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An Introduction to the Coastal Prairie Management Exercise. I. COASTAL PRAIRIE THREATS. Habitat Conversion and Fragmentation Invasive Species Reduced Disturbance Altered watershed hydrology Limited knowledge and under-appreciation Air pollution Climate Change.
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I. COASTAL PRAIRIE THREATS Habitat Conversion and Fragmentation Invasive Species Reduced Disturbance Altered watershed hydrology Limited knowledge and under-appreciation Air pollution Climate Change
GRASSLAND DISTURBANCE: Grazing , Fire, Digging
GRAZING By the late Pleistocene (10,000 BP to 1.6 MYBP), California grasslands supported one of the greatest wildlife assemblages on the Earth. The diversity and abundance of pre-historic grazers, browsers, predators and scavengers may be one of the greatest in the world exceeding that of East Africa (Edwards 2007).
Zebras: (Dolichohippus sp.) , (Pliohippussp.) Horses : Giant horse, Western horse, Three-toed horse Sloths: Harlan’s ground sloth, Shasta ground sloth, Jefferson’s ground sloth Bison: Ancient or Ice Age bison, Long-horned or giant bison Deer: Brachyodont deer, Mule deer, Elk Pronghorns: Pacific pronghorn, antelope or four-horned pronghorn, Pronghorn Mammoths: Columbian mammoth, American mastodon Oxen: Shrub ox, Woodland musk ox Llamas: Large-headed llama Camels: Large or western camel Tapirs: Tapir Pigs: Flat-headed peccary
Which species you graze and when you graze Bartolome, J. W., J. S. Fehmi, R. D. Jackson, and B. Allen-Diaz. 2004
Grazing Literature Summary (from Grey Hayes) • Removal of grazing changes system • Change in perennial grass abundance • Increase in shrub and tree cover • Loss of annual wildflowers • Season of grazing may matter • Type of grazer may matter • Elk similar to cow • Horse dissimilar to cattle • Type of species matters • Large site variability • Bartolome, J.
Fire prevents invasion by trees and shrubs Grey Hayes citing: Hatch, D. A., J. W. Bartolome, J. S. Fehmi, and D. S. Hillyard. 1999
Fire affects grass species differently Grey Hayes citing: Hatch, D. A., J. W. Bartolome, J. S. Fehmi, and D. S. Hillyard. 1999
Fire Summary • Removal of fire changes system • Change in perennial grass abundance • Increase in shrub and tree cover • Season of fire matters • Type of fire matters • Type of species matters • Bartolome, J.
SOIL DISTURBANCE Examples: Gophers, Bears, Pigs, Ground Squirrels, Insects Caveat: These species are also grazers!!! At a density of 23 per acre, Botta’s pocket gophers decreased the forage yield by 25% in annual-dominated rangelands in the California foothills. (Case 2008)
GOPHERS • 4 to 18 inches below the surface, deeper branches 5 - 6 ft • up to 200 yards of tunnels • up to 300 soil mounds per animal per year • up to 2 1/4 tons of earth moved per gopher each year • up to 46 3/4 tons per acre per year for a population of 50 pocket gophers • (Case 2008)
GRAZING, FIRE & SOIL DISTURBANCE • Shrub clearance • Tolerant grassland species
DISTURBANCE THEN AND NOW Significant environmental changes: Invasive species Nitrogen Habitat patchiness Climate Disturbance processes will have different effects because the environment has changed
II. MANAGEMENT PLANNING What’s a Manager to Do? “It is important that students bring a certain ragamuffin, barefoot irreverence to their studies; they are not here to worship what is known, but to question it. ” ― Jacob Bronowski, The Ascent of Man
ONE APPROACH TO GRASSLAND MANAGEMENT 1. Dispel common myths 2. Set a clear goal 3. Identify and target the “worst” and “best” species 5. Know your target species 6. Know your tools 7. Prescribe treatments that reduce the worst species and increase the best species.
Myth: If we restore historic disturbance regimes, we will restore coastal prairie.
Myth: Fire is fire and grazing is grazing. “Burning” or “grazing” are practically misnomers when it comes to describing management and restoration techniques. It is not so much that you burned or grazed, but rather when you did it, how intensive it was, whether it was spotty or uniform, and, in the case of grazing, which species did the eating (e.g., elk, cattle, goats, sheep, deer, etc.). All of these factors can influence how your grassland responds to treatments. Myths: Grazing is good Fire is good Grazing is bad Fire is bad
Myths: What works on my neighbor’s land will work on my land. What works this year, will work next year.
Myth: Researchers have figured all this stuff out.
ONE APPROACH TO GRASSLAND MANAGEMENT 1. Dispel common myths 2. Set a clear goal 3. Identify and target the “worst” and “best” species 5. Know your target species: 6. Know your tools 7. Prescribe treatments that reduce the worst species and increase the best species.
State Your Goal • Be clear about what you would like to accomplish in your grasslands. Landowners and managers may have a variety of goals they would like to achieve. This can lead to some confusion unless you are clear on what you want. • Create high-value forage for domestic livestock • Create habitat for wildlife • Create open space • Maintain firebreak around your home • Create a visually appealing prairie with high diversity of grasses and forbs
ONE APPROACH TO GRASSLAND MANAGEMENT 1. Dispel common myths 2. Set a clear goal 3. Identify and target the “worst” and “best” species 5. Know your target species: 6. Know your tools 7. Prescribe treatments that reduce the worst species and increase the best species.
Know Your Target Species How many kinds are there? Who do you want to keep and who do want to get rid of? Which species are doing the most damage to others?
1. Dispel common myths 2. Set a clear goal 3. Identify and target the “worst” and “best” species 5. Know your target species 6. Know your tools 7. Prescribe treatments that reduce the worst species and increase the best species.
Where are the growing parts and propagules? • 5 Key Characteristics to Know • longevity (annual or perennial) • when they set seed • how long seeds last in the soil • types of vegetative growth • root characteristics
Differential Longevity: Annual, Short-lived Perennial, Long-lived Perennial Purple Needle Grass (Stipapulchra) Some plants may be 100-200 years old (Hamilton, et al. 2002). Red fescue (Festucarubra) – Reproducing through tillers (and possibly short rhizomes) , forms large, long-lived individuals. The largest recorded red fescue clone was 220 meters in diameter, estimated to be over 1,000 years old (Cook 1983; Harberd 1961; Walsh 1995b).
Differential flowering and seed set FLOWERING SEEDING
Wait for them to die • Flush them out • Till them under • Cover them over Remove Seeds in the Soil
Adding Seeds • Seeding into gopher mounds – Brock Dolman “huck and chuck” • Seeding into a medium grade wood chip mulch – Kathleen Kraft Dan Davis solution
Vegetative Growth – rhizomatous vs non-rhizomatous? • Tackling Rhizomes • herbicides, • tilling, • hand pulling, • mulching and tarping
Roots • Dealing with Pesky Perennial Roots • Herbicides • Tilling • Pulling – but not all spp • Intensive grazing and trampling ? • Tarpingor Mulching?
1. Dispel common myths 2. Set a clear goal 3. Identify and target the “worst” and “best” species 5. Know your target species 6. Know your tools 7. Prescribe treatments that reduce the worst species and increase the best species.
1. Dispel common myths 2. Set a clear goal 3. Identify and target the “worst” and “best” species 5. Know your target species 6. Know your tools 7. Prescribe treatments that reduce the worst species and increase the best species.
1. Dispel common myths 2. Set a clear goal 3. Identify and target the “worst” and “best” species 5. Know your target species 6. Know your tools 7. Prescribe treatments that reduce the worst species and increase the best species: OUR NEXT ACTIVITY
Devise a strategy that will hinder reproduction and survival of the invaders relative to the desirable natives. • Grassland management is a bit like chemotherapy: you’re looking for something that may hurt all the plants, but will hurt the invaders more than it hurts the natives. • Claudia Luke