Supplementary Material 1: Pseudocode for the tree management model

Caplat P, Hui C, Maxwell BM and Peltzer DA

SETUP-1

initialise parameter settings

draw values from random-distributions as described in Table 1.

import fractal map

create 16 management units

initialise cells:

set c-surv = Sseedl

set c-est = 1

set c-f = f

if Htarget="Pest" set c-est= c-est/Hs

if Htarget="survival" set c-surv=c-survl/Hs

if Htarget="fecundity" set c-f=c-f/Hs

place 8 plantations randomly:

create a cohort of age 50 and size between 1 and K

measure number of adults and stems

set cohort fecundity = f

REPEAT FOR ALLOCATION = habitat, density, equal, and SELECTION= distance, habitat, density

SETUP-2

initialise managers:

attribute each management unit to one manager

if trees in the management unit active manager

calculate pro-inv: proportion of total invaded area in each unit

calculate pro-hab: proportion of total suitable area in each unit

move managers to centroid of invasion

allocate effort to each management unit where management is active:

if allocation strategy is habitat set m-eff total effort * pro-hab

if allocation strategy is density m-eff total effort * pro-inv

if allocation strategy is equal m-eff total effort / number of active managers

RUN

cohorts grow

set age age + 1

if age > Arep cohort is adult

if age <=5 survive with probability c-s

cells update density

repeat c-f * cohort-size * Pest

create seed

if random number < Pldd draw dispersal distance from U(0,20) else dispersal distance from U(20, DDmax)

draw direction between 0 and 360

move seed to destination (distance, direction)

if random number < c-est of cell at destination

add 1 to cohort of age 0

if time-step / Uf equal to round(time-step / Uf)

if trees in the management unit active manager

calculate pro-inv: proportion of total invaded area in each unit

calculate pro-hab: proportion of total suitable area in each unit

move managers to centroid of invasion

allocate effort to each management unit where management is active:

if allocation strategy is habitat set m-eff total effort * pro-hab

if allocation strategy is density m-eff total effort * pro-inv

if allocation strategy is equal m-eff total effort / number of active managers

manage each management unit

set stands cells with trees

if selection = distance set target = stands at maximum distance from centroid of invasion

if selection = habitat set target = stands with suitable habitat

if selection = density set target = stands with highest density

kill all trees in m-eff stands randomly-drawn from target

if size(target)<m-eff kill all trees in (m-eff – size (target)) stands randomly-drawn from all stands