VEGETATED BUFFER STRIPS A vegetated buffer strip is defined as an area of undisturbed vegetation abutting a pond, lake or wetland that is not mowed, cut or fertilized. It is left undisturbed to prevent sediment, nutrients and pesticides from entering a waterbody, promote groundwater infiltration, and provide wildlife habitat. A buffer strip generally is located adjacent to and parallel with the edge of the waterbody you are trying to protect. It can vary in width extending upland from the waterbody, but generally should be an average of 20 feet wide to be truly effective. A vegetated buffer strip helps protect the water quality of an adjacent waterbody by using the deep network of roots that native grasses and wildflowers - and even trees and shrubs - provide. Unlike the relatively shallow roots of turf grass such as Kentucky bluegrass, this network of deep roots allows the native plants to take up nutrients, direct surface runoff underground, and prevent erosion of the soil. The taller native plants also provide cover and a food source for various forms of wildlife. Root structure of turf grass versus native species There are a variety of plants that can be planted in a vegetated buffer to make it look aesthetically pleasing - much like a garden. These include a wide variety of grasses such as big bluestem, blue grama, Indian grass, Kalm's brome, and switchgrass. Wildflower species may include golden alexander, culver's root, blue flag iris, marsh milkweed, butterflyweed and blue lobelia. River birch, black ash, American hazel, and black willow are common native trees found near waterbodies, as wells as shrubs such as red-osier dogwood, pussy willow, black cherry, and viburnam. It is important that a proper bed be prepared before planting native plants, and there will be some maintenance required for the first few years until the plants have become established. As with the planting of most perennial gardens, the old adage "first year they sleep, second year they creep, and third year Newly planted buffer strip near Earley Lake (adjacent to path). they leap" is also true for native plants. The first few years they will put a lot of energy into underground root growth. When they have a sufficient root structure, they are then able to put more energy into above-ground growth and flowering. Until this time, buffer strips are susceptible to invasion by weeds and other undesirable plants. It will be necessary to control them for the first few years. However, your efforts will pay off when your buffer strip becomes filled with native vegetation providing a variety of colors and textures.
INVASIVE SPECIES CONTROL There are numerous species of vegetation that tend to invade areas in and around lakes, ponds and wetlands. These species are generally non-native, meaning they do not normally Purple loosestrife grow in the region, or even in the United States. Often they are plants that were brought over from Europe as ornamental species and later escaped into our native habitats. Many non-native plant species are considered invasive because they prevent other native species from growing. For instance, purple loosestrife is a common example of a European plant that was introduced into the US, escaped from gardens, and can now be found growing in many of our wetland habitats. This species is considered invasive because it reproduces so abundantly that it can literally take over a wetland and exclude all other plant species. Instead of having a patchwork of habitat types that result from various species of plants, there is a distinct lack of vegetative diversity. Also, purple loosestrife is a somewhat poor food source for birds and other wildlife. Reed canary grass Examples of other non-native, invasive species that are commonly found in or near our lakes, ponds and wetlands include: Reed canary grass Crown vetch Narrow-leaved cattail Queen Anne's lace Common buckthorn Leafy spurge Tartarian honeysuckle Birdsfoot trefoil Smooth brome White sweet clover Silver banner grass Yellow sweet clover Crown vetch Typically, it is best to control invasive species before they have a chance to really establish themselves. If there are few plants scattered here and there, you should remove them by hand so you limit the disturbance to native plants. However, in many urban areas where invasive species are abundant and there has already been lots of disturbance from development, it is often necessary to completely remove almost all of the vegetation and literally start over. Narrow-leaved cattail Usually mowing, spraying with an herbicide, or even burning are necessary, followed by re-establishment of native species through seeding or through the planting of seedlings. Designing a plan for controlling invasive plant species is very site-specific. You should conduct a thorough assessment of the types of vegetation you want to control, and make a detailed plan as to how you intend to control them. If your plan is not followed through, you may find that you have more invasive, non-native species than when you started. Also keep in mind that removal or alteration of some types of vegetation may require a permit from the Department of Natural Resources. Common buckthorn
STORMWATER MANAGEMENT PRACTICES Stormwater runoff from rooftops, driveways, sidewalks and roads is one of our biggest contributors to poor water quality. As precipitation flows over the ground it accumulates sediment, chemicals and debris which are then deposited into low lying areas - usually lakes, ponds and wetlands - or else into our storm sewer system, which also flows directly into our lakes, ponds and wetlands. One of the keys to improving water quality is to reduce and/or treat the runoff that is polluting the water. Although often associated with large-scale development projects, there are a wide variety of relatively simple techniques that can be used around your home or neighborhood to help control runoff. These include - but are not limited to - rain gardens, infiltration trenches, rain barrels, underground cisterns, dry wells, and vegetated swales Depending on site-specific conditions (i.e. soil types, slope of the land, the amount of paved surfaces), each of these techniques can be used to either reduce the quantity and/or help improve the quality of stormwater runoff before it reaches a waterbody. For instance, rain barrels can be used to collect roof runoff and store it. Less runoff means a lower potential for pollutants to get into a waterbody, and the rain barrel stores a nice supply of water to be used in the garden. Spruce Creek RainSaver rain barrel Vegetated swales and rain gardens ('biofiltration techniques') use a plant's natural ability to absorb water and nutrients, thereby reducing runoff quantity and improving runoff quality. Swales are defined as drainage areas - such as between two homes - that are graded at an angle to promote drainage of stormwater into low-lying areas, or into underground sewer systems. If the swales are vegetated with native, deep-rooted plant species the quantity of the runoff can be reduced and the quality greatly improved. Similarly, vegetated garden areas located adjacent to downspouts or elsewhere around a home can reduce runoff and filter pollutants from rooftops, driveways, or other impervious surfaces. Vegetated swale to treat stormwater runoff Another method of reducing runoff is through the use of infiltration trenches that are designed to actually collect runoff and quickly absorb it into the ground. Typically, infiltration trenches consist of sand, crushed rock, or some other porous material that will facilitate the movement of water into the ground. Underground cisterns and dry wells are other methods of actually collecting and storing rainwater below ground, instead of letting it run into low-lying areas or storm sewers. They can be placed underneath downspouts or at other locations where water may collect. Choosing the right stormwater management practice for your site depends upon site-specific conditions as well as what you are trying to accomplish. You must determine if you want to control the amount of the runoff and/or if you are attempting to improve the quality of the runoff entering your lake, pond or wetland. You must also consider if your project could negatively impact surrounding areas (you don't want to flood your neighbor's basement). Then, look at the various options you have to see which one would work for you. Consider the amount of time, money and other resources each would take for installation as well as future maintenance.
AQUATIC VEGETATION ESTABLISHMENT One of the most important areas of a waterbody such as a lake or pond is the shallow water fringe area beginning at the water's edge and extending into the water itself. Shallow water provides a unique habitat for aquatic vegetation specially adapted for growing in the water. Aquatic vegetation provides shelter and food for fish, insects, amphibians and birds. 'Lakescaping for Wildlife and Water Quality' It also helps improve water quality and clarity by absorbing nutrients, preventing shoreline erosion, and preventing the resuspension of solids from wave action. In many developed areas, we tend to remove much of the aquatic vegetation so that we can use the water for swimming or boating. Unfortunately, we are also removing an extremely important type of habitat, which can ultimately affect the entire waterbody. Narrow-leaved arrowhead Collectively known as 'aquatic vegetation', the plants growing in shallow water can be classified into three major groups: emergent, floating-leaved, and submergent. Each group has a unique structure and represents a distinctive type of habitat. Emergents are defined as plants that are rooted in the bottom of a waterbody, however most of the leaves and flowers grow above the water. Common examples of emergent plants include cattails, narrowleaved arrowhead, and bulrush. Floating-leaved species are plants that are often rooted to the bottom, but their leaves and usually flowers float on the surface of or extend just above the waterline. Familiar species include water lilies, duckweed, and yellow lotus. Submergent plants typically grow in deeper areas, and have most if not all of their plant parts underwater (submerged), including roots, stems, leaves, and sometimes flowers. Typical species are pondweeds, wild celery, and coontail. Because of the benefits that native aquatic vegetation can provide to your lake or pond, it is often advantageous to promote the growth of these plants, especially in areas where the vegetation has been removed. Seedlings of various species of aquatic vegetation can be planted similar Bladderwort to most upland plants, however there are a few items to take into consideration. The types and distribution of aquatic vegetation can vary depending on the slope of a shoreline as well as the bottom substrate. A shoreline that quickly drops off into deep water is going to have a fairly small zone of aquatic vegetation, whereas a shallow shoreline can have an abundance of different types of species extending over a larger area. The bottom substrate, whether it be sandy or mucky, can also influence the type of vegetation you may plant. For instance, a sandy bottom is going to favor wild celery and bulrushes, whereas water lilies prefer a mucky bottom to grow in. Also, until the root systems of the deeper water plants become established, it may be necessary to protect them from waves by using temporary wave breaks. It is important to devise a planting plan based on your site before trying to establish aquatic vegetation.
BIOENGINEERING FOR EROSION CONTROL AND SHORELINE STABILIZATION The impact of waves and ice on a shoreline can be significant, causing severe erosion of the shoreline itself. This also allows for a considerable amount of sediment to enter a lake or pond. If the natural vegetation along a shoreline is removed, this only compounds the problem. Sediment that enters a waterbody degrades water quality by introducing nutrients as well as reducing the clarity of the water, preventing sunlight from reaching aquatic vegetation. This can in turn affect the entire ecosystem. Severe shoreline erosion Mechanical shoreline stabilization methods are often used to reduce or prevent shoreline erosion. Rock rip-rap along a shoreline Some common mechanical methods include rock rip-rap or retaining walls. However, these methods can be extremely expensive, often look sterile, prevent the growth of native vegetation, and provide very little habitat for fish and wildlife. In contrast, bioengineering methods using biological resources such as native vegetation, natural fiber blankets or even live wood stakes are less costly, more aesthetically pleasing, and provide wildlife habitat at the same time. Almost all bioengineering methods make use of the deep root structure of native vegetation to hold soil in place as well as absorb some of the impact of waves and ice. Natural wood or Natural fiber blanket held in place by live willow stakes coconut fiber and wattles can be used to protect the soil or provide a wave break until plants become well established. Live wood stakes of willow or dogwood can also be planted. The type of bioengineering that should be used on your site depends upon the severity of erosion as well as the steepness of your shoreline. You should also Live wood stakes consider whether you want to establish vegetation below the waterline or above. If you are interested in planting aquatic vegetation, you need to consider how wave action will affect your plantings, and you may need to provide wave breaks. If planting above the waterline, you should consider whether you want Natural wave breaks for newly planted aquatic plants to use shrubs that could potentially block your view of the water, or use low-growing grasses and wildflowers. It is important to thoroughly research the various bioengineering methods before you devise a shoreline stabilization plan, and to consider all of the time, materials and other resources that will be required before you begin your project. Also, keep in mind that some methods such as planting aquatic vegetation may require a MN DNR permit, which is easy to obtain.
HOW TO GET STARTED: Before beginning a water resources enhancement project, it is important to think about what your goals are. Are you interested in reducing stormwater quantity? Improving stormwater quality? Controlling invasive species? Creating wildlife habitat? Or, do you simply want to enhance the aesthetic value of your pond or wetland? The next step is to devise an appropriate plan to reach your goal. A plan should be thoroughly researched and carefully thought through, taking into consideration all of the resources, tools and maintenance needed for your particular project. There are various publications as well as internet sites available to help you gather information about your project, many of which you can find at your local bookstore or library. Below is a list of references that you might find helpful: Topic Key: B=Buffers, I=Invasive Species Control, SMP=Stormwater Management Practices, AV=Aquatic Vegetation Establishment, BE=Bioengineering, O=Other Water Quality Best Management Practices Publications A Guide to Aquatic Plants - Identification and Management. D. F. Fink. Minnesota Department of Natural Resources, Ecological Services Section, St. Paul. 1997. (I, AV) Aquascaping, a Guide to Lakeshore Landscaping. C. J. Dindorf. Henneping Conservation District, Minnetonka, MN. 1993. (B, AV, BE, O) Lakescaping for Wildlife and Water Quality. C. L. Henderson et al. Nongame Wildlife Program - Section of Wildlife, Minnesota Department of Natural Resources. 1998. (B, I, SMP, AV, BE) Low-Impact Development Design Strategies - An Integrated Design Approach. Prince George's County Department of Environmental Resources. 2000. (SMP) Native Plants for Northern Gardens. L. C. Snyder. Andersen Horticultural Library, University of Minnesota. 1991. (B, I) Natural Landscaping: Designing with Native Plant Communities. J. Diekelmann and R. Schuster. McGraw-Hill Book Company, New York. 1982. (B, I, BE, O) Wetland Plants and Plant Communities of Minnesota and Wisconsin. S. D. Eggers and D. M. Reed, US Army Corps of Engineers, St. Paul District. 1997. (AV) Web Pages American Society of Civil Engineers: www.asce.org/peta/tech/nsbd01.html (SMP) Aquatic Plant Management Society: www.apms.org (I, AV) Bioengineering Group, The: www.bioengineering.com (BE) Low-Impact Development Center: www.lowimpactdevelopment.org (SMP) Minnesota Department of Natural Resources: www.dnr.state.mn.us/waters/ (B, I, SMP, AV, BE, O) University of Minnesota Extension Service: www.extension.umn.edu (B, I, AV, BE, O) Wetland Plants and Plant Communities of Minnesota and Wisconsin: www.npwrc.usgs.gov/resource/1998/mnplant/mnplant.htm ( AV)