h h e a l t h y , dirk grean c o l o r «ld e x t r e n o l y nunarous loaves, seed s t a l k s long and nunorous, f a v o r no dead p l a n t s . Roproduotion
p l e n t i f u l i n good years..,,, • 1 Plants as above w i t h long seed s t a l k s . Raproductlon sparco except I n
oxtrorjoly good years, Occasloml spots I n tho v o c o t a t l v o typo i n f a i r o r poor c o n d i t i o n t(««.i.>t>.« •«•«•*>i ••(«•• •*« 3
Plants moderately h e a l t h y w i t h aoderata l e n g t h seed s t a l k s 5
Plants woik, nay be p a l e , a l o k l y c o l o r . Seed s t a l k s few and extremely s h o r t .
Seedlings r a r o w i t h death loss g r o a t , 7 Plants w i t h new b a s U o r t e r m i n a l growth and p l e n t i f u l young p l a n t s , . , , * . , 1
Plants hodged., 2
Plants A s s u a a hedged appearance 3
Kany p l a n t s dead o r w i t h numerous dead branches. I n f e r i o r species present 5 Density S i t c a l l a n t 1 Good 2 F«ir 3 Poor
Ccrjpositlon Sxoellent 1 Good 2 P a i r 3 Poor k Annual grasses and/or woody spooies
Sparco o r l a c k i n g 0 Abundant 1 Voiy abundant 2
Sand and s o i l d e p o s i t i o n (wind)
Ko d r i f t * 0
S U g h t d r i f t 1 Moderate d r i f t * * 3
Heavy d r i f t * 5 ExcasslvB d r i f t (blown sand and dunes) « ?
Sand and s o i l ronoval (water and wind)
A U s o i l l a y e r s o r h o r l i o n s i n U c t and w e l l covered w i t h p l a n t d e b r i s ,
no apparent sheet erosion , • ^ A l l s o i l l a y e r s i n t a c t b u t s o i l moveeiont can bo detected try occasional
rainlaturo a l l u v i a l f a n s , o c c a s i o n a l exposed pebbles and r o c k s . , , , 1 Upper s o i l h o r i z o n boginnlng t o break up w i t h nuaorous n i n U t u r e
a l l u v i a l fans, e r o s i o n a l paveaont forming from exposed pebbles and rocks ••• > 3
Upper s o i l h o r i z o n r a p i d l y being roaoved, w i t h spots o f raw s u b s o i l
exposed, e r o s i o n a l pavontxnt developed • 5
Upper s o i l h o r i z o n l a r g e l y renoved, e r o s i o n a l paveaont axcassive,
s o i l s g e n e r a l l y hard and coapact, raw s u b s o i l exposed 7 G u l l y f o r m a t i o n
No g u l U e s Q Occasional s m a l l ahallow g u l l U s b u t w e l l healed w i t h v e g e t a t i o n . , , . , I
Occasional shallow g u l l i e s , , . , . , , *••«*• *44*« 2
Occasional deop g;ullia3 » **•*•*•>< > 3
Frequent g u l l i e s , ahallow *...*.... *. 5
Frequent deep V- o r U- shaped g u U l e s 7 Slope angle
0 - 2 0 i . , . ,
20-35^... 35-60^
60% and above.
s o n . INDICATORS I
Organic l i t t e r on s o i l surface between p l a n t s
Very abundant 1 Comon 2 Scare 3 Hone,« k Evidence o f wave a c t i o n Nornal o r below t
IHTiRPRETATIOJI OF TOTAL SCORE
E x c e l l e n t . . Good , .7-18 ,.19-30 Abundant . . . 2 Excessive ,,.3 O n s a t l s f a c t o r / o r f a i r 31-'*2 Poor ^y-^^ Other CoOTentsi ( A f t e r P a r k e r and Woodhead, 1944) F i g u r e 1. L o c a t i o n s o f s a m p l i n g p o i n t s a l o n g t h e Great Lakes.
T a b l e 2. Sampling p o i n t s along the Croat U k o ï 3hor<-linn Sampling
Point County/State
LttVc Sup o r l o r "•
1 B a y f i e l d , W i s c o n s i n West o f F i s h Crock mouth on S t a t e Route 13 2 B a y f i e l d , W i s c o n s i n 2.5 n i l o s west o f P o r t Wing on S t a t e Route 13 3
4
B a y f i e l d , H l s c o n s i n B a y f i e l d , Wisconsin
North o f Port King and o a s t o f l i g h t h o u s e 'Herbster
s B a y f i e l d , Wisconsin Cornucopia 6 Marquotto, Michigan Buckroc
7 Marquette. Michigan 32 m i l e s west o f Munising on S t a t e Route 28 8 A l g e r . Michlfian l l m i l e s west o f Munising on S t a t e Route 23 S A l g e r , Michigan Grand Marais S t a t e Park
10 Chippewa. Michlean W h i t e f i s h P o i n t U k e Mle i i j a n
n Kewaunee, Wisconsin Kewaunee
12 Lake, a U n o l s I l l i n o i s Bench S t a t e Park X3 Cook, I l l i n o i s Cloncoc
14 Cook, I l l i n o i s Kenilworth 15 P o r t e r , I n d i a n a P o r t e r 16 B e r r i e n , Michigan New B u f f a l o 17 B e r r i e n . Michigan Union P i e r 18 B e r r i e n , Michigan Warren [Junes S t a t e Park 19 B e r r i e n . Michigan St, Joseph 30
21
Van Burcn, Michigan Enoaet. Michican
4.S n i l e s s o u t h o f Grand Haven. Van Buren S t a t e Park C e c i l Bay
Lake Huro
22 Mackinac, M i c h i j a n 38 m i l e s e a s t o f S t a t e Route 134, 1-75 I n t e r c h a n g e on S t a t e Route 134
23 Mackinac. Michigan 3.4 m i l e s e a s t o f S t a t e Route 134. 1-75 I n t e r c h a n g e on S t a t e Route 134
24 Presque I s l e . Michigan 6.7 m i l e s n o r t h w e s t o f Huron Beach on U.S. 23 2S P r c s q u c I s l e , Michigan S.g m i l e s northwest o f Huron Beach on U.S. 23 26 Presque I s l e , Michigan 2.B m l l o s n o r t h w e s t o f Huron Beach on U.S, 23 U k e E r i c
27 Monroe. Michigan S t e r l i n g S t a t e Park 28 Ottawa. Ohio Crane Creek S t a t e Park
29 E r i e , Ohio 2.7 m i l e s west o f j u n c t i o n o f S t a t e Route 60 and S t a t e Routes 2 and 6 i n V e r m i l i o n
30 E r i e . Ohio 1 m i l e west o f j u n c t i o n o f Static Route 60 and S t a t e Routes 2 and 6 in V e r m i l i o n
31 L o r a i n , Ohio
i'^Lo'^^^^ °^ j u n c t i o n o f S t a t e Route 611 and * 32 L o r a i n , Ohio 0 . 8 ^ i l e west o f j u n c t i o n o f S t a t e Route 6 and 57
33 Cuyahoga, Ohio Huntington Park. C l e v e l a n d 34
35
U k e . Ohio U k e , Ohio
Headlands S t a t e Beach Park, F a l r p o r t Harbor Madison-on-the-Uke
36 A s h t a b u l a , Ohio Ccncva-on-the-Uke 37 A a h t a b u l * , Ohio A s h t a b u l a 38 A s h t a b u l a , Ohio Conncaut
39 E r i e . P e n n s y l v a n i a Prosquo I s l e S t a t e Park
40 E r i e , P e n n s y l v a n i a F r c c p o r t Yacht Club j u n c t i o n o f S t a t e Routes 5 and 89 41 Chautauqua. New York R i p l e y
42 Chautauqua, New York Barcelona 43 Chautauqua, New York U k e E r i e S t a t e Park 44 Chautauqua, New York Dunkirk 4S E r i e , New York Evangola S t a t e Park U k e O n t a r i O
46 N i a g a r a . New York Cooildgo Beach 47 N i a g a r a , New York R o o s e v e l t Beach 48 N i a g a r a , New York Wilson 49 N i a g a r a , New York U k o v i e w SO O r l e a n s . New York Shadlgee S I O r l e a n s . New York L a k e s i d e
52 Monroe. New York Homlin Beach S t a t e Park
Wave a c t i o n and e r o s i o n a p p e a r e d m i n i m a l a l o n g t h e M i c h i g a n s h o r e between M a r q u e t t e and B i g Bay. The c o a s t l i n e was f o r e s t e d , w i t h a n a r r o w b e a c h . G e n e r a l l y , f o r e s t s e x t e n d e d t o t h e h i g h w a t e r l i n e w i t h no e v i d e n c e o f s e v e r e s h o r e e r o s i o n .
Sand dunes o f t h e Grand S a b l e Banks n e a r Grand M a r a i s , M i c h i g a n , are s u b j e c t t o b l o w o u t s ( F i g . 2) and w i n d e r o s i o n . The s h o r e a t
W h i t e f i s h P o i n t , M i c h i g a n , i s r e l a t i v e l y f l a t and i s e r o d i n g . Rock was exposed i n many a r e a s , b u t where v e g e t a t i o n e x i s t e d , i t r e t a i n e d s m a l l mounds o f sand; t h i s a r e a showed some o f t h e most s u c c e s s f u l examples o f sand r e t e n t i o n by v e g e t a t i o n .
No emergent h y d r o p h y t e s were o b s e r v e d on t h e Lake S u p e r i o r s h o r e s . E x t e n s i v e beach a r e a s n o r t h o f P o r t Wing, W i s c o n s i n , a r e s t a b i l i z e d by t h e t e r r e s t r i a l c o d o m i n a n t s beach-pea (Lathyrus maritimus) and w i l d r y e (Elymus motlis). A l o w t o p o g r a p h i c r e l i e f enhanced l a n d s t a b i l i z a
t i o n b y b o t h r h i z o r a a t o u s p e r e n n i a l s . Dense r h i z o m a t o u s mats o f b l u e -j o i n t (CaZamagrostis canadensis), p r a i r i e s a n d r e e d (Catamovilfa
longi-foVia), brome g r a s s (Bromus haZmii), and r u s h (Junous baltious) were
o b s e r v e d a t C o r n u c o p i a , W i s c o n s i n . These h e t e r o g e n e o u s s t a n d s c l o s e t o t h e wave-shore i n t e r f a c e p r o v i d e d e x c e l l e n t c o n t r o l a g a i n s t s u r f a c e r u n o f f .
E l e v e n m i l e s w e s t o f M u n i s i n g , M i c h i g a n , i s a sandy s h o r e s t a b i l -i z e d b y w -i l d r y e and sand c h e r r y (Prunus -pum-ila). I n v a s -i o n o f t h e s e c o n d a r y c o l o n i z e r , sand c h e r r y , i s s u c c e s s f u l l y s t a b i l i z i n g t h e s o i l
( F i g . 3 ) . A c t i v e sand dune b l o w o u t s , s t a b l e sand dunes, and s u c c e s s i o n a l p l a n t e s t a b l i s h m e n t were f o u n d a t Grand M a r a i s S t a t e P a r k , M i c h i g a n . P i o n e e r sand s t a b i l i z e r was a g a i n w i l d r y e . The l e e s i d e o f a c t i v e dunes was c o l o n i z e d b y t h e h e r b a c e o u s p i o n e e r t a n s y (Tanaoetum huronense) and t h e s e c o n d a r y c o l o n i z e r s sand c h e r r y and h e a r t - l e a v e d w i l l o w (Salix
aordata). T e r t i a r y s p e c i e s were l i m i t e d t o b a l s a m p o p l a r (Populus balsamifera). A t W h i t e f i s h P o i n t , M i c h i g a n , a b r a s i o n b y b l o w i n g sand
l i m i t e d v e g e t a t i v e v i t a l i t y and d i v e r s i t y , a l t h o u g h t h e l o w - h a b i t f a l s e h e a t h e r (Hudsonia tomentosa), a l o n g w i t h s c o u r i n g r u s h (Equisetum
hyemale) and w i l d r y e , were v i g o r o u s enough t o impede t h e w i n d and
accum-u l a t e a p p r e c i a b l e sand moaccum-unds.
Some bank e r o s i o n a l o n g t h e Lake S u p e r i o r s h o r e was caused b y seep-age ( F i g . 4) and wave s c o u r i n g ( F i g . 5 ] . O n l y one s t r u c t u r e was n o t e d , r i p r a p t o a b a t e bank e r o s i o n n e a r t h e S t a t e h i g h w a y a t H e r b s t e r , Wiscon-s i n . The t r e a t m e n t a p p e a r e d Wiscon-s u c c e Wiscon-s Wiscon-s f u l ; t h e bank waWiscon-s Wiscon-s t a b i l i z e d , w i t h v e g e t a t i o n w e l l e s t a b l i s h e d between t h e r i p r a p and r o a d t o p r e v e n t e r o s i o n due t o s u r f a c e r u n o f f .
2. Lake M i c h i g a n .
Kewaunee County s h o r e s s o u t h o f Kewaunee, W i s c o n s i n , w e r e h i g h , n e a r - v e r t i c a l b l u f f s o f g l a c i a l t i l l w i t h exposed sand and g r a v e l l e n s e s . D u r i n g w e t p e r i o d s , t h e l e n s e s become w a t e r - s a t u r a t e d and seepage a l o n g
t h e b l u f f causes s l u m p i n g o f t h e s o i l a n d , a t t i m e s , l a r g e l a n d s l i d e s . Shore c o n d i t i o n s o f Lake M i c h i g a n f r o m M i l w a u k e e , W i s c o n s i n , t o Muskegon, M i c h i g a n , v a r i e d f r o m s l o p i n g beaches t o s e v e r e l y e r o d i n g b l u f f s . The s h o r e l i n e o f C e c i l Bay was n o t s e v e r e l y e r o d i n g ; t h e b a y f o r m e d a p r o t e c t e d a r e a w i t h a r e l a t i v e l y f l a t b o t t o m f o r a c o n s i d e r -a b l e d i s t -a n c e f r o m s h o r e .
Two emergent h y d r o p h y t e s , g r e a t b u l r u s h (Scirpus aautus) a n d s p i k e r u s h (Eleooharvs palustris) were o b s e r v e d a t C e c i l Bay, M i c h i g a n .
V i g o r o u s s t a n d s o f w i l d r y e were p r e s e n t a t t h e p u b l i c b e a c h a t Kewaunee, W i s c o n s i n , d e s p i t e p u b l i c l a n d u s e p r e s s u r e s . A t I l l i n o i s Beach S t a t e P a r k , d i v e r s e p l a n t s p e c i e s enhanced s a n d a c c u m u l a t i o n . The p i o n e e r w i l d r y e and t h e s e c o n d a r y i n v a d e r s , c r e e p i n g c e d a r
(Juniperus hoT-izontalis), f a l s e Solomon's s e a l (Smilaeina stellata),
s a n d b a r - w i l l o w (Salix inteTVOT), p e p p e r - g r a s s (Lepidvim vi-rgi-niovm), w i l d r o s e (Rosa hlanda), f o r e s t - g r a p e (Vitis riparia), sand c h e r r y , and b e a r b e r r y (Arotostaphylos uva-ursi) were w e l l e s t a b l i s h e d . W i l d r y e , an e x c e l l e n t sand b i n d i n g g r a s s , was p r e s e n t a l s o a t P o r t e r ,
I n d i a n a .
S t e e p , u n s t a b l e sandy b l u f f s a r e a p r o b l e m a t New B u f f a l o , M i c h i g a n , b u t t h e sand c h e r r y e s t a b l i s h e d o n t h e more g e n t l e cap has i n c r e a s e d s l o p e s t a b i l i t y , t h e r e b y r e t a r d i n g t h e s l o u g h i n g p r o c e s s . H i g h w a t e r t o e l i n e s were s t a b i l i z e d b y f o r e s t - g r a p e and r e d o s i e r dogwood (Comus
stoZonifera) a t U n i o n P i e r , M i c h i g a n . S t a b i l i z e d dunes w e r e n o t e d a t
Warren Dunes S t a t e P a r k , M i c h i g a n . T h e r e , t h e d o m i n a n t r h i z o m a t o u s g r a s s , p r a i r i e s a n d r e e d , p r o v i d e d a w i n d i m p e d i m e n t r e s u l t i n g i n sand a c c i a m u l a t i o n and dune s t a b i l i z a t i o n .
The S o i l C o n s e r v a t i o n S e r v i c e a t Kewaunee, W i s c o n s i n , has s u c c e s s -f u l l y s t a b i l i z e d s h o r e s b y d e w a t e r i n g t h e g l a c i a l t i l l , s l o p i n g t h e f a c e o f t h e b l u f f s , a n d s e e d i n g t h e r e s h a p e d s l o p e s ( F i g . 6 ) . I n t h i s case, d e w a t e r i n g i s t h e k e y f a c t o r and i s e s s e n t i a l t o c o n t r o l e r o s i o n caused b y seepage.
A t t h e K e n i l w o r t h , I l l i n o i s , P u b l i c Water Works, a c o n c r e t e s e a w a l l and g r o i n have been b u i l t ( F i g . 7 ) . A p r i v a t e r e s i d e n t i a l b e a c h f r o n t e d t h e s e a w a l l , b u t t h e r e c e n t r i s e i n w a t e r l e v e l has r e d u c e d t h e beach t o a s m a l l a r e a a d j a c e n t t o t h e g r o i n . T h i s s e a w a l l has s u c c e s s -f u l l y c o n t r o l l e d bank e r o s i o n .
A b o u t 4.5 m i l e s s o u t h o f Grand Haven, M i c h i g a n , a h i g h sandbank o v e r l i e s a f i r m c l a y base; r a i n f a l l r a p i d l y e r o d e d t h e u n p r o t e c t e d sand, and g u l l i e s d e v e l o p e d i n t h e s h o r e . P u b l i c access w i l l i n f l u e n c e what t y p e o f v e g e t a t i o n i s used h e r e . 3. Lake Huron . The n o r t h e r n s h o r e s o f Lake H u r o n , f r o m i t s j u n c t i o n w i t h I n t e r -s t a t e Highway 75 t o De Tour V i l l a g e , M i c h i g a n , ( a n d a d j a c e n t t o S t a t e IB to C • X O 'H . a X (P aj +J 13 -H ca CI 3 t/) ^ O 3 0) Q ai > O oJ f^ • C M / — . O 4-1 -H TJ m m C <D O CÖ I <D T3 C ^ .X
rt
.-I C t/) .H rt + j OO ,-1 c d rt ta O .H •Hrt
+J r-l O bo •H O rt X rt <u c —3 t/l .H > rt U 0) O N bo - H <Drt
-o •4-1 ~ O bo C C 3 •H a, rt X u 3 O (U u - -H ^ > CD U > 0) O w rt c ^ O + J Ort
•H > o c 5Highway 1 3 4 ) , i s about 43 m i l e s l o n g . The s h o r e c o n s i s t s o f l o w p l a i n s and some o u t c r o p s o f l i m e s t o n e and d o l o m i t e . None o f t h e s i t e s
i n s p e c t e d had s e v e r e l y e r o d i n g s h o r e l i n e s .
A s e c o n d s u r v e y was made a l o n g U.S. Highway 23 f r o m Mackinaw C i t y , M i c h i g a n , t o Hammond Bay, where t h e s h o r e i s p o t e n t i a l l y e r o d i b l e even t h o u g h s t o n y . A l t h o u g h t h e banks appeared t o be e a s i l y e r o d i b l e , t h e r e was l i t t l e e v i d e n c e o f s e v e r e e r o s i o n , and g r a s s e s and b r o a d l e a v e d p l a n t s were o b s e r v e d i n t h e sandy r e a c h e s . A g e n t l y s l o p i n g s h o r e 3.5 m i l e s e a s t o f S t a t e Route 134 and t h e I n t e r s t a t e 75 i n t e r c h a n g e p r o v i d e d s u i t a b l e h a b i t a t f o r b l u e j o i n t , g r e a t b u l r u s h , and r u s h ( F i g . 8) . A l t h o u g h b l u e j o i n t and r u s h a r e f l o o d - t o l e r a n t , t h e y a r e n o t i m p o r t a n t s p e c i e s f o r wave a t t e n u a t i o n . A b o u t 38 m i l e s e a s t o f t h e S t a t e Route 1 3 4 I n t e r s t a t e 75 i n t e r -change, p i o n e e r , s e c o n d a r y , and t e r t i a r y t e r r e s t r i a l s p e c i e s were obs e r v e d . R h i z o m a t o u obs , h e r b a c e o u obs p i o n e e r obs i n c l u d e d w i l d r y e a n d b l u e -j o i n t . S e c o n d a r y s p e c i e s i n c l u d e d c r e e p i n g c e d a r , f a l s e Solomon's s e a l , sand c h e r r y , and b e a r b e r r y . The i n v a d i n g a r b o r e s c e n t t e r t i a r y s p e c i e s was b a l s a m f i r (Abies balsamea). P i o n e e r s p e c i e s s u c h as
s i l v e r - w e e d (PotentilZa anserinaj c l o s e l y a s s o c i a t e d w i t h t h e l a n d - w a t e r i n t e r f a c e were o b s e r v e d a t 6.7 m i l e s n o r t h w e s t o f H u r o n Beach, M i c h i g a n , on U.S. Route 23.' O t h e r s a m p l i n g p o i n t s a l o n g Lake Huron were a t 5.9 and 2.8 m i l e s n o r t h w e s t o f Huron Beach, M i c h i g a n , on U.S. Route 23. P l a n t s o b s e r v e d a t t h e f o r m e r s i t e i n c l u d e d wheat g r a s s (Agropyron
dasystaahyim), w i l d r y e , f a l s e Solomon's s e a l , sand c h e r r y , b e a c h - p e a ,
and r e d o s i e r dogwood; t h e l a t t e r s i t e c o n t a i n e d w i l d r y e , h e a r t - l e a v e d w i l l o w , sand c h e r r y , and b e a r b e r r y .
4. Lake E r i e .
Severe bank e r o s i o n was e v i d e n t a l o n g a l l o f t h e Lake E r i e s h o r e examined. The f r e q u e n t wave a t t a c k on t h e s h o r e p r e v e n t s e s t a b l i s h -ment o f submergent and emergent h y d r o p h y t e s t h a t m i g h t be u s e d f o r
e r o s i o n c o n t r o l .
T e r r e s t r i a l p l a n t s o b s e r v e d a l o n g t h e Lake E r i e s h o r e were c o t t o n -wood (Populus deltoides) s a n d b a r w i l l o w n e a r S t e r l i n g S t a t e P a r k , M i c h i g a n , a n d c o t t o n w o o d and w i l d r y e a t Presque I s l e S t a t e P a r k n e a r E r i e , P e n n s y l v a n i a . None o f t h e s e p l a n t s was e.xposed t o waves.
A b r e a k w a t e r j e t t y a t A s h t a b u l a , Ohio, p r o d u c e d a s t i l l i n g e f f e c t b e t w e e n t h e s t r u c t u r e and t h e s h o r e , p r o v i d i n g h a b i t a t f o r r e e d
( F i g . 9 ) .
5. Lake O n t a r i o .
Wave a c t i o n and e r o s i o n a l o n g Lake O n t a r i o s h o r e s were as s e v e r e as a l o n g Lake E r i e s h o r e s ; no e r o s i o n - c o n t r o l l i n g h y d r o p h y t i c o r t e r r e s t r i a l p l a n t s were o b s e r v e d .
A t H a m l i n Beach S t a t e P a r k , New Y o r k , a h i g h sandbank was g r a d e d t o a s l o p e o£ 1:12 ( 1 u n i t v e r t i c a l t o 12 u n i t s h o r i z o n t a l ) and s e e d e d w i t h a g r a s s m i x t u r e t o s t a b i l i z e t h e sand a g a i n s t e r o s i o n ( F i g . 1 0 ) . B e f o r e r e s h a p i n g , t h e sandbank v^^as b e i n g eroded by waves; t h e s h o r e has now s t a b i l i z e d and i s a h e a v i l y used r e c r e a t i o n a l a r e a .
I V . RESULTS AND DISCUSSION 1. L i t e r a t u r e Review .
The most p r o m i s i n g i n f o r m a t i o n f r o m t h e l i t e r a t u r e on use o f v e g e -t a -t i o n f o r e r o s i o n c o n -t r o l was f r o m E d m i n s -t e r ( 1 9 4 9 ) , who s u g g e s -t s p l a n t e s t a b l i s h m e n t t o c o n t r o l e r o s i o n o f s t r e a m b a n k s . M u l c h t e c h n i q u e s t o t e m p o r a r i l y c o n t r o l e r o s i o n and t o h e l p e s t a b l i s h v e g e t a t i o n , w i t h d e f i n i t e g u i d e l i n e s f o r e s t a b l i s h i n g and m a i n t a i n i n g v e g e t a t i o n , a r e p u b l i s h e d b y t h e S o i l C o n s e r v a t i o n S e r v i c e (1966, 1 9 6 9 ) . A s t u d y o f t h e e r o s i o n p r o b l e m o f B e r r i e n County, M i c h i g a n , i d e n t i -f i e d p r o b l e m l o c a l i t i e s and -f a c t o r s c o n t r i b u t i n g t o t h e p r o b l e m s and s u g g e s t e d c o r r e c t i v e a c t i o n (U.S. Congress, 1 9 5 8 ) . A more r e c e n t s t u d y f o r Lakes M i c h i g a n and Huron was made b y t h e M i c h i g a n W a t e r R e s o u r c e s Commission ( B r a t e r and S e i b e l , 1973). T h a t e n g i n e e r i n g s t u d y d e t e r m i n e d t h e s e v e r i t y o f e r o s i o n and t h e r a t e o f b l u f f r e c e s s i o n a t s e l e c t e d l o c a t i o n s . The Ohio Department o f N a t u r a l Resources (1961) p e r f o r m e d a s i m i l a r s t u d y f o r t h e Ohio s h o r e l i n e a l o n g Lake E r i e ; t h e U.S. Army E n g i n e e r D i v i s i o n , N o r t h C e n t r a l ( 1 9 7 1 ) , c o n d u c t e d a g e n e r a l s t u d y o f e r o s i o n on a l l t h e G r e a t Lakes. The U.S. Army, Corps o f E n g i n e e r s
(1971a) e s t a b l i s h e d s h o r e management g u i d e l i n e s and a l s o p u b l i s h e d g u i d e l i n e s f o r s h o r e p r o t e c t i o n ( 1 9 7 1 b ) .
C a r t e r (1973) d e s c r i b e d and e v a l u a t e d s t r u c t u r e s and n a t u r a l f e a -t u r e s r e l a -t i v e -t o e r o s i o n o f -t h e Lake E r i e s h o r e l i n e . The S -t a -t e o f M i n n e s o t a p u b l i s h e d two r e p o r t s on s h o r e management ( M i n n e s o t a D e p a r t ment o f N a t u r a l R e s o u r c e s , 1971a, b ) . A r e p o r t on low c o s t s h o r e p r o -t e c -t i o n f o r -t h e G r e a -t Lakes was p u b l i s h e d b y -t h e U n i v e r s i -t y o f M i c h i g a n
( 1 9 5 9 ) , and, a l t h o u g h c o s t s have i n c r e a s e d , c o n s t r u c t i o n methods r e m a i n t h e same.
L i t e r a t u r e s o u r c e s (Lamson and S c r i b n e r , 1894; Cowles, 1899; Weaver and Clements, 1938; S o i l C o n s e r v a t i o n S e r v i c e , 1974) p r o v i d e l i s t s o f p l a n t s p e c i e s p o t e n t i a l l y u s e f u l f o r e r o s i o n c o n t r o l . The e r o s i o n abatement p o t e n t i a l o f t h e s e i s u s u a l l y f u r t h e r enhanced i f s e v e r a l s p e c i e s a r e m i x e d w i t h i n an a r e a ; many o f t h e p l a n t s o c c u r n a t u r a l l y i n a s s o c i a t i o n w i t h one o r two o t h e r s p e c i e s . C o l o n i z i n g c a t e g o r y , m o r p h o l o g i c a l a d a p t a t i o n s , s e a s o n a l o c c u r r e n c e , and g r o w t h f o r m o f p l a n t s p e c i e s d e r i v e d f r o m l i t e r a t u r e s o u r c e s a r e l i s t e d i n T a b l e 3. 2. F i e l d S u r v e y .
a. Emergent and Submergent V e g e t a t i o n . The c o a s t l i n e o f t h e G r e a t
24
T a b l e 3. C h n r n c t o r l s t l c s o f p l a n t s i d e n t i f i e d d u r i n g l i t e r a t u r e r e v i e w t h a t a r e e f f e c t i v e f o r e r o s i o n abatement a l o n g t h e Great Lakes s h o r e l i n e . Coimnon Name S c i e n t i f i c Name C h a r a c t e r i s t i c s
ttheac g r a s s Agropyron dagyetachyum P i o n e e r , rhi;omatous, herbaceous p e r e n n i a l o c c u r r i n g orr dunes and droughty s o i l ; t r a p s sand, forms dunes
Quack g r a s s Agropyron reparw P i o n e e r , rhi:omatous, herbaceous p e r e n n i a l o c c u r r i n g a l o n g g r a v e l l y c o a s t s ; b i n d s s l o p e s
European b e a c h g r a s s Aimophila armaria P i o n e e r , r h l i o m a t o u s , herbaceous p e r e n n i a l o c c u r r i n g a l o n g t h e c o a s t ; t r a p s sand, forma dunes
American b e a c h g r a s s Aimophila brnviliffuUitil P i o n e e r , rhizomatous, herbaceous p e r e n n i a l o c c u r r i n g on dunes L i t t l e b l u c s t c n Andropogon ecopariua P i o n e e r , rhizomatous, herbaceous p e r e n n i a l o c c u r r i n g i n open f i e l d s and
B e a r b e r r y AratoatiXphytoe uva-urai Secondary, p e r e n n i a l woody shrub o c c u r r i n g on sand and exposed r o c k ; f o r a s
Smooth brcntc g r a s s BromuB ir^arvla P i o n e e r , r h i i o m a t o u s - s t o l o n i f e r o u s , herbaceous p e r e n n i a l o c c u r r i n g a l o n g r o a d s i d e s and f i e l d s ; forms t u r f , s t a b i l i z e s S l o p e s
P r a i r i e sandreed Catatrtovitfa lanffifalia P i o n e e r , r h i z o m a t o u s , herbaceous p e r e n n i a l o c c u r r i n g on sand, o f t e n w i t h European b e a c h g r a s s ; t r a p s sand
Buttonbush CcphaUinthua ocddantalig Secondary, p e r e n n i o l woody shrub o c c u r r i n g i n swamps ond s t r e a n b a n k s ; s l o w l y a c c u m u l a t e s sand and c r e a t e s dunes
I n l a n d s e a o a t s OuxoTtanChium latifoHim P i o n e e r , rhizomatous, herbaceous p e r e n n i a l o c c u r r i n g i n «wist woods and low t h i c k e t s ; b i n d s s t r e a m s and r i v e r banks
I n d i a n reed g r a s s Cinna arundinacaa P i o n e e r , rhizomatous, herbaceous p e r e n n i a l o c c u r r i n g i n n o i s t woods and shaded swamps; b i n d s streams and r i v e r banks
Red o s i e r dogwood Comue otolonifarv Secondary, s t o l o n l f c r o u s , p e r e n n i a l woody shrub o c c u r r i n g i n t h i c k e t s and on s h o r e s ; 'forms dunes
PersiesBon Dioapt/roa virginiana T e r t i a r y , p e r e n n i a l t r e e o c c u r r i n g on abandoned f i e l d s ; e f f e c t i v e f o r dune s t a b i l i z a t i o n
Autumn o l i v e Elacagnua wrhatlata Secondary, p e r e n n i a l woody shrub o c c u r r i n g i n t h i c k e t s and on r o a d s i d e banks; e f f e c t i v e f o r dune s t a b i l i z a t i o n
Sea IjTiie g r a s s , c i r c a 189^ (Wild r y e )
Elymua arcnariua (E. mollU}
P i o n e e r , rhizomatous, herbaceous p e r e n n i a l o c c u r r i n g on sandy b e a c h e s ; .often grows w i t h European b e a c h g r a s s
tfi I d r y e Elynjuo canadcnaie P i o n e e r , r h i z o m a t o u s , herbaceous p e r e n n i a l o c c u r r i n g on sandy, g r a v e l l y , rocky s o i l ; s t a b i l i z e s sandy s u r f a c e s
B l a c k h u c k l e b e r r y Gayluooana baccata Secondary, p e r e n n i a l woody shrub o c c u r r i n g i n woods, t h i c k e t s , and c l e a r i n g s ; o f t e n o c c u r s w i t h j u n i p e r s t o form dunes
Rush Jtmcuo baZticuo P i o n e e r , r h i z o m a t o u s , herbaceous p e r e n n i a l o c c u r r i n g on sandy, b r a c k i s h t o f r e s h w a t e r s h o r e s ; forms s m a l l dunes
J u n i p e r Junipama ccvnunio Secondary, p e r e n n i a l woody shrub o c c u r r i n g on droughty s o i l s ; fonas dunes Knot-root g r a s s Muhlenhcrgia mexicana P i o n e e r , rhizomatous, herbaceous p e r e n n i a l o c c u r r i n g a l o n g s h o r e s ,
t h i c k e t s , damp c l e a r i n g s , and sandy s o i l s
No comaon name Paronychia ;aneaa-C Secondary, p e r e n n i a l woody shrub o c c u r r i n g on r o c k s l o p e s , b r e a k s , dunes, and c l a y s o i l s ; adapted t o g r a v e l l y s o i l s
Reed c a n a r y g r a s s Phalaria csr^ndinaaaa Pioneer, r h i z o m a t o u s , herbaceous p e r e n n i a l o c c u r r i n g a l o n g s h o r e s , s w a l e s , and meadows; c o n t r o l s stream bank e r o s i o n
CoaB>on reed g r a s s Fhragnrltce auatrali-a P i o n e e r , r h i z o m a t o u s . herbaceous p e r e n n i a l ; s i m i l a r t o Tocd c a n a r y g r a s s J a p a n e s e b l a c k p i n e Pinua thuKgcrgii T e r t i a r y , p e r e n n i a l t r e e ; h o r t i c u l t u r a l ; e f f e c t i v e f o r dune s t a b i l i z a t i o n K a t e r snaVtweed Polygonum cnrphibium Secondary, r h i z o m a t o u s . herbaceous p e r e n n i a l o c c u r r i n g i n meadows, swaaps,
s h o r e s , and d i t c h e s ; t r a p s sand and forms dunes
Balsam p o p l a r Fopulue bcLlaoïïifara T e r t i a r y , p e r e n n i a l t r e e o c c u r r i n g a l o n g r i v e r b a n k s ; forms dunes S i l v e r - w e e d Potanti-lla anaeri-na P i o n e e r , s t o l o n l f c r o u s . herbaceous p e r e n n i a l o c c u r r i n g on sandy s h o r e s
and banks; t r a p s sand, forms dunes
Beach plum Prunus maritxma. Secondary, p e r e n n i a l woody shrub o c c u r r i n g on c o a s t a l sandy s o i l s ; e f f e c t i v e f o r sand dune s t a b i l i z a t i o n
Sand c h e r r y Prunua purriZa Secondary, p e r e n n i a l woody shrub o c c u r r i n g on dunes, sand, and c a l c a r e o u s , rocky s h o r e s ; dune b u i l d e r
'Amot' b r i s t l y locus^ nohinia f f t r t i l i a (E. kiopida}
T e r t i a r y , p e r e n n i a l t r e e o c c u r r i n g i n d r y woods, t h i c k e t s , and on s l o p e s j e f f e c t i v e f o r sand dune s t a b i l i z a t i o n
H e a r t - l e a v e d w i l l o w Salix aordata Secondary, p e r e n n i a l woody shrub o c c u r r i n g on g r a v e l l y , sandy s h o r e s , t e a c h e s , and dunes; dune b u i l d e r
Dune w i l l o w Salix glaucophylloidee Secondary, p e r e n n i a l woody shrub o c c u r r i n g on g r a v e l l y s h o r e s , t h i c k e t s , and m a i n l y on c a l c a r e o u s s o i l s ; dune b u i l d e r
C o r d g r a s s Spartina pactinata P i o n e e r , r h i z o m a t o u s , herbaceous p e r e n n i a l o c c u r r i n g a l o n g s h o r e s , i n swamps and wet p r a i r i e s ; sand s t a b i l i z e r
F o r e s t - g r a p e Vitio viiZpina Secondary, p e r e n n i a l woody shrub o c c u r r i n g a l o n g r i v e r bonks, i n b o t t o a -l a n d s ond t h i c k e t s ; c h e c k s advance o f sand on p r o t e c t e d sand dune s -l o p e s
Lakes i s m o s t l y a b r u p t , a l t h o u g h , t h e r e a r e some p r o t e c t e d areas on t h e n o r t h e r n s h o r e o f Lake Huron and a l s o a t C e c i l Bay w e s t o f Mackinaw C i t y , M i c h i g a n . These p r o t e c t e d a r e a s have s h o r e s c o n d u c i v e t o a q u a t i c p l a n t g r o w t h b u t t h e g e n t l e a c t i o n o f t h e w a t e r t h e r e has r e s u l t e d i n no e r o s i o n h a z a r d . Thus, a r e a s where a q u a t i c p l a n t s w i l l s u r v i v e a r e n o t a r e a s o f p r i m a r y c o n c e r n r e l a t i v e t o e r o s i o n . Where e r o s i o n and s h o r e l i n e r e c e s s i o n i s a m a j o r p r o b l e m , t h e c o a s t l i n e c o n d i t i o n s and wave a c t i o n p r e v e n t g r o w t h o f h y d r o p h y t e s , e s p e c i a l l y submergent p l a n t s .
Wave a c t i o n a l o n g t h e s h o r e s o f Lakes S u p e r i o r , E r i e , and O n t a r i o p r e v e n t s e s t a b l i s h m e n t o f any h y d r o p h > t i c p l a n t s t h a t m i g h t have e r o s i o n - c o n t r o l l i n g p r o p e r t i e s .
Lakes M i c h i g a n and Huron have some p r o t e c t e d bays and i n l e t s s u i t -a b l e f o r emergent -and submergent v e g e t -a t i o n . P l -a n t s o b s e r v e d t h e r e were h e r b a c e o u s t e r e t e s p e c i e s . O t h e r p l a n t s , such as g r e a t b u l r u s h , s p i k e r u s h , and b u l r u s h , w i l l e s t a b l i s h t h e r e i f t h e s h o r e i s g e n t l y s l o p i n g .
A g e n t l y s l o p i n g s h o r e on Lake Huron 3.5 m i l e s e a s t o f t h e S t a t e Route 134 and I n t e r s t a t e 75 i n t e r c h a n g e p r o v i d e d h a b i t a t f o r b l u e j o i n t , g r e a t b u l r u s h , and r u s h . These p l a n t s w i l l n o t w i t h s t a n d h a r s h wave a c t i o n ; t h e y c a n n o t be c o n s i d e r e d s u i t a b l e ' f o r wave a t t e n u a t i o n .
One o f t h e f e w e x c e l l e n t h a b i t a t s f o r emergent h y d r o p h y t e s was f o u n d on Lake M i c h i g a n a t C e c i l Bay, where g r e a t b u l r u s h and s p i k e r u s h were v e r y e f f e c t i v e i n wave dampening.
b. T e r r e s t r i a l V e g e t a t i o n and Shore A l t e r a t i o n s . The a b i l i t y o f a s h o r e l i n e t o r e s i s t e r o s i o n , o r i t s r e s i l i e n c y t o w a t e r dynamics, de-pends upon t h e c o m p o s i t i o n o f m a t e r i a l m a k i n g up t h e s h o r e f r o n t and t h e a d a p t a b i l i t y o f i t s v e g e t a t i o n . The e r o s i o n r e s i s t a n c e o f t h e G r e a t Lakes s h o r e s d i m i n i s h e s f r o m t h e r o c k b l u f f s and r o c k y s h o r e l i n e s o f Lakes S u p e r i o r and H u r o n , t o t h e sandy beaches o f Lake M i c h i g a n , t o t h e s i l t y - c l a y b l u f f s a l o n g Lake E r i e . S i m i l a r l y , t h e e r o s i o n abatement p o t e n t i a l o f t h e t e r r e s t r i a l v e g e t a t i o n v a r i e s f r o m l o c a t i o n t o l o c a -t i o n a l o n g -t h e G r e a -t Lakes s h o r e s .
Q u a l i t a t i v e e v a l u a t i o n s o f t h e e r o s i o n - c o n t r o l l i n g p o t e n t i a l o f each v e g e t a t i v e s p e c i e s were o b t a i n e d -in situ u s i n g t h e s c o r e c a r d ( T a b l e 1 ) . S p e c i e s f o u n d d u r i n g t h e f i e l d s u r v e y a r e l i s t e d i n T a b l e 4, and a n a v e r a g e s i t e i n d e x o f t h e o b s e r v e d s p e c i e s i s g i v e n i n T a b l e 5. V e g e t a t i v e s p e c i e s c l a s s i f i e d as e x c e l l e n t f o r e r o s i o n abatement i n t h e i r e c o l o g i c a l l y a d a p t e d a r e a s i n c l u d e d balsam f i r m , j u n i p e r , c r e e p i n g c e d a r , brome g r a s s , r e e d (Pkragmites eommunis), w i l d r y e , b l u e -j o i n t , p r a i r i e s a n d r e e d , s p i k e r u s h , g r e a t b u l r u s h , r u s h , b a l s a m p o p l a r , c o t t o n w o o d , s p e c k l e d a l d e r (Alnus rugosa), s i l v e r - w e e d , beach-pea, f a l s e h e a t h e r , r e d o s i e r dogwood, and b e a r b e r r y . The r e m a i n i n g s p e c i e s c l a s s i f i e d as good i n c l u d e s c o u r i n g r u s h , wheat g r a s s , w i l d r y e , r e e d c a n a r y g r a s s (Phalaris arundinaaea), b u l r u s h (Sairpus
p e p p e r - g r a s s , w i l d r o s e , sand c h e r r y , f o r e s t - g r a p e , and t a n s y . Most p l a n t s were o b s e r v e d i n h e t e r o g e n e o u s s t a n d s w i t h no p r o n o u n c e d dominance by an i n d i v i d u a l s p e c i e s .
S p e c i e s most e f f e c t i v e as sand a c c u m u l a t o r s have a l o w - g r o w t h p r o f i l e w i t h m i n o r v e r t i c a l s t r a t i f i c a t i o n . S p e c i e s e x e m p l i f y i n g t h i s
g r o w t h h a b i t i n c l u d e most g r a s s e s , j u n i p e r , c r e e p i n g c e d a r , r u s h , f a l s e Solomon's s e a l , s i l v e r - w e e d , beach-pea, b e a r b e r r y , and t a n s y .
P l a n t s common t o b o t h l i t e r a t u r e and v e g e t a t i v e s u r v e y s were: w i l d r y e , p r a i r i e s a n d r e e d , r e e d c a n a r y g r a s s , w h e a t g r a s s , h e a r t -l e a v e d w i -l -l o w , sand c h e r r y , r e d o s i e r dogwood, ba-lsam p o p -l a r , r u s h , b e a r b e r r y , j u n i p e r (Jun-iperus communis), and s i l v e r - w e e d .
Land a l t e r a t i o n has p r o v e d e s s e n t i a l f o r c o n t r o l l i n g s h o r e and bank e r o s i o n i n many a r e a s o f t h e G r e a t L a k e s . Near Kewaunee, W i s c o n s i n , f o r example, seepage c o n t r i b u t e s t o bank f a i l u r e a l o n g Lake M i c h i g a n . The S o i l C o n s e r v a t i o n S e r v i c e has s u c c e s s f u l l y i n s t a l l e d a deep t i l e l i n e t o i n t e r c e p t seepage and c o n d u c t t h e u n d e r g r o u n d w a t e r t o Lake M i c h i g a n . The banks were r e s h a p e d t o an a p p r o x i m a t e s l o p e o f 2:1 and t h e s o i l was seeded w i t h a m i x t u r e o f crown v e t c h and f e s c u e t o c o n t r o l s u r f a c e r u n -o f f . S i m i l a r d e w a t e r i n g has been e f f e c t i v e i n u r b a n and r u r a l a r e a s . The w o r k i s c o s t l y , e s p e c i a l l y on h i g h b a n k s . I n t i m e , i f s e e d i n g has s u c c e s s f u l l y s t a b i l i z e d s o i l on t h e b a n k s , n a t i v e p l a n t s p e c i e s i n v a d e and become e s t a b l i s h e d a l o n g w i t h p l a n t e d s p e c i e s .
C l a y w i t h g l a c i a l o v e r b u r d e n c o n t a i n i n g sand and g r a v e l l e n s e s can be e f f e c t i v e l y d e w a t e r e d p r o v i d e d t h e r e i s a d i s c h a r g e o u t l e t t o d i s -pose o f t h e i n t e r c e p t e d s u r f a c e and seepage w a t e r . Because o f h i g h c o s t , d e w a t e r i n g must be c a r e f u l l y e v a l u a t e d .
The c r i t i c a l f a c t o r f o r s u c c e s s i n t h i s t y p e o f s t a b i l i z a t i o n i s e f f e c t i v e d e w a t e r i n g o f t h e s o i l and e s t a b l i s h i n g o f v e g e t a t i v e c o v e r t o p r e v e n t s u r f a c e e r o s i o n .
An example o f a Lake M i c h i g a n s h o r e m o d i f i c a t i o n i s shown i n
F i g u r e 1 1 . The s i t e was i n R a c i n e C o u n t y a b o u t 3 m i l e s n o r t h o f R a c i n e , W i s c o n s i n . Rock was u s e d f o r s h o r e l i n e p r o t e c t i o n t o m i n i m i z e e r o s i o n o f t h e embankment. The r o u g h s t e e p b a n k was g r a d e d t o a more g e n t l e s l o p e and was seeded t o c o n t r o l s u r f a c e e r o s i o n . T h i s s h o r e f r o n t mod-i f mod-i c a t mod-i o n r e q u mod-i r e s a s o mod-i l t h a t mod-i s n o t s u b j e c t t o seepage so s e v e r e t h a t i t causes bank f a i l u r e . Loam s o i l i s b e s t f o r t h i s t y p e o f r e c l a m a t i o n . The b e s t v e g e t a t i v e g r o w t h i s o b t a i n e d b y t o p d r e s s i n g w i t h f e r t i l i z e r and i r r i g a t i n g . Where a s p e c i f i c t y p e o f v e g e t a t i o n i s d e s i r e d , weed c o n t r o l may a l s o be r e q u i r e d . T h i s s h o r e f r o n t r e n o v a t i o n r e q u i r e s c o n s t a n t management t o m a i n t a i n a t u r f a p p e a r a n c e .
R e f o r m i n g and v e g e t a t i n g t h e b e a c h a t H a m l i n S t a t e P a r k , New York, on Lake O n t a r i o ( F i g . 10) was s u c c e s s f u l . A h i g h sandbank was r e -shaped t o a 1:12 s l o p e t o r e d u c e e r o s i o n by d i s s i p a t i n g wave e n e r g y . The beach and i t s a d j a c e n t r e c r e a t i o n a l a r e a were v e g e t a t e d t o c o n t r o l s u r f a c e e r o s i o n . S i n c e t h i s s h o r e l i n e m o d i f i c a t i o n was f o r r e c r e a t i o n .
g u r e 1 1 . R e f o r m a t i o n o f r o u g h bank (above) and l a n d s c a p i n g o f s h o r e l i n e ( b e l o w ) .
a s p e c i e s a b l e t o w i t h s t a n d f r e q u e n t mowing was u s e d . T h i s t y p e o f v e g e t a t i o n r e q u i r e s c o n s t a n t management. U n f o r t u n a t e l y , n o t a l l s o i l s a r e a d a p t e d f o r t h i s t y p e o f e r o s i o n c o n t r o l . Coarse sands a r e w e l l a d a p t e d , w h i l e s i l t and c l a y s o i l s a r e n o t ; t h e i r v e r y f i n e p a r t i c l e s a r e e a s i l y moved b y w a t e r . c. V e g e t a t i o n i n C o m b i n a t i o n w i t h S t r u c t u r e s . D u r i n g t h e f i e l d s u r v e y , t h r e e s t r u c t u r e s were o b s e r v e d t h a t were s u c c e s s f u l , i n com-b i n a t i o n w i t h v e g e t a t i o n , i n c o n t r o l l i n g s h o r e l i n e e r o s i o n . The
st3ructures w e r e l o c a t e d on Lakes S u p e r i o r , M i c h i g a n , and E r i e , a n d were o f t h r e e d i f f e r e n t t y p e s : r i p r a p , s e a w a l l w i t h g r o i n , a n d j e t t y .
Near t h e s t a t e h i g h w a y a t H e r b s t e r , W i s c o n s i n , on Lake S u p e r i o r , r i p r a p was i n s t a l l e d t o a b a t e bank e r o s i o n . The r i p r a p has s t a b i l i z e d t h e bank a g a i n s t wave a c t i o n ; a w e l l - e s t a b l i s h e d v e g e t a t i v e c o v e r has d e c r e a s e d t h e r u n o f f r a t e .
A n o t h e r s t r u c t u r e t h a t i s s u c c e s s f u l i n c o n t r o l l i n g bank e r o s i o n i s a c o n c r e t e s e a w a l l and g r o i n a t t h e K e n i l w o r t h , I l l i n o i s , P u b l i c Water Works o n Lake M i c h i g a n ( F i g . 7 ) . Lake l e v e l i n c r e a s e s h e r e have g r e a t l y r e d u c e d a p r i v a t e beach t h a t f r o n t e d t h e s e a w a l l , b u t t h e w a l l i s v e r y e f f e c t i v e i n d i s s i p a t i n g wave e n e r g y . The dense and w e l l -e s t a b l i s h -e d v -e g -e t a t i o n b -e h i n d t h -e w a l l s u c c -e s s f u l l y p r -e v -e n t s s u r f a c -e r u n o f f e r o s i o n o n t h e bank.
On Lake E r i e , a t A s h t a b u l a , O h i o , a j e t t y ( F i g . 9) has e f f e c t i v e l y dampened wave a c t i o n so t h a t a p o o l has f o r m e d between t h e s h o r e and t h e s t r u c t u r e i t s e l f . The q u i e t e r p o o l a r e a i s a d e s i r a b l e h a b i t a t f o r r e e d , w h i c h i n t u r n p r o v i d e s a q u a t i c h a b i t a t and enhances t h e a e s t h e t i c q u a l i t y o f t h e s h o r e .
V. SUMMARY AND CONCLUSIONS
A t t e m p t s t o e s t a b l i s h v e g e t a t i o n on t h e s h o r e s o f t h e G r e a t Lakes, p a r t i c u l a r l y Lakes E r i e and O n t a r i o , f o r e r o s i o n abatement a r e n o t ex-p e c t e d t o be s u c c e s s f u l w i t h o u t s t r u c t u r a l wave damex-pening, a n d o f t e n ,
l a n d r e f o r m i n g . A f t e r wave f o r c e h a s been r e d u c e d and t h e s h o r e l i n e s t a b i l i z e d b y u s e o f s t r u c t u r a l methods, v e g e t a t i o n c a n be e s t a b l i s h e d t o f u r t h e r s t a b i l i z e t h e s o i l , and t h u s r e d u c e s u r f a c e e r o s i o n r e s u l t i n g f r o m r u n o f f . I f v e g e t a t i o n i s t o b e e s t a b l i s h e d t o dampen waves and t o l i m i t i n l a n d wave p e n e t r a t i o n , some r e f o r m i n g t o d e v e l o p a g r a d u a l s l o p e o f t h e f o r e s h o r e i s d e s i r a b l e and may be f e a s i b l e i n p l a c e s .
E s t a b l i s h m e n t a n d m a i n t e n a n c e o f a n e f f e c t i v e v e g e t a t i v e c o v e r on sandy a r e a s w i l l r e q u i r e f e r t i l i z i n g and i r r i g a t i n g , and c o n t i n u o u s m a i n t e n a n c e w i l l be n e c e s s a r y . The v e g e t a t i o n s e l e c t e d must be com-p a t i b l e w i t h t h e l a n d use, com-p a r t i c u l a r l y i f t h e a r e a has com-p u b l i c a c c e s s . B e f o r e a n y a t t e m p t i s made t o s t a b i l i z e t h e sand w i t h v e g e t a t i o n , t h e e f f e c t o f seepage must be e v a l u a t e d t o d e t e r m i n e i f d e w a t e r i n g i s needed f o r a f i r m s a n d - c l a y i n t e r f a c e .
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The p r i n c i p a l use o f v e g e t a t i o n o n t h e G r e a t Lakes s h o r e s i s t o a b a t e s u r f a c e e r o s i o n caused b y r u n o f f o r w i n d . P l a n t s f o u n d f r e q u e n t l y d u r i n g t h e s u r v e y a r e f a l s e Solomon's s e a l , w i l d r y e , and sand c h e r r y . I n f o r m a t i o n on s u r f a c e e r o s i o n and t h e v a r i o u s t e c h n i q u e s f o r i t s con-t r o l ( d e w a con-t e r i n g , s l o p e g r a d i n g , sand s con-t a b i l i z a con-t i o n ) a r e a v a i l a b l e f r o m t h e S o i l C o n s e r v a t i o n S e r v i c e o r t h e C o u n t y A g r i c u l t u r e E x t e n s i o n A g e n t .
F u r t h e r r e s e a r c h on u s e o f a q u a t i c p l a n t s f o r e r o s i o n abatement on t h e G r e a t Lakes s h o r e s i s n o t recommended because open s h o r e l i n e c o n d i t i o n s a r e n o t f a v o r a b l e f o r t h e g r o w t h _ a n d m a i n t e n a n c e o f i n t r o d u c e d submergent and emergent p l a n t s .
