Pre and Post Vegetation Management Decisions around Burning & Grazing

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1 Pre and Post Vegetation Management Decisions around Burning & Grazing Stephanie Larson, PhD Livestock & Range Management Advisor Sonoma & Marin Counties

2 Prescriptive Burning Weather Fire Spread, Severity and Intensity Landscape Features & Context Fuel Characteristics

3 Resource Goals for Your Landscapes Increase Forage for Livestock Improve Wildlife Habitat Timber Management Reduce Fire Fuel Loads Increase Native Species Decrease Invasive Species

4 Resource Management is: The use and stewardship of natural resources to meet goals and desires of humans. CURRENT FUTURE You cannot make good management decisions if you do not know the effect of past management actions.

5 Information for Resource Management Inventory = record of resources at one point in time: Land area & parcel sizes Roads & trails Water Vegetation types Corrals, building, fences Native Species Invasive Species

6 Information for Management Maps for management Vegetation map Watershed map Land ownership main/national/technical/ecoscience/desc/

7 Information for Management Assessment = evaluation of condition at one point in time: Healthy Forest Rangeland Health Ecosystem Integrity Fire Fuel Reduction Usually involve protocols based on qualitative attributes (rather than quantitative measures).

8 Tools to Management Fire Fuel Loads Prescriptive Burning Grazing Mechanical Chemical

9 Resource/ Inventory Determined by ESD (Ecological Site Description) or on ground observation, or biomass/production maps, or remote sensing of Historical use and carrying capacity. Resource Goal Ecosystem Service/Goal Process Practices Reduce dry herbaceous layer (grass and forbs) that could fuel wildfire (green herbaceous is often not very flammable); Prevent shrub invasion into grasslands; Reduce brush Reduce fire fuel load and reduce the likelihood of fire. Rangeland stewardship including effective grazing management resulting in the decrease of herbaceous biomass and prevention of the accumulation of thatch and reduce or prevent the impeding of shrubs into grasslands. Brush Management Managed Grazing Mechanical working of land Mowing Fire breaks Irrigation Planting in species that stay green through the summer (e.g. some native perennial grasses) Outcomes Reduce opportunities for catastrophic wildfire and the potential loss of structures, life (human and wildlife), and forage (is habitat a better word?) Fuel management studies have shown that spread rate and flame length are lower when dry grass fuel load is less than 800 lb./a when compared to dry grass fuel loads of 2200 lb./a (about 1 foot tall). 1 Grazing is most effective at treating smaller diameter live fuels that can greatly impact the rate of spread of a fire along with the flame height. 2 External Outcomes Prevent catastrophic events that could significantly impact water quality, increase erosion and lead to loss of structures and lives. 3 Additional Information Maintain grasslands and associated species. 3 Maintain or increase biodiversity of species including threatened and endangered. 3 Enhances diversity of grassland species, particularly increases prevalence of forbs and legumes. Reduced cost to state and local fire districts to fight wildland fire. Stabilization of Insurance Rate threat of rising rate due to risk of fire reduced. Prevent declines in air quality from fire that did not occur (or less smoke/fire if one does occur). Food and fiber and other animal by-products. California s rangelands are dominated by non-native annual species. These annual species thrive with and without livestock grazing and disturbance. As annuals left undisturbed they leave behind a thatch that can accumulate over time increasing fire fuel loads and/or decreasing the diversity of flora and fauna. Some of California s rangelands sites, left undisturbed are also subject to invasion by woody species. The combination of accumulated thatch and woody species accentuates the risk of catastrophic wildfire. Reference PES Example Challenges / Opportunities 1. Standard fire behavior fuel models: a comprehensive set for use with Rothermel's surface fire spread model, Scott and Burgan, Planned Herbivory in the Management of Wildfire Fuels, Glenn Nader, et al., October Sustainable Rangelands Ecosystem Goods & Services, Breckenridge, et al., City of Walnut Creek paying to have goats graze an area to reduce fire load. The City is paying $5800 to have goats graze 7 acres per Contra Costa Times, 7/12/2011. Typical goat grazing fee is $700 to $1000 per acre. Incidentally, cattle previously grazed the land; the City was paid $5000 by the cattle owner. The cattle were removed from the land in 2010 mainly due to complaints from parkland users that the cattle were unsafe and trampled the trails. The local residents petitioned the City to bring 03/25/13 the cattle back. As of 7/12/2011 the City decided to pay to have goats graze 7 of the 178 acres. Potential tradeoffs between fuel load reduction and benefits of RDM (Residual Dry Matter) Specific timing of managed burns may Reduce/Eliminate/Prevent spread of noxious weeds such as barb goatgrass and Medusahead.

10 Pre Fire Management~ Grazing as a Tool Amount of Live & Dead Material Biomass Composition Fuel Amounts Continuity of Fuels

11 Goal Setting Make it work for you and your property What Grazing System will achieve your goals How to measure changes and if goals reached Be adaptive how to implement changes if needed

12 Grazing Principles Which animal -Animal Species & Class How many animals -Stocking Rate When to grazing or not graze -Grazing System Match number and type of animal to the rangeland vegetation, topography and climate

13 Decision Making Strategies Natural & Human Resources Climate Topography Grazing Management Decisions Livestock Species cattle, sheep, goats or horses Community Response Vegetation Community Veg. Community Wildlife Stocking Rate how many animals Livestock Production Mgmt. Philosophy & Goals Grazing System season of grazing season of rest duration of grazing Wildlife Community Important point: Once grazing management decisions are made, there are continual interactions between livestock, wildlife, & vegetation

14 Four Grazing Management Factors: Which animal? -Animal Species & Class How many animals? -Stocking Rate When to grazing or not graze? -Grazing System Where animals graze? Grazing Distribution

15 Cost & Comparison What's the cost for fire fuel management vs. loss from fires How to choose the right tool(s) to reach your resource goals What combination of tools will best reach your goals

16 Grazing Influence these Tools Biomass Fuel Amounts Fuels Continuity

17 Post Fire Management ~ Grazing as a Tool Grazing Plan: System Infrastructures Timing & Intensity Species Frequency REDUCE THE RISK OF CATASTROPHIC WILD FIRES

18 Questions? Stephanie Larson, PhD UC Cooperative Extension Livestock & Range Management Advisor Sonoma & Marin Counties