Effects of Biomass Production and Harvesting on Environmental Quality Erik B. Schilling National Council for Air & Stream Improvement Southern Regional Center Newberry, FL

General Facts  Currently 32M acres of plantation forests in SE US Predominately Loblolly Pine, lesser extent Slash Pine Predominately Loblolly Pine, lesser extent Slash Pine  SE US average growth rate of 5 tons ac -1 yr -1 This is much less than many forest plantations throughout the world This is much less than many forest plantations throughout the world  Models, field trials, etc. indicate that growth rates exceeding 10 tons ac -1 yr -1 are biologically feasible.

Increasing Growth Rates  Genetics Improve desired ecophysiological traits Improve desired ecophysiological traits Leaf area, water and nutrient use efficiency, etc.Leaf area, water and nutrient use efficiency, etc.  Fertilize  Reduce competition Traditionally, mechanical site preparation Traditionally, mechanical site preparation Costs can be high, potential for environmental impactsCosts can be high, potential for environmental impacts Today, industry relying heavily on chemical site preparation – herbicides Today, industry relying heavily on chemical site preparation – herbicides

Literature on ‘Intensive’ Forestry Disking Bedding Subsoiling Combination Herbicides Fertilization

Mechanical Site Preparation

Soils and Sediment

Sediment and Intensive Forestry Temple Inland Alto Watersheds McBroom 2005 Blackburn et al. 1986

Sediment and Intensive Forestry International Paper Southlands Forest Summer 2006

Fertilization, Herbicides and Water Quality

Forest Fertilization  Over 1.5M acres fertilized with P or N+P in 2002  Mid-rotation fertilization (stand age 8-15 yrs) 85% of FNC stands respond to fertilization 85% of FNC stands respond to fertilization lbs N + 25 lbs P acre most common lbs N + 25 lbs P acre most common Costs - $100 per acre Costs - $100 per acre Fox et al. 2006

Fate of N in SE Streams  High rates of fertilization in both agriculture & forestry in the SE, however DON is the major component of Total N in streamwater.  Dissolved organic-N thought to be largely inactive biologically, with little impact on aquatic systems

Forest Fertilization and Water Quality  NCASI Technical Bulletin #782 National review of forest fertilization studies National review of forest fertilization studies  Forest fertilization commonly leads to moderate increases in streamwater nutrient concentrations  Greatest nutrient increases come from: Direct application to streams Direct application to streams Ammonium nitrate forms of fertilizer Ammonium nitrate forms of fertilizer Excessive application rates Excessive application rates Repeated applications Repeated applications  Even in these situations, impacts are too small to degrade water quality

Carteret 7 Study  Loblolly pine (15-yr-old stand) 170 kg N + 28 kg P ha -1, as urea and DAP 170 kg N + 28 kg P ha -1, as urea and DAP Ground application Ground application Nutrient concentrations Nutrient concentrations NO 3 increased from 0.6 mg/L to 1.2 mg/LNO 3 increased from 0.6 mg/L to 1.2 mg/L NH 4 increased from 0.06 mg/L to 3.8 mg/LNH 4 increased from 0.06 mg/L to 3.8 mg/L P increased from 0.04 mg/L to 0.18 mg/LP increased from 0.04 mg/L to 0.18 mg/L Returned to baseline levels ~ 3wks Returned to baseline levels ~ 3wks Important to note that streams were avoided Important to note that streams were avoided Campbell 1989

Carteret 7 Study II  Loblolly pine (6-yr-old stand) Poorly drained loam soil Poorly drained loam soil 215 kg N + 35 kg P ha -1, as urea and DAP 215 kg N + 35 kg P ha -1, as urea and DAP Aerial application Aerial application Peak nutrient concentrations ~ 1 wk Peak nutrient concentrations ~ 1 wk NO 3 – 0.12 mg/LNO 3 – 0.12 mg/L NH 4 – 3.7 mg/LNH 4 – 3.7 mg/L Total P – 1.11 mg/LTotal P – 1.11 mg/L Baseline levels returned after 12wks Baseline levels returned after 12wks Direct input of fertilizer to streams accounted for 70-80% of nutrients exported Direct input of fertilizer to streams accounted for 70-80% of nutrients exported Herman and White 1996

Why Interest in Herbicides?   Herbicide applications reduce competition for: Light Water Nutrients   Increased productivity   Reduce site preparation costs   Questions on the fate of herbicides: Water quality Aquatics Wildlife Haywood et al. 2003

Common Commercial Forestry Herbicides  Glyphosate - Accord  Hexazinone - Velpar  Imazapyr - Arsenal, Chopper  Metsulfuron - Escort  Sulfometuron - Oust  Triclopyr - Garlon

Herbicide Response Temple Inland Alto Watersheds NCASI 2006

Herbicide Response International Paper Southlands Forest NCASI 2006

Herbicide Toxicity  Maximum measured concentrations Hexazinone - 30 ppb Hexazinone - 30 ppb Imazapyr - 40 ppb Imazapyr - 40 ppb  Detection levels below 1 ppb generally less than 150 days after application  Imazapyr and Hexazinone Published LC 50 values = 10 6 ppb Published LC 50 values = 10 6 ppb NCASI 2006a, NCASI 2006b

Watershed Studies in the South  Consistent trends observed Small, temporary changes in stream hydrology Small, temporary changes in stream hydrology Small, temporary changes in stream water chemistry following fertilization Small, temporary changes in stream water chemistry following fertilization Extremely low levels of herbicide residues Extremely low levels of herbicide residues  Disturbance events can be more significant than ‘intensive’ management prescriptions using fertilization and herbicides Tropical and summer storm events significant Tropical and summer storm events significant

Harvesting

Forestry BMP Efficacy in the SE Figure from M. Miwa, International Paper

BMPs Simplified to Five Principles  Minimize bare ground and soil compaction  Separate bare ground from surface waters  Separate fertilizer and pesticide application from surface waters  Provide a forested buffer around streams  Engineer stable road surfaces and stream crossings Jackson and Olzewski 2005

Roads and Stream Crossings  Harvesting does not result in declines in environmental quality Soils and Water Soils and Water  Roads & Stream Crossings are the greatest threats to water quality when… BMPs not utilized BMPs not utilized BMPs installed improperly BMPs installed improperly  State BMP compliance reports point this out

Thank You…