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SUN-‐B06_Native Meadows & Grasslands -‐ 1

Native Meadows and Grasslands: From Vision to Reality

James Patchett & Larry Weaner Learning Objectives

• Become familiar with how local geology, soils, flora, fauna, hydrology, climate, and cultural factors have shaped North American grassland systems.

• Gain insight into how native meadow/grassland restoration is being used to develop new paradigms in agriculture, ecological restoration, and sustainable community development.

• Learn how to design and specify a native meadow/grassland using seed and live plants. • Understand how to manage and guide native meadows/grasslands at all stages of their evolution. Section I | James Patchett The integration of native grassland systems represents far more than just an alternative landscape treatment. Native grasslands are an important component of an environmentally restorative, economically sensible approach to land development and management for all types of land uses including commercial, corporate, and institutional campuses, parks and open space systems, and residential settings, to name a few. It is also likely that native grassland restoration will play an important role in the success of emerging restorative agricultural practices.

The proper design, installation, and management of native landscapes create a living landscape composed of diverse communities of plant species that can sustain themselves and thrive in the unique ecological habitats found throughout North America. From an aesthetic point of view, native landscapes produce a constantly changing pattern of striking colors and textures throughout the seasons. Although some natives can be utilized in a more traditional horticultural planting as a specimen plant, most species should be designed, installed, and managed within the context of a discrete, living system. Creating the conditions to which species have historically adapted including human relationships such as fire and other stewardship activities is essential for success. In addition to aesthetic richness, native landscape systems offer a variety of environmental and cost savings benefits. Environmental benefits include, but are not limited to, the reduction of surface

water runoff and downstream flooding, reduced soil erosion, the re-‐development of organic topsoil, increased groundwater recharge, enhanced regional air and water quality, restored

University Research Park, Madison WI. Photo: Bruce Woods (top), James Patchett (bottom).


wildlife habitat, and increased bio-‐diversity of both flora and fauna. Long-‐term maintenance cost savings can also be significant. With proper design and installation, along with equally critical ongoing stewardship and management (all 3 phases are equally important for success), established native grassland systems can be maintained without mowing, or the long term use of fertilizers, pesticides, herbicides, or supplemental watering. Not only good for the environment, once established over the first 5 + years, native landscape systems can result in annual long term maintenance cost reductions of as much as 80-‐90%, in comparison to traditional turf grass maintenance costs. It is not uncommon for maintenance cost savings in the range of 40-‐50% to be achieved during the early establishment years. While my colleague Larry Weaner’s presentation will emphasize how to creatively incorporate native grassland and meadow systems of the Eastern US into contemporary landscape design, my presentation will focus on the many benefits associated with the integration of the Tallgrass ecosystems of the Midwest. In order to better grasp the range and magnitude of potential benefits associated with the integration of native grasslands, it is critical to gain an increased understanding of how these systems evolved and functioned historically.

The growth character and adaptations of native prairie species are quite unique. Most of the plant mass of a prairie community is underground in the form of extensive root systems. The richness and fertility of Midwestern soils owe their properties to the morphology and hydrology of the grasslands, where subterranean reduction exceeded oxidation. Prairie lands, with their deep roots and water holding root systems, once stored net amounts of soil organic carbon (SOC) each year in the creation of deep black topsoil. On average, 70-‐90% of a prairie grass’s total mass existed

below ground. The root systems could reach or exceed depths of 10 -‐ 15 feet. A typical tallgrass prairie generally contained 15 to 20 thousand kilograms of root mass/ hectare, which equates to 12 -‐ 18 thousand pounds of root mass/acre. Each year, approximately 1/3 of the root system died-‐off and formed partially decomposed matter that was rich in organic carbon through the process of photosynthesis. Depending on the dryness or wetness of any specific habitat, the average net accumulation rate of SOC throughout much of the region typically ranged from 0.5-‐2 tons/acre/year. In contrast, annual corn and soybean systems contain, on average, 300 to 600 kilograms of root mass/hectare, and result in an annual net loss of soil organic carbon, rather than a net gain.

Historically, the terrestrial ecosystems of North America, particularly in the tallgrass prairie ecosystems of the upper Midwest, were very effective at receiving and absorbing rainfall. Prior to conversion into contemporary urban, suburban, and rural agricultural land uses, prairie ecosystems, with their combination of vegetation cover, fibrous roots systems, and soils with low bulk density and high organic matter content created an environment where very little water ran off the surface of the land. The historical patterns of hydrology throughout the region, and for that matter throughout most of the continent, were prevailingly dominated by groundwater hydrology coupled with contributions from

The root structure and rhizosphere of native grasslands influence infiltration and groundwater hydrology.


direct precipitation. Most natural wetland and aquatic systems including lakes, streams, and rivers were predominantly formed and sustained by constant sources of groundwater discharge, or from surface water systems derived from steady, stable groundwater discharge. Discharge occurred anywhere along the spectrum from higher to lower gradients, depending on the relationship of geology, soils, surface and groundwater gradients, and other factors. Virtually all of our endemic terrestrial and aquatic species, both flora and fauna, are adapted to such stable patterns of infiltration, evaporation, transpiration, groundwater discharge, consistent hydrology, and stable water chemistry. Growing season floods comparable to the frequency and magnitude that we suffer today in late spring and summer would have been extremely rare if not impossible to have occurred. No matter how hard the rain, the prairie was very effective at absorbing the rainfall, and the region’s wetlands, streams, and rivers remained very stable throughout the growing season both in terms of water levels, and water chemistry. Disruption of grassland ecosystems, in most cases through agricultural tillage or mass grading, results in the exposure of these highly organic soils to the atmosphere. Exposure promotes oxidation of accumulated soil organic carbon, which in turn reduces the soil’s tilth and its capacity to absorb rainwater and hold nutrients. The loss of a strong perennial ground cover exaggerates the rate and amount of soil loss and resources as the exposed soil becomes increasingly susceptible to wind and water erosion. After several years of repeated tillage, the extensive root system of prairie disappears altogether and a once highly organic soil becomes primarily mineral in composition. Compaction and loss of root structure and organic matter content from mass grading or repeated tillage alters soil bulk density causing water infiltration rates and capacity to drop dramatically. Introduction of drainage tile acts to accelerate the rate of water loss, oxidation, and depletion of soil nutrients. In turn, ornamental landscapes and agricultural crops need significant additional resources to grow including fertilizers and water. In both urban and rural environments, the impact of fertilizers, herbicides, and pesticides in our soil, and surface and groundwater systems is well documented, but other negative influences associated with annual row crop tillage are far less understood. As the water in the soil is drained away, the reduction/oxidation relationships change dramatically. Whereas once the prairies held their water, and carbon was fixed beneath the surface in net amounts, annual row crop tillage now causes carbon to be oxidized more rapidly than it is fixed, a situation exacerbated by the constant drain of water through the tile systems and into the ditches. Consequently, during each growing season, carbon dioxide that was fixed millennia ago is now released into the atmosphere in amounts greater than it is taken up, which potentially contributes to the problem known as global warning. This net release of soil organic carbon (SOC) is not a minor concern. Recent studies on the amounts of carbon stored in the Conservation Reserve Program (CRP), in which deep-‐rooted native grasses are planted in some of the less productive or more erodible soils, have shown that ten years of SOC storage can be oxidized within a single growing season after tilling. In fact, more than 90% of the fixed carbon can be released in the first 15 days following tillage, and that net loss can occur within 30 days. One pound of SOC, once oxidized, generates 3.4 pounds of carbon dioxide emissions. If the net SOC accumulation rate averaged 1 ton/acre/year for a ten-‐year cycle of CRP planted in native grassland, the CO2 emissions would equate to approximately 18,000 x 3.4 or 61,200 pounds of CO2 emissions/acre over a 15-‐30 day period. For comparison purposes, a car or lawn mower emits approximately 16 pounds of carbon dioxide, carbon monoxide, etc. for every gallon of gasoline burned. This is of course fossil carbon, the effects of which are of concern in our contemporary atmosphere. The ecological impacts associated with this type of wholesale landscape conversion are obviously substantial.


Soil and water loss, coupled with air and water pollution are not the only concerns. As described by my CDF colleague, Dr. Gerould Wilhelm, when the rhizosphere, which includes the deep root systems of the native bunch grasses is destroyed, a chain reaction of negative impacts is generated: In contrast to traditional stormwater engineering practices designed to direct water away from where it falls, restorative approaches to site and regional water resource management strive to treat water as a resource, not a waste product. Such measures revolve around the restoration of stable groundwater hydrology on a site and regional watershed basis through the incorporation of cost effective measures that effectively cleanse, diffuse, and absorb water where it falls, thus restoring the historical patterns of groundwater dominated hydrology and water quality. This should be the fundamental design and engineering goal of every type and scale of development project, regardless of whether it is situated in an urban, suburban, or rural environment. The integration of native grassland systems in contemporary environments is a fundamental component of this restorative process. The emergence of green infrastructure systems has demonstrated that many practical, cost effective design and development innovations directed at the restoration of hydrological stability and enhanced water quality in urban, suburban, and rural environments can make a positive impact. Landscape architects have been instrumental in pioneering the design and development of innovative green infrastructure techniques that bring water’s positive properties to bear, often replicating historical patterns of hydrology. Green technologies such as vegetated green roofs, porous pavement systems, bio-‐swales, rain gardens and other bio-‐retention measures, rainfall harvesting and re-‐use measures such as storage cisterns, and the incorporation of deep-‐rooted, highly absorbent native landscape systems are but a few of the multi-‐beneficial, cost effective landscape scale water resource management strategies that may be applied. Such measures are important elements for groundwater recharge, flood reduction, site and regional water quality enhancement, and the restoration of terrestrial and aquatic ecosystem viability. In urban and suburban environments, the proper design and stewardship of native prairie landscapes can form the backbone of a thoroughly integrated green infrastructure system when combined with other green infrastructure measures in the built environment. With a hierarchy of integrated green infrastructure measures in place, a fundamental goal should be to never expose these native landscape systems to direct piped stormwater discharge. These landscapes should represent the last line of defense in a comprehensive on-‐site water resource management strategy.


While an understanding and appreciation of how to incorporate native landscape systems into contemporary urban and suburban environments has grown substantially over the past quarter of a century, the potential for the integration of restored native grasslands as a fundamental component of restorative agriculture may be even more substantial. Restorative agriculture practices are directed at the creation of watershed based solutions that showcase highly integrated and diversified farming operations designed to create value-‐added products from species that simultaneously contribute to ecosystem health and create new revenue streams. A primary focus of this effort will include the incorporation and examination of direct economic and environmental benefits associated with diverse native prairie grassland restoration and seed and bio-‐mass production for alternative energy systems. In addition to energy and seed production, fiber production for a wide variety of annually renewable products such as paper, cardboard, plastic, and textiles, as well as botanicals may be considered. A rotational program of integrated grazing and rest, to ensure that the process restores systems vitality, is also anticipated. The ultimate configuration of uses would be based, in large part, on the physical characteristics of each site, sub-‐watershed, and region. Key design factors would include site and regional topography, soils, geology, and surface and groundwater hydrology.

In a comprehensive watershed-‐scale restorative agricultural approach, the restored native grasslands will be combined with a diverse suite of ecologically restorative agricultural production practices situated throughout the adjoining landscapes, collectively designed to provide greater revenue streams with less risk. The intent is to illustrate realistic, cost effective, environmentally restorative measures that can aid in the dramatic reduction of North America’s reliance on foreign oil imports, and to demonstrate and promote new paradigms in Midwestern agriculture, ecological restoration, and sustainable community development based on energy independence, sound economics, and environmental stewardship. It is anticipated that these measures will create a diverse suite of value-‐added byproducts and revenue streams for reintroduction into the local community and agricultural economy. The lessons learned can be applied throughout the Midwest and well beyond.


Section II: Meadow/Grassland Design, Installation, and Management | Larry Weaner The following materials represent a range of considerations and techniques relevant to meadow/grassland design, installation, and management. While not an exhaustive guide to meadow/grassland creation, what is provided here includes many of the most pertinent aspects. A. Key Site Analysis Considerations

• Light is critical: Full sun (six hours minimum) is required. Insufficient sunlight will favor woody species over herbaceous wildflowers and grasses, causing an increase in maintenance requirements. By undercutting meadow vegetation, lack of light will also favor weed invasion.

• Know your soils: Meadows can thrive on a variety of soil types—sand, loam, clay, etc.—but each requires a different suite of adapted plants. Barring an extreme deficiency, do not amend soils. Leaner, lower pH soils can be advantageous as they are less conducive to weedy growth.

• Grade and topography matter: Determine microhabitats created by grade and topography and modify planting choices to suit. Topography can also affect planting schedule: a sloping site may require a spring seeding as fall planted meadow seed typically remains dormant until spring and is liable to wash away on a slope over the course of a winter.

• Existing vegetation can provide clues: Assess existing vegetation to obtain valuable information regarding what plants will grow well on the site and what specific weedy species are likely to present a problem. If a native meadow species already occurs on the site, include it and its associates in your meadow palette.

B. Design

Assembling a Plant Community

Mimicking the growth of natural grassland and the niches found therein will make for the most stable, resilient, and functional planting. Even a cursory look at a mature prairie or wild meadow will reveal an incredibly dense tapestry with a canopy, numerous middle layers of growth and a creeping understory. This dense interweaving of stems and foliage should be mirrored underground by the root systems of the meadow grasses and wildflowers, with shallow, spreading mats of roots that fill the upper layer of soil complemented by deeper-‐reaching tap and fibrous roots that fill the soil underneath. Such a dense fabric of growth is remarkably weed resistant once established. Temporal niches also need to be filled. There are two time scales to consider with meadows. The first is seasonal. Some plants such as the native meadow grasses grow most actively during the warm weather season, from late spring until early autumn, while other plants make their growth during cool seasons, especially spring. To neglect either group in your planting is to invite an invasion of weeds with a corresponding season of growth. The second time scale is one of years. To keep the weeds at bay, a meadow should include fast-‐growing plants that cover the ground during the first year of growth, biennials and short-‐lived perennials to take over as the first year plants fade, and longer-‐lived perennials to provide long-‐term cover. All of these need to be present to prevent a vulnerable gap in the meadow’s ability to resist weeds.


There is one additional niche to fill in the meadow, one that is neither spatial nor time related. These are plants in the legume family, which fix nitrogen from the air and add it to the soil. This produces a modest increase in fertility. Whereas the high levels of fertility that fertilizers produce pose a threat to meadow plantings, the level of fertilization furnished by legumes is typically perfectly suited to the meadow plants that co-‐evolved with the nitrogen-‐fixing plants. Plant decomposition also affects fertility. Again, if you’re using a plant community model, the fertility levels that result from the decomposition of those plants should be optimal to support that community.

Seed Mix Formulation

a) Determine the square footage of the project area. b) Determine desired seeds per square foot (typically = 150-‐200 seeds per square foot for main mixes,

60-‐80 seeds per square foot for overlay mixes). c) Assign a percentage of the total mix to each species, totaling 100%. Note: grasses should generally

consist of 40-‐100% of the mix. d) Calculate the number of seeds needed to fulfill the assigned percentage for each species: a x b x c =

d (number of seeds needed for each species). Convert the number of seeds to weight for each species.

e) Divide d by the number of seeds per ounce of species. (Seeds per ounce of each species can be obtained in online searches of plant name seeds per ounce or in seed house catalogues.)

If this bit of mathematics seems intimidating, a workaround exists: complete steps A through C (no math required) and submit those figures to a reputable seed house, which can then take care of steps D and E. Just be sure to let the seed company know that the submitted percentages refer to seed counts, not weight. In addition to perennial grasses and wildflowers (forbs), you’ll also want to include a nurse or cover crop in your seed mix. Cover crops typically consist of fast germinating, clump-‐forming annual grass such as oats or intermediate rye. By providing quick coverage of the site, the nurse crop helps to reduce weed invasion and soil erosion during the first season after planting. This is very important for the meadow is most vulnerable at this time because the longer lived perennials and grasses are not yet well enough established to stabilize the soil. These annual grasses are commonly used for this purpose in the construction trades. Possible cover crops are listed in the sample seed mix on the following page. Incorporate your nurse crop into the seed mix, and you have a custom designed seed blend that contains species names and quantities for each (expressed in weight), which you can now submit to a seed house or houses.

-‐ A sample seed mix appears on the following page. -‐


Sample Seed Mix

This sample seed mix for an upland meadow site in the northeast may appear to include a lot of species but keep in mind that a certain percentage are early successional and will drop out as longer-‐lived growth takes over. The early-‐successional species should reappear in the event of disturbance.

Nurse crops are listed as options based upon the seeding time. Once a seeding time has been determined, the relevant nurse crop can be specified.

Using Live Plants

In some instances, using container-‐grown—i.e., live plants—in addition to seed may be desired. This has the advantage of faster establishment, with the meadow maturing in a year or two rather than the multiyear time frame that starting from seed typically requires. Some meadow species can take five to ten years to reach flowering size and these would be good candidates to plant live. All the wild indigos (Baptisia spp.), Culver’s root (Veronicastrum virginicum) and wild quinine (Parthenium integrifolium) fall into this category. And some plants don’t come at all from seed when sown directly into the landscape,

DATE: March 1, 2014

Seed Mix SpecificationsProject name/location: MA meadow Results (excluding cover crop)

Mix: M1 - Main Mesic 19 lbs. of seed/acreArea in acres = 1.1 20 Total lbs. this mixArea in sq ft = 46,030 21 Total spp.

Total seeds per sq ft (150-200 suggested) = 150 5 Number of graminoides% graminoids (suggested range: 40-70%) = 60% 16 Number of forbs

Botanical Name Common Name% of Mix Qty

Seeding Notes Substitutions/Comments

Ht (ft/in)

Season/Color

Grasses, Sedges and RushesAgrostis hymalis Hair Grass 15.00% 1.38 oz 1-2' coolCarex vulpinoidea Fox Sedge 22.00% 9.11 oz 1-3' coolElymus villosus Silky Wild Rye 3.00% 22.60 oz 1-3' coolSchizachyrium scoparium Little Bluestem 44.00% 121.52 oz 2-3' warmTridens flavus Purpletop 16.00% 23.42 oz 2-5' warm

100%ForbsAsclepias tuberosa Butterfly Weed 1.00% 6.42 oz 1-3' SummerAster laevis (Symphiotrichum) Smooth Aster 10.00% 5.02 oz 2-5' FallChamaecrista fasciculata (Cassia) Partridge Pea 3.00% 30.69 oz 1-6' SummerCoreopsis lanceolata Tickseed 10.00% 13.81 oz 2-3' SpringEchinacea purpurea Purple Coneflower 9.00% 37.66 oz 3-5' SummerEchinacea tennesseensis Tennessee Coneflower 2.00% 9.21 oz 2' SummerEryngium yuccifolium Rattlesnake Master 4.00% 14.73 oz 3-5' SummerLespedeza capitata Round-headed Bush Clover 1.00% 3.45 oz 2-4' SummerMondarda punctata Horsemint 10.00% 3.07 oz 1-2' SummerPenstemon digitalis White Beardtongue 15.00% 3.19 oz 2-4' SpringPycnanthemum tenuifolium Slender Mountain Mint 7.00% 0.51 oz 2-3' SummerRudbeckia hirta Black Eyed Susan 10.00% 3.00 oz 1-3' SummerSolidago nemoralis Gray Goldenrod 10.00% 0.92 oz 1-3' FallSolidago rigida (Oligoneuron) Stiff Goldenrod 3.00% 2.02 oz 1-5' FallTradescantia ohioensis Ohio Spiderwort 2.00% 6.90 oz 2-4' SpringZizia aptera Heart-leaf Golden Alexander 3.00% 6.90 oz 1-2' Spring

100%Nurse CropAvena sativa Oats 20.92 lb Spring seedingEchinochloa crusgalli Barnyard Grass 1.05 lb Wetland seedingHordeum vulgare Barley 31.38 lb Summer seedingLolium multiflorum Annual Ryegrass 5.23 lb Summer/fall seedingSecale cereale Rye 31.38 lb Summer/fall seedingTriticum Winter Wheat 10.46 lb Fall seeding

Notes:1. USE THE FOLLOWING ECOTYPES IF AVAILABLE:

NORTH EASTCT, MA, NY, NJ


such as Canada anemone (Anemone canadensis) and milkvetch (Astragalus spp.). If you want these plants in your meadow, you have no choice but to install them as live specimens. Using live plants also allows for more precise arrangement of species. C. Installation

Site preparation is of the utmost importance in achieving a successful meadow. It begins with elimination of existing growth. The most common elimination methods are repeated applications of short-‐lived herbicide sprays, repeated tilling or a combination of the two. Tilling will bring to the surface dormant weed seeds, which must be allowed to germinate and then shallowly cultivated or sprayed with herbicide before planting. This can be avoided with a no-‐till seeding if a shallow seedbed can be worked up among the dead plant material. Tarping or smothering existing growth can also be done, but this can be cost/resource prohibitive over a large scale. Depending on the scale of the site and presence of obstacles, seeding occurs with walk-‐behind equipment or tractor-‐pulled equipment, such as a no-‐trill drill seeder (e.g., Truax brand) able to accommodate the sizes and textures of native grass and forb seeds. D. Post-‐Planting Management

Understanding ecological succession is key to meadow maintenance. Succession is the process by which a disturbed area progresses naturally from herbaceous meadow (first annuals then perennials) to woody shrubs and pioneer trees and finally to a mature forest. In dry portions of the country, various forms of prairie are the mature stage of the process. By establishing a permanent meadow where woods naturally predominate, however, we are arresting the process of ecological development at the herbaceous perennial stage. It also important to understand that while a meadow or grassland, once established, will require substantially less maintenance than mowed lawn, the first one to two years will require guidance in order to achieve success. A maintenance plan should be in place before starting to insure that this crucial portion of the project is not neglected. During the establishment period, it will be necessary to carry out a routine weed control program to ensure successful establishment of the meadow. The most appropriate methods are determined by the size of the project, maintenance budget, method of installation, and the appearance of weed species. Year 1 Management

As the process of ecological succession would suggest, the first year will bring a rapid cover of the seeded cover crop as well as annual weeds, while the perennial wildflowers and grasses are slowly developing underneath. This is to be expected, and if managed properly, is not a problem. By mowing the first year meadow during the growing season to a height of 4-‐6" whenever growth reaches 10-‐14” (see graphic on subsequent page), you not only prevent annual weeds from seeding, but also insure that the young perennial plants growing below your mow height receive enough light for strong establishment. These perennials will emerge the following year far stronger than if they had been buried

Seeding with a no-‐till drill seeder. Note the closely mown thatch rather than tilled soil.


under four feet of annual foliage the first year. This is why the inclusion of annual wildflowers in your seed mix can be detrimental to the long-‐term health of the planting. Annual wildflowers are included for their ability to bloom the first year. In order for this to occur, you are prohibited from mowing, which allows annual weeds to go unchecked and deprives the emerging perennials of the light needed for optimal growth. When mowing, use equipment that chops dead top growth (flail or rotary style). Sickle bar type mowers, which cut at the base and drop plant material intact, should not be used, as meadow seedlings can be inhibited. In locations inaccessible to a mower (wet areas, steep slopes, around trees, etc.), string trim vegetation to 4-‐6”. Do not remove chopped plant refuse, as it returns organic matter and nutrients to the soil. Any thick accumulations of cut material that remain to the point where soil cannot be observed through the cut material should be dispersed evenly over the site or removed. Year 2 Management

During the second year, the faster growing perennials (Black Eyed Susan: Rudbeckia hirta, Coneflower: Echinacea spp., Bee Balm: Monarda spp.) will begin to provide color, and the entire planting should be well enough established to allow a decrease in weed control, although you still need to monitor the planting for those weeds that can cause problems for the meadow. If necessary, control can be obtained through spot herbicide application, manual weeding, or an additional mowing immediately following the most active growth period of the problem weed. Year 3+ Management

By the third year, native meadow plants should be fairly dominant and able to resist weed invasion with minimal management. Maintenance consists of a single mowing or controlled burn in late winter/early spring and periodic monitoring for weeds.

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