Master Craftsman Forestry cheat sheet

Silvicultural systems divide into even-aged (clearcut, seed-tree, shelterwood) and uneven-aged (single-tree, group selection); the regeneration method must match the species' shade tolerance and seed-dispersal distance.

Shade tolerance ranking examples: very tolerant - hemlock, sugar maple, beech; intermediate - white pine, yellow-poplar; intolerant - aspen, jack pine, Douglas-fir (interior).

Shelterwood sequence: preparatory cut, seed cut (residual basal area typically 30-60% of full stocking for tolerant regeneration), removal cut after seedling establishment.

Seed-tree method retains 5-15 evenly spaced dominant trees per acre; suitable only for light-seeded, wind-dispersed, intolerant species such as pine and aspen.

Stocking guides relate trees per acre and quadratic mean diameter to a reference basal area; relative density = stand basal area / maximum basal area for that QMD, with 100% = B-line and 60% commonly the C-line for full stocking.

Stand development stages: stand initiation, stem exclusion (self-thinning, Reineke's SDI slope near -1.6), understory reinitiation, complex/old-growth stage.

Site index is height of dominant/codominant trees at a reference age (often 50 or 100 years); use it to rank site productivity within a species and region, never across species directly.

Disturbance regimes: fire-adapted species (longleaf pine, ponderosa pine) need frequent low-severity fire; clearcutting mimics stand-replacing disturbance for intolerant species but alters coarse woody debris and structural retention.

DBH is measured at 4.5 ft (1.37 m) above ground on the uphill side; if a fork, swell, or buttress occurs at that height, measure at the nearest acceptable point and note it.

Basal area per tree (ft²) = 0.005454 × DBH²; basal area per acre = 0.005454 × ΣDBH². Metric: BA (m²) = 0.00007854 × DBH(cm)².

Tree volume tables use Girard form class (ratio of inside-bark diameter at 17 ft to DBH) or a taper equation; Scribner log rule is the common board-foot scale in the eastern US, Doyle is conservative, International 1/4-inch is most accurate.

Fixed-radius plot: trees per acre = (number of trees × 43,560) / (plot area in ft²). Variable-radius (prism) plot: trees per acre per tallied tree = BAF / (0.005454 × DBH²).

Sampling error: standard error of the mean = s / √n; the 95% confidence half-width = t × SE. To halve the confidence interval, quadruple sample size.

Stocking and SDI: Reineke SDI = trees per acre × (QMD/10)^1.605 for many species; relative density = SDI / maximum SDI.

Height measurement with a clinometer: height = horizontal distance × (tan top angle ± tan bottom angle); add eye height when the base is below eye level.

Cruise design choices: systematic grid for spatial coverage, stratified random for known variability, double sampling with photo or LiDAR for efficiency; check for boundary slopover with the mirage or limiting-distance method.

Ground-based systems (skidder, forwarder) suit slopes under about 30-35% depending on soil and machine; cable systems (yarder, skyline) handle steeper terrain; helicopter is reserved for high-value or environmentally sensitive sites.

Skyline payload is limited by the skyline's safe working load and deflection; check tension, sag, and clearance before every turn, and never exceed the manufacturer's line rating.

Soil compaction risk rises with moisture content above field capacity; limit traffic to designated skid trails covering roughly 10-15% of the harvest area on sensitive soils.

Best management practices (BMPs) for stream crossings: permanent bridges preferred; if culverts are used, size for the 25-year flow plus debris, and remove temporary crossings before the wet season.

Felling direction, hinge wood thickness (about 10% of DBH), and escape route at 45 degrees back from the stump are core chainsaw safety rules; bore-cut for leaners and head-lean trees.

Production cost per unit = (machine rate including ownership and operating cost) / (productive hours × utilization). Utilization below 60% usually indicates poor layout or decking logistics.

Landing and deck layout: minimize skid distance (target under 800-1,000 ft for ground skidding), locate on stable, well-drained ground away from streams.

Biomass harvesting removes tops and limbs, increasing nutrient export; retain slash on nutrient-poor sites and follow state woody-biomass guidelines.

Bark beetles (mountain pine beetle, southern pine beetle, spruce beetle): mass-attack via aggregation pheromones; signs include pitch tubes, frass, and J-shaped galleries under bark. Suppression uses pheromone anti-aggregants (verbenone) and rapid salvage.

Defoliators (spruce budworm, gypsy moth, tussock moth): repeated defoliation reduces growth; outbreak collapse often follows natural enemies and starvation. Bt (Bacillus thuringiensis) is a targeted biological control.

Root diseases: Annosus root rot (Heterobasidion) spreads via spores on fresh stumps - treat stumps with borax; Armillaria and laminated root rot spread via root contacts.

White pine blister rust (Cronartium ribicola) requires an alternate host (Ribes); management includes pruning, resistant stock, and Ribes eradication near plantations.

Oak wilt (Bretziella fagacearum) spreads by root grafts and sap beetles; do not prune oaks during the spring vector-active period.

Fire behavior triangle: fuel, weather, topography. Rate of spread increases with wind, slope, and fine-fuel continuity; the 30-30-30 rule flags danger (temp >30°C, RH <30%, wind >30 km/h).

Prescribed fire: plan for a test fire, hold a written burn plan with weather windows, smoke management, and contingency resources; mop-up is required before declaring containment.

Integrated pest management sequence: identify, monitor (traps, aerial survey), set economic threshold, then cultural, biological, and chemical controls in that order.

Even-aged regulation methods: area control (equal area cut each period), volume control (equal volume), and combined; rotation age is set by culmination of mean annual increment (MAI) or a financial criterion.

Optimal financial rotation: harvest when marginal value growth equals the alternative rate of return - the Faustmann criterion maximizes soil expectation value (SEV).

Present net worth = Σ (revenues − costs)/(1+i)^t. SEV = NPV / [(1 − (1+i)^(−n))], where n is rotation length.

MAI = total volume / age; PAI (periodic annual increment) = volume change over period / years. Harvest when PAI falls below MAI for a biological rotation.

Stumpage price = delivered log price − harvest and haul cost − profit margin and risk allowance. Timber sale appraisal uses these residual values by product class (sawtimber, pulpwood).

Discount rate choice dominates long-horizon analysis; real (inflation-adjusted) rates should be paired with real prices, nominal with nominal - never mix.

Forest management plan core elements: ownership objectives, resource inventory, stand prescriptions, harvest schedule, road and BMP plan, monitoring, and maps with legal description.

Carbon and ecosystem-service markets add revenue streams; verify additionality, permanence, and registry standards before counting credits.

Road design uses a design vehicle's turning radius, stopping sight distance, and superelevation; minimum curve radius increases with design speed.

Stopping sight distance = perception-reaction distance + braking distance; typical forest road design speed is 15-25 mph.

Cross-drain spacing is set by slope and soil erodibility - closer spacing on steep, fine-textured soils to prevent ditch and road-surface erosion.

Culvert sizing: use peak flow from a design storm (often the 25-year event for forest roads) and apply inlet/outlet control hydraulics; keep the culvert invert at or slightly below the streambed.

Road prism: crown or inslope/outslope for drainage, cut-and-fill balanced where possible; sidecast fill on steep slopes risks mass wasting.

Stream crossing structures: bridges for larger streams, arch culverts or bottomless culverts for fish passage; design for bankfull width and flood capacity.

Grade limits: sustained grades above about 10-12% raise erosion and maintenance costs; short pitches may exceed this with paved or rocked surfacing.

Road decommissioning: remove culverts, recontour, outslope, and revegetate; prioritize crossings and unstable fills first.

Habitat elements: food, cover, water, space, and arrangement. Manage for the limiting factor first - identify it via inventory, not assumption.

Early successional species (grouse, woodcock, golden-winged warbler) need young forest patches; mature-forest species (fisher, pileated woodpecker) need large trees, snags, and coarse woody debris.

Snag and down-wood targets: retain 3-6 snags per acre (varying DBH) and a mix of decay classes to support cavity nesters and invertebrates.

Riparian buffers: width and shading control stream temperature; retain 50-100 ft buffers on fish-bearing streams, wider on steep or erodible banks.

Large woody debris creates pools and cover for salmonids; retain key pieces (≥ 12 in diameter, ≥ 20 ft long) in streams and recruit from the buffer.

Edge effects: increased predation and nest parasitism along hard edges; use soft edges and minimize fragmentation of interior forest blocks.

Fisheries metrics: pool-to-riffle ratio, bank stability, substrate embeddedness, and canopy cover are common habitat-quality indicators.

Stream crossing structures should mimic natural channel conditions (bankfull width, substrate, slope) to maintain fish passage at all life stages.

Sediment is the leading pollutant from forest operations; sources are roads, skid trails, crossings, and failed fills. Control at the source, then convey, then settle.

Streamside management zones (SMZs) filter sediment and shade streams; exclude heavy equipment and keep partial canopy on the SMZ.

Best management practices are largely voluntary but enforceable through state forestry water-quality laws and the Clean Water Act (TMDL, 404 permits for fill).

Peak flow estimation: use regional regression equations or the rational method (Q = CiA) for small drainages; larger basins need gage or regional regression data.

Watershed hydrology: forest harvest can increase water yield for years after cutting; road networks alter flow paths and can raise peak flows.

Temperature: shading and groundwater input control stream temperature; removing riparian canopy can push streams above thermal tolerances for coldwater fish.

Monitoring design: paired-watershed studies establish treatment effects; grab samples must capture storm events to be meaningful for sediment.

Erosion control: water bars, broad-based dips, silt fence, and check dams reduce transport; vegetate disturbed ground before the wet season.

Major federal statutes: National Environmental Policy Act (EIS/EA), Endangered Species Act (Section 7 consultation, Section 9 take prohibition), Clean Water Act (Section 404 dredge and fill), National Forest Management Act (forest plans).

Endangered Species Act listing categories: endangered, threatened, candidate; critical habitat designation follows listing and affects federal actions.

State forestry practice laws (e.g., forest practices acts) set notification, buffer, and reforestation requirements; penalties can include stop-work orders and civil penalties.

Timber trespass: unauthorized cutting of another's timber; damages may be treble in many states for willful trespass. Verify property lines before felling.

Boundary law: monuments and original surveys generally control over area or deed calls; adverse possession and prescriptive easements vary by state.

Professional ethics: disclose conflicts of interest, avoid misrepresentation of inventory or appraisal data, maintain confidentiality, and follow certification standards (e.g., SAF code of ethics).

Contract essentials: parties, legal description, volume and product specifications, payment terms, duration, insurance, and BMP compliance clauses.

Certification schemes (FSC, SFI) impose third-party audited standards that can exceed legal minimums; know which applies to the sale.

OSHA logging standards (29 CFR 1910.266) require PPE: head protection, eye and hearing protection, cut-resistant leg protection, and foot protection for chainsaw work.

Chainsaw kickback control: chain brake, low-kickback chain, correct bar length, and two-handed grip; never cut above shoulder height.

Felling: clear the escape route, use a hinge of about 10% of DBH, and retreat at 45 degrees; do not cut alone - maintain a buddy or check-in system for remote work.

First aid: control bleeding, treat for shock, and have a written emergency response plan with coordinates and nearest hospital for remote sites.

Machine safety: ROPS/FOPS cabs, seat belts, pre-shift walkaround inspection, and lockout procedures for maintenance.

Heat and cold stress: hydration and work-rest cycles in heat; layered clothing and frostbite checks in cold; lightning - leave ridges and open ground when thunder is heard.

Professional practice: keep field notes, calibration records, and chain-of-custody for samples; report uncertainty honestly in cruises and appraisals.

Continuing education and licensing: many states require forester registration or licensing; know your scope of practice and when to refer to an engineer or attorney.

Silvicultural systems divide into even-aged (clearcut, seed-tree, shelterwood) and uneven-aged (single-tree, group selection); the regeneration method must match the species' shade tolerance and seed-dispersal distance.

Shade tolerance ranking examples: very tolerant - hemlock, sugar maple, beech; intermediate - white pine, yellow-poplar; intolerant - aspen, jack pine, Douglas-fir (interior).

Shelterwood sequence: preparatory cut, seed cut (residual basal area typically 30-60% of full stocking for tolerant regeneration), removal cut after seedling establishment.

Seed-tree method retains 5-15 evenly spaced dominant trees per acre; suitable only for light-seeded, wind-dispersed, intolerant species such as pine and aspen.

Stocking guides relate trees per acre and quadratic mean diameter to a reference basal area; relative density = stand basal area / maximum basal area for that QMD, with 100% = B-line and 60% commonly the C-line for full stocking.

Stand development stages: stand initiation, stem exclusion (self-thinning, Reineke's SDI slope near -1.6), understory reinitiation, complex/old-growth stage.

Site index is height of dominant/codominant trees at a reference age (often 50 or 100 years); use it to rank site productivity within a species and region, never across species directly.

Disturbance regimes: fire-adapted species (longleaf pine, ponderosa pine) need frequent low-severity fire; clearcutting mimics stand-replacing disturbance for intolerant species but alters coarse woody debris and structural retention.

DBH is measured at 4.5 ft (1.37 m) above ground on the uphill side; if a fork, swell, or buttress occurs at that height, measure at the nearest acceptable point and note it.

Basal area per tree (ft²) = 0.005454 × DBH²; basal area per acre = 0.005454 × ΣDBH². Metric: BA (m²) = 0.00007854 × DBH(cm)².

Tree volume tables use Girard form class (ratio of inside-bark diameter at 17 ft to DBH) or a taper equation; Scribner log rule is the common board-foot scale in the eastern US, Doyle is conservative, International 1/4-inch is most accurate.

Fixed-radius plot: trees per acre = (number of trees × 43,560) / (plot area in ft²). Variable-radius (prism) plot: trees per acre per tallied tree = BAF / (0.005454 × DBH²).

Sampling error: standard error of the mean = s / √n; the 95% confidence half-width = t × SE. To halve the confidence interval, quadruple sample size.

Stocking and SDI: Reineke SDI = trees per acre × (QMD/10)^1.605 for many species; relative density = SDI / maximum SDI.

Height measurement with a clinometer: height = horizontal distance × (tan top angle ± tan bottom angle); add eye height when the base is below eye level.

Cruise design choices: systematic grid for spatial coverage, stratified random for known variability, double sampling with photo or LiDAR for efficiency; check for boundary slopover with the mirage or limiting-distance method.

Ground-based systems (skidder, forwarder) suit slopes under about 30-35% depending on soil and machine; cable systems (yarder, skyline) handle steeper terrain; helicopter is reserved for high-value or environmentally sensitive sites.

Skyline payload is limited by the skyline's safe working load and deflection; check tension, sag, and clearance before every turn, and never exceed the manufacturer's line rating.

Soil compaction risk rises with moisture content above field capacity; limit traffic to designated skid trails covering roughly 10-15% of the harvest area on sensitive soils.

Best management practices (BMPs) for stream crossings: permanent bridges preferred; if culverts are used, size for the 25-year flow plus debris, and remove temporary crossings before the wet season.

Felling direction, hinge wood thickness (about 10% of DBH), and escape route at 45 degrees back from the stump are core chainsaw safety rules; bore-cut for leaners and head-lean trees.

Production cost per unit = (machine rate including ownership and operating cost) / (productive hours × utilization). Utilization below 60% usually indicates poor layout or decking logistics.

Landing and deck layout: minimize skid distance (target under 800-1,000 ft for ground skidding), locate on stable, well-drained ground away from streams.

Biomass harvesting removes tops and limbs, increasing nutrient export; retain slash on nutrient-poor sites and follow state woody-biomass guidelines.

Bark beetles (mountain pine beetle, southern pine beetle, spruce beetle): mass-attack via aggregation pheromones; signs include pitch tubes, frass, and J-shaped galleries under bark. Suppression uses pheromone anti-aggregants (verbenone) and rapid salvage.

Defoliators (spruce budworm, gypsy moth, tussock moth): repeated defoliation reduces growth; outbreak collapse often follows natural enemies and starvation. Bt (Bacillus thuringiensis) is a targeted biological control.

Root diseases: Annosus root rot (Heterobasidion) spreads via spores on fresh stumps - treat stumps with borax; Armillaria and laminated root rot spread via root contacts.

White pine blister rust (Cronartium ribicola) requires an alternate host (Ribes); management includes pruning, resistant stock, and Ribes eradication near plantations.

Oak wilt (Bretziella fagacearum) spreads by root grafts and sap beetles; do not prune oaks during the spring vector-active period.

Fire behavior triangle: fuel, weather, topography. Rate of spread increases with wind, slope, and fine-fuel continuity; the 30-30-30 rule flags danger (temp >30°C, RH <30%, wind >30 km/h).

Prescribed fire: plan for a test fire, hold a written burn plan with weather windows, smoke management, and contingency resources; mop-up is required before declaring containment.

Integrated pest management sequence: identify, monitor (traps, aerial survey), set economic threshold, then cultural, biological, and chemical controls in that order.

Even-aged regulation methods: area control (equal area cut each period), volume control (equal volume), and combined; rotation age is set by culmination of mean annual increment (MAI) or a financial criterion.

Optimal financial rotation: harvest when marginal value growth equals the alternative rate of return - the Faustmann criterion maximizes soil expectation value (SEV).

Present net worth = Σ (revenues − costs)/(1+i)^t. SEV = NPV / [(1 − (1+i)^(−n))], where n is rotation length.

MAI = total volume / age; PAI (periodic annual increment) = volume change over period / years. Harvest when PAI falls below MAI for a biological rotation.

Stumpage price = delivered log price − harvest and haul cost − profit margin and risk allowance. Timber sale appraisal uses these residual values by product class (sawtimber, pulpwood).

Discount rate choice dominates long-horizon analysis; real (inflation-adjusted) rates should be paired with real prices, nominal with nominal - never mix.

Forest management plan core elements: ownership objectives, resource inventory, stand prescriptions, harvest schedule, road and BMP plan, monitoring, and maps with legal description.

Carbon and ecosystem-service markets add revenue streams; verify additionality, permanence, and registry standards before counting credits.

Road design uses a design vehicle's turning radius, stopping sight distance, and superelevation; minimum curve radius increases with design speed.

Stopping sight distance = perception-reaction distance + braking distance; typical forest road design speed is 15-25 mph.

Cross-drain spacing is set by slope and soil erodibility - closer spacing on steep, fine-textured soils to prevent ditch and road-surface erosion.

Culvert sizing: use peak flow from a design storm (often the 25-year event for forest roads) and apply inlet/outlet control hydraulics; keep the culvert invert at or slightly below the streambed.

Road prism: crown or inslope/outslope for drainage, cut-and-fill balanced where possible; sidecast fill on steep slopes risks mass wasting.

Stream crossing structures: bridges for larger streams, arch culverts or bottomless culverts for fish passage; design for bankfull width and flood capacity.

Grade limits: sustained grades above about 10-12% raise erosion and maintenance costs; short pitches may exceed this with paved or rocked surfacing.

Road decommissioning: remove culverts, recontour, outslope, and revegetate; prioritize crossings and unstable fills first.

Habitat elements: food, cover, water, space, and arrangement. Manage for the limiting factor first - identify it via inventory, not assumption.

Early successional species (grouse, woodcock, golden-winged warbler) need young forest patches; mature-forest species (fisher, pileated woodpecker) need large trees, snags, and coarse woody debris.

Snag and down-wood targets: retain 3-6 snags per acre (varying DBH) and a mix of decay classes to support cavity nesters and invertebrates.

Riparian buffers: width and shading control stream temperature; retain 50-100 ft buffers on fish-bearing streams, wider on steep or erodible banks.

Large woody debris creates pools and cover for salmonids; retain key pieces (≥ 12 in diameter, ≥ 20 ft long) in streams and recruit from the buffer.

Edge effects: increased predation and nest parasitism along hard edges; use soft edges and minimize fragmentation of interior forest blocks.

Fisheries metrics: pool-to-riffle ratio, bank stability, substrate embeddedness, and canopy cover are common habitat-quality indicators.

Stream crossing structures should mimic natural channel conditions (bankfull width, substrate, slope) to maintain fish passage at all life stages.

Sediment is the leading pollutant from forest operations; sources are roads, skid trails, crossings, and failed fills. Control at the source, then convey, then settle.

Streamside management zones (SMZs) filter sediment and shade streams; exclude heavy equipment and keep partial canopy on the SMZ.

Best management practices are largely voluntary but enforceable through state forestry water-quality laws and the Clean Water Act (TMDL, 404 permits for fill).

Peak flow estimation: use regional regression equations or the rational method (Q = CiA) for small drainages; larger basins need gage or regional regression data.

Watershed hydrology: forest harvest can increase water yield for years after cutting; road networks alter flow paths and can raise peak flows.

Temperature: shading and groundwater input control stream temperature; removing riparian canopy can push streams above thermal tolerances for coldwater fish.

Monitoring design: paired-watershed studies establish treatment effects; grab samples must capture storm events to be meaningful for sediment.

Erosion control: water bars, broad-based dips, silt fence, and check dams reduce transport; vegetate disturbed ground before the wet season.

Major federal statutes: National Environmental Policy Act (EIS/EA), Endangered Species Act (Section 7 consultation, Section 9 take prohibition), Clean Water Act (Section 404 dredge and fill), National Forest Management Act (forest plans).

Endangered Species Act listing categories: endangered, threatened, candidate; critical habitat designation follows listing and affects federal actions.

State forestry practice laws (e.g., forest practices acts) set notification, buffer, and reforestation requirements; penalties can include stop-work orders and civil penalties.

Timber trespass: unauthorized cutting of another's timber; damages may be treble in many states for willful trespass. Verify property lines before felling.

Boundary law: monuments and original surveys generally control over area or deed calls; adverse possession and prescriptive easements vary by state.

Professional ethics: disclose conflicts of interest, avoid misrepresentation of inventory or appraisal data, maintain confidentiality, and follow certification standards (e.g., SAF code of ethics).

Contract essentials: parties, legal description, volume and product specifications, payment terms, duration, insurance, and BMP compliance clauses.

Certification schemes (FSC, SFI) impose third-party audited standards that can exceed legal minimums; know which applies to the sale.

OSHA logging standards (29 CFR 1910.266) require PPE: head protection, eye and hearing protection, cut-resistant leg protection, and foot protection for chainsaw work.

Chainsaw kickback control: chain brake, low-kickback chain, correct bar length, and two-handed grip; never cut above shoulder height.

Felling: clear the escape route, use a hinge of about 10% of DBH, and retreat at 45 degrees; do not cut alone - maintain a buddy or check-in system for remote work.

First aid: control bleeding, treat for shock, and have a written emergency response plan with coordinates and nearest hospital for remote sites.

Machine safety: ROPS/FOPS cabs, seat belts, pre-shift walkaround inspection, and lockout procedures for maintenance.

Heat and cold stress: hydration and work-rest cycles in heat; layered clothing and frostbite checks in cold; lightning - leave ridges and open ground when thunder is heard.

Professional practice: keep field notes, calibration records, and chain-of-custody for samples; report uncertainty honestly in cruises and appraisals.

Continuing education and licensing: many states require forester registration or licensing; know your scope of practice and when to refer to an engineer or attorney.