Eastern Illinois University The Keep

Masters Theses Student Theses & Publications

1993 A Preliminary Study Using the Cutting Method to Reduce Lake Shoreline Erosion Jeffrey L. Bushur This research is a product of the graduate program in Botany at Eastern Illinois University. Find out more about the program.

Recommended Citation Bushur, Jeffrey L., "A Preliminary Study Using the Willow Cutting Method to Reduce Lake Shoreline Erosion" (1993). Masters Theses. 2071. https://thekeep.eiu.edu/theses/2071

This is brought to you for free and open access by the Student Theses & Publications at The Keep. It has been accepted for inclusion in Masters Theses by an authorized administrator of The Keep. For more information, please contact [email protected]. THESIS CERTIFICATE

TO: Graduate Degree Candidates who have written formal theses.

SUBJECT: Permission to reproduce theses.

The University Library is receiving a number of requests from other institutions asking permission to reproduce dissertations for inclusion in their library holdings. Although no copyright laws are involved, we feel that professional courtesy demands that permission be obtained from the ·author before we allow theses to be copied.

Please sign one of the following statements:

Booth Library of Eastern Illinois University has my permission to lend my thesis to a reputable college or university for the purpose of copying it for inclusion in that institution's library or research holdings.

8·-tf-? 3

Date Author

I respectfully request Booth Library of Eastern Illinois University not allow my thesis be reproduced because ~~~--~------~----~---

Date Author

m A PRELIMINARY STUDY USING WILLOW CUTTINGS

TO REDUCE LAKE SHORELINE EROSION (TITLE)

BY JEFFREY L. BUSHUR

v B.S., EASTERN ILLINOIS UNIVERSITY, 1991

THESIS

SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF

MASTER OF SCIENCE

IN THE GRADUATE SCHOOL, EASTERN ILLINOIS UNIVERSITY CHARLESTON, ILLINOIS

1993 YEAR

I HEREBY RECOMMEND THIS THESIS BE ACCEPTED AS FULFILLING THIS PART OF THE GRADUA{E DEGREE CITED ABOVE 75/5/73 - . g/3/?3 DATE

DATE ABSTRACT

13ushur, Jeffrey L. M.S., Eastern Illinois University. August 1993. A preliminary study using the wilJow cutting method to reduce lake shoreline erosion.

The Charleston Side-Channel Reservoir has been experiencing extensive shoreline erosion since its completion in 1982. A diagnostic/feasibility study of the reservoir in 1992 rated shoreline erosion as the second largest source of sedimentation. Sedimentation reduces the reservoir volume, increases nutrient loading, and increases water turbidity.

As a part of Clean Lakes Program Phase If, the use of willow cuttings for bank stabilization was proposed as a possible treatment for shoreline erosion. While the use of for streambank stabilization has been extensively reported, lake documentation is rare. This experiment determined the feasibility of such action for the Charleston Side-Channel Reservoir and the extent of bank stabilization success.

Four sites around the reservoir were designated as test areas. Each site consisted of 24 m (80 ft) of shoreline and contained an untreated control section (c), and erosion-control matting section (m), a section of willow treatment alone (w), and a section of willow and matting treatment in combination (mw). Planting material was taken from a nearby stand of sandbar willows (Salix interior), cut into 0.9 m (3 ft) lengths, and planted in four, staggered rows along the banks. I~einforcement bars were driven into the banks before treatment in order to monitor erosional rates.

Propagation success was very high after the cuttings broke dormancy in

Spring of 1992. Out of 477 cuttings planted, 442 (92.7%) had produced ii

. By October 1992, 380 (79.7%) still remained viable. The number surviving plummeted to 141 (29.6%) in May 1993. After reservoir levels rose as a result of excessive precipitation in the spring, all sites except site 3 showed a drastic reduction in willow survival. Wave erosion caused the collapse of large amounts of sediment from the cliff face, thereby uprooting or burying cuttings. The erosion-control fabric was found to increase survival by about 20% on sites having mw survival ratios significantly greater than w ratios. Both site 3 (p=0.0317) and site 4 (p=0.0025) had mw values significantly larger than w values. The use of matting is not advised in future willow cutting projects, however, considering labor, material cost, and survival benefits. This project has demonstrated some success in willow establishment but may fail in long-term bank protection under all conditions. Future planting on low erosion areas is more feasible than on high erosion areas. Combinations of shoreline stabilization techniques in order to reduce wave action will most likely be required. iii

ACKNOWLEDGEMENTS

I wish to express my sincere gratitude to Dr. William Weiler for his contributions to this research, his advisement in the preparation of the writing, and for his academic guidance and friendship throughout my time at Eastern Illinois University. I am very grateful to Dr. Vincent Gutowski for the time and effort which he freely gave and for his helpful suggestions in matters concerning shoreline erosion. I wish to thank Mr. Alan Alford and members of the Charleston Water Treatment Plant not only for help and support on the project but also for the rewarding time I had as a graduate assistant at the plant. I am grateful to Dr. Kipp Kruse for his adice on the statistical aspects of the paper. I wish to thank Mr. Hank Nilsen, Dr. Charles Pederson, and Dr. Clay Pierce for their helpful suggestions in the completion of this paper. I wish to express a special thanks to my cousin, Mr. Wayne Bushur, for his computing expertise and assistance without which this writing would have been considerably more difficult. I wish to thank all of the crew members of the Departments of Geology/Geography (Plate 1), Botany, and Zoology who volunteered their time during February of 1992. And finally, a hardy thanks goes to my family for much-needed moral support and financial assistance. iv

TABLE OF CONTENTS

ABSTRACT i

ACKNOWLEDGEMENTS iii

TABLE OF CONTENTS iv

LIST OF TABLES v

LIST OF FIGURES vi

LIST OF PLATES vii

LITERATURE REVIEW 1

METHODS AND MATERIALS 19

RESULTS AND DISCUSSION 29

CONCLUSIONS AND RECOMMEND A TI ONS 61

LITERATURE CITED 65

APPENDIX A 68 v

LIST OF TABLES

Table Page

1 Erosional Classification of the Perimeter of the 9 Charleston Side-Channel Reservoir

2 Vascular Plants of the Charleston Side-Channel 12 Reservoir

3 Dates of Rebar, Matting, and Willow Placement 21 for Sites 1-4

4 Physical Characteristics of Sites 1-4 30

5 Uprooted Deaths Versus Intact Deaths by Section - 49 May and October 1992

6 Water Levels of Willow Rows and Percentage of 54 Time at or below Water Level

7 Mean Exposed ( +) or Buried (-) Centimeters of Rebar 56 - May 1993

8 Differences in Mean Control Rebar Measurements in 57 Centimeters (Inches) Between Time Periods May 1992 to December] 992 (I) and December 1992 to May 1993 (II)

9 Raw Data of Willow Survival 68

10 Raw Data of Rebar Erosional Measurements 69 vi

LIST OF FIGURES

Figure Page

1 Topography of the Watershed for the Charleston 2 Side-Channel Reservoir

2 Map of Locations of Active Shoreline Erosion 4

3 Shoreline Erosion - South Shore of Reservoir 5

4 Shoreline Erosion - Southwest Shore of Reservoir 6

5 Shoreline Erosion - Northwest Shore of Reservoir 7

6 Shoreline Erosion - North Shore of Reservoir 8

7 Willow Cutting Preparation 17

8 Location of Experimental Sites 20

9 Willow Survival - Sites 1-4 Combined 42

10 Willow Survival by Site - May 1992, October 1992, 43 and May 1993

11 Willow Survival by Row - Site 1 50

12 Willow Survival by Row - Site 2 51

13 Willow Survival by Jfow - Site 3 52

14 Willow Survival by Row - Site 4 53

15 Average Monthly Water Levels for the Charleston 59 Side-Channel Reservoir vii

LIST OF PLATES

Plate Page

1 Volunteer Geology Work Crew iii

2 Erosion Control Matting Installation along Site 4 25

3 Lopping of WiJJow Shrubs on the Side-Channel Dike 25

4 Cutting Preparation by Volunteer Biology Work Crew 27

5 Willow Planting on Section 2c 27

6 Site 1, Sections 1w, le, 1mw, and lm - 4/9/92 32

7 Site 2, Sections 2m and 2mw - 419192 32

8 Site 3, Sections 3c and 3w - 419192 34

9 Site 4, Sections 4w and 4c - 419192 34

10 Adventitious Growth - 4/23/92 36

11 Adventitious Root Growth - 516193 36

12 Development, Section 3mw - 4/23/92 39

13 Shoot Development, Section 4w - 8/11/92 41

14 Shoot Development Prior to Abscission, Section 1 w - 41 1017192

15 Section 2mw Buried Following a Tree Landslide - 46 515193

16 Section 1w after High Reservior Levels - 515193 46

17 Section 3mw with High Survival - 5/5/93 48

18 Exposed Rebar on Section 4c after l Iigh Reservoir 48 Levels - 5/5/93 1

LITERATURE REVIEW

In all reservoirs, the storage volume is a critical determinant of their

efficacy, and therefore, the utility of a reservoir diminishes as its storage

capacity is reduced (Mahmood 1987). Reservoirs trap a part of the sediment

load transported by incoming sources, and experience a continual reduction of storage volume. The rate at which siltation occurs varies with a reservoir's

design and the magnitude of the sediment load (Mahmood 1987). The sediment load may be produced either by sheet erosion of the surrounding land or by erosion of the banks of the reservoir itself. Shoreline modification in a reservoir is likely to be greater than in a comparable natural lake because the annual drawdown exposes a larger area to the effects of shore processes

(Baxter 1977). Sediment pollution has been ranked as the most serious problem of Illinois lakes (Sefton 1978), most of which are artificial.

Municipalities utilizing reservoirs are discovering that the quality and capacities of their water supply are diminishing because of eutrophication and sedimentation (Stout 1981).

The Charleston Side-Channel Reservoir (CSCR), located in Coles

County, IL, serves as a water supply and recreational area for the City of

Charleston (Figure 1). It is the only potable water source for the city. The

CSCR was constructed (1979 to 1982) to solve sedimentation problems occurring in the existing Lake Charleston and to increase the raw water storage volume (City of Charleston 1992). It is clear from erosional measurements and visual observations that the CSCR has and is experiencing shoreline erosion at an alarming rate. 2

1000 0 1000 2000 - -- Feet N

Figure 1. Topography of the Watershed for the Charleston Side-Channel Reservoir (contour interval 20 feet) (City of Charleston 1992) 3

The U. S. Department of Agriculture Conservation Service (USO/\

SCS) prepared sediment loading estimates for the CSCR in 1990. The total

estimated amount of sediment delivered annually from the watershed to the

CSCR is 2758 m tons (3,064 tons). Of this, shoreline erosion is estimated to

constitute 900 m tons (1,000 tons)/yr or 32.6'Jlo. J\t this rate, shoreline erosion

is the second largest source of sedimentation. Ravine stormflow is a larger

source contributing 1214 m tons (1,349 tons)/yr of sediment to the reservoir.

(USDA SCS 1990a)

The southern, western, and part of the northern shorelines are actively

eroding and are characterized by steep, unvegetated slopes (City of

Charleston 1992). These shoreline areas were mapped by members of the

Eastern Illinois University Geology/Geography Department in 1988. Distance

along the shore and height of erosional cliffs were measured (Figures 2-6). The perimeter of the shoreline was also classified as non-erodible, low

erosion, and high erosion areas (Table 1 ). The highest erosional cliffs are

located on the south shore, reaching heights of 15 m (50 ft). Here, strong

northerly winds combined with north-south orientation of the long axis of the lake create wave action which undermines shoreline cliffs (Gutowski et al.

1991 ). Other areas with cliff heights reaching 6.1 m (20 ft) include the southwest, northwest, and north shore.

The process of shoreline erosion in the CSCR is primarily attributable to wave action (Gutowski et al. 1991). Considering a maximum estimated fetch of over 1300 m ( 4500 ft), the predicted wave height for an 80 km/h (50 mph) wind using an SCS guide is 0.6 m (2 ft) (USO/\ SCS 1982 in McComas 1985).

Boat traffic in the CSCR also contributes to wave production. The wave activity undercuts poorly consolidated materials. Higher slopes lose their basal support as the cliff retreats and the upper material undergoes mass movement 4

LOCATIONS OF SHORELINE EROSION

Lakeview Park

Drowned

Charleston Side-Channel Reservoir

®

IO ©

N R I ver Pump Houu ·~ .. 500 1000 1500 Scale In Feet I Lake depths In feet below surface - Surface Datum 588' Surveyed 8-88 by: Or. Vincent Cutows1d, EIU Ceolo9y/Ceo9r.aphy · Kr. Huk Christ, EIU [nv(roM\enUI Blolo9y Hr. Robert Young, EIU [nvlron~nul Biology

Figure 2. Map of Locations of Active Shoreline Erosion (City of Charleston 1992) HEIGHT OF EROSIONAL CLIFF ABOVE WATER SURFACE

South Shore of Reservoir

a; 0 ~-- / - "-,,.._,...,--'--7- ::::-"' °'

~:l (/) a; (ij s: Q) > 0 fa 1!!"~~1~~~~~~

13 600 800 FEET 1OOO 1200 0 B C .E ·a;O> J: ~~~~~~-;I~ 1200 1400 FEET 1600 1800 D c

Figure 3. Shoreline Erosion - South Shore of Reservoir (City of Charleston 1992)

\J1 HEIGHT OF EROSIONAL CLIFF ABOVE WATER SURFACE

Southwest Shore of Reservoir

so~:<=-~------=~~------'==~=-- --=------=-====---==-~::=:-.;.:;.__ __::- -=::----:=" ~~ ------= ~--:----====------=--:---==--===--..: -==s==------==- ~---- ·_--::_-----===:::_____,__-====-~- -== :~~,~~ &: i" g. 0 'E20Q FEET 400 600 i F ::I

Figure 4. Shoreline Erosion - Southwest Shore of Reservoir (City of Charleston 1992)

O'I HEIGHT OF EROSIONAL CLIFF ABOVE WATER SURFACE

Northwest Shore of Reservoir

-~==i Q) g

~:::s ...

Figure 5. Shoreline Erosion - Northwest Shore of Reservoir (City of Charleston 1992)

-...J HEIGHT OF EROSIONAL CLIFF ABOVE WATER SURFACE

North Shore of Reservoir

60 ---·•• n i" g.

~::I Cl.I :ll::,,;-I~--~;~~i:-;,;_~?5~c''-1.~C''t[ct'01;r;'.·1c.c-'.-,~~ a; iii o L 200 400 - soo. 3: ~ M Q)

60 ~ - -- 40 --= ----~--=~~------~-=--- tS =- 0 .E ·a;C> ::i: sou 1000 1200 FEET N

Figure 6. Shoreline Erosion - North Shore of Reservoir (City of Charleston 1992)

0) 9

Table 1. Erosional Classification of the Perimeter of the Charleston Side­ Channel Reservoir

Shoreline Classification Shoreline Length Percent of m (ft) Total

Non-Erodible: 34 Dike 1220 (4000) Raw Water Intake Apron 213 (700) Dam 122 (400) Total 1555 (5100)

Low Erosion: 27 West Shore (H to I) 610 (2000) Northwest Comer 91 (300) Northeast Shore 518 (1700) Total 1220 (4000)

High Erosion: 39 South Shore (A to D) 518 (1700) West Side of Dam 122 (400) Southwest Shore (E to H) 488 (1600) Northwest Shore (I to K) 305 (1000) North Shore (L to N) 305 (1000) Total 1738 (5700)

(City of Charleston 1992) 10 into the CSCR (Gutowski et al. 1991). Areas of high erosion constantly receive new sediments from the glacial till and bedrock shoreline. Another cause of shoreline erosion is tree tip-ups along the cliffs (City of Charleston 1992). When large trees along the edge fall into the CSCR, large amounts of soil are carried with the root ball and further expose easily erodible material. Sedimentation in the CSCR as a result of shoreline erosion causes problems in three main areas: reduction of reservoir volume, increased nutrient loading, and increased turbidity of the water. A decrease in the water volume capacity is a direct effect of sedimentation. Deep water areas have been filled primarily from shoreline erosion and, consequently, the maximum depth has gone from 6.1 m (20 ft) in 1982 to 4.9 m (16 ft) in 1988 (City of Charleston 1992). Other direct problems include: loss of real estate, burial of water treatment plant intake ports in the northwest comer of the CSCR, and the erosion of City property lines into neighboring properties (City of Charleston 1992). Along with sediment, other substances introduced into the reservoir include phosphorus and nitrogen, two important lake or reservoir nutrients. External nutrient loading can increase eutrophication rates in bodies of water by creating favorable conditions for algal blooms. Problems associated with algal blooms are bad taste and odor, trihalomethane problems in water treatment, low dissolved oxygen levels for fish, and increased turbidity from live and dead algae. Total phosphorus loading from shoreline erosion was estimated at 637 kg (1400 lbs)/yr (City of Charleston 1992). This value showed shoreline erosion to be the largest contributor of external phosphorus loading. Nitrate and ammonia loading rates from shoreline erosion were not available. Turbidity, or clarity of the water, is indirectly problematic as well. The eroded sediments in combination with algal stimulation from nutrient loading 11 cause cloudiness of the water. The CSCR has been a participating lake in the IEPA Volunteer Lake Monitoring Program (VLMP) since 1982 in which Secchi disk transparency is one parameter monitored. There was a significant difference between the mean 1990 CSCR transparencies and the mean for 1982 and 1983 (p < 0.05). 20 cm (8 in) difference was apparent between 1982 (53 cm (21 in)) and 1990 (33 cm (13 in)) (Burns 1991). Based on Secchi disk transparencies, total phosphorus, and chlorophyll a concentrations, the CSCR is currently classified as a hypereutrophic (Carlson's TSI=74 average) body of water (City of Charleston 1992). High turbidity levels block the penetration of light through the water column and suppress the growth of submersed aquatic macrophytes. This, in combination with disruptive wave action, causes the characteristic barren shoreline of the CSCR. A macrophyte survey of the CSCR, conducted in 1989 by Dr. John Ebinger from Eastern Illinois University's Department of Botany, revealed the absence of submersed aquatic macrophytes (City of Charleston 1992) (Table 2). Without the protection of vegetation, the reservoir shoreline is subjected to high rates of erosion. As a part of Clean Lakes Program Phase II (remediation), methods to control shoreline erosion have been proposed. In addition to the more traditional riprap and gabions, the city has considered selective tree removal, reduced water levels, sea walls, raft wave barriers, and revegetation of eroded areas. One potential technique of protecting eroding banks is stabilization using vegetative cuttings. Live cuttings are taken during the dormant season and planted singly, in bundles, or in other biotechnical combinations into the unstable bank. After the cuttings root and grow, they produce a dense, 12

Table 2. Vascular Plants of the Charleston Side-Channel Reservoir

Submersed Aquatic Macrophytes: None

Floating Aquatic Macrophytes: Duckweed (Lemna minor L.) Water Meal (Wolffia columbiana Karst.)

Emergent Aquatic Macrophytes: Water Willow (Justicia americana L.) Creeping Primrose Willow (Ludwigia peploides L.) Water Smartweed (Polygon um amphibium L.) Swamp Dock (Rumex verticillatus L.) Bulrush (Scirpus atrovirens Willd.) Bulrush (Scirpus tabernaemontanii K. C. Gmel)

Shoreline Vascular Plants: Buttonbush (Cephalanthus occidentalis L.) Privet (Ligustrum obtusifolium Sieb. & Zucc.) Sycamore (Platanus occidentalis L.) Cottonwood ( deltoides Marsh.) Multiflora Rose (Rosa multiflora Thunb.) Sandbar Willow (Salix interior Rowlee) Crack Willow (Salix fragilis L.) Black Willow (Salix nigra Marsh.)

Herbaceous Plants: Swamp Marigold (Bidens aristosa [Michx.] Britt.) Nodding Bur Marigold (Bidens cernua L.) Common Beggar-tick (Bidens frondosa L.) Sedge (Carex comosau Boott). Sedge (Carex vulpinoidea Michx.) Fog-fruit (Phyla lanceolata [Michx.] Greene) Reed Canary Grass (Phalaris arundinacea L.) Pale Smartweed (Polygon um lapathifolium L.) Common Arrowleaf (Saittaria latifolia Willd.) Bulrush (Scirpus atrovirens Willd.) Bulrush (Scirpus tabernaemontanii K. C. Gmel.)

(City of Charleston 1992) 13 vegetative growth above the ground surface and a dense root mass in the subsoil, protecting the bank from erosion (Kohnke and Boller 1989). Vegetative material protects the bank in several ways. Living root systems hold soil in place, providing immediate bank stability and increased soil strength. Waterflow and wave velocities are reduced due to increased shoreline roughness (Heyer 1991). The vegetation, because of its ability to yield and rebound under stress, acts as a buffer against abrasive transported materials and directs flow velocity away from the bank (USDA SCS 1990b). Plants remove excess moisture from the banks, lowering the saturation line and reducing slippage (Kohnke and Boller 1989). Vegetation also causes deposition of sediment and nutrients from runoff or in-lake sources and thereby re-establishes the bank (Heyer 1991). These vegetative buffer zones are very effective in both the short and long term in controlling sediment and nutrient pollution (White 1991). Besides erosion prevention, natural vegetation provides additional benefits yet few detractants. The aesthetic quality of the shoreline is enhanced, especially after new types of vegetation become established. Detritus formed from the which have fallen into the water body play an important role as a food source for aquatic invertebrates, which in tum are eaten by several fish species (Reiser and Bjornn 1979 in McCluskey 1983). Well developed stands provide cover and habitat for aquatic organisms by way of shading and overhanging branches (McCluskey 1983). While fish populations could be stimulated by shoreline growth, potential bank fishing spots may be reduced. Willows are most often the cutting material of choice for bank stabilization projects. Willow transplants are recommended because they are often locally available and acclimated, easily established, relatively 14

inexpensive to plant, provide good stability for the site, are adaptable to moist conditions, and grow rapidly (Lamb 1915; McCluskey 1983; Conroy and Svejcar 1991). Hardly any other genus of a woody nature compares to Sali:c in the ability to be vegetatively propagated by cuttings (Chmelar 1974). Ecologically, willows are known to provide good habitat with rich associations of flora and fauna, especially insects (Sommerville 1992). They also act as a pioneer species, improving the nutrient status and physical structure of the poorest (Stott 1992). Dogwoods, sycamore, poplars, cottonwoods, buttonbush, river birch, forsythia, certain red maples, and plum have been reported as acceptable woody species (USDA SCS 1990b; Kohnke and Boller 1989; Platts 1987). However, only willows and cottonwoods generally do not require growth hormone treatment for rooting (USDA SCS 1990b). Some species of willows have preformed root primordia, which are initiated on stems during their first growing season as part of normal ontogenetic development (Carlson 1950 and Haissig 1974 in Krasny et al. 1988). The presence of these beginnings seems to be important in enabling the cutting to form adventitious which grow quickly. Species without preformed root primordia root poorly or not at all (Platts 1987). The ability to form adventitious roots enables riparian willows to survive and grow under saturated soil conditions and is an important adaptation for plants subject to periodic flooding (Krasny et al. 1988). Willows growing in saturated soils also form pink aerial root tips, thought to enhance root aeration (Gill 1970 in Krasny et al. 1988). Evidently, growth-inducing substances are stored in the stem tissue, particularly at the growing point (the bud). One such substance, called "rhizocaline" by F. W. Went, is stored in the buds and moves to the basal cut, where it induces root formation (Schiechtl 1980). Since root formation does 15

not occur on willow cuttings without buds, it has been concluded that with greater numbers of buds, root formation is likely to be better (Schiechtl 1980). Michniewicz and Kriesel (1972) pointed out that the adventitious roots of willow cuttings are the sites of gibberellin synthesis, important in the processes of root growth. Success of revegetation is increased when certain considerations are taken when planning stock site and time of project. Planting projects should take place during dormancy, preferably in early spring prior to noticeable bud

swelling (Schiechtl 1980; Gray and Leiser 1982; USDA SCS 1990b). Densmore and Zasada (1978) found that rooting was more rapid in stems collected in the spring. Soil moisture levels are high at this time and cuttings are allowed enough time for root development prior to another dormancy (McCluskey 1983). Utilization of local willow stocks from similar environmental conditions as the treatment site will improve survivability of cuttings (McCluskey 1983). Using readily-rooting willow species insures good growth and increases cutting survival. In a study involving rooting capacity of 107 species of Salix, most species rooted readily and were characterized by a diffuse type of rooting instead of only basal (Chmelar 1974). Cutting size depends on availability, species used, and the treatment site. Schiechtl (1980) stated that the length of the roots increases in relation to the length and volume of the cutting. Larger volume provides greater food reserves and greater amounts of growth hormones. Platts (1987) related that stems 1.0 cm (0.4 in) or larger in diameter survive much better than smaller dimensions, while a Lake Tahoe Basin study had best results with cuttings 1.3 cm (0.5 in) to 1.9 cm (0.75 in) thick (Grey and Leiser 1982). Lamb (1915) stated that the smaller the cutting, if protected from mechanical injury, the less chance for disease. The age and 16 size of the stem, however, are of less importance to readily rooted willow species than to poorly rooted selections (Chmelar 1974). Certain guidelines for preparation and planting of cuttings should be adhered to as well. The term "cuttings" usually includes material 1.3 cm (0.5 in) to 2.5 cm (1.0 in) in diameter and proper lengths vary from 0.3 m (1 ft) to

0.9 m (3 ft), depending on site conditions. It is recommended that a terminal bud scale scar be located within 2.5 cm (1 in) to 10 cm (4 in) of the top of the cutting. The greatest concentration of shoots and their strongest ones occur here. At least two buds and/or bud scars should be above the ground after planting. To aid in orienting the stems for planting, the terminal exposed end should be cut horizontally while the basal end should have a 45 degree cut (Figure 7). All lateral branches are then trimmed in order to reduce excessive leafing and flower production. All cuts made with lopping shears, axes, or pruners should be clean with unsplit ends. To prevent the cuttings from drying out, bundles of willows are placed in buckets of water before being transported to the site. Cuttings should be planted as soon as they are prepared. If time is limited, they can be submerged in very cold water, wrapped in moist burlap, or stored in plastic garbage bags and kept in the dark at near freezing temperatures. If cuttings cannot be manually pushed into the soil, some type of metal pole may be used to make holes. Spacing and depth of planting will vary according to soil conditions. Usually one­ fourth to one-half of the stem should remain exposed. Adequate stem burial facilitates proper moisture extraction for root development, insures greater rooting surface, and minimizes water loss due to transpiration. (Lamb 1915; Schlecht! 1980; Gray and Leiser 1982; McCluskey 1983; Platts 1987; USDA SCS 1990b) 17

FLAT TOP END--.---

TERMINAL BUD SCALE SCAR----

~---~LAT~RAL BUD

·-----LATERAL BRANCH REMOVED

"'------TAPERED BOTTOM END

Figure 7. Willow Cutting Preparation 18

The use of willow cuttings for bank stabilization was proposed as the most ecnomically feasible treatment for shoreline erosion by the Technical Advisory Committee for the Diagnostic/Feasibility Study of the Charleston Side-Channel Reservoir. Areas of high and low erosion were targeted for future willow treatment in Phase II of the Clean Lakes Program. Although it was thought that willow establishment was highly plausible along the reservoir's shoreline, the degree of bank protection was unknown. The purpose of this study was to determine the feasiblity of such action for the CSCR, the extent of bank stabilization success, and to outline an efficient method of treatment for further planting if considered successful. 19

METHODS AND MATERIALS

While most of the bank stabilization study lasted from February 1992 to May 1993, preparation and planning occurred during the Fall and Winter of 1991. Planning involved shoreline evaluation, site designations, material acquisition, volunteer organization, and permit application. A permit from the U.S. Army Corp of Engineers (USAC) was applied for by the City of Charleston in order to gain permission for shoreline experiments. However, the USAC deemed permit application unnecessary for the proposed project. Four sites around the CSCR were designated as test areas based on shoreline direction, bank uniformity and ease of working area (Figure 8). Only western and southern shorelines were designated with sites. The entire eastern side of the CSCR is lined with riprap. The northern side was not selected due to property boundary limitations, poor accessibility and hard substrates. Each of the four sites was measured and designated as follows. Each site consisted of 24 lineal meters (80 ft) of shoreline, divided into four 6.1 m (20 ft) sections. Each site contained an untreated control section (c), a matting section (m), a section of willow treatment alone (w), and a section with willow and matting treatment in combination (mw) (Figure 8). Each site was then cleared of logs and debris to maintain uniformity and lessen erosional bias. Experimental field procedures consisted of reinforcement bar ("rebar") placement, matting installation, and willow staking, in that order (Table 3). Volunteers from Eastern Illinois University Departments of Geology/Geography, Botany and Zoology were organized into crews. Geology crews generally prepared sites, drove rebar, and secured the matting 20

Plant MAP OF RESERVOIR DEPTHS

Lakeview Park 4C 4w 4m 4mw 3mw 3m 3w 3c

Charleston Side-Channel Reservoir

10

N

1000 1500 1 Scale in Feet Lake depths in feet below surface - Surface Datum 588 1

SurveyW 8-88 by: Dr. Vincent Gutowski, [IU Ceology/'""9r•plly · ftr. n.rk Christ, EIU [nvir.,...nt•I Biology "'· "*rt Youf19, EIU Emrlr-nt•I liology

Figure 8. Location of Experimental Sites 21

Table 3. Dates of Rebar, Matting, and Willow Placement for Sites 1-4

Rebar/Matting Willows Site 1 02-22-92 02-22-92 Site 2 02-16-92 02-26-92

Site 3 02-08-92 02-16-92

Site 4 02-08-92 02-16-92 22 fabric. One biology crew prepared willow cuttings and another crew planted the cuttings. Rebar poles were used as a basis to monitor erosional rates along the banks. 1.3 cm (0.5 in) diameter, 6.1 m (20 ft) long rebar poles were cut into approximately 86 cm (34 in) segments. With sledgehammers, these poles were driven perpendicular into the side of the banks, flush with the cliff surface. Vertical spacing was 0.9 m (3 ft), and the number of rows was dependent upon the height of the bank at each site. The lowest row of rebar was driven into the bank/shelf interface which approximated the average water pool elevation. Column spacing usually consisted of 1.2 m (4 ft) intervals, but occassionally 1.5 m (5 ft) or 1.8 m (6 ft) intervals were required due to buried rocks.

It was thought that the cuttings might need temporary stabilization in the form of a fabric. Erosion control matting, obtained from North American Green, came in rolls measuring 25.5 m (83.5 ft) by 2.0 m (6.5 ft). The material consisted of a layer of straw and coconut fibers sandwiched between two layers of polypropylene, crosshatched line. 15 cm (6 in) metal staples were used to secure the fabric to the soil. The matting was rolled out onto the designated site and cut. A 15 cm (6 in) trench was dug along the bottom edge of the matting. About 46 cm (18 in) of matting was then stapled and buried in the trench. (A trench was not dug at site 1 or site 2 due to muddy conditions and rocky substrates, respectively). The top 30 cm (12 in) of fabric was rolled and stapled securely to the bank. The stapling pattern on the 1.5 m (5 ft) wide strip of exposed matting was generally in 30 cm (12 in) wide rows by 60 cm (24 in) wide columns with heavier stapling on the top and bottom edges

(Plate 2). 23

Willow cuttings were taken from a stand of sandbar willows (Salix

interior) on the eastern side of the side-channel dike. These trees were young (up to four years old) and less than 5 m (16 ft) tall. Large numbers of acceptable cuttings were available due to the coppicing effect of previously cut shoreline willows. Healthy looking willows with stems from about 1.0 cm (0.38 in) to 2.5 cm (1.0 in) in diameter were cut at the base with lopping shears (Plate 3). A transect cut was made with a sharp hatchet 5 cm (2 in) to 13 cm (5 in) above an annual scar. A diagonal cut was then made about 0.9 m (3 ft) below the top cut (Figure 7). To prevent dehydration during transport, these cuttings were placed with their bottom end immersed in buckets of water (Plate 4). Before planting a cutting, a hole 36 cm (14 in) to 46 cm (18 in) deep was made into the side of the bank using custom-made willow stickers and poles no more than 2.5 cm (1 in) in diameter. The cutting was stuck by hand into the hole (with the flat top end pointing up) and secured by gently tamping the soil around the branch, forcing air pockets out (Plate 5). All willows were planted on the same day as they were cut except for those at site 1. Due to limited workers and time, excess cuttings were kept in bundles and submerged in the reservoir or kept in buckets of water and used at site 1 nearly a week later. Data collection occurred in late Spring, Fall, and Winter of 1992 and late Spring of 1993. Sites were surveyed on May 12, 1992; October 7, 1992; and May 5, 1993 for willow survival. Numbers of willows living, dead, and missing were recorded. Rebar measurements in 1992 were taken on May 19 (site 3), May 20 (site 4), May 26 (site 2), and May 28 (site 1) for the first erosional recordings and on December 11 (sites 3 and 4) and December 12 (sites 1 and 2) for the second erosional recordings. Rebar measurements in 24

Plate 2. Erosion Control Matting Installation along Site 4

Plate 3. Lopping of Willow Shrubs on the Side-Channel Dike 25 26

Plate 4. Cutting Preparation by Volunteer Biology Work Crew

Plate 5. Willow Planting on Section 2c 27 28

1993 occurred on May 5 for all sites. Number of centimeters of rebar exposed or buried were measured. Buried poles were located using a metal detector and long screwdriver. At the time of planting, soil samples were taken along the banks and processed for sediment analysis. Water levels for each willow row were determined using a leveling pole. Time at or under the water surface could be assessed by using the daily reservoir level logbook at the Charleston Water

Treatment Plant. All statistical analyses were performed using NW A Statpak ver.4.11 (1990). 29

RESULTS AND DISCUSSION

Site Characteristics An understanding of the characteristics of each site is important to appreciate the results produced from this project. Experimental sites varied according to location, cliff height above normal pool, and sediment type (Table 4). A representative photograph taken one month after planting is also given although not all sections are shown for each site (Plates 6-9). Sites 1 and 2 can generally be classified as the most extreme cases of shoreline erosion in the reservoir. Each has high erosional cliffs, a larger percentage of loosely consolidated sediments, and terraces (the area immediately above the erosional cliffs) which are steeply sloped. Sites 3 and 4 are less severe, exhibiting small cliffs, more equal sediment consistancy, and more gradually rising terraces.

Root and Shoot Development The cuttings broke dormancy during the first half of March 1992 but did not produce noticeable shoots until nearly a month later. From one to sixteen lateral branches were observed with an average of six per cutting. The shoots usually were clustered around the terminal bud scale scar. A cutting was uprooted on April 23 to observe adventitious root growth (Plate 10). A diffuse type of rooting was evident, confirming Salix interior as a readily­ rooted species (Chmelar 1974). Uprooted cuttings were observed again on May 6 revealing extensive root growth (Plate 11). Table 4. Physical Characteristics of Sites 1-4

Shore Cliff Height Sediment Analysis Site location m (ft) N % Sand %Silt % Clay Plate 1 south 4.5-7.5 (15-25) 10 42.3 +/- 4.1 40.0 +/- 2.7 17.7 +/- 2.3 6

2 southwest 2.5-4.5 (8.0-15) 10 39.6 +/- 2.6 43.5 +/- 2.5 17.9 +/- 1.9 7

3 west 1.0 (3.3) 8 35.0 +/- 5.6 37.1 +/- 7.0 27.9 +/- 9.1 8

4 west 2.0 (6.6) 8 30.6 +/- 7.3 35.5 +/- 4.6 33.9 +/- 4.6 9

w 0 31

Plate 6. Site 1, Sections lw, le, lmw, and lm - 4/9/92

Plate 7. Site 2, Sections 2m and 2mw - 4/9/92 32 33

Plate 8. Site 3, Sections 3c and 3w - 4/9/92

Plate 9. Site 4, Sections 4w and 4c - 4/9/92 34 35

Plate 10. Adventitious Root Growth - 4/23/92

Plate 11. Adventitious Root Growth - 516193 36 37

Willow Survival Willow survival data of the three recording dates (May 12, 1992; October 7, 1992; and May 5, 1993) were converted to percentages. Propagation success in the Spring was quite high (Plate 12) and was followed by very acceptable survival values in the Fall (Plates 13 and 14). Out of 477 cuttings planted, 442 (92.7%) had produced adventitious shoots and were still living by May 12. By October 7, 380 (79.7%) were considered viable. By the following year, however, the number survived was reduced to 141 (29.6%). These willow totals were further divided according to presence or absence of matting treatment to determine whether a difference existed between their respective survival ratios (Figure 9). Although mat/willow (mw) totals did exceed the willows alone (w) totals on each date, visually, the differences are not outstanding (1.9%, 8.3%, and 10%). Statistically, (using the Fisher Exact Test, one-sided significance level=0.05), w treatment totals and mw treatment totals were not significantly different in the spring. However, October totals (p=0.0224) and May 1993 totals (p=0.0090) were. Individual site survival with respect to w and mw sections was examined for each data recording event as well (Figure 10). Most sites were doing extremely well almost three months after planting. It should be noted again as a testimony to S. interior's propagative hardiness that the cuttings used for site 1 were stored for one week prior to planting. Only section 2w showed a minimal decrease as a result of bank scouring along the two bottom willow rows. Five months later, sites 1, 3 and 4 were still above 80% survival; whereas, site 2 showed an increased decline in willow numbers. May 1993 site percentages reveal the devastating effect that high water levels had on the established willows. Site 2 was practically destroyed (Plate 15) and site 1 38

Plate 12. Shoot Development, Section 3mw - 4/23/92 39 40

Plate 13. Shoot Development, Section 4w - 8/11/92

Plate 14. Shoot Development Prior to Abscission, Section lw - 10/7/92 41

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I

I 42

100

90

80

70

60 survival (%) 50

40

30

20

10

0 May-92 Oct-92 May-93

Figure 9. Willow Survival - Sites 1-4 Combined 43

May-92

100 90 80 70 60 survival(%) 50 (0 30 20 10 0 1 2 3 4 site

Oct-92

100 90 80 70 60 survival(%) 50 (0 30 20 10 0 1 2 3 4 site ii'lilmw l•w May-93

90 80 70 60 50 survival(%) (0 30 20 10 0 1 2 3 4 site

Figure 10. Willow Survival by Site • May 1992, October 1992, and May 93 44 suffered heavy losses (Plate 16). Site 4 fared somewhat better than site 1 (Plate 18), while site 3 willows still showed high survival (Plate 17). Statistical analyses were performed on individual sites to determine whether the matting contributed to an increase in survival. There was no significant difference for sites 1, 3, and 4 for both May and October of 1992. Site 2 did show a significant difference between treatments for both May (p=0.0007) and October (p=0.0301). At both times the matting treatment provided a 20% survival advantage over willows alone. May 1993 analysis showed no statistical difference between site 1 and site 2 wand mw survival ratios. Both site 3 (p=0.0317) and site 4 (p=0.0025) had mw values significantly larger than w values. The difference between the two treatments averaged 23%.

Death Patterns Records of intact deaths and uprooted deaths (Table 5) as well as survival for each row at each site (Figures 11-14) were kept to investigate death patterns. Row 1 is the top row of cuttings and row 4 is the bottom. Section 1w contained more than four rows, so actually rows 2-5 were used in comparison to section lrnw. Data for the second year is not given because of the difficulty in determining row designation of the remaining willows after spring rains. By May 1992, 34 cuttings had not survived. This number increased to 96 by October. At both times of the year, more than half of the loss was recorded as uprooted, 79% and 59% respectively (Table 5). During most of the first year, uprooted deaths were caused by wave erosion along the shelf of the shoreline when reservoir levels were still below the cliff/shelf interface (Table 6). The effect can be seen in the decreased survival of the willows planted on the shelf of site 1 (Figure 11, rows 3 and 4) 45

Plate 15. Section 2mw Buried Following a Tree Landslide - 5/5/93

Plate 16. Section 1w after High Reservoir Levels - 5/5/93 46 47

Plate 17. Section 3mw with High Survival - 515193

Plate 18. Exposed Rebar on Section 4c after High Reservoir Levels - 515193 48 49

Table 5. Uprooted Deaths versus Intact Deaths by Section May and October 1992

lw lmw 2w 2mw 3w 3mw 4w 4mw May-92 Uprooted 8 5 7 0 0 0 2 5 Intact 1 1 3 0 0 1 1 0

Oct-92 Uprooted 13 11 19 6 0 0 4 4 Intact 1 1 10 12 9 3 2 1 50

May-92

100 90 80 70 60 survival (%) 50 40 30 20 10 0 1 2 3 4 row jaw Elmw I

Oct-92

100 90 80 70 60 survival(%) 50 40 30 20 10 0 1 2 3 4 row

Figure 11. Willow Survival by Row - Site 1 51

May-92

100 90 80 70 60 survival(%) 50 40 30 20 10 0 1 2 3 4 row lllw Glmw I

Oct-92

100 90 80 70 60 survival(%) 50 40 30 20 10 0 1 2 3 4 row

Figure 12. Willow Survival by Row - Site 2 52

May-92

100 90 80 70 60 survival(%) so 40 30 20 10 0 1 2 3 4 row I lmw ffilmw I

Oct-92

100 90 80 70 60 survival (%) so 40 30 20 10 0 1 2 3 4 row

Figure 13. Willow Survival by Row - Site 3 53

May-92

100 90 80 70 60 survival (%) 50 40 30 20 10 0 1 2 3 4 row I llw mlmw I

Oct-92

100 90 80 70 60 survival(%) 50 40 30 20 10 0 1 2 3 4 row

Figure 14. Willow Survival by Row - Site 4 54

Table 6. Water Levels of Willow Rows and Percentage of Time at or below Water Level

Water Level• Willow Rows by Section % Time at or below Water Level cm in lw lmw 2w 2mw 3w 3mw 4w 4mw 3/92-5/92 3/92-10/92 3/92-5/93 99 39 1 0 0 0 81 32 2 0 0 0 76 30 1 0 0 0 61 24 1 0 0 0 56 22 3 0 0 0 53 21 2 0 0 0 48 19 1 0 0 0 41 16 1 0 0 0 38 15 4 0 0 0 36 14 1 0 0 0 30 12 3 2 0 0 0 28 11 2 0 0 0 18 7 1 0 0 0 13 5 1 0 0 2 10 4 5 3 2 0 0 3 5 2 2 0 0 10 3 1 2 0 0 13 0 0 2 0 2 20 -3 -1 3 0 6 24 -5 -2 3 3 5 15 35 -8 -3 4 4 4 10 20 42 -10 -4 6 17 31 49 -13 -5 3 3 19 38 56 -15 -6 4 33 69 n -18 -7 4 4 60 81 79 -20 -8 7 5 4 64 86 82 -23 -9 8,9 6 76 91 87 • above or below average pool SS

and site 2 (Figure 12, rows 3 and 4). Sites 3 and 4 were exposed to longer fetches on the western side of the reservoir and were buffered by the Justicia americana, and therefore, did not experience the survival decrease on the bank shelf (Figures 13 and 14). Based on row patterns during the first year, intact deaths can likely be attributed to desiccation. Of the very few recorded dead, intact willows the first year, most of these occurred in sections 2w, 2mw, and 3w (Table S). Row 1 of these three sections contained 87% of the intact deaths (Figures 12 and 13, October 1992). Obviously, the willows lacked the moisture needed for growth and survival in well-drained cliff areas.

Erosional Measurements May 1993 raw rebar data were averaged for each of the four sections of each site (Table 7). Mean values for May and October of 1992 are not given because erosional values during the first year did not reveal much. Some of the rebar poles which were buried by eroded material from above were not found, and hence, those recorded as buried were given a zero erosional value. General observations can be made from the erosion data. First, erosional rates were more severe from December 1992 to May 1993 than from May 1992 to December 1992. For example, differences between mean control values, signifying normal erosional activity, were almost always greater for the latter time period (Table 8). Only sections 2c and 4c at the 0 m level had smaller mean differences which could have been underestimated from sedimentation from above. The sharp decline in willow survival at the May 1993 recording as compared to the October 1992 recording confirms an increase in the erosional process. The increased erosion is explained by the reservoir level during the year. 56

Table 7. Mean Exposed (+) or Buried(-) Centimeters of Rebar (Standard Error) - May 1993

Site Rebar Level c w mw m

1 0.9 m 5 (4) 20 (5) 9 (9) 17 (3)

2 1.8 m 11 (6) 1 (3) 0.9 m 5 (1) 5 (9) buried 7 (2) 0.0 m 19 (8) 18 (4) buried 30 (4)

3 0.0 m 17 (1) 2 (2) 0 (0) 0 (1)

4 0.9 m 27 (7) 41 (7) 6 (1) 27 (10) 0.0 m 19 (2) 18 (2) 15 (3) 16 (1) Table 8. Differences of Mean Control Rebar Measurements in Centimeters (Inches) Between May 1992 to December 1992 (I) and December 1992 to May 1993 (II)

Rebar Level le 2c 3c 4c m (ft) I II I II I II I II

1.8 (6) 0.3 (0.1) 10.4 (4.1)

0.9 (3) -1.5 (-0.6) 6.1 (2.4) -0.3 (-0.1) 5.6 (2.2) 1.5 (0.6) 19.1 (7.5)

0.0 (0) 15.5 (6.1) 11.2 (4.4) 3.3 (1.3) 28.2 (11.1) 10.9 (4.3) 2.5 (1.0) 58

The high success of the cuttings in the crucial first growing season suggested that long-term success in bank protection was possible. However, with the onset of Spring came excessive precipitation, causing uncontrollable high reservoir levels (Figure 15). Water levels remained high, up to 15 cm (6 in) above normal pool, allowing wave action to erode the more vertically sloping bank. As the lower portion was carved away, the upper material lost its support and experienced mass movement into the reservoir. This movement was very apparent on sections 1w and lm, site 2, and sections 4w and 4c. Section 2mw was totally buried by a large mass of soil and trees which collapsed from above (Plate 15). Site 2mw is an extreme example of excessive erosion not evidenced by the rebar data. Although much bank erosion must have occurred for a whole section to be buried, the graph portrays the section as the least eroded because sediment from the cliff top re-covered exposed rebar. Some rebar poles did receive some sediment deposition, and consequently, the actual erosion occurring is offset somewhat. Sedimentation and cliff height should be kept in mind when reviewing the data. A one-way ANOV A and Student Newman-Keul's Multiple-Range Test (significance level=0.05) were used for each site to test for erosional differences among the three treatments and control. The assumptions related to the ANOVA procedure may be invalid because of the time differential between when the experiment was initiated and the data were collected. Results for sites 1, 2, and 4 suggested no difference in mean erosional values for December 1992. Site 3 (0 m. level) did show a significant difference between the control and each of the three treatment sections (Fca1=28.3, p=0.0000). The treatments did slow erosion to some extent at site 3 but none of the three showed any significant protection over the others. Site 3 in May 59

\

10 1 5 0 •\ -5 i -10 1 .. -15 0 \ -20 ~ -30 ~ ~ q(j) i i i

figure 15. Average MonthlY Water Level• for the Charleston Side-Channel

Reservoir 60

1993 showed the control again as having significantly more rebar exposed than the treatments (Fca1=36.3, p=0.0000), but the treatments were statistically indistinguishable. The difference between the control mean and treatment means increased as well, indicating continued protection during the second period (Table 7). At site 4 (0.9 m.) the matting/willow mean measurements were significantly less than the control and willow sections while the rest were the same (Fca1=4.81, p=0.0166) (Table 7). However, at site 4 (0 m) no difference was observed at all. The matting sections seem to have slowed the erosional process somewhat. As in December 1992, sites 1 and 2 showed no difference in May 1993 among the control and treatment sections, suggesting no significant bank protection by any of the treatments. 61

CONCLUSIONS AND RECOMMENDATIONS

To evaluate the degree of success, two areas of concern must be addressed in a willow cutting project. The first hurdle to overcome is the assurance of establishment of cuttings at a particular site, and the second is a reasonable reduction in the rate of erosion after willow establishment is assured. This project has demonstrated some success in willow establishment but may fail in long-term bank protection under all conditions. The survival percentages in the first year showed that willow cuttings can be established along the shoreline of the CSCR. Willow preparation and planting methods as outlined earlier are valid techniques for completing such a purpose. Salix interior proved to be a riparian species, having diffuse, adventitious rooting, is well-suited to saturated conditions, and is quite capable of being vegetatively propagated. Erosional data analysis from site 1 and site 2 did not suggest a difference between the control and treatment sections one year after planting. Willow survival was drastically reduced on these two sites because of the severity of erosion from wave action after Spring 1993 reservoir levels had dramatically risen. Scouring of the cliff bottoms consequently caused mass sediment slippage from above, further decreasing survival. Extreme cliff heights, longer fetches, and a sandier soil consistency contributed to willow uprootment and lower survival values compared to sites 3 and 4. Willow planting on shoreline areas with cliff heights of about 2 m (6 ft) or less and having a more day-like soil composition (similar to sites 3 and 4) is more likely to provide shoreline stability. Site 3 survival results one year after planting were still acceptable for further planting recommendations. Treatment sections were found to be significantly less eroded than the control 62

section. It was suspected that colonies of Justicia americana increased survival by buffering some shoreline sections of sites 3 and 4. Whether the treatment sections helped fusticia americana establishment is unclear. Site 4 results were not strong enough to warrant further planting without method alterations. Only the matting/willow section of one rebar level was found to lessen the erosional rate over the control. The willows which have survived on sites 3 and 4 will most likely be subjected to further uprooting with future drastic rises in water level. It is recommended that willow planting continue on shoreline sections with small cliff heights but only in combination with a significant wave buffering device or other bank protection option. Overall, the matting fabric is not a worthwhile erosional protection device for willow establishment in the reservoir when considering its degree of success (around 20% increase in survival when significant) over plots without matting and the cost of material and implementation. Only site 2 showed significant benefits during the first year of such protection, yet, both its sections were lost in the following year. The matting did show favorable results in 1993 on the sites with smaller cliffs, but its success was more likely attributable to the wave buffering provided by littoral colonies of water willows.

It is now believed that only a combination of techniques will solve the considerable amount of erosion occurring along the shoreline. Some other erosion prevention/bank protection schemes are being considered by the CSCR Technical Advisory Committee. One structural method which would solve the problem immediately is to riprap the treatment area. Riprapping is simply placement of rock along a shoreline to break wave energy and protect the bank. Riprap can be placed over a naturally or artificially graded slope. Grading a slope would be limited 63 at the CSCR considering the steep, forested slopes bordering the reservoir. A barge would be needed to transport riprap and place it along the shoreline. Besides difficult logistics, cost of riprap treatment, including material, equipment, and labor, is quite expensive. Riprap, however, is being considered for certain specific areas such as the shorelines around the raw and river water intakes and the boat ramp. Other structural methods include construction of sea walls and log-raft wave barriers. Sea walls are rigid structures of sheet pilings driven into the soil and backfilled with soil, forming a barrier between the land and the water. Like riprap, it has a high cost associated with it and is being considered for only the high erosion areas along the southern and western shorelines. A more economically feasible possibility is the log-raft wave barrier. Logs are connected together by chains to form rafts. The rafts are connected in series and are anchored off shore. The intent is to allow the barrier to absorb a portion of the wave energy before it reaches the banks. Currently, a demonstration plot is being developed on the south shore. Another low-cost barrier method suggested is the use of straw bales secured along the shoreline waters to break wave energy and to collect eroded sediment behind it. Both of these methods have not been tested and their merits are unknown. Preventative measures which can decrease shoreline erosion in the CSCR are also being considered. Maintaining reduced reservoir levels during periods of minimal evaporation and plentiful river flow rates has been practiced for the last two years. By keeping waves from undercutting steep cliffs, severe erosion is prevented. Cutting trees which are on the verge of falling along the cliff tops could curtail large scale inputs of sediment into the CSCR. Surveys can be made each year to target trees which need to be cut. 64

Purchasing a siphon was also suggested in order to remove excess reservoir water after heavy precipitation. Excess water could be pumped back into the river downstream. Whenever water is pumped to the water treatment plant for treatment, the reservoir level is decreased somewhat. Three overflow ports linked to Lake Charleston exist, but levels must be very high for any water to drain across. A siphon would not necessarily prevent water levels from rising high after heavy rains but would definitely reduce the amount of time lake levels were high. In combination with a wave barrier, such as the raft method, willow cutting propagation is still a viable bank protection option. Low erosion areas (exemplified by sites 3 and 4) would most likely be protected by such a combination based on the results of this experiment. Wave energy must be dissipated when reservoir levels exceed normal pool in order to prevent undercutting action destructive to willow establishment. High erosion areas (exemplified by sites 1 and 2) will most likely require more costly erosion protection schemes. However, experimental plots consisting of a barrier and willows should be implemented on both low and high erosion areas before resorting to more difficult and costly procedures. 65

LITERATURE CITED

Baxter, R. M. Environmental effects of dams and impoundments. Ann. Rev. Ecol. Syst. 8: 255-283; 1977.

Burns, A. Volunteer Lake Monitoring Program, 1990 - volume I: statewide summary report. Springfield, IL: Ill. Environ. Prot. Agency; 1991. IEPA/WPC/91-61a.

City of Charleston. Clean Lakes Program phase I diagnostic/feasibility study of the Charleston Side-Channel Reservoir. Charleston, IL; 1992. 203 p.

Chmelar, J. Propagation of willows by cuttings. N. Z. J. For. Sci. 4 (2): 185- 190; 1974.

Conroy, S. D.; Svejcar, T. J. Willow planting success as influenced by site factors and cattle grazing in northeastern California. J. Range Manage. 44 (1): 59-63; 1991.

Densmore, R.; Zasada, J. C. Rooting potential of Alaskan willow cuttings. Can. J. For. Res. 8: 477-479; 1978.

Gray, D. H.; Leiser, A. T. Biotechnical slope protection and erosion control. New York: Van Nostrand Reinhold Co.; 1982.

Gutowski, V. P.; O'Keeffe, M. K.; Dolan, M. T. Sedimentology of Charleston Side-Channel Reservoir. Jorstad, R. B., ed. The general, environmental and economic geology and stratigraphy of East-Central Illinois, 55th triState geological field conference; 1991; Charleston, IL; 1991: 34-41.

Heyer, T. Vegetative measures for streambank stabilization: case studies from Illinois and Missouri. St. Paul, MN: U.S. Dept. of Agriculture, For. Serv., Northeastern Area, State and Private Forestry; 1991; A 13.2: v52/2.

Kohnke, R. E.; Boller, A. K. Soil bioengineering for streambank protection. J. Soil Water Conserv.: 286-287; 1989.

Krasny, M. E.; Zasada, J. C.; Vogt, K. A. Adventitious rooting of four Salicaceae species in response to a flooding event. Can. J. Bot. 66: 2597 -2598 i 1988.

Lamb, G. N. 1915. Willows: their growth, use, and importance. Washington, D.C.: U.S. Dept. of Agriculture, For. Serv.; 1915; 52 p. Bulletin no. 316. 66

Mahmood, K. Reservoir sedimentation: impact, extent, and mitigation. Washington D.C: World Bank; 1987; 118 p. World Bank technical paper no. 71.

McCluskey, D. C. Willow planting for riparian habitat improvement. Denver, CO: U.S. Dept. of Interior; 1983. Technical note 363.

McComas, S. Shoreline protection. N. Amer. Lake Manage. Soc. Lake and reservoir management, vol. II - proceedings of the fifth annual conference and international symposium on lake and watershed management; 1985 November 13-16. Lake Geneva, WI. N. Amer. Lake Manage. Soc.; 1985.

Michniewicz, M.; Kriesel, K. Dynamics of gibberellin-like substances in the development of buds, newly formed shoots and adventitious roots of willow cuttings (Sali:c viminalis L.). Acta Soc. Bot. Pol. 41 (2): 301-310; 1972.

North American Green. Erosional control fabric (SClSO). Evansville, IN.

Northwest Analytical Inc. NWA Statpak (ver.4.11). Portland, OR. 1990.

Platts, W. S. Methods for evaluating riparian habitats with applications to management. Ogden, UT: U.S. Dept. of Agriculture, For. Serv; 1987. General technical report INT-221.

Schiechtl, H. Bioengineering for land reclamation and conservation. Edmonton, Alberta: Univ. Alberta Press; 1980.

Sefton, D. F. Assessment and classification of Illinois lakes: vol. I. 208 water quality management planning program staff report. Springfield, IL: Ill. Environ. Prot. Agency; 1978.

Sommerville, A. H. C. Willows in the environment. Proc. Roy. Soc. Edinburgh 98B: 215-224; 1992.

Stott, K. G. Willows in the service of man. Proc. Roy. Soc. Edinburgh 98B: 169-182; 1992.

Stout, G. E. Introduction. Water Res. Center, Ill. Inst. of Nat. Res. Proceeding of a round table on reclaiming and managing lakes in Illinois; 1980 October 10-11; Champaign, IL. Chicago, IL: Ill. Inst. of Nat. Res.; 1981: vii-xi. Document no. 81/06.

U. S. Dept. of Agriculture, Soil Conserv. Serv. Preliminary investigation report: Charleston Side-Channel Reservoir watershed, Coles County, Illinois. Champaign, IL: U.S. Dept. of Agriculture; 1990a. 67

U. S. Dept. of Agriculture, Soil Conserv. Serv. Use of dormant woody plantings for streambank and shoreline protection. Champaign, IL: U.S. Dept. of Agriculture; 1990b; 11 p. Woodland technical note-IL-16.

White, W. P. Alternate watershed management techniques: a visit to the cost-effective past. Illinois Lake Manage. Association. Lake Waves 7(2): 6-7; 1991. 68

APPENDIX A

Table 9. Raw Data of Willow Survival

#planted #survived #survived # planted #survived #survived row Feb-92 May-92 Oct-92 Feb-92 May-92 Oct-92 Section lw Section lmw 1 13 12 13 13 13 13 2 12 12 12 12 12 12 3 13 13 13 13 12 12 4 12 12 11 12 10 9 5 13 13 11 11 9 8 6 13 8 6 6 5 1 7 14 12 12 8 5 4 4 9 9 9 8

Section 2w Section 2mw 1 14 11 5 13 13 3 2 13 13 9 13 13 11 3 13 11 4 13 13 12 4 13 8 6 13 13 8

Section 3w Section 3mw 1 13 13 4 13 13 11 2 12 12 12 12 12 12 3 13 13 13 13 12 12 4 12 12 12 12 12 12

Section 4w Section 4mw 1 13 10 9 13 8 10 2 12 12 11 12 12 11 3 13 13 13 13 13 13 4 12 12 11 12 12 11

w mw #planted #survived #planted #survived site Feb-92 May-93 Feb-92 May-93 1 105 20 67 12 2 53 2 52 0 3 50 33 50 42 4 50 9 50 23 Table 10. Raw Data of Rebar Erosional Measurements in Centimeters - May 1993

Rebar tw le tmw tm Level 0 4 8 12 16 20 24 28 32 36 0 4 8 12 16 20 24 28 32 36 0.9m 34 22 10 14 0 14 -6 2 10 12 0 0 b 27 14 15 10 21 26

2w 2c 2mw 2m 0 6 12 17 23 29 34 38 0 4 8 12 16 21 25 29 34 40 1.8 m 4 -8 8 1 15 4 7 23 b b b b b 2 0.9m 3 -17 6 28 8 6 6 4 b b b b b 16 2 5 7 4 O.Om 9 15 28 20 23 16 7 35 b b b b 10 21 43 33 31 23

3c 3w 3m 3mw 0 4 8 12 16 20 24 28 32 36 40 0 4 8 12 16 20 24 28 32 36 40 O.Om 18 16 20 17 12 8 6 5 -2 1 0 0 3 0 0 0 0 0 0 0 0 0

4mw 4m 4w 4c 0 4 8 12 16 20 24 28 32 36 40 0 4 8 12 16 20 24 28 32 36 40 0.9m 4 3 6 9 9 0 19 12 19 56 30 57 49 29 25 4 47 29 25 27 O.Om 10 7 18 13 25 23 18 16 12 16 14 13 21 12 19 23 19 12 23 17 25 17

O'I °'°