Table 1

Model Parameters

Parameter	Description	Value	Unit
Panel A. Objective Function Parameters
a₀	Intercept of the consumer surplus (CS) function	−2.97^a	$/day
b₀	Intercept of the user days (UD) function	9.32^a	Days/year
a₁	Linear parameter of the CS function	0.24^a	$/day/healthy tree
b₁	Linear parameter of the UD function	0.24^a	Days/healthy tree
_a₂	Quadratic parameter of CS function	−0.00017^a	Unitless
b₂	Quadratic parameter of UD function	−0.0002^a	Unitless
p	Timber prices for young and mature trees	0.11, 0.13^b	$/board feet (BF)
y_m,n,t	Timber yields for mature trees	297^c	BF/tree
c_A, c_B	Bioinvasion treatment cost	4^d	$/invaded tree
ρ	Discount factor	0.961538	Year⁻¹
T	Forward-looking years (> 5 stages)	5, 10,…, 25^e	Years
Panel B. Spatial-Dynamic Externality Parameters
α	Short distance H to E_u transition rate	0.69	Year⁻¹
N_i,j,t	Number of contiguous I_m or I_h neighbors	0,…,8	Cells
γ	Long-distance power-law parameter	3	Unitless
L₁	Average waiting time between invaded-undetectable and invaded-detectable^f	1	Years
L₂	Average waiting time between invaded-detectable to invaded-moderate^g	1	Years
L₃	Average waiting time between invaded-moderate to invaded-high^h	2	Years
τ_young	Years between juvenile and young if tree and its immediate neighbors are healthy	10	Years
τ_mature	Years between young and mature	10	Years
I×J	Grid G_A dimensions	49 × 16 = 784	Rows × columns
M×N	Grid G_B dimensions	49 × 16 = 784	(Trees per acre)

↵^a Values are from Rosenberger et al. (2013), adjusting for tree density per acre in the case of a₁ and b₁.
↵^b New Hampshire Department of Revenue Administration (2016).
↵^c Hepp et al. (2015); Smalley et al. (2016).
↵^d Ending the analysis at 25 years is consistent with landowner demographics and plans (most private forest landowners are above 65 years of age and plan to sell or transfer their land; U.S. Forest Service 2015).
↵^e Lee (2017). This assumes repeated cutting in the spring, summer, and fall to avoid regrowth.
↵^f .
↵^g .
↵^h .