What are cultural methods? Cultural methods part 1. Grazing. Disadvantages. Multi-species grazing. Controlled access and use

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1 Cultural methods part 1 Reading:Targeted grazing: chapters 6,9,&12 and skim chapter 15 What are cultural methods? Controlled access and use Grazing yes/no Grazing intensity Grazing season Recreation Other land uses Fire (prescribed fire also called controlled burns) Grazing Targeted Grazing: A Natural Approach to Vegetation Management and Landscape Enhancement Improving lands with multi species grazing Grazing to manage woody species Grazing to manage fire risk Specific examples of using grazing to manage problem plants Other examples of Bio controls Multi-species grazing Normal in much of the world Seen as more natural Rarely seen in the US Disadvantages Lack of knowledge of husbandry Lack of market for products Additional costs of equipment, fencing, labor, etc. Increased complexity of operation Lack of cultural acceptance (respect for) small ruminants 1

2 Advantages Why Increased carrying capacity Improved land condition Reduced risk due to diversification Improved animal health Reduced mortality due to predators Multiple cash flow streams Woody species Encroaching many rangelands Have defenses chemical and physical Defenses vary by time of year and growth stage of plant Goats Well suited to woody plant control Can consume some level of plants with chemical defenses Can adapt to sites and vary by breed in their tolerance for plant secondary compounds Often want short duration high intensity grazing Plants When plants are young they typically have fewer secondary compounds (sometimes it is the opposite) Before any grazing has occurred they have fewer compounds New sprouts often have fewer compounds than mature vegetation Young tissues are more nutritious (and more palatable) than mature tissues 2

3 Planning grazing Time when plants are palatable Younger plants are typically more susceptible to damage Adding a protein supplement can increase use of many problem plants Fire Rangelands and fires go together Fire suppression is still common especially along the urban fringe Fire and grazing both eat similar things Wildfire is fast and can be catastrophic and expensive Grazing is slow, returns money through sale of products, and can be managed Fire and grazing Need to know fuel characteristics Need to know species foraging strategies and forage quality of the plant community Timing is a critical component Grazing can be seen as more environmentally friendly than mechanical or chemical treatments Grazing and fire Often don t need or want enough animals for long enough to make it profitable for animal production. Also usually goats which have little market Pay to have grazing done most common along the urban-rural residential interface Give the grazing value for free more common in industrial situations, etc. 3

4 Musk Thistle - Carduus nutans Management Guidelines: Type and Class of Livestock All classes of sheep, goats, and cattle. Grazing Objective Prevent seed production, reduce plant size and vigor. Growth Stage for Treatment Graze musk thistle heavily during the rosette to bolting stage. Repeated grazing at approximately two-week intervals will be necessary to prevent flowering and seed production. May need to graze only once in a season if grazing occurs in the early flowering stage and site conditions limit regrowth. At least three successive years of grazing are needed to reduce populations. Juniper - Juniperus spp. Management Guidelines: Type and Class of Livestock Goats. Grazing Objective Remove biomass, young plants, and young stems. Growth Stage for Treatment Goats prefer seedlings or juvenile juniper plants or young regrowth from cut stems. Potential Effectiveness Goats eat younger parts of the plant before consuming older juniper. Goats can graze year round and can be very effective in controlling juniper. Essential oils, or monoterpenes, that give the plant its distinct odor can deter animals from browsing. Boer-Spanish goats tolerate the chemicals in juniper better than Angora goats. Offering a high energy/protein supplement may enhance goats acceptance of juniper. Saltcedar - Tamarix ramosissima Management Guidelines: Type and Class of Livestock Goats (especially wethers). Not recommended for sheep and cattle. Grazing Objective Severe defoliation to deplete root reserves and prevent establishment of new plants. Growth Stage for Treatment Goats have a preference for young shoots, but will readily browse shoots that are up to four years old. Repeated browsing during the season is needed to limit resprouting and to remove new seedlings. Medusahead Rye Taeniatherum caput-medusae Management Guidelines: Type and Class of Livestock All classes of sheep, goats, and cattle. Grazing Objective Graze early in season to prevent seed production and reduce medusahead mulch. Growth Stage for Treatment Graze winter rosettes in the spring. Palatability drops rapidly as plants flower and mature. Potential Effectiveness Grazing causes a decline in plant vigor and density after two years of intensive grazing. Very effective if grazed repeatedly and seed production is prevented. Grazing can be combined with a burning, mechanical methods, and herbicides. Cultural methods part 2 Reading: Living with Fire Sustaining Ecosystems & Livelihoods Through Integrated Fire Management ed_fire_management_myers_2006.pdf Fire Often used to manage vegetation Woody species Invasive species (either not fire adapted or burn is scheduled just prior to seed viability) Some system states depend on fire (usually grasslands but also some savannas and forests)

5 Prescribed Fire Program Goals Interagency Prescribed Fire Program goals are to: Provide for firefighter and public safety as the first priority. Ensure that risk management is incorporated into all prescribed fire planning and implementation. Use prescribed fire in a safe, carefully planned, and costefficient manner. Reduce wildfire risk to communities, municipal watersheds and other values and to benefit, protect, maintain, sustain, and enhance natural and cultural resources. Utilize prescribed fire to restore natural ecological processes and functions, and to achieve land management objectives. Fire-Independent Ecosystems Fire-independent ecosystems are those where fire normally plays little or no role. They are too cold, too wet or too dry to burn. Examples are deserts, tundra and rain forests in aseasonal environments Fire-Dependent Ecosystems Fire is essential and the species respond positively to fire and facilitate fire s spread (vegetation is fire-prone and flammable). Also called fire-adapted or fire-maintained ecosystems. Need a specific fire regime - frequency, intensity and season of burn. Types of fire regimes frequent, low-intensity, non-lethal surface fires mixed-severity fires (i.e. lethal and non-lethal effects varying across the landscape), infrequent, high-severity, lethal or stand replacing fires that arrest or re-set ecological succession ~46 percent of the world s priority ecoregions are dominated by fire-dependent ecosystems Fire-Sensitive Ecosystems Not evolved with fire as a significant, recurring process. Mortality is high even when fire intensity is very low. Vegetation structure and composition tend to inhibit ignition and fire spread. Fire is rare. Fragmentation, altered fuels, and increased ignitions allow fires to occur. As fires become frequent and widespread, the ecosystem shifts to more fire-prone vegetation. Tropical forests become savannas of introduced grasses and semi-arid grasslands are invaded by non-native grasses that create a continuous fuel. ~36 percent of ecoregions are dominated by firesensitive ecosystems. Fire-Influenced Ecosystems Transition zone between fire-dependent ecosystems and fire-sensitive or fire-independent ecosystems May ultimately include vegetation types where responses to fire have not been documented and the role of fire in maintaining biodiversity is not recognized. They are ecosystems that generally are either sensitive to fire but contain some species that are able to respond positively to fire disturbances, or they are ecosystems that would persist in the absence of fire but fire disturbances play a role in creating certain habitats, favoring the relative abundance of certain species, and maintaining biodiversity. Other issues with fire Cost-effective treatment over large areas Works across varied terrain Fast Dependent on sufficient fine fuel Can be spotty if the fuel load is limited. Forage production and palatability is usually increased following a burn. Seeding can be done following a burn. Erosion Fire can escape prescribed burn area Don t burn whole property at once 5

6 How to start and end a fire Fire Management on Public Forests and Rangelands A Survey of Citizens in the Central Arizona Highlands: Yavapai County Mark Brunson, Bruce Shindler, and Eric Toman Mail survey conducted in 2002 in Yavapai County Arizona (n=173) to provide managers with locally relevant information about their publics. 6

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