3

Preliminary Observations

INTRODUCTION

In this chapter the committee describes its preliminary observations about key dynamics of the native seed supply that came to light in discussions with experts and practitioners and around which the committee has a partial understanding. The observations are “preliminary” because additional information is needed to confirm or correct them. These preliminary observations provide the context for the additional study and data gathering that will take place in the next phase of the assessment.

OBSERVATIONS

At this point the committee offers the following observations about the native seed supply:

Observation 1. Users have varied objectives and needs.

The users of native seed have various objectives, which may include (1) restoring native ecosystems as completely as possible, (2) stabilizing land after a severe loss of vegetation, (3) providing specific ecosystem services (e.g., soil and water conservation, pollination, invasive species control), (4) providing commercial value such as rangeland forage, and (5) beautification and native plant awareness in designed landscapes. Depending on their objectives and budget, native seed users vary in their need for and the scale at which they use provenance-specific seed mixes that are likely to become established and to survive changing climate conditions and thus to facilitate ecosystem recovery and maintain biodiversity.

Urban parks, nongovernmental advocacy organizations, and the wildlife and habitat divisions of federal and state land management agencies often conduct ecological restoration in support of their missions. The disaster recovery divisions of the large federal land management agencies (e.g., the Bureau of Land Management’s Emergency Stabilization and Rehabilitation program and the U.S. Forest Service’s Burned Area Emergency Response program) concentrate on post-wildfire emergency stabilization of land and soils and on the prevention of invasive species. State agencies frequently seek native species for specific ecosystem services, such as the beautification of roadsides or to buffer rainwater flows in bio-swales (Armstrong et al., 2017). Farmers may seek native species that provide soil and water conservation, pollination, or habitat for natural enemies of crop pests (Jackson and Meissen, 2019). Ranchers may seek species that yield high-quality forage (Staub et al., 2016).

Given the diverse objectives, motivations, and purchasing behaviors of the various users of native seed, the committee seeks to understand if, how, and when user needs are met by the current native seed supply channels. One particular concern is how the supply of and demand for provenance-specific native seed interacts with the supply of and demand for the other types of native seed that are used in many applications.

Observation 2. The seed market in the western United States is strongly affected by decision making by the large land management agencies, such as the Bureau of Land Management (BLM) and United States Forest Service (USFS).

As some of the largest buyers of seed in the United States, and possibly in the western hemisphere (Mock et al., 2016), federal land management agencies strongly influence the market for native seeds. The committee is interested in understanding more about the determinants of seed choice and the decision-making processes concerning ecological restoration in these agencies, which vary both among the agencies themselves and even among different divisions within a single agency (e.g., BLM field offices, USFS districts).

In the USFS, post-fire seeding varies by region, but overall the practice has declined, reflecting policy decisions to avoid non-native seeds and to not seed areas considered capable of regenerating naturally (Erickson, 2019). The current emphases are wildfire mediation and control, timber sales, and fuel reduction. Although expanded native seed restoration is recognized as a critical component of forest management, and there is an official native seed policy, there is no agency-wide native plant restoration program.

In the BLM, post-fire seeding has generally emphasized grass-dominated mixes for stabilization rather than diverse mixes designed for longer-term ecological restoration. Seed mixes appear to be chosen by considering site conditions and historic vegetation and by consulting fire rehabilitation plans from nearby burn sites. The same mix is often applied on multiple sites for cost efficiencies. Seeds are procured through the consolidated seed buys, records of which show an ongoing reliance on non-natives, natives that are not specific to the local site, and limited but increasing requests for materials from specific seed zones.¹ The committee learned that the BLM seed selection process relies strongly on past practices; the contributing reasons include staff turnover, limited training, short timelines for project approval, and limited budgets. The monitoring of seeding projects is typically short-term (2–5 years), although the duration and intensity varies among projects. As a result, it is not always clear whether seeding has been successful or whether natural recovery has occurred. If a restoration project is unsuccessful, there is typically no further funding to continue the work. However, the success or failure of the project (and the practices employed) does not affect funding for future projects. A new database, TerrADat, is currently being used by some field offices to store monitoring results, which may provide an opportunity to use monitoring results to inform future decisions (BLM, 2020).

Large-scale, proactive restoration projects have not historically been the norm in either the BLM or the USFS, although the multimillion-dollar efforts to restore sage-grouse habitat and manage fire risks in the Great Basin are becoming important exceptions. The committee learned anecdotally that some federal agency practitioners have been able to succeed in carrying out proactive native seed-based restoration through collaborations with state wildlife agency partners (such as in Nevada and Utah) using a variety of ad-hoc funding sources, financial instruments (contracts, agreements), and applied science tools to assist in seed selection, collection, production, and procurement. As one example, in Idaho the BLM has used the Integrated Program of Work element of the fuels program to request additional support for particular seed mixes (BLM, 2019). Rather than changing traditional agency practices, it appears that a series of ad-hoc “work-arounds” are being developed, which may be effective for their purposes but are

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¹ Unpublished reports from BLM consolidated seed buys are available upon request from the National Academies Public Access Records Office.

currently outside the main funding and planning streams. Whether these innovations could provide models for expanding proactive restoration work by the agencies, and how such an expansion might affect the native seed market, requires further exploration.

Observation 3. Timeframe, quantity, and quality strongly limit the overlap between what seed is available and what seed is desired.

Both the BLM and USFS have policies that emphasize the need to use native seed for restoration projects, but exceptions are allowed and indeed are common in the BLM. Much of the agency’s demand for native seed arises suddenly in response to large wildfires or other large-scale events, and these large and reactive needs are much harder to meet than are proactively planned needs. Some of the seed demand may be met by the agency’s own inventories, but large fires also create the need for rapid procurement of large quantities from commercial sources, and the scale and urgency of demand are likely to affect prices and availability. In this setting, BLM and USFS practitioners frequently lean on policies that allow the use of substitutes, including non-native species or native cultivars, when provenance-specific native seeds are not available (Camhi et al., 2019; Peppin et al., 2010). By contrast, proactive demand for provenance-specific native seed has a longer time horizon and thus allows more options for finding or developing sources of seed that meet agency preferences.

The availability and prices of provenance-specific seed are likely to be strongly affected by the balance between reactive and proactive demand. Given that wildland fires and other large-scale events will continue to be important drivers of seed demand, the committee will explore the problem of timeframe and urgency as it relates to the availability of all types of native seed. Although emergencies drive need, better advanced planning for emergencies may be possible using knowledge of the locations of fire-prone landscapes. Support for proactive restoration may also help create the supply needed for emergencies.

Observation 4. Seed choices do not always support restoration success, and outcomes do not always inform choices.

The committee is also interested in how seed choices influence the success of ecological restoration. Seeding for restoration may not meet all stated goals: the seeds may not germinate, or the plants may not persist, or the plants may persist but not fulfill the objective of recovery of biodiversity, failing at such specific tasks as controlling invasive species or reestablishing self-sustaining native plant populations.

On public lands in the western United States, where many very large-scale seeding projects have taken place, it is common for seeds to fail to become established, especially in warmer and drier locations (Arkle et al., 2014, Knutson et al., 2014, Pilliod et al., 2017). One of the major contributors to seeding failure is the use of seeds that are not well matched to the local climate (Baughman et al., 2016; Germino et al., 2019; Rowe and Leger, 2012); other factors in seeding failure include such things as site preparation and planting methods, timing, weather (including timely precipitation), and the presence of weeds, including those that might be present in the native seed lot used. For most species, local populations are usually better adapted to local environments than those from more distant environments (Baughman et al., 2019). Establishing plants in more extreme hot and dry environments is particularly difficult, but seed from populations adapted to such extreme environments are often scarce, which frequently leads to a

reliance on natives from dissimilar geographic origins or non-native plant seeds, which end up failing to meet restoration objectives.

Grasses, both native and non-native, have been heavily emphasized in seeding projects on western U.S. public lands (Olwell, 2019). Grasses are preferred on lands with active grazing allotments because of their forage value. Grass seeds are relatively easy to propagate in agricultural settings using equipment and techniques developed for exotic turf and forage crops. Grasses tend to germinate readily, grow quickly, and compete strongly with other plants. However, these same attributes may lead seeded grasses, particularly non-native grasses, to inhibit the recovery of other indigenous grasses, shrubs, and forbs that are naturally present in seeded sites (or are co-seeded with grasses). Grasses contribute substantially to, but do not meet all of the needs of, wildlife and pollinators, nor do they perform many of the essential ecological functions of shrubs and forbs. Although shrubs and forbs are increasingly being added to seeding mixes, only a few such species are available for seeding in large quantities (Pilliod et al., 2017). Cost, training needs, and the lack of seeding techniques for establishing mixtures of species are additional impediments to the ongoing effort to increase the use of shrubs and forbs for multiple restoration goals (Shaw et al., 2005).

Observation 5. The budgets and seed specifications of users vary greatly, as do the unit costs of suppliers.

Budget constraints often limit the ability of native seed users to meet their needs in the marketplace. Budgets available to native seed users appear to vary tremendously, as does the mix of native plant genetic attributes that buyers seek. Users’ budgets may be affected by funding source, timeframe, project location (urban versus rural), project scale, project priority, and whether the project has legal requirements (for example, restoration following resource extraction).

Native seed buyers also vary in their goals for their planting projects and, hence, vary in the diversity of species and seed traits that they need. Some projects aim for the ecological restoration of ecosystems and may seek a broad set of natives species that show local adaptation and are likely to perform well in a given site. Other projects may have narrower goals, such as to plant native vegetation that supports pollinators or promotes soil conservation. More information is needed on the relationship between budgets and the desired seed specifications in shaping buyers’ purchasing decisions. Across all native seed buyers, the willingness to pay for native seeds might be envisioned as a continuum, ranging from a high willingness for buyers with well-funded projects with specific restoration objectives to a low willingness in the case of less well-funded projects with more flexible objectives. The committee will investigate the range of factors that shape buyer willingness to pay for different types of seeds.

From conversations with seed producers, the committee understands that the commercial availability of native seeds is shaped by their costs of production. The costs of production vary by species and depend on factors such as how easily the species can be grown agronomically and commercially collected, how long it takes for plants to reach seed-bearing age, the seed yield for the species, and the costs of labor, equipment, and other inputs needed for seed production of a particular species. In addition, seed suppliers bear the costs of harvest, storage, marketing, and financing (Kleiner, 2019; Terrell, 2019). These costs appear to vary by geographic region, producer scale, and the species and native plant genetic attributes that suppliers are trying to produce. For example, it may be less costly to produce an agronomically successful cultivar of a

native species than to produce several genetically diverse local populations of the same species that have a more limited market.

The committee would like to understand better the costs per unit of native seed production for suppliers to meet different kinds of buyer specifications. The costs conceivably vary according to different production-related factors, with low-cost seeds being those that are easy to cultivate or collect, while higher-cost seeds are more difficult to cultivate or collect. The committee feels that it will be essential to carry out an empirical assessment of how production costs shape the willingness and abilities of producers to supply native seeds at different prices and buyer specifications.

Observation 6. Seed procurement may be hampered by market volatility, risk, and contract structure.

Seeds are procured through direct purchases and by contracts (Olwell, 2019). The committee plans to investigate the behaviors of buyers and sellers of native seed under different procurement scenarios. There are features of the native seed market that economic theory predicts should make it quite volatile. Some suppliers collect wildland seed or produce seed in cultivated fields speculatively, without a contract, in an attempt to predict highly uncertain future demand for specific species (Camhi et al., 2019; Peppin et al., 2010; Taylor et al., 2018).

Timing is a critical contributor to market volatility. The interactions between the multi-year seed production cycles and the demand for appropriate seed, including the extent to which storage is used currently and the potential for its expansion, are essential in assessing market risks. However, many prospective and current growers are unwilling or unable to bear the risks of both producing native seeds and of carrying inventories in the face of uncertain demand (Taylor et al., 2018).

The committee observed that buyers sometimes encounter difficulty in finding seed that meets their specifications (quantity, quality, genetic composition), especially when demand is urgent. It is possible that this urgency incentivizes suppliers to produce species and genotypes that can be grown across a broad geographic area in order to increase the likelihood that they will be able to sell their inventories. For some buyers, the costs for the preferred seed may be too high (Peppin et al., 2010). As noted above, how buyers with limited budgets respond to seed prices needs further exploration. Assuming that buyers know what they want to achieve and understand how the seed is likely to perform, do they, for example, decide to substitute less costly seed over a large acreage or use more expensive seed but on a smaller area? And do limited buyer budgets induce suppliers not to produce native seeds that would be too costly, particularly when some funds are released only under emergency conditions?

Native seeds are sometimes procured through contracts, including government purchases, as noted in the discussion of seed and plant production in Chapter 2 (Olwell, 2019). Economic theory predicts that market characteristics affect how well different types of contracts will work. Three such characteristics that appear to merit further investigation based on information collected to date: (1) the volatility of demand for native seeds and their associated quantities, as observed specifically for BLM purchases (Olwell, 2019); (2) the relationship, if any, between the diversity of species for which seed is needed (and the specificity of the seed zone) and the volume purchased; and (3) the importance of transaction costs and required contract provisions for designing a contract that both buyers and suppliers find attractive. Transaction costs include the efforts exerted by buyers and sellers to communicate needs and availability as well as to

agree upon terms of sale. In light of the importance of transaction costs, BLM identified communication tools as a challenge it would like the committee to address (Olwell, 2019).

A clearer understanding of the market conditions affecting contracts could help in designing contracts that would improve the responsiveness of native seed suppliers to seed needs. For example, the duration of a contract may influence its suitability for specific relationships. Risk sharing is another contract design decision that can influence its suitability. There are different ways of sharing risk. For example, sharing production costs is one way of sharing risks. Guaranteeing a purchasing “home” for all production (in which, for example, the buying agency takes the risk that some seed will never be used and have to be destroyed) is another. Perhaps agencies could facilitate the seed purchases of smaller public or private entities in order to smooth demand in years when natural disasters are not driving the need for seed. Thus one important question is, How can contract designs serve both buyers and sellers, and what kind of contracts work best under the range of market conditions that prevail for native seeds?

Observation 7. The seed market may be strongly affected by a limited capacity for seed banking and for adequate and appropriate storage conditions.

Because provenance-specific natives are frequently in short supply when they are needed to respond to a natural disaster, it might be useful to stockpile seeds so that they are available when needed. However, to stockpile seeds effectively would require adequate and economic seed storage capacity, the ability to forecast which areas are most likely to need seeds, and the ability to keep storage seeds viable long enough to respond to any need for prolonged periods.

Seed longevity depends on the species, initial seed quality, and storage conditions. Most plants (approximately 75–80 percent), including most western U.S. restoration species, produce seeds that can, with proper drying, withstand freezing that lengthens their viability (Walters et al., 2013). For these species, seed longevity can be approximately doubled for every 1 percent decrease in relative humidity and 5 °C decrease in temperature, within limits. Seeds stored at ambient conditions remain viable for a few months to about 10 years, but seed dried at low humidity and stored at -18 °C can last, on average, 200 years, and seed refrigerated at 4 °C falls in the middle of this wide range (Walters, 2004).

Seed companies have some limited cold storage for the short-term storage of native seed, but the long-term, multiple-year storage of seed requires the conditions noted above (low humidity and low temperature) at special facilities. Such facilities are currently limited in size and number. Furthermore, in many cases best practices for the long-term seed storage of native plant species are poorly understood.

The key questions for the committee in this are how much storage is available, how much expanding storage capacity could reduce the volatility of the seed market and the price of seeds, and what measures could be taken to expand storage capacity.

Observation 8. Issues affecting urban, Midwestern, and Eastern settings are somewhat distinct from those affecting public lands in the West.

Midwestern and Eastern U.S.

The committee has only begun to explore the nature of the seed supply outside of the Western states, but some fundamental differences are apparent. In contrast to the 11 western U.S.

states, where the federal government manages more than 40 percent of all land (Shaw, 2019), the largest users of native seeds in the midwestern and eastern United States are smaller entities: state, county, and municipal agencies; nonprofits; and public–private partnerships addressing such issues as pollinator conservation, wildlife habitat, invasive species control, and farmland nutrient management. For example, invasive species councils in each of New York State’s seven subregions conduct state-funded programs for which they seek appropriate native plant seeds (NYS DEC, 2016). The potential may exist for these entities to expand the supply of native seeds through improved planning and coordination of their activities, such as by mitigating the barriers imposed by procurement policies. Extension programs in many states have master naturalist programs, and in Maryland the master naturalists have worked to produce native provenance-specific bulk seed.² These programs educate the public on the importance and need for native plants. The committee will explore opportunities and constraints for increasing locally adapted native plant seeds, particularly in the East.

In urban areas, project planning, design, and implementation are typically done by landscape architects and, to a lesser extent, by engineers. While these design professionals vary in their exposure to ecological principles, they are increasingly specifying provenance-specific plant materials. A survey of landscape architects, such as members of the American Society of Landscape Architects,³ may be valuable for better understanding their uses of native species.

Hurricanes and flooding are creating an increasing demand for large-scale restoration in the eastern United States, analogous to the fire-driven demand for restoration on western U. S. public lands. The native plant material supply chain is generally inadequate to meet these large demands. New York City’s municipal native plant nursery and seed bank were in place prior to Hurricane Sandy in 2012 and have been able to serve recovery efforts, but this case is an exception. Disaster recovery has also spurred resiliency planning aimed at making urban areas less vulnerable; the largest such initiative is the Mississippi Cities and Towns Initiative, which includes 64 cities located along the Mississippi River. Although rarely considered in the planning stage of these initiatives, native plant supply chains will be essential to their success. Thus it will be important to develop a better characterization of the potential future demand for native plant materials in the context of large climatic events and resilience planning.

The native plant material supply chain for the eastern United States is also affected by several regional-scale constraints. First, because of the humid climate seed warehousing is more challenging. There are no public sector seed warehouses in the eastern United States that are capable of storing significant quantities of bulk seed. Second, there are only a handful of institutions, such as the USFS and Mid-Atlantic Regional Seed Bank, that conduct seed collection, processing, and banking in support of creating a sustainable supply of ecoregional native plant seeds. Outside of these institutions, most seed collection is done on a short-term, individual, or project basis, or it is done by commercial entities with no standardization, regulation, or use of available native seed programs, as is also true of much of nursery plant production.

Urban Wildlands and Other Urban Issues

Natural and semi-natural areas in and around cities often support considerable biodiversity (Aronson et. al., 2017) which provides desirable services to humans. In addition to

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² See https://extension.umd.edu/masternaturalist.

³ See https://www.alsa.org/ecology.aspx.

the threats facing all wildlands (e.g., habitat loss, fragmentation, invasive species), these urban wildlands are subject to climatic disturbances, such as flooding and drought, that may be intensified by the surrounding expanses of impervious surfaces typical of urban landscapes.

Restoration in virtually every urban center depends on native plant materials from distant sources; a 2018 survey of eastern native plant materials users found average distances to suppliers of 375–415 miles, even though 74 percent of users expressed a preference for local ecotypes.⁴ Urban centers rely much more heavily on live plant material than on bulk seed in managing urban ecosystems, but bulk seed use is on the increase, which may create a need to expand the supply.

Urban restoration often involves a network of regulatory and management entities at multiple levels of government (municipal, state, federal) as well as NGOs. For instance, in New York City at least 19 agencies from all levels of government may be involved in the funding or oversight of restoration projects. The complexity of these networks, each with its own set of planning rules and procurement policies, often leads to delays and difficulties in the native plant materials supply chain. The committee will explore what opportunities exist for improving the availability of native plant materials for urban wildland restoration projects.

Private residential uses of native plants are growing in urban and suburban areas as landscape professionals and homeowners are increasingly using native plant materials in their home landscaping. Popular literature as well as concerns for bird and pollinator decline are adding to this demand for ecoregional plant materials in the home landscape (Murray, 2019). There is also a growing market for native plants for green roofs in urban areas (DiNardo, 2019). Among other issues, an understanding is needed of the extent that these small-scale private uses can help move new species into the market and stabilize markets for larger scale uses.

SUMMARY

The market for native seeds reflects a diverse and distributed system of buyers and suppliers that operates in the face of multiple constraints. This chapter touched on many of those constraints and other features of the native seed enterprise that the committee seeks to explore further in the next phase of the assessment. In Chapter 4 the committee will describe the next steps it plans to take to obtain information needed for further analysis.

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⁴ See http://www.marsb.org/sosmemberinfo/survey-native-plant-and-seed-use-in-the-eastern-u-s.

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