Managing Manure: The Role of Riparian Buffers

Fact Sheet Equine Facilities Manure Management Practices June 2003

Equestrians have become aware of the potential environmental impacts that may be caused by their horses and are actively seeking solutions to minimize these problems. A typical 1,000 pound horse may produce 0.75 cubic feet per day of solid waste plus urine, therefore appropriate manure management practices must be implemented at equestrian facilities in order to control runoff containing wastes and thereby protect in nearby . * A number of management practices to store, compost and recycle horse manure to help reduce its environmental impact have been developed and are discussed in other fact sheets and conservation practice manuals for horses (see references at the end of this fact sheet). Riparian Buffers- strips of dense, vegetative cover which include grasses, soft stemmed plants (forbs), shrubs and growing in streamside areas- are one of the most effective tools to help assure clean runoff from horse facilities. Buffers can be considered a last line of defense against the natural downslope flow of runoff down streambanks before that runoff reaches the creek. As with all horse keeping practices, buffers should be integrated with other proven pollution control and management practices and incorporated into a facility’s conservation plan to maximize their effectiveness in protecting overall water quality. Contact your local RCD office for conservation planning assistance.¤

Types of Buffers hile there are many types parian Buffers, because of their associated root systems. W of buffers used in conser- multiple values to humans and and larger streams with year vation practices, their functions wildlife. round flows may support a full are much the same: to improve sized on the banks and and protect ground and surface floodplain. Smaller perennial water quality, reduce , and creeks with lower flows may have provide protection and cover for limited growth which closely wildlife and aquatic life. Filter strips, swales, grass waterways, Inside Contents……. and shelterbelts (rows of trees serving as windbreaks) or hedge- Types of Buffers.………………1 rows (plantings along fence lines to shelter wildlife), are all exam- Streams and Water ples of conservation buffers that may be applied to specific site Quality……….…………………2 conditions. Buffers slow water Proper drainage & buffer Creation and runoff, catch and en- alongside pasture. hance water infiltration in the Improvement……..….…….. 3-4 buffer area itself. Buffers can A Riparian Buffer is an area of trap particles of soil and organic permanent located ad- Maintenance material, utilize the nutrients jacent to a or creek, that is Tips……………..……………….4 from fertilizers and manure, ab- managed to maintain the integ- sorb runoff into the soil to break rity of the waterway, to reduce Stables and Horse down , pathogens, and pollution, and to provide food, Ranches…….…………………...5 other constituents of runoff, , and thermal protection thereby minimizing the chances of for fish and wildlife. Riparian References Cited…...………….5 these potential reach- buffers often act to provide stream ing creeks. One of the most im- stabilization because of portant types of buffers are Ri- their extensive plant cover and

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hugs the bottom and lower sides Area. Riparian areas are typi- creekwater. Some plants and of the creek channel. Flow and cally rich in wildlife due to the trees are dependent on year- flood conditions can vary complex, layered habitat which, round water in the root zone widely, and it is wise to be fa- and grow close to the banks of miliar with current and past the creek; others prefer positions flow events in your stream when higher on the bank or flood- establishing a riparian buffer plain. Therefore soil moisture zone is being considered. and shade conditions can vary Depending upon what the land greatly in the streamside area. can naturally support, riparian This is important to understand cover may consist of a dense when choosing plants if new mix of grasses, grass-like plantings are planned for the plants, forbs (soft-stemmed riparian buffer.¤ plants), shrubs such as berries, vines such as wild grape, and/ or trees such as willows, red Grassed drainage area. alders, sycamores, maples, and other native plants typically if fully developed, includes a found along streams in the Bay leafy forest canopy to shade shrubs, groundcovers below and How Riparian Buffers Work to Enhance the Streamside Area and Protect Water Quality. Sediment and pollution utilization and soil storage fol- near-surface groundwater will filter lowed by breakdown, minimizes reach the waterway at a much the amount of sediment and slower rate over a longer period pollutants that could enter the of time than if it had directly iparian vegetation slows waterway. flowed into the waterway. Wa- R down runoff, allows wa- ter infiltration helps control ter to infiltrate, and causes flooding and maintains water the sediment (particles of soil Streambank and bed flow even during dry periods. and organic material) and pol- lutants to settle out of the water stabilizer and deposit in the buffer. Grass Water holding capacity and stems of forbs and shrubs lant roots hold bank soil slow the rate of flow of water P together and plant stems down streambanks (through the protect banks by deflecting the iparian Buffers benefit buffer) thereby increasing infil- cutting action of storm runoff. R aquatic habitat by im- tration of water into the soil. The vegetation helps stabilize proving the quality of nearby Soil and pollutants banks and reduces erosion. Ri- waters though shading, filter- are then trapped, modified by parian Buffers also reduce the ing, and moderating stream soil bacteria, or used by the amount of scouring because the flow. Shade provided by the various plant root systems for vegetation absorbs surface run- plants maintains cooler, more growth. Nutrients from manure off, which slows down water even water temperatures. dissolved in runoff can be taken velocity. Cooler water holds more oxygen up and used by plants that are that helps reduce stress on fish vigorous and actively growing. Water Flow Regulator and other aquatic animals. Other contaminants in runoff Plant debris also contributes to from horse facilities can include ith the vegetation slow- a more complex food web pro- residues (fly sprays W ing down the velocity of viding a food source to mi- and wormers) herbicide resi- the runoff, the Riparian Buffer crobes, insects and other inver- dues, chemicals from soaps and allows water to infiltrate the tebrates benefiting all fish and other horse-care products, and soil and recharge the ground- wildlife. pathogens. The processes of water supply. Another positive particle trapping, infiltration, environmental benefit is that

(Continued on page 3) 2 (Continued from page 2) Wildlife Habitat plants amend the soil, and host Having a Riparian Buffer along innumerable bugs and other soil- your creek adds to the value of dwelling animals. Continuous your land because it improves the he distinctive habitat of- stretches of Riparian Buffer also environment.¤ T fered by riparian buffers serve as safe wildlife travel corri- provides food, water and homes to dors, and if oriented across the a multitude of plant and animal path of prevailing winds, can species, including those rarely serve as a windbreak. The trees found outside this narrow band of and tall shrubs in a buffer can land. The layers of vegetation in a also absorb or collect airborne include a leafy can- dust particles. opy which is home to many , Aesthetic including flycatchers, owls and raptors which are helpful to equestrians in insect and rodent he biological complexity control. Many shrubs provide T and natural beauty result- cover and food; notably seeds and ing from a Riparian Buffer are berries for birds. On the forest visually pleasing. Riparian Buff- Vegetated slope to drainage. floor are flowering annual and ers are especially valuable in pro- perennial plants which support viding a green screen along wa- numerous beneficial insects. Lay- terways, blocking views of nearby ers of decomposing leaves from neighbors, and providing privacy.

How to Create or Improve a Riparian Buffer

any coastal streams gentle slopes and even surfaces and utilization of nutrients, but M flow through narrow result in greater sheet flow of a low benefit for bank stabiliza- valleys where usable land is at water through the buffer, tion and flood protection. Trees a premium. The minimum thereby maximizing benefit. have a high benefit for flood width of a Riparian Buffer will Wider buffer strips have longer and bank stabilization because be dependent upon a number of flow lengths for treating runoff. of their deep and extensive an- factors specific to a property This combined with nearly flat choring root system, but no abil- such as the size of the stream, to very gently sloping stream ity to filter sediments. Always slope of the stream bank along sides and dense ground cover use local native vegetation, and individual reaches, the total vegetation will allow maximum plant at the appropriate time of amount of land available, exist- infiltration. . Greater width the year. Be aware of the ing land uses, and economic may be required for steeper amount of sunlight that is factors. Generally, the wider slopes, because the faster rate of available below the tree canopy the buffer, the greater the envi- runoff flow through the buffer (if present) , as some plants and ronmental benefit. Narrow means les opportunity for parti- most grasses require sunny con- buffers require careful consid- cles to be trapped and water to ditions. Evergreen trees keep eration of slope and selection of be infiltrated. Wider buffers are their leaves year round, so they vegetation to insure effective- needed if sediment loads are may block needed sunlight dur- ness and have reduced wildlife high in runoff flowing into the ing the winter months. How- habitat benefits. buffer. ever, evergreen trees provide good wildlife habitat during Slope and soil conditions must Selection of appropriate plant those months. Plant some of be considered in order to maxi- materials including the right each if possible, such as a mix mize water infiltration in the mix and percentage of grasses, of life (evergreen) and decidu- soil. may be car- forbs, shrubs and trees deter- ous oaks. ried downward or infiltrated mines the effectiveness of the When establishing a new buffer, into the soil if the water is flow- buffer and therefore the benefits the choice of plants may also ing slowly in a very thin to be achieved. For example, depend upon the availability of (shallow) layer called ‘sheet grasses have a high benefit for irrigation for the first two to flow’. Generally, buffers with sediment trapping, filtration three years of plant growth. If

3 (Continued from page 3) irrigation is present, plantings not be removed and grading fencing needed to keep horses of trees and shrubs can be done should not be done in stream- and other livestock out of the year round, however late fall is side areas without permission. area. The NRCS and RCD can usually the best time to plant. also explain the value of conser- Without irrigation, grasses and A first step in creating or im- vation plans and federal cost wildflowers can be planted from proving a riparian buffer is to share programs, including en- seed in October, oak acorns can contact your local Resources rolling your buffer in the Con- be planted in chicken wire bas- Conservation District (RCD) to servation Reserve Program.¤ kets to protect them from go- obtain general assistance phers, and willow cuttings can through the Natural Resources be placed into soils that are Conservation Service (NRCS). naturally damp or wet most of Alternatively, you may contact a the year. Check with local na- private, NRCS approved techni- tive plant experts or trained cal assistance provider who can nursery staff for further ideas help answer questions specific about non-irrigated planting to your land and stream bank methods. Horses and livestock situation. They can also help should be fenced out of riparian evaluate the existing riparian areas. Finally, you may also be area to identify needed repairs advised to remove non-native such as eroding streambanks, vegetation from the riparian potential management issues Paddock separated from road by zone. However, native vegeta- and constraints such as stream- vegetated strip. tion in the buffer zone should bank crossings for horses, or Maintenance Tips

o maintain their effective- Grass and forbs in a Riparian Replacing dead or dying trees T ness, Riparian Buffers Buffer can benefit from mowing and shrubs and reseeding bare need to be managed. Regularly during the early years after soil are important maintenance scheduled maintenance should planting. Mowing increases the practices during the first few be implemented right after the vigor of grasses, and encourages years following establishment. buffer has been planted. This new blades of grass and more An annual inspection should be may include weed control, re- stems at ground level – which made to identify areas in need planting trees and shrubs that increases density and hence of replanting/reseeding. Re- did not survive the initial plant- sediment trapping capacity. planting can be done in the ing, reseeding bare areas, prun- Grasses and forbs often grow spring or fall. Trees should be ing, thinning, mulching and slowly above ground during the pruned during late fall, winter, irrigation system monitoring. first year or two after establish- or early spring while the plants Riparian Buffers should be ment because much of their en- are dormant. Thinning should carefully inspected annually or ergy is put into producing a root take place in late spring if tree after major storm events for any system. During this time an- or shrub growth is too dense damage or problems that may nual weeds can grow rapidly. and groundcover plants are be- have occurred. A key concern is Mowing just before annual ing shaded out. This can be making sure that runoff to be weeds produce their seed keeps done systematically by remov- “treated” in the buffer is flowing the seed from maturing and ing every other row of branches through it in a shallow, slow- producing more weeds. If trees or every other tree.¤ moving layer and not in chan- or tall shrubs begin to shade nels or tiny channels called out soil-hugging grasses and “rills” . This can best be seen forbs, the runoff-slowing and during or just after a storm particle-trapping work of the when flow patterns are obvious. groundcover plants will be lim- Repairs should be made as soon ited. as possible to insure proper buffer function.

4 How Can Riparian Buffers Help Horse Stables and Ranches? s part of your overall con- amount of contaminants in run- quality of life. And these quali- Aservation plan, Riparian off, can provide a final point of ties add value to your prop- Buffers will help improve water protection to keep manure, erty.¤ quality through filtering proc- urine, and other chemicals, out esses, provide erosion and sedi- of surface waters. Riparian ment control through appropri- Buffers provide ate vegetation, create suitable by stabilizing banks with vege- habitat for wildlife, and add to tation. This means less land is the value of your property aes- lost or washed downstream and thetics. Both horses and their more land is available for grow- owners will end up with better ing and grazing. Riparian drinking water as surface and buffers also provide beautiful ground water sources are pro- landscapes, which supply pri- tected. Riparian Buffers, used vacy, shade, windbreaks and in concert with other conserva- other environmental qualities tion measures to reduce the that we associate with a good Well vegetated riparian zone keeps creeks healthy. Resources and References

* The volume of manure produced daily has been estimated by various writers and researchers. This figure does not include bedding. The figure used in this fact sheet, .75 cubic foot per day per 1000 lb. Horse, corresponds with that in the Horse Keeping: A Guide to Land Management for Clean Water. The source for the figure is Livestock Waste Facilities Handbook, 1985, Midwest Plan Service- 18, Iowa State University, Ames Iowa.

National Conservation Buffer Council: http://www.buffercouncil.org Natural Resources Conservation Service: http://www.nrcs.usda.gov/feature/buffers/ Riparian Herbaceous Cover, Technical Standard 390 http://efotg.nrcs.usda.gov/treemenuFS.aspx?StateName=California&MenuName=menuCA.zip&MenuType=2

The following Fact Sheets were developed by the Council of Bay Area RCDs and are available from your local RCD office: Land Application of Horse Manure, CBARCD, October, 1999. Equine Manure Storage Fact Sheet Equine Facility Site Assessment Checklist, Available from the San Mateo County RCD Composting Horse Manure, CBARCD, June, 2000 Horse Manure Management, CBARCD, June, 2000 Portable Backyard Garden, CBARCD, March, 1999 • Photographic Monitoring, CBARCD, June, 2000

See “Riparian Buffers” in Horse Keeping: A Guide to Land Management for Clean Water, 2002, manual avail- able from Council of Bay Area RCDs

RCD Websites: 1) Marin RCD and Southern Sonoma RCD - www.sonomamarinrcd.org 2) Alameda RCD - www.baysavers.org 3) San Mateo RCD - www.sanmateorcd.org¤

The “Equine Facilities Assistance Program” is a grant funded project of the Council of Bay Area Resource Conservation Dis- tricts, and the Alameda, Marin, San Mateo and Southern Sonoma RCD’s. The manure management fact sheet series was produced with the assistance of the USDA Natural Resources Conservation Service (NRCS).

Funding for this project has been provided to the Council of Bay Area RCD’s in part by the U.S. Agency (USEPA) pursuant to Assistance Agreement No. C9-989697-00-0 and any amendments thereto which has been awarded to the State Water Resources Control Board (SWRCB) for the implementation of California’s Nonpoint Source Pollution Control Program. The contents of this document do not necessarily reflect the views and policies of the USEPA or the SWRCB, nor does mention of trade names or commercial products constitute en- dorsement or recommendation for use.

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