The document discusses how the O'ahu Invasive Species Committee (OISC) uses ArcGIS to prioritize control of invasive plant species on O'ahu. OISC works to prevent, eradicate, and stop the spread of invasive species. It evaluates species recommended by the state using risk assessments and delimits their locations using surveys within 200m and 600m buffers in ArcGIS. This allows OISC to track survey progress, check for barriers to control, and summarize land ownership to obtain access and focus eradication efforts. Using ArcGIS throughout the process helps prevent new invasive species from establishing like miconia and supports early detection and control.

1. Using ArcGIS to Prioritize
Invasive Plant Control
Jean Fujikawa (Operations Planner / Analyst)
Hawai‘i Pacific GIS Conference
March 5, 2012

2. Agenda
• OISC overview
– who we are
– our target species
– miconia model example
• Evaluating potential species for control
using ArcGIS
– OED survey and evaluation
– OISC delimiting surveys

3. The O‘ahu Invasive Species Committee (OISC) is a voluntary
partnership of private, governmental and non-profit organizations
and individuals united to prevent new invasive species infestations
on the island of O‘ahu, to eradicate incipient invasive species, and
to stop established invasive species from spreading.

4. Some of OISC’s target species
Miconia Coqui Frog Himalayan Beardgrass
Miconia calvescens Eleutherodactylus coqui Blackberry Andropogon glomeratus
var. pumila
Rubus discolor
Fountain Pampas Little Fire Cane
grass grass Ant tibouchina
Pennisetum setaceum Cortaderia spp. Wasmannia auropunctata Tibouchina herbacea

6. Model of miconia spreading across the
watersheds of O‘ahu in the absence of
systematic control efforts
Plants Model Affected
controlled year 10
Miconia in Tahiti Miconia model output -Mānoa

8. OED refers high threat / low
distribution species to OISC
• After road, nursery and reported species OED had list of
1797 species.
• Of the 1797 species 56 species were determined to be
– present on the island but of low distribution,
– weedy,
– could be scored by the Hawai‘i Pacific Weed Risk Assessment
(HPWRA)
• After doing full assessments of the 56 of 16 species were
chosen which high practicality of control and high
weediness scores
• OISC will delimit these 16 species and select which are
feasible to eradicate

9. Species recommended for control
by OED (first round)
• Caesalpinia crista • Parkinsonia aculeata
• Chromolaena odorata • Pennisetum villosum
• Cordia alliodora • Pereskia aculeata
• Cryptostegia • Piper aduncum
grandiflora • Rauvolfia vomitoria
• Delairea odorata • Senna artemisioides
ssp. filifolia
• Imperata cylindrica • Setaria sphacelata
• Melinis nerviglumis • Suriana maritima
• Nassella tenuissima

10. Species recommended for control
Caesalpinia Chromolaena Cordia Cryptostegia
crista odorata alliodora grandiflora
Delairea Imperata Melinis Nassella
odorata cylindrica nerviglumis tenuissima

11. Species recommended for control
Parkinsonia Pennisetum Pereskia Piper
aculeata villosum aculeata aduncum
Senna
Rauvolfia artemisioides Setaria Suriana
vomitoria ssp. filifolia sphacelata maritima

12. Distribution of
potential OISC
target species

13. General survey decision process
600m
Plants
No plants found in
found in 200m 200m
200m or
= Scour 600m good
Survey habitat
good survey
habitat =
Scour

14. General survey decision process
However, we need
permission from land
owners at each phase
of our surveys
• Hopefully they say
YES!
• If access cannot be
obtained, we document
our activity and move
the species lower on
our priority list

15. Tracking progress with ArcGIS

16. Potential species for control layout

17. Checking on buffers, terrain, roads,
trails and land ownership
•Pink: buffers, plant locations
•Orange: property boundaries
•Yellow: trails
•Blue: streams
•Gray: roads
•Brown: > 45 degree slope
•Background: 1ft imagery

18. Partial table for tracking our
delimiting survey progress
Evaluated by OED Sites 200m Survey 600m Survey Pop
buffer review buffer review extent
Caesalpinia crista 1 in prog.
Chromolaena odorata 2 in prog.
Cordia alliodora 3
Cryptostegia grandiflora 1
Delairea odorata 1 done cont. in prog. almos
Imperata cylindrica 2
Melinis nerviglumis 3 in prog.
Nassella tenuissima 3 in prog.
Parkinsonia aculeata 2 done cont. done define

19. Caesalpinia
crista
private property
Tantalus left to survey
200m
buffer
~20
plants
Tantalus

20. Pennisetum villosum
Aiea
200m buffer
Aiea
Kahala

21. Rauvolfia vomitoria and
Setaria sphacelata buffer overlap
Kāne‘ohe

22. Kalaeloa
~ 5-10 plants
per point
Cryptostegia grandiflora - 200m buffer

23. Model: Land ownership summary
• Buffer species points 200m and 600m
• Clip parcels
• Dissolve on landowner
• Result: number of different landowners, parcels per
landowner, and acres

24. Summary
• Using ArcGIS throughout the evaluation process
• Standard format for dealing with each species at
each site, however, each situation is unique
• Early detection will prevent "the next miconia"
from happening
• If you’re are ever contacted by your local ISC for
permission to survey and control on your
property, please say YES!

25. Mahalo!
• Supervisor (Rachel Neville)
• Co-workers at OISC, OED
• All our volunteers, committee members, partners
and funders for their continuing support
Jean Fujikawa - jeanyf@hawaii.edu
OISC - http://www.oahuisc.org
HWRA - http://www.botany.hawaii.edu/faculty/daehler/wra/