Forestry Miller—Chapter 23

Major Types of Forests Tropical Subtropical Temperate Polar (boreal)

Purpose of Forests Support energy flow and chemical cycling Ecological Services Economic Services Support energy flow and chemical cycling Reduce soil erosion Absorb and release water Purify water Purify air Influence local and regional climate Store atmospheric carbon Provide numerous wildlife habits Fuelwood Lumber Pulp to make paper Mining Livestock grazing Recreation Jobs

Forests Old-growth forests (frontier forests): uncut or regenerated forests that have NOT been disturbed by human activities or natural disasters for at least several hundred years Provide ecological niches for a multitude of wildlife species Second-growth forests: resulting in secondary ecological succession after the trees in an area have been removed by 1) Human activities such as clear-cutting for timber or conversion to cropland 2) Natural forces such as fire, hurricanes, or volcanic eruption Tree plantation (tree farms): Managed tracts with uniformly aged trees of one species that are harvested by clear-cutting as soon as they become commercially valuable. Then they are replanted and clear-cut again on regular cycles. Cover 5% of world’s tree cover, provide 10% of wood

Types of Forests

Types of Forest Management As the forest goes through different stages, the total volume of wood produced by a particular stand of forest varies as it goes through different stages of growth and ecological succession. Have to figure out the best way to produce fuelwood or fiber for paper production in the shortest time using a short rotation cycle Type of management depends on economy Even-aged management: Maintain trees in a given stand the same age and size. Like a small tree plantation, a old-growth or second-growth forest is replaced with 1-2 types of fast growing trees that can be harvested every 6-100 years. Uneven-aged management: Maintaining a variety of tree species in a stand at many ages and heights to foster natural regeneration. Prioritizes biological diversity, sustainability, selective cutting methods, multiple uses for forests (usually longer term)

Types of Forests

Problems associated with logging: Increased erosion and sediment runoff into waterways Habitat fragmentation and biodiversity loss Exposure of forests to invasion by nonnative pests, diseases, and wildlife species Opening of once-inaccessible forests to farmers, miners, ranchers, hunters and ORV users. If you log, can’t protect land and make it public wilderness

Harvesting Methods Selective Cutting Shelterwood Cutting Intermediate-aged or mature trees in an uneven-aged forest are cut singly or in small groups Reduces crowding, removes diseased trees Encourages growth of younger trees Maintains an uneven-aged stand of trees of different species Allow natural regeneration from surrounding trees Can help with soil erosion problems/wind damage Multi-purpose uses for forests For trees that grow best in full-to-moderate sunlight in medium to large sized clearings Removes all mature trees in 2-3 cuttings over a period of about 10 years

Harvesting Methods Seed-tree cutting Clear-cutting For trees that grow best in full-to-moderate sunlight in medium to large sized clearings Harvests nearly all a stand’s trees in one cutting, leaving a few uniformly distributed seed-producing trees to regenerate the stand For trees that grow best in full-to-moderate sunlight in medium to large sized clearings Removes all trees from an area in a single cutting Can be strip-cutting Increases timber yield per hectare Permits reforesting with genetically improved, fast-growing trees Shortens time needed to establish a new stand of trees Takes less skill and planning Max. economic return in shortest time

Types of Harvesting

Issues in Forestry Need for more sustainable growing Long rotations of 100-200 years, using selective/strip cutting, reduce road blocks, minimize fragmentation, reduce soil erosion, leave boles and snag for wildlife diversity, use tree plantations Must reduce impact of tree diseases from pathogens and insects Ban imported wood, remove/clear-cut infected species, develop disease-resistant trees, apply pesticides, IPM Forest fires Prevention, prescribed burning, presuppression, suppression, be aware of impact from climate change