This document discusses guidelines for selecting genetically appropriate plant materials to enhance biological diversity in restoration projects. It emphasizes various considerations, such as project goals, species characteristics, genetic status, and the implications of using local vs. non-local sources. The document advises careful evaluation of genetics and ecological contexts to avoid potential negative outcomes from improper species introductions.

1. Genetically Appropriate Choices for Plant Materials to Maintain Biological Diversity Arlee M. Montalvo Department of Botany and Plant Sciences, University of California, Riverside and Riverside-Corona Resource Conservation District

2. Acknowledgements Andy Kratz, Norman Ellstrand, Sue Mazer, Mary Mahalovich, Gay Austin, Len Nunney, Nick Waser, Laura Galloway, Ruth Shaw, Vicky Erickson, Steve Monsen, Randy Johnson, Patrick McGuire, a bunch of reviewers and many others, especially co-author Deborah Rogers. The USDA Forest Service, Rocky Mountain Region provided funding and logistical support for “the Guide”: To find “THE GUIDE” Rogers, D.L. and A.M. Montalvo. 2004. Genetically appropriate choices for plant materials to maintain biological diversity. University of California. Report to the USDA Forest Service, Rocky Mountain Region, Lakewood, CO. Online: http://www.fs.fed.us/r2/publications/botany/plantgenetics.pdf

3. For Genetics Part of Ecological Restoration Goal, What Matters? Preserving processes and all levels of biodiversity Providing potential for future survival and evolution Looking at how the site fits into surrounding landscape Dispersal linkages among fragmented populations Looking backwards and ahead Preserving species interactions Minimizing detrimental species/population introductions Avoiding problematic cascading effects Avoiding inbreeding and outbreeding depression Protecting genetic reserves and research potential Plant material availability, cost, logistics

4. Species Selection Source Selection Choice of plant species and project goals are of vital importance This talk focuses on steps that follow those important first steps Here, the focus is on diversity within species and choosing source populations Sometimes, looking deeper will lead to revision of species choices -- or goals

5. Factors to Consider in Selection of Sources • Goals and implications of restoration project • Habitat and population conditions Species characteristics-- life-history, mating system Population characteristics • Landscape ecological relation of donor and recipient sites • Collection and propagation protocols (see Guide chapt. 8) • Genetic status of donor and recipient populations • Population or species knowledge • Project parameters, including logistics and funding

6. Steps for informing choices (Rogers and Montalvo 2004) Identify project objective Determine project context Is natural regeneration sufficient to render introductions unnecessary? Is the species threatened or endangered? Are there seed transfer rules? Is the species clonal? Is there evidence of genetic differentiation or local adaptation? Is the species polyploid? What is the main breeding system? Mating system? Is there evidence of inbreeding or outbreeding depression? Site considerations Address selection of plant introduction stock Address whether or not to introduce plants Slide modified from Johnson & Roy 2006

7. Steps for informing choices (Rogers and Montalvo 2004) 1. Identify project objective 2. Determine project context Is natural regeneration sufficient to render introductions unnecessary? Is the species a state or federally listed species? Are there seed transfer rules? Is the species clonal? Is there evidence of genetic differentiation or local adaptation? Is the species polyploid? What is the main breeding system? Mating system? Is there evidence of inbreeding or outbreeding depression? Site considerations

8. 1. Is a major goal the maintenance of native plant species to support natural levels of biodiversity? Yes– proceed to step 3 (is natural regeneration sufficient?) No– proceed to step 2 2. Is the project isolated from areas with similar biodiversity goal? Yes– proceed with discretion and use genetically appropriate materials as much as possible No– proceed to next step 3 (is natural regeneration sufficient?)

9. Spatial Context, Scale, and Connectivity of Sites introduced genotypes to go into striped areas dotted or graded areas are part or all of species distribution A B D C

10. Consider Landscape Scale Strategies at all Steps Prevailing Wind during bloom period Plant propagule source reserves Planting in buffer zones of reserve (encourage use of reserve propagules) River flow direction Restoration site Restoration site Big hills Slide modified from Johnson & Roy 2006

11. Bailey’s System: ww.fs.fed.us/colormap/ecoreg1_provinces 200 Humid Temperate Domain 220 Hot Continental Division 221 Eastern Broadleaf Forest (Oceanic) Province

13. www.epa.gov/wed/pages/ecoregions/level_iii.htm 84: Atlantic Coastal Pine Barrens 50: Northern Lakes and Forests 58: Northeastern Highlands 64: Northern Piedmont

14. Steps for informing choices (Rogers and Montalvo 2004) Identify project objective Determine project context 3. Is natural regeneration sufficient to render introductions unnecessary? Is the species threatened or endangered? Are there seed transfer rules? Is the species clonal? Is there evidence of genetic differentiation or local adaptation? Is the species polyploid? What is the main breeding system? Mating system? Is there evidence of inbreeding or outbreeding depression? Site considerations

15. After Disturbance, Always Consider Extent of Natural Regeneration Soil seed bank Canopy seed bank Corms, bulbs and other propagules Resprouting from stumps, roots, rhizomes Natural seed rain Also consider ability of particularly bad invasive species to take hold first

16. Steps for informing choices (Rogers and Montalvo 2004) Identify project objective Determine project context Is natural regeneration sufficient to render introductions unnecessary? Is the species a state or federally listed species? Are there seed transfer rules? Is the species clonal? Is there evidence of genetic differentiation or local adaptation? Is the species polyploid? What is the main breeding system? Mating system? Is there evidence of inbreeding or outbreeding depression? Site considerations

17. Steps for informing choices (Rogers and Montalvo 2004) Identify project objective Determine project context Is natural regeneration sufficient to render introductions unnecessary? Is the species threatened or endangered? Are there seed transfer rules? Is the species clonal? Is there evidence of genetic differentiation or local adaptation? Is the species polyploid? What is the main breeding system? Mating system? Is there evidence of inbreeding or outbreeding depression? Site considerations

18. What is a seed transfer seed zone? An area with defined boundaries and altitudinal limits often based on soil, climate and geography, within which seed (plant material) can be moved with minimal risk of maladaptation Can improve on concept “ Geographical regions within which individuals of native species can be transferred with no detrimental effects on population mean fitness” (Hufford & Mazer 2003)

19. Late 1930’s – First seed zone maps Geographic and climatic data were used to define ‘unique’ regions in the Pacific Northwest Assumed plants affected by climatic variables Grouped areas with similar climate and vegetation One map for all tree species Can and have improved on this

20. www.epa.gov/wed/pages/ecoregions/level_iii.htm Level III units can be further subdivided based on details of soil, elevation, evapotranspiration, and vegetation

22. USDA Hardiness Zones

23. Foresters began creating a system for species-specific seed transfer long ago Long-term provenance trials in the US were established as early as 1911. Such reciprocal transplant trials have revealed genetic differences Morphology Physiology Phenology Fitness traits Takes a long time Not many around Mostly conifers

24. Nassella pulchra, purple needlegrass Basic model: V P = V G + V E in common garden: V P ~= V G Elymus glaucus Traditional Common Garden Studies (Knapp & Rice; Erickson & Sorenson)

25. Foresters grew seed sources from diverse areas (provenances) in several common environments

26. Long-term provenance trials provided evidence of the problems that could occur when using the wrong seed source A 1955 cold snap in early November led to the decline of off-site Douglas-fir provenances in a trial established in 1915 It’s the rare climatic events that tend to show maladaptation in long-lived trees

27. Researchers determine which environmental and climatic variables from the seed source locations correlate with traits measured in the study plots example of stepped cline in ponderosa pine (Sorensen and others 2001 ) Data provided by G Randy Johnson, USFS Data often show geographic patterns in morphology and fitness-related traits

28. Seed-collection zones for Pinus echinata , shortleaf pine (Wells 1979) See Guide, pp 120-121 for ponderosa pine

29. Pinus echinata , shortleaf pine Wide geographic range– in 22 states Southeastern NY and NJ to PA, s. to n. FL Temp. extremes: -22 o F in NJ to 112 o F in LA Wind pollinated Wind dispersed seeds, avg. 250 feet, max ¼ mi. Geographic cline in pollen size Genetic studies done after initial seed zones made

30. Improve Seed Transfer Guidelines with Genetic Data Data on adaptive differences Performance data from reciprocal transplant and common garden studies Patterning in plant traits and correspondence to environmental patterns Data on more neutral genetic differences Patterns in molecular genetic data that indicate aspects of gene flow and history of populations Geographic patterns in molecular data (phylogeography)

31. Common garden tests showed continuous (clinal) variation with elevation and latitude in morphology and important ecological variable such as disease resistance, length of growing season, response to day length, and dormancy.

32. Geographic Patterns in Liriodendron tulipifera Patterns suggest post Pleistocene differentiation following dispersal from single glacial refugium recontact and hybridization in sympatry Similar patterns proposed for several conifer species following detailed phylogeographic work

33. Also Consider Performance of Hybrids

34. Steps for informing choices (Rogers and Montalvo 2004) Identify project objective Determine project context Is natural regeneration sufficient to render introductions unnecessary? Is the species threatened or endangered? Are there seed transfer rules? Is the species clonal? Is there evidence of genetic differentiation or local adaptation? Is the species polyploid? What is the main breeding system? Mating system? Is there evidence of inbreeding or outbreeding depression? Site considerations

35. Life History Traits

38. Steps for informing choices (Rogers and Montalvo 2004) Identify project objective Determine project context Is natural regeneration sufficient to render introductions unnecessary? Is the species a state or federally listed species? Are there seed transfer rules? Is the species clonal? Is there evidence of genetic differentiation or local adaptation? Is the species polyploid? What is the main breeding system? Mating system? Is there evidence of inbreeding or outbreeding depression? Site considerations

39. Choice of Plant Materials and Effects of Mixing Populations Beneficial Effects Genetic rescue Introgression of new beneficial genetic combinations Possible heterosis Adverse Effects Mating incompatibilities Dilution of adaptation Hybrid breakdown and lower fitness for multiple generations Swamping Likelihood of effects depends on magnitude of genetic differentiation, life histories, particular genetic architectures of source and recipient populations, site conditions

40. Is There Data on Target Species or on Species with Similar Traits? Do outstanding genetic differences among populations influence their survival and reproduction in different environments? Have recipient and source populations been isolated for a very long time? Are actual or potential genetic differences among populations large enough to decrease success of mating and hybrid offspring?

41. Low structure correlates with high gene dispersal and consequently high similarity of populations (but with isolation by distance)

42. Effect of Crossing Distance on F 1 Fitness for 66 Studies Comparing Crosses Within and Among Populations 55% of studies showed lower fitness of hybrids than parents (OBD). 32% showed heterosis. 14% showed no effect of crossing distance. 96% of 49 studies tested for and found inbreeding depression. table built in 2001-- can add more data now-- including for > 1 generation-- eventually can test for expected patterns with life-history

43. Other Methods are Being Devised to Assist in Making Choices A ‘Rapid Assessment’ method (Johnson and Roy) is being devised that may prove useful Uses data and generalizations Must recognize limitations and course nature of generalizations based on life history Some regions are amassing data and looking at patterns in many plant species for defined area See Native Seed Network web site

44. Bart Johnson and Bitty Roy (2006 in prep.) Genetic Effects Rapid Assessment Matrix To identify potential undesirable outcomes from introduction of off-site plant stock Matrix logic: all else being equal, effects of increasing distance* of propagule source from introduction site are such that: a) Distance is less likely to be a problem for success on site for outcrossers than for selfers b) Distance is less likely to lead to undesirable genetic effects on site or nearby for selfers than for outcrossers c) The consequences of undesirable genetic effects on site or nearby are greater for sensitive species and those which are more likely to hybridize d) Species with small populations relative to the introduction are more vulnerable to genetic swamping and genetic load. e) When the species is not extant on site or nearby, the issue of undesired genetic effects is minimal for the initial introduction * To extent possible distinguish between physical distance, environmental distance and effective dispersal distance

45. Genetic Effects Rapid Assessment Matrix Codes: DP = Distance problematic DLP = Distance less problematic NP = Distance not problematic -- or ++  lesser or greater likelihood for problems Matrix tracks two issues: success on site and potential for undesirable genetic effects Slide modified from Johnson & Roy 2006

46. Genetic Effects Rapid Assessment Matrix Codes: DP = Distance problematic DLP = Distance less problematic NP = Distance not problematic -- or ++  lesser or greater likelihood for problems Elymus glaucus Slide modified from Johnson & Roy 2006

47. Genetic Effects Rapid Assessment Matrix Codes: DP = Distance problematic DLP = Distance less problematic NP = Distance not problematic -- or ++  lesser or greater likelihood for problems Roemer’s Fescue Slide modified from Johnson & Roy 2006

48. Genetically Local? “Plant materials that reflect the amount and type of genetic diversity that is typical for a particular plant species in the area under consideration” Physical distances and risks are variable Can also consider effects on other species Area associated with minimal risk of extinction

49. Steps for informing choices (Rogers and Montalvo 2004) Identify project objective Determine project context Is natural regeneration sufficient to render introductions unnecessary? Is the species a state or federally listed species? Are there seed transfer rules? Is the species clonal? Is there evidence of genetic differentiation or local adaptation? Is the species polyploid? What is the main breeding system? Mating system? Is there evidence of inbreeding or outbreeding depression? Site considerations

51. Challenges for using evolutionary-based, ecological restoration to maintain biodiversity When in doubt, play it safe………. There are potential benefits and risks from broad-scale mixing of genotypes, but lower risks with local-scale mixing For drastically altered sites and population fragmentation, in the face of extirpations, looming climate change, and economic constraints, it may seem desirable to do broad-scale mixing of genetic materials and “let natural selection sort it out” • Keep in mind: choices made in the face of limited knowledge or funding can be risky and result in long-term consequences Choosing genetically local sources may maintain multiple levels of genetic diversity from genes to populations to communities and ecosystems. Managed gene flow will require looking at historical patterns and future projections

52. Native Cultivars: Considerations Why and how was the material produced? What are the main issues? Agricultural vs ecological goal Genetic erosion, genetic diversity, hybridization How can cultivars be used responsibly? What should you know about the cultivars you consider for use in restoration? See chapter 8 of guide……and Aubry, Shoal, and Erickson (2004)

53. Ends Along a Continuum: Source adapted or general purpose? Narrowly adapted ecotypes or accessions: maximize GxE retain coadapted gene complexes preserve complex species interactions inbreeding depression risk if too narrow Broadly adapted cultivars: minimize GxE agricultural trait syndrome ignore coadaptation & interactions outbreeding depression risk Modified from Chris Richards

54. Knowledge of Plant Material Releases Initial sampling and collection methods? Diversity in collections? Inbreeding avoidance? Sampling modified for mating system? Clonality? Selection of phenotypes? Produced with agricultural or ecological goal? Was there intentional selection of genotypes? Broadest ecological tolerance and lowest G x E? Highest growth rate? Palatable forage or digestibility by sheep or cattle? Heavy metal tolerance? Selection of phenotypes may result in unforeseen tradeoffs (e.g., disease resistance, drought tolerance)

55. Knowledge of Plant Material Releases Unintentional selection potential (generation no.)? Loss of seed dormancy and seed shattering Narrowing of or shift in flowering time Loss of genetic variance Is genetic diversity of accession narrow? Is genetic diversity broadened by mixing accessions? Did seed zone research guide mixtures? Recognition of species interactions? If goal is F1 heterosis, was hybrid breakdown or environmental dependence studied? Cross contamination during grow out? Did isolation distance recognize variation in mating system?

56. Consider Landscape Context of Project How can managers mitigate unknown risks? Consider the context of planting project urban rural-agriculture, little native vegetation leapfrogs wild and developed habitats urban-wildland interface wildlands (heterogeneous vs homogeneous) proximity to research and germplasm reserves proximity to related rare species