Bark Beetle Host Basal Area Hazard Rating

Classify measured host basal-area share under a caller dominance policy while retaining pooled inventory; host availability alone does not establish beetle outbreak probability or tree hazard.

Description

Host basal-area share represents availability of host trees.

Host basal-area share represents availability of host trees. A caller's dominance bands describe that inventory without establishing outbreak probability.^[1]

Classify measured host basal-area share under a caller dominance policy while retaining pooled inventory; host availability alone does not establish beetle outbreak probability or tree hazard.

When to use Bark Beetle Host Basal Area Hazard Rating

Use this tool to classify measured host basal-area share under a caller dominance policy while retaining pooled inventory; host availability alone does not establish beetle outbreak probability or tree hazard.

Gather the tree inventory, plot measurements or model parameters. Check diameter, area, time and moisture conventions; keep paired observations aligned.

How to use Bark Beetle Host Basal Area Hazard Rating and understand its results

Gather the tree inventory, plot measurements or model parameters. Check diameter, area, time and moisture conventions; keep paired observations aligned.
Enter hostBasalAreasM2, otherBasalAreasM2, callerHostFractionLowerEdges using the field table and calculation rules, then run the tool.
Read hostBasalAreaFractions, callerHostDominanceClassCodes, pooledHostBasalAreaFraction. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
hostBasalAreasM2	Host basal areas m2	list of number	Required
otherBasalAreasM2	Other basal areas m2	list of number	Required
callerHostFractionLowerEdges	Caller host fraction lower edges	list of number	Required

Pair nonnegative host/other m² with positive local totals. Provide 2–128 increasing lower edges in [0,1] beginning at zero. Return local shares, zero-based inclusive-lower band codes and the pooled inventory share.

Paired lists must be nonempty and have equal lengths. Each sequence checked for increasing order must contain at least two strictly increasing values.

host share=host basal area/(host+other basal area)

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
hostBasalAreaFractions	Host basal area fractions	list of number
callerHostDominanceClassCodes	Caller host dominance class codes	list of number
pooledHostBasalAreaFraction	Pooled host basal area fraction	number

json

{
  "input": {
    "hostBasalAreasM2": [
      6,
      4
    ],
    "otherBasalAreasM2": [
      4,
      16
    ],
    "callerHostFractionLowerEdges": [
      0,
      0.3,
      0.7
    ]
  },
  "output": {
    "hostBasalAreaFractions": [
      0.6,
      0.2
    ],
    "callerHostDominanceClassCodes": [
      1,
      0
    ],
    "pooledHostBasalAreaFraction": 0.3333333333333333
  }
}

Limitations and assumptions

Host identity and bands are supplied. Beetle outbreak and individual tree hazard are not predicted.

Numeric inputs and returned numeric values must be finite; an unrepresentable returned value produces an error. Numeric lists are limited to 100,000 entries; the rules above may require smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use Gypsy Moth Egg-Mass Defoliation Threshold Checker: Screen observed egg-mass surveys with differential detection against caller density threshold; no embedded outbreak/defoliation model, species attribution or treatment recommendation. For a complementary task, use Species Importance Value: Calculate the three-component 0–300 importance-value convention from measured stems, basal area and plot occurrences; not percentage dominance alone or ecological importance certification.

References

Bark Beetle Host Basal Area Hazard Rating — tool.io

Similar or alternative tools

Gypsy Moth Egg-Mass Defoliation Threshold Checker
Screen observed egg-mass surveys with differential detection against caller density threshold; no embedded outbreak/defoliation model, species attribution or treatment recommendation.
Species Importance Value
Calculate the three-component 0–300 importance-value convention from measured stems, basal area and plot occurrences; not percentage dominance alone or ecological importance certification.