Restoration in Nevada s Rangelands. Elizabeth Leger University of Nevada, Reno

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1 Restoration in Nevada s Rangelands Elizabeth Leger University of Nevada, Reno

2 Outline Restoration in the Great Basin Can we make it better? Figure out why some plants grow better than others Implications for land management, and future directions

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9 Large scale seedings

10 Year Acres Dollars ,332 $17,468, ,363 $3,022, ,794 $1,842, ,864 $4,916, ,530 $11,119, ,878,881 $32,062, ,679,349 $11,464, ,888 $4,466, ,529 $3,300, ,227 $1,921, ,528 $7,583,311 ~$99,000,000 on Emergency Fire Stabilization and Rehabilitation projects, in 10 years, in Nevada alone BLM public land statistics

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12 1. It s the desert! Seedings often fail Why? 2. Are we planting the wrong seeds?

13 Where do Nevada s seeds come from?

14 Native grasses Native shrubs Exotic forbs Native forbs Exotic grasses Total PLS lbs. seeded Grass-focused 420 seeding treatments in Nevada,

15 Young and Larson 2005

16 Annual precipitation (inches) Planting sites dry, collection sites wet Mason, NV Nezpar Indian ricegrass Rimrok Indian ricegrass Trailhead basin wildrye Whitmar bluebunch Arriba western wheatgrass Rosana western wheatgrass

17 May 2009

18 August 2010

19 July 2011

20 Young and Larson 2005

21 Production agriculture

22 Traits prioritized in cultivar selection: Forage yield/quality Seed yield Seedling vigor Establishment and persistence Drought/semiarid tolerance High/fast germinability Large/useful adapted range Plant height Specific/uniform phenology Disease tolerance Competitive with exotic annuals Nothing mentioned Seed harvestability Genetic diversity Seed mass Sod-forming Cold tolerance Beauty Salt tolerance Good on contaminated soil Data from 90 cultivars

23 What traits will increase success in disturbed, dry places? Let s test it!

24 Learning from natural systems 1. Examine seeds that survive in restorations 2. Look at traits of surviving plants in invaded and disturbed systems

25 Do some seeds survive just by chance? Or, do some seeds survive because they are different? Compare traits in original restoration seeds with plants that establish in the field

26 Comparing survivors with original seeds Kulpa and Leger 2013, Evol. Apps.

27 Comparing survivors with original seeds Collected seeds from 100 survivors at two sites Compared to a sample of original seeds Elymus elymoides, Bottlebrush squirelltail

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29 Measurements Seed weights Plant height, leaf number, Seed production Timing of emergence, flowering Root allocation

30 Did traits differ between original seeds and surviving plants?

31 Count Count Count Seed size decreased in seeds collected from fire sites Seed weight (mg) Origin effect, P<0.001

32 Count Count Count Count Count Count Seed weight (mg) Seed weight (mg)

33 Count Count Count Count Count Count F3: x = 3.46 F3: x = 2.32 F3: x = 2.33 Seed weight (mg) Seed weight (mg)

34 Count Count Count Count Count Count Smaller seeded plants do better 40 in the field! 20 F3: x = F3: x = 2.32 F3: x = 2.33 Seed weight (mg) Seed weight (mg)

35 Count Count Count Total size Origin effect, P<0.001

36 Count Count Count Biomass (g) Total biomass F2: x = 2.25 F2: x = 1.64 F2: x = 1.67

37 Lessons learned Survival in our restorations was not random Certain plants were more likely to survive: - Smaller plant size, smaller seeds, earlier seed production, earlier emergence, greater root allocation Every restoration is an experiment!

38 Learning from natural systems part 2: Look at traits of surviving plants in invaded and disturbed systems

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41 Studying plants along invasion boundaries Leger 2008, Goergen et al. 2011, Rowe and Leger 2011

42 5 study locations

43 Five perennial grasses Poa secunda E. multisetus Achnatherum thurberianum Hesperostipa comata Achnatherum hymenoides

44 Collect adult plants from invaded and uninvaded locations 17

45 1.Are plants from invaded locations more competitive? 2.What traits are associated with increased performance?

46 Are plants from invaded areas more competitive? Yes, in 3 out of 5 sites Leger 2008, Goergen et al. 2011

47 Leger 2008, Goergen et al. 2011, Rowe and Leger 2011, Phillips and Leger 2012, Kulpa & Leger 2013, Ferguson et al. 2015, Atwater et al. 2015, Leger and Baughman 2015 Characteristics associated with increased performance? Early green-up (adults) Early flowering Early germination (seedlings) Early root growth (seedlings) Small plant size (adults and seedlings)

48 Leger 2008, Goergen et al. 2011, Rowe and Leger 2011, Phillips and Leger 2012, Kulpa & Leger 2013, Ferguson et al. 2015, Atwater et al. 2015, Leger and Baughman 2015 Characteristics associated with increased performance? Early green-up (adults) Early flowering Early germination (seedlings) Early root growth (seedlings) Small plant size (adults and seedlings)

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50 Shift to early green-up in invaded populations * E. multisetus P<0.0001

51 Shift to early green-up in invaded populations * * * * E. multisetus P< All P < Leger 2008, Goergen et al. 2011

52 Roots... Bromus tectorum

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54 Anatomy of a tenday old seedling Seed weight Growth rate Leaf area Leaf biomass Leaf number Root:shoot Root forks Root tips Fine roots Average root diameter Coarse roots Root branching Specific root length Specific root area Root length, by size class Total root length

55 Do these traits affect field performance?

56 Comparing performance among populations 35 squirreltail populations plants/population

57 First, described seedling variation in Seed size Time to emergence source populations Root 10 days Length, diameter, root tips Total size 10 day old squirreltail seedling

58 Field-testing populations in highly disturbed sites 5 planting locations 50 seeds per population per site, 1750 seeds/site

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60 Careful seed tracking

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62 Monitored: emergence, survival, size, greenness in June

63 Did populations differ in performance? Actively growing in June

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65 What do the most successful populations have in common?

66 Seed and seedling traits do an excellent job predicting success!

67 Summary and applications Every restoration can be an experiment! Invaded populations can help identify adaptive traits and serve as seed sources Field-testing performance is the most important way to chose restoration sources for seed increase A surprising suite of traits might help plants survive

68 Next steps The community!

69 Acknowledgements USDA NIFA USDA Rangeland Research Program Bureau of Reclamation University of Nevada, Reno Great Basin Native Plant Project Nevada Bureau of Land Management Dan Atwater Owen Baughman Lyndsey Boyer Erin Espeland Scot Ferguson Erin Goergen Sarah Kulpa Sandra Li Lauren Porensky Jason Sprott Courtney Rowe Bryce Wehan Lots of undergraduates!

70 Thank you!