Grazing and the Management of Conservation Rangelands

Transcription

1 Grazing and the Management of Conservation Rangelands Morgan Doran Livestock & Natural Resources Advisor University of California Cooperative Extension

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3 Beautiful vernal pool ecosystem Bad actors: Annual ryegrass, medusahead, stinkwort

4 Beautiful vernal pool ecosystem Bad actors: Annual ryegrass, medusahead, stinkwort

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6 To Graze Or Not To Graze? Many years of debate, polarized views and management decisions based on dogma. Both sides want the same outcome from their management philosophy. Healthy ecosystems Sustainable provision of ecosystem services

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10 Spanish missions in California were established from

11 Native plant species were predominantly perennial bunch grasses and annual forbs.

12 Forage species introduced by the Spanish.

13 Reality of Exotic Annuals Here to stay Exotic annuals are better adapted to grazing. Forage quality Frequency of grazing Intensity of grazing Productivity We cannot go back to a natural state. Manage for objectives with disturbance

14 Grazing References Marty, J Effects of cattle grazing on diversity in ephemeral wetlands. Conservation Biology 19: Removal of grazing decreased native vegetation and invertebrate species in vernal pools. Pyke, C.R. and J. Marty Cattle grazing mediates climate change impacts on ephemeral wetlands. Conservation Biology 19: Grazing can confound hydrologic changes driven by climate change and play a critical role in maintaining the hydrologic suitability of vernal pools for endangered aquatic invertebrates and amphibians. Bartolome, J., B. Allen-Diaz, S. Barry, L. Ford, M. Hammond, P. Hopkinson, F. Ratcliff, S. Spiegal and M. White Grazing for biodiversity in Californian Mediterranean grasslands. Rangelands. 36(5): livestock grazing appears compatible with biodiversity, but a greater understanding of the underlying site factors and site potential will be necessary for reliable prediction of management effects. Russell W. H., and J.R. McBride Landscape scale vegetation-type conversion and fire hazard in the San Francisco bay area open spaces. Landscape and Urban Planning. 64: Successional pressures resulting from fire suppression and reduced grazing have resulted in vegetation-type conversion in the open spaces surrounding the urbanized areas of the San Francisco bay area. Hayes, G.F. and K.D. Holl Cattle grazing impacts on annual forbs and vegetation composition of Mesic Grasslands in California. Conservation Biology. 17(6): The results of this and other studies highlight the importance of considering the adaptation of vegetation communities to disturbance in making grazing management recommendations. DiDonato, J Endangered Amphibian Research within Grazed Grasslands. Symposium presentation: Grazing for Biological Conservation. San Jose, CA. Amphibians evolved with disturbances associated with large herbivores and such animals continue to play an important role in these ecosystems.

15 Grazing? Grazing and No Grazing Grazing parameters are used to describe and define the type of grazing

16 Grazing The Shades of Grey Grazing Parameters Type of Animal Timing of Grazing Livestock Density Grazing Duration Manipulated to achieve desired results.

17 Feeding Behavior Lunch Buffet

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21 Taeniatherum caput-medusae - medusahead

22 Medusahead grazing trial Short duration High density Late-boot stage

23 DiTomaso et al., Invasive Plant Science and Management 1:

24 DiTomaso et al., Invasive Plant Science and Management 1:

25 Grazing Native Grasses Bobcat Ranch, Yolo County Clipping study: George et al Grazing Nassella. Rangelands

26 Grazing Native Grasses 1. First, do no harm! Avoid grazing closely and continuously over many months and years. 2. Apply early spring grazing to reduce competition from invasive annuals. a) On productive soils, use heavy spring grazing to reduce invasive species and follow with rest during flowering. b) On less-productive soils, limit heavy spring grazing to high-production years and follow with rest during flowering. 3. Graze during the dry season to create a harsh soil surface microclimate during germination and seedling establishment the following year. 4. Rest for at least 4 weeks following spring grazing to allow regrowth and tillering. 5. Rest during flowering to allow for seed set before soil moisture is depleted. 6. Avoid close grazing during growing season. Minimum stubble height of 2-4 inches will ensure regrowth and tillering. 7. If logistically difficult to apply these guidelines to all pastures, then rotate the rest treatment so that purple needlegrass can flower and set seed every few years. 8. Rotational grazing can facilitate application of these practices. Bobcat Ranch, Yolo County Clipping study: George et al Grazing Nassella. Rangelands

27 Blue Oaks and Grazing Fenced or not? Herbaceous vegetation control Tree shelters improve sapling growth Weed control improves sapling survival Damage by other animals Type and class of cattle Timing of grazing McCreary et al California Agriculture

28 Grazing Considerations Infrastructure Fencing Corrals Water Cooperative producer Objectives and goals Public education Variable weather = variable results Monitoring

29 Grazing Considerations Understand grazing cycles Understand cattle production cycles Understand cattle marketing Avoid single-objective management

30 Monitoring Realistic and affordable Residual dry matter, RDM Annual Short-term Line Point Intercept Bi- or triennial Long-term Photo point Annual or biennial Long-term

31 Monitoring Realistic and affordable Residual dry matter, RDM Annual Short-term Line Point Intercept Bi- or triennial Long-term Photo point Annual or biennial Long-term

32 Lease Considerations: Identify objectives Work with rancher to ensure practicality Incorporate flexibility Price accordingly Identify risks Public exposure and exposure to public Public livestock interactions Public education Animal health plans & protocols Drought contingency Long-term vs. short term leases

33 Practical Considerations Choose the right tool! Don t let barriers force impractical choices!

34 Practical Considerations

35 Conclusions Conversion of CA rangelands Grazing can provide ecological benefits Weed control, wildlife habitat, fire fuel reduction Grazing Grazing Grazing We must accurately and precisely define grazing parameters to replicate successes and avoid problems Grazing management is adaptive management Lease considerations Practical considerations

36 Questions Morgan Doran