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2013 NYC Envirothon FORESTRY. Saturday March 9, 2013. What is Forestry?. Propagation and management of forest trees for commercial harvest: planting and management of the existing native forests, management of invasive species, and genetic improvement of trees
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2013 NYC Envirothon FORESTRY Saturday March 9, 2013
What is Forestry? Propagation and management of forest trees for commercial harvest: • planting and management of the existing native forests, • management of invasive species, and • genetic improvement of trees Scientific study of tree growth, management and timber production
Why we need forests • Habitat for wildlife and plants • Water reservoirs and filters • Carbon sinks • Oxygen production • Regeneration of soils • Lumber • Recreation • Aesthetics
New York State Forests • ~ 18.6 million acres of New York State (62% of the state’s total land area). • 93%, or 14.4 million acres, is under private ownership. The remainder is administered by public agencies. • Timber industry provides $4 billion each year to the state economy.
What is Urban Forestry? • Planting and care of street and park trees • Restoration and management of natural forests in urban and suburban areas. • Establishment of practices for sustaining trees (management plans). • Inventory of street and park trees. • Development of urban forestry policies.
New York City Forests Mixed Forests = deciduous & coniferous Bronx: Van Cortlandt. Pelham Bay, New York Botanical Garden Brooklyn: Prospect Park Manhattan: Central Park, Inwood Hill Park Queens: Alley Pond, Forest Park, Cunningham Park Staten Island: The Greenbelt Community Gardens throughout the City Street Trees: 592,130 Park Trees (developed): 300,000
Challenges in NYC Forests • Highly fragmented ecosystem • Invasives • Exposure to pollutants • Infrastructure • Urban soils • Human caused disturbance
Forest Ecology: Tree Growth • Growth from tip of branches and down from the roots • A new trunk layer for each year. Annual rings = clues to climatic conditions during the tree’s growth. • Depend on sunlight for growth -- compensation point and shade tolerance • Photosynthetic rates correlate to temperature. Higher temperatures increase rates, to a certain point, after which a plant can "burn out".
Tree Cookie: A Slice of a Tree Trunk Sections: Outer Bark Inner Bark (phloem) Cambium Sapwood (xylem) Growth Ring Heartwood
Invasives • Non-native species, often introduced for ecological or horticultural purposes • Exotics not always harmful • Many upset natural ecological balance by out-competing local species The Tree-of-heaven (Ailanthus altissima), prolific seed production, rapid growth, overrun native vegetation, impenetrable thicket, production of toxins preventing establishment of others
Other NYC Invasives Black locust Norway maple Japanese Knotweed Multiflora rose Porcelain Berry Asian Longhorned Beetle www.pfc.forestry.ca
Tree ID & Leaf Morphology • Structure – simple vs. compound • Arrangement – opposite vs. alternate • Margins – entire, toothed, lobed • Shape – palmate, linear, elliptical, etc. • Canopy shape • Flowers • Seeds • Barks • Branching pattern Palmate
Measurements in Forestry • Species identification • Diameter at Breast Height (DBH) • Merchantable height • Lumber volume