ArticlePDF Available

Abstract and Figures

Red quinine tree has been recognized as a serious weed in the Galapagos National Park for three decades. During this time, a variety of control methods have been implemented, initially with poor results. In this article, we reviewed past efforts to control red quinine tree and tested a variety of herbicides and selective application methods. A mixture of picloram and metsulfuron (240 and 15 g ai/L, respectively) killed 73 to 100% of trees when applied to connecting machete cuts around the circumference of tree trunks (hack and squirt [HS]) at concentrations of 5, 10, and 20% in water, with larger trees requiring higher concentrations for best results. Although this herbicide mixture also was effective when applied using other methods, HS was the least labor intensive and costly. The control methods developed could be used to combat this weed in other locations including Hawaii and Tahiti. Nomenclature: Metsulfuron; picloram; red quinine tree, Cinchona pubescens Vahl. Additional index words: Cinchona succirubra, Galapagos National Park, Hawaii. Abbreviations: BB, basal bark; CDRS, Charles Darwin Research Station; CS, cut stump; DBH, diameter at breast height; GNP, Galapagos National Park; GS, girdle and squirt; HS, hack and squirt; H, hack only; MASL, meters above sea level; WS, wide-band hack and squirt.
Content may be subject to copyright.
Weed Technology. 2004. Volume 18:1194-1202
Symposium
The Control of a Highly Invasive Tree Cinchona pubescens in Galapagos1
CHRISTOPHER E. BUDDENHAGEN, JORGE LUIS RENTERIA, MARK GARDENER, SARAH R.
WILKINSON, MONICA SORIA, PATRICIO YANEZ, ALAN TYE, and RENE VALLE2
Abstract: Red quinine tree has been recognized as a serious weed in the Galapagos National Park
for three decades. During this time, a variety of control methods have been implemented, initially
with poor results. In this article, we reviewed past efforts to control red quinine tree and tested a
variety of herbicides and selective application methods. A mixture of picloram and metsulfuron (240
and 15 g ai/L, respectively) killed 73 to 100% of trees when applied to connecting machete cuts
around the circumference of tree trunks (hack and squirt [HS]) at concentrations of 5, 10, and 20%
in water, with larger trees requiring higher concentrations for best results. Although this herbicide
mixture also was effective when applied using other methods, HS was the least labor intensive and
costly. The control methods developed could be used to combat this weed in other locations including
Hawaii and Tahiti.
Nomenclature: Metsulfuron; picloram; red quinine tree, Cinchona pubescens Vahl.
Additional index words: Cinchona succirubra, Galapagos National Park, Hawaii.
Abbreviations: BB, basal bark; CDRS, Charles Darwin Research Station; CS, cut stump; DBH,
diameter at breast height; GNP, Galapagos National Park; GS, girdle and squirt; HS, hack and squirt;
H, hack only; MASL, meters above sea level; WS, wide-band hack and squirt.
INTRODUCTION
Approximately 550 plant species are known to have
been introduced to Galapagos by people. Of these spe-
cies, 221 have naturalized, with 100 of these becoming
established in intact native vegetation, and approximate-
ly 40 are recognized as having an effect on native veg-
etation (Charles Darwin Research Station [CDRS] Her-
barium Database 2003; S. Henderson, unpublished data).
Most weeds originate, establish, and spread from the ag-
ricultural zones in the humid highlands of the four larg-
est islands, where introductions are more frequent and
conditions more favorable than the semiarid lowlands.
Only 5% of hectarage in the Galapagos Archipelago is
zoned for agricultural and urban use, and the remaining
95% is Galapagos National Park (GNP), Galapagos, Ec-
uador. A number of introduced plant species have spread
1 Received for publication December 23, 2003, and in revised form August
28, 2004.
2 First, second, sixth, and seventh authors: Research Scientists, Charles Dar-
win Research Station, Puerto Ayora, Galapagos; third author: Research Sci-
entist, Key Centre for Tropical Wildlife Management, Charles Darwin Uni-
versity, Darwin, Northern Territory 0909, Australia; fourth author: Research
Coordinator, Department of Renewable Resources, University of Alberta, Ed-
monton, Alberta, Canada; fifth author: Tecnico Enlace, Galapagos National
Park, Puerto Ayora, Galapagos; eighth author: Park Ranger, Galapagos Na-
tional Park, Puerto Ayora, Galapagos. Corresponding author's E-mail:
chrisb@fcdarwin.org.ee.
from the agricultural zones into the GNP and appear to
have changed species composition and community struc-
ture. Among these are a number of tree species, includ-
ing guava (Psidium guajava L.), West Indian cedar (Ced-
rela odorata L.), rose apple (Syzigium jambos (L.) Al-
ston), sauco (Cestrum auriculatum (L.) Her.), and red
quinine tree; a number of woody shrubs, including lan-
tana (Lantana camara L.), hill raspberry (Rubus niveus
Thunb.), and Andean blackberry (Rubus glaucus
Benth.); and a number of vines, including yellow pas-
sionfruit (Passiflora edulis Sims.), sweet granadilla (Pas-
siflora ligularis Juss.), and fragrant Dutchman's pipe
(Aristolochia odoratissima L).
Originally from the Andean countries in the northern
part of tropical South America, red quinine tree was first
introduced in 1946 to the agricultural zone on the island
of Santa Cruz. It was planted at an altitude of 350 m
above sea level (MASL) in an area close to the current
boundary of the GNP, which was established in 1956
(Hamann 1974). It may have been introduced for its me-
dicinal qualities and as a shade tree or a live fence. Qui-
nine (Cinchona officinalis L.) is commonly used world-
wide for quinine production; red quinine tree bark in
Galapagos also contains 1 to 4% of quinine on a dry
weight basis (T. Buchler, unpublished data). Currently,
Figure 1. The area infested by red quinine tree on Santa Cruz is described using shaded areas and points. Points represent field observation of occurrences of
the tree before April 2002. Using a satellite photograph taken in March 2000, we found a color range that corresponded to two levels of infestation of red
quinine tree. Dark gray is a dense level and light gray an intermediate level.
red quinine tree is not known to occur on any other is-
land in Galapagos.
Spread of red quinine tree on Santa Cruz was rapid
because of its numerous winged wind-dispersed seeds,
capability to reproduce vegetatively, and shade tolerance
of seedlings (Jager 1999). By 1965, its presence had
been noted in the "fern-sedge zone" (Kastdalen 1982)
perhaps as far as 500 m from the agricultural zone where
it was planted, suggesting that it occupied as little as 400
ha. It occupied 4,000 ha in 1987 (Macdonald et al.
1988), 8,500 ha in 1990, and now has a range of more
than 11,000 ha (Jager 1999), covering almost 10% of the
island's area. Rentería (2002) found that 54% of the area
infested was in the agricultural zone and the rest inside
the GNP, occupying an altitudinal range of 180 to 860
MASL. Using a satellite photograph taken in March
2000, we found a color range that corresponded to two
infestation densities. The densest infestations occupied
approximately 376 ha and those of medium density
about 1,366 ha. When sampled in 2003, the heavy and
medium infestations contained 24,150 and 11,600 stems/
ha, respectively, with stems taller than 150 cm (Figure
1). The invasion of red quinine tree has resulted in com-
plete structural change to the vegetation from low open
scrub, fernbrake, and grasslands to a closed forest can-
opy of 5 to 8 m tall. On Santa Cruz, many areas have
not yet reached the maximum densities recorded or are
not yet invaded.
Red quinine tree was reported as invasive on St. He-
lena Island (Cronk and Fuller 1995) but currently is only
naturalized in a few areas of the island (Q. Cronk, per-
sonal communication). It is generally unmanaged as a
weed in Hawaii and Polynesia, where it has naturalized
in "virgin forests" (Meyer 2000). It is starting to show
its potential to become invasive on Maui with approxi-
mately 6,000 ha infested (F. Starr, personal communi-
cation). Spread in Hawaii has not been as rapid possibly
because of many of the plantations being surrounded by
tall forest (F. Starr, personal communication).
The failure to prevent the spread of red quinine tree
on Santa Cruz is the result of three main factors: not
recognizing the invasive potential early enough, ad hoc
control activities, and the lack of an effective and eco-
nomical control method. During the past 25 yr, various
manual, mechanical, and chemical control methods have
been used by the GNP and CDRS staff to control red
Figure 2. A total of 109 ha were controlled by the GNP staff before September 2003 using manual (light gray) and chemical (dark gray) methods in the area
around Media Luna; numbers indicate the year in which the work was undertaken. Details about the number of hectares controlled each year are described in
Results and Discussion.
quinine tree. During this time, trials were developed to
determine the most effective methods; however, no spe-
cific methodology was followed, and trials often con-
sisted of a treated infestation marked out for monitoring
within regular control operations.
Informal trials such as those conducted in Galapagos
are commonplace elsewhere. Managers of natural areas
more often deal with different weeds than the well-stud-
ied species of agricultural sites. In many cases, managers
undertake informal trials that produce effective methods
to control such invasive species; these methods are then
adopted for local use without ever being published. Con-
sequently, distant conservation managers often repeat
control trials that have already been undertaken else-
where.
In this article, we compiled data from a range of un-
published studies evaluating control and management of
red quinine tree on the island of Santa Cruz. We also
present the results of a series of field trials that we ini-
tiated in 1998 to determine the most effective methods
to control red quinine tree.
MATERIALS AND METHODS
We reviewed technical reports, archived notes, and
published documents that describe the historical attempts
to limit the spread of red quinine on Santa Cruz. Recent
control efforts were mapped in September 2003 using a
handheld global positioning system unit (Figure 2).
Review of Previous Unpublished Studies (1974 to
1996). We reviewed unpublished accounts of control tri-
als from a variety of sources, including personal com-
munications, notes, files, observations, and internal field
reports of the GNP and CDRS. Most trials tested a num-
ber of herbicides and applied them using one or more
methods and concentrations (Table 1). In many cases,
the information recorded during a trial was incomplete.
Herbicides tested were picloram and 2,4-D in diesel fuel
(two trials), different 2,4-D formulations (six trials), pi-
cloram and 2,4-D mixed with glyphosate (one trial), pi-
cloram and 2,4-D (four trials), glyphosate (eight trials),
unknown active ingredient herbicide (one trial), and im-
azapyr (one trial). Specific herbicide concentrations test-
ed are provided in Table 1.
Where application methods described in these unpub-
lished accounts were the same as those described for our
1998 to 2003 study, we used the same terminology and
abbreviations described in Treatment Methods. Appli-
cation methods unique to these unpublished studies in-
cluded (1) branch filling, cuts in the crux of branches
were filled with herbicide; (2) microinjection, herbicide
Table 1. Unpublished studies to determine methods of control for red quinine tree between 1974 and 1996 were reviewed from a number of sources of information; they used a variety of herbicides
containing the active ingredients grams per liter in the original unmixed product. Often, a number of concentrations (sometimes mixed with a carrier) were applied implementing one of nine methods
of application. Trials were normally undertaken by marking out plots or individual trees. Concluding observations about the effectiveness of the application methods used were noted.a
Source of
informationb Date
Andrew Schmidt 1974
and Luis Ortiz
Luong Tan Touc, 1983
Elizabeth Potts,
and C. Arturo
Luis E. Cruz 1986
Andrew Schmidt 1987
and Luis Ortiz
Mark Otto 1988
Pat Whelan January 1993
Pat Whelan May 1993
Raul Pozo June 1994
GNP Memo 1994
GNP Memo November 1996
Active
ingredientc
No data
Picloram/2,4-D
2,4-D
2,4-D
2,4-D
Picloram/2,4-D
2,4-D
Picloram/2,4-D +
2,4-D
Picloram/2,4-D
2,4-D
Picloram/2,4-D +
2,4-D
Picloram/2,4-D
Glyphosate
Picloram/2,4-D +
Glyphosate
Glyphosate
Glyphosate
Glyphosate
Glyphosate
Glyphosate
Imazapyr
Rates
g
ai/L
No data
64/240
480
No data
No data
64/240
480
64/240 + 480
64/240
480
64/240 + 480
64/240
240
64/240 + 240
No data
240
0.18 g/capsule
480
0.18 g/capsule
No data
Concentration
(mix)
20% (diesel fuel)
No data
No data
No data
No data
25% (diesel fuel)
25% (diesel fuel)
25% (diesel fuel)
5, 10, 15, and 20%
5, 10, 15, 20%
5, 10, 15, and 20%
10 and 20%
5 and 10%
No data
100 and 50%
1.5%
One capsule per 10-
cm diameter
41%
One capsule per 10-
cm diameter
No data
Methods of Area or number
application of trees
CS 1.6 ha
CS, GS, HS, BB, 180 trees
and BrF
CS, GS, HS, BB,
and BrF
CS, GS, HS, BB,
and BrF
CS, GS, HS, BB,
and BrF
CS 280 trees
CS
CS
JG 720 trees
CS and HS 75 trees
HS 166 trees
HS and FS
EZ No record
MI 68 trees
EZ 294 trees
EZ 10 trees
Effectiveness of control
All trees survived
CS gave 100% control. No differences in
control were observed between herbicides.
GS and BrF were only effective on trees
less than 10-cm DBH
44% control
34% control
31% control
Picloram and 2,4-D gave 41% mortality, and
other herbicides gave less than 10%. Mul-
tiple applications gave poor results
50% control
No data
No data
Small trees (1- to 3-cm DBH) were effec-
tively killed
HS was ineffective but FS was effective for
trees <l-cm DBH
Poor control
All trees resprouted after a year
All trees survived
No data
a Abbreviations: HS, hack and squirt; BB, basal bark; CS, cut stump; GS, girdle and squirt; BrF, branch filling; EZ, Ez-Ject® system; FS, foliar spray; JG, Jim-Gem© Tree Injector; MI, microinjection;
GNP, Galapagos National Park; DBH, diameter at breast height. For more details see Materials and Methods.
b All sources of information are unpublished internal reports or memos from Charles Darwin Research Station or GNP Service.
c Herbicides were mixed with water when diesel is not mentioned, except in the case of the Ez-Ject lance, in which case capsules of herbicide were used.
administered to the cambium using the Tree Tech® mi-
croinjection system,3 which constitutes a pressurized
plastic container containing herbicide with a narrow noz-
zle that is inserted into small holes in the cambium; (3)
Ez-Ject® system,4 a lance is used to place capsules of
herbicide under the cambium; (4) foliar spray, foliar ap-
plications of herbicide using unidentified spray system;
and (5) Jim-Gem© Tree Injector,5 measured amounts of
herbicide are injected into cuts in the bark in a similar
way to the hack and squirt (HS) method, which is de-
scribed in a subsequent section.
Latest Study (1998 to 2003). A series of three herbicide
trials to control red quinine tree were carried out between
1998 and 2003 in the GNP (Table 2). Trials were located
within Miconia and fern-sedge vegetation zones in the
highlands of Santa Cruz between 450 and 680 MASL.
The Miconia zone was historically dominated by the Ga-
lapagos endemic shrub Galapagos miconia (Miconia ro-
binsoniana Cogn.) (Melastomataceae) and exclusively
occurs on the islands of Santa Cruz and San Cristobal
(Wiggins and Porter 1971). Red quinine tree has been a
major codominant in the area since the early 1990s. The
density of red quinine trees greater than 1.5 m in height
can be as high as 40,000 stems/ha in this area. Stem
density is high because of extensive suckering from adult
trees, and the density of individual plants may actually
be similar to that found by Jager (1999), where densities
ranged from 50 to 1,100 plants/ha.
Three series of related trials were undertaken, each
using different methods for selecting trees and assigning
treatments and each started in a different year, but all
were monitored using the same criterion. Each series is
hereafter described as a "trial set" to distinguish them
from previous trials not carried out by the authors and
those described in Review of Previous Unpublished
Studies (1974 to 1996). The treatment methods sum-
marize the methods used in these three trial sets. In trial
set 1, nine adjacent plots were established, each of which
contained 45 trees, 15 in each of three diameter at breast
height (DBH) classes (<7 cm, 7 to 10 cm, and >10 cm).
One of nine treatments was randomly assigned to each
of the plots, and all trees in a plot received the same
treatment. In trial set 2, 10 plots containing 15 trees were
established, with five trees in each DBH class. Treat-
ments were assigned randomly to each plot, and all trees
in a plot received the same treatment. In trial set 3, 280
3 Florida Silvics Inc., 950 South East 215th Avenue, Morriston, FL 32668.
4 Odom Processing Engineering & Consulting Inc., P.O. Box 829, Waynes-
boro, MS 39367.
5 Forestry Suppliers Inc., P.O. Box 8397, Jackson, MS 39284-8397.
trees of DBH >10 cm were selected and seven treat-
ments were randomly assigned to individual trees so that
40 trees were treated. In all trial sets, if multiple stems
were present, all were treated. For the purpose of this
article and comparison between trial sets, diameter class
data were pooled where trees had multiple stems, e.g., a
tree with two stems with a DBH of 3 and 7 cm was
considered for our purposes equal to a tree with a single
stem of 10-cm DBH.
Treatment Methods. Specific herbicide treatments, their
use rates, and methods and date of application are indi-
cated in Table 2. The volume of herbicide mix applied
to each tree depended on the diameter of the tree and
the treatment method used. Herbicides were mixed ac-
cording to registration instructions and applied to indi-
vidual trees using a hand-pumped backpack sprayer or
handheld squirt bottles. Herbicides were applied using
water or diesel fuel (Table 2) as a carrier. The six ap-
plication methods were (1) HS, herbicide was applied
with a squirt bottle to a series of joining machete cuts,
which passed through the cambium at a downward 45°
angle around the circumference of the tree at a height of
20 to 50 cm above the ground until the herbicide filled
the cuts, (2) basal bark (BB), herbicide was applied with
a diesel-resistant backpack sprayer to the bark of trees
in a 20-cm ring that completely encircled the trunk 30
cm from the base of the tree, (3) wide-band hack and
squirt (WS), herbicide was applied with sprayer or squirt
bottle to overlapping machete cuts around the circum-
ference of the tree similar to the HS method; however,
the cuts were made in a 20- to 30-cm-wide band from
the ground upward, (4) girdle and squirt (GS), herbicide
was applied with a squirt bottle or a sprayer to a 10-cm-
wide band of stripped bark 30 to 50 cm from the ground
(girdled or ring barked) until the surface was wet, (5)
cut stump (CS), trees were cut with a chain saw about
20 cm from the surface of the ground, herbicide was
applied with a squirt bottle or a sprayer to the cut surface
of the stem until complete coverage was achieved, and
(6) hack only (H), the nontreated control consisted of
trees cut only with a ring of joined machete cuts placed
20 to 50 cm above the ground.
In 2003, we compared the amount of herbicide mix-
ture required for each of the treatment methods except
the BB method, which would require a greater volume
of herbicide than the GS method because it requires a
band twice as wide to be covered. Using 23 trees be-
tween 3.3- and 10.2-cm DBH, we determined the aver-
age amount of mixture required to treat trees of a given
Table 2. Control of red quinine tree after treatment with herbicides containing the active ingredients indicated, using five methods of application, in three sets of trials monitored for a number of DAT
on Santa Cruz between 1998 and 2003. Resprouting after treatment is indicated by a " + " in the shoots column. a
Application
methodHerbicidebDates
Trial set 1
HS
HS
BB
BB
HS
HS
HS
HS
BB
H
Picloram salt 25% (60 ai g/L)
Picloram salt 50% (120 ai g/L)
Triclopyr ester 20% (80.8 ai g/L)
Triclopyr ester 30% (121.2 ai g/L)
Triclopyr salt 50% (150 ai g/L)
Triclopyr salt 100% (300 ai g/L)
Glyphosate 50% (240 ai g/L)
Glyphosate 100% (480 ai g/L)
April 24, 1998-June 12, 1999
April 23, 1998-June 12, 1999
January 11, 1999-June 12, 1999
April 18, 1998-June 12, 1999
April 18, 1998-June 12, 1999
April 18, 1998-June 12, 1999
April 29, 1998-June 12, 1999
April 29, 1998-June 12, 1999
Diesel fuel December 18, 1998-June 12, 1999
No herbicideApril 21, 1998-June 12, 1999
Mean DBH
cm
9.11
10.61
8.84
8.50
9.76
11.41
10.12
9.02
10.04
9.50
Number of
DAT
d
414
415
152
189
420
420
348
409
176
490
Number of
treated trees
41
45
40
43
44
43
38
43
40
38
Control
%
37
71
38
77
45
74
0
2
0
0
Shoots
+
-
-
-
+
-
+
+
+
+
Trial set 2
HS
HS
HS
HS
HS
HS
HS
HS
HS
CS
Picloram + metsulfuron 5% (3.2 + 0.2 ai g/L)
Picloram + metsulfuron 10% (6.4 + 0.4 ai g/L)
Picloram + metsulfuron 20% (12.8 + 0.8 ai g/L)
Picloram + metsulfuron 5% (3.2 + 0.2 ai g/L)
Picloram + metsulfuron 10% (6.4 + 0. 4 ai g/L)
Picloram + metsulfuron 20% (12.8 + 0.8 ai g/L)
Picloram + metsulfuron 5% (3.2 + 0.2 ai g/L)
Picloram + metsulfuron 10% (6.4 + 0.4 ai g/L)
Picloram + metsulfuron 20% (12.8 + 0.8 ai g/L)
Picloram + metsulfuron 4% (2.5 + 0.16 ai g/L)
January 12, 2000-June 21, 2002
January 12, 2000-June 21, 2002
January 12, 2000-June 21, 2002
January 12, 2000-June 21, 2002
January 12, 2000-June 21, 2002
January 12, 2000-June 21, 2002
January 12, 2000-June 21, 2002
January 12, 2000-June 21, 2002
January 12, 2000-June 21, 2002
January 12, 2000-June 21, 2002
3.03
2.04
2.04
6.67
7.12
7.18
10.92
10.68
9.98
10.56
891
891
891
891
891
891
891
891
891
891
15
15
15
15
15
15
15
15
15
80
100
100
100
100
100
93
73
87
100
94
-
-
-
-
-
+
+
+
-
+
Trial set 3
GS
HS
WS
GS
HS
WS
H
Picloram + metsulfuron 10% (6.4 + 0.4 ai g/L)
Picloram + metsulfuron 10% (6.4 + 0.4 ai g/L)
Picloram + metsulfuron 20% (12.8 + 0.8 ai g/L)
Triclopyr ester 20% (120 ai g/L)
Triclopyr ester 20% (120 ai g/L)
Triclopyr ester 10% (60 ai g/L)
No herbicide
February 21, 2001-January 17, 2003
February 21, 2001-January 17, 2003
February 21, 2001-January 17, 2003
February 21, 2001-January 17, 2003
February 21, 2001-January 17, 2003
February 21, 2001-January 17, 2003
February 21, 2001-January 17, 2003
14.57
13.57
13.11
12.68
13.68
13.11
12.75
695
695
695
695
695
695
695
40
40
40
40
40
40
40
88
83
100
10
38
50
0
-
-
-
+
+
+
+
a Abbreviations: HS, hack and squirt; BB, basal bark; CS, cut stump; GS, girdle and squirt; WS, wide-band hack and squirt; H, hack only; DAT, days after treatment; DBH, diameter at breast height
(1.2 m). For more details see Materials and Methods.
b Herbicides were mixed with water except for BB application, in which case the carrier was diesel fuel.
sprouting. Glyphosate produced results little different
from the nonherbicidal H treatment (2 vs. 0% control).
In trial set 2, a mixture of picloram and metsulfuron
(240 and 15 g ai/L, respectively) was equally effective
(100% control) when applied using any of the methods
described (CS, HS, WS, or GS) and at concentrations
ranging from 4 to 20%. In all treatments, trees took at
least 6 mo to die. There was no difference between the
5, 10, and 20% concentrations of the product where
DBH was <7 cm (Table 2).
In trial set 3, application of triclopyr ester using GS,
HS, and WS was not effective on large trees in compar-
ison with the metsulfuron-picloram combination. The
WS application method, using a lower concentration but
greater volume of herbicide than HS or GS methods,
was, however, more effective. Concentrations of 20% pi-
cloram-metsulfuron product were tried with the WS
method and were more effective than the HS and GS
method using 10% concentrations.
Application Rates and Cost. The amount of herbicide
applied to each tree depended on the tree diameter and
the method used, i.e., HS (1.5 ml/cm DBH), WS (4.01
ml/cm DBH), GS (0.99 ml/cm DBH), and CS (0.7 ml/
cm DBH). The HS method used about 35% less herbi-
cide than the WS method, and there was little difference
in treatment efficacy. The only differences between these
two methods are the number of cuts and the care with
which they need to be applied. The other application
methods required less herbicide but, in general, were not
as effective for controlling red quinine tree and were
more labor intensive. For the HS method to be correctly
applied, cuts must be connecting around the trunk. If the
number of overlaps and therefore cuts can be reduced,
the volume of herbicide and cost also can be reduced.
WS and HS may allow greater absorption of the herbi-
cide because the herbicide mixture is held in the freshly
made cuts for a period during which the herbicide can
be absorbed into the cambium.
Over all trial sets, the GS and CS methods with pi-
cloram and metsulfuron (trial set 2) required the least
volume of herbicide mixture and effectively controlled
red quinine tree. The amount of work, however, required
to fell trees or remove a band of bark makes these meth-
ods costly. The CS method also damaged the surround-
ing vegetation more and may provide further opportu-
nities for reestablishment of red quinine tree and estab-
lishment of other weed species. A method that produces
less disturbance, although it may result in slower death
of standing trees, is more desirable.
The highest red quinine tree control was obtained with
a mixture of picloram and metsulfuron using the HS
method, which also required the least effort. Trees >8-
cm DBH did not die as readily, except when a 20% con-
centration was used. The GS method could be as effective
for red quinine trees >10-cm DBH, but we suggest the
HS or WS method at a concentration of 10 to 20% be
used instead because they are less labor intensive.
Although high concentrations of picloram or triclopyr
(trial set 1) were effective, the picloram and metsulfuron
combination is less costly and more readily available in
Ecuador. Prices in Ecuador for the picloram-metsulfuron
product were $37/L, whereas triclopyr (480 g ai/L) was
$24/L. In Ecuador, there are currently no sources of pi-
cloram alone, and it is always sold mixed with other
herbicides such as 2,4-D or metsulfuron. We imported
the picloram-alone product specifically for these exper-
iments. Glyphosate and diesel fuel, although readily
available, were ineffective treatments.
By 2003, the GNP staff working to control introduced
plants had successfully controlled large areas of red qui-
nine tree using the WS application method and an ap-
plication rate of 6.75% of the picloram-metsulfuron
product (C. Carvajal, personal communication). By late
September 2003, approximately 109 ha had been con-
trolled near Media Luna (Figure 2) near the highest part
of the island. Our studies show that the HS method pro-
vides the same control as WS but uses 35% less herbi-
cide; thus, one of the future management actions will be
an education and training campaign for the GNP workers
to show them how to use this method to reduce costs.
The potential of red quinine tree as an invader else-
where has been recognized but perhaps not given the
attention warranted. Red quinine tree may still be suffi-
ciently restricted in distribution on some islands in the
state of Hawaii or on St. Helena and Tahiti to eradicate
it (Meyer 2000; F. Starr, personal communication). Cer-
tainly, the feasibility of eradication should be seriously
examined because it is an easily identifiable tree that
stands out amongst other vegetation, and there is a pe-
riod of 2 to 3 yr between germination and reproduction
(J. L. Renteria, personal observation). Wherever it oc-
curs on tropical islands with humid environments, the
effective manual or chemical methods described in this
study should be used to control or eradicate this trou-
blesome species.
ACKNOWLEDGMENTS
This is a contribution (1003) to the Charles Darwin
Foundation. A number of volunteers and staff at the Bot-
any Department of Charles Darwin Research Station
have been involved in the collection of data during the
years that the latest study has been run. Their help has
been invaluable. The late Hamish Saunders helped with
the analysis of the satellite image in Figure 1. The GNP
Introduced Plants group currently managed by Carlos
Carvajal has done an amazing job in recent years con-
trolling large areas of red quinine tree as described in
Figure 2. Thanks to the GNP for access to archives for
the review of historical control efforts. Funding provided
by the United Nations Foundation, Monsanto, and the
Global Environment Facility invasive species project
through UNDP-ECU/00/G31 is gratefully acknowledged.
LITERATURE CITED
Cronk, Q.C.B. and J. L. Fuller. 1995. Plant Invaders. The Threat to Natural
Ecosystems. London: Chapman and Hall. 147 p.
Hamann, O. 1974. Contributions to the flora and vegetation of the Galapagos
Islands. 5 new floristic records. Bot. Not. 127:309-316.
Jager, H. 1999. Impact of the Introduced Tree Cinchona pubescens Vahl. On
the Native Flora of the Highlands of Santa Cruz Island (Galapagos Is-
lands). Oldenburg, Germany: University of Oldenburg. Pp. 1-102.
Kastdalen, A. 1982. Changes in the biology of Santa Cruz 1935-1965. Not.
Galapagos 35:7-12.
Macdonald, I.A.W., L. Ortiz, J. E. Lawesson, and J. B. Nowak. 1988. The
invasion of highlands in Galapagos by the red quinine-tree Cinchona
succirubra. Environ. Conserv. 15:215-220.
Meyer, J.-Y. 2000. Preliminary review of the invasive plants in the Pacific
islands (SPREP Member Countries). In G. Sherley, ed. Invasive Species
in the Pacific: A Technical Review and Draft Regional Strategy. Apia,
Samoa: South Pacific Regional Environment Programme. Pp. 85-114.
Renteria, J. L. 2002. Ecología y manejo de la cascarilla (Cinchona pubescens
Vahl), en Santa Cruz, Galapagos. Área Agropecuaria y de Recursos Naturales
Renovables. Loja, Ecuador: Universidad Nacional de Loja. Pp. 1-89.
Tuoc, L. T. 1983. Some thoughts on the control of introduced plants. Not.
Galapagos 37:25-26.
Wiggins, I. L. and D. M. Porter. 1971. Flora of the Galapagos Islands. Stan-
ford, CA: Stanford University Press. Pp. 16-30, 695-697.
2004
Invasive Weed Symposium
A Journal of the Weed Science Society of America
Table of Contents
Preface
1180 Invasive Plants in Natural and Managed Systems. Proceedings of the IPINAMS Conference as a
Special Edition of Weed Technology. Nelroy E. Jackson
1182 Prevention, Early Detection, and Rapid Response to Invasive Plants. Presentation by Deputy Under
Secretary Lambert. Charles Lambert
Symposium
1185 Linking Science and Management to Mitigate Impacts of Nonnative Plants. Guy R. McPherson
1189 A Framework for Prioritizing Sleeper Weeds for Eradication. David C. Cunningham, Simon C. Barry,
Gemma Woldendorp, and Melissa B. Burgess
1194 The Control of a Highly Invasive Tree Cinchona pubescens in Galapagos. Christopher E. Budden-
hagen, Jorge Luis Renteria, Mark Gardener, Sarah R. Wilkinson, Monica Soria, Patricio Yanez, Alan
Tye, and Rene Valle
1203 Assessment of the Abundance and Distribution of the Aquatic Plants and Their Impacts in the Senegal
River Delta: The Case of Khouma and Djoudj Streams. Ousmane Fall, Ibrahima Fall, and Nobuyuki
Hori
1210 Successional Changes in Himalayan Alpine Vegetation: Two Decades After Removal of Livestock
Grazing. Chandra Prakash Kala and Rahul J. Shrivastava
1213 Microclimatic Constraints and Revegetation Planning in a Variable Environment. Stuart P. Hardegree
and Steven S. Van Vactor
1216 Biology of Pathways for Invasive Weeds. Charles T. Bryson and Richard Carter
1221 Insights to Invasive Species Dynamics from Desertification Studies. Debra P. C. Peters, Jin Yao, and
Kris M. Havstad
1226 The Exotic Flora of Chad: A First Contribution. Giuseppe Brundu and Ignazio Camarda
1232 Implications of Invasive Species for Belowground Community and Nutrient Processes. Joan G.
Ehrenfeld
•Peer reviewed papers.
Cover
Awareness of invasive weeds, such as Kudzu (Pueraria montana) has increased in recent years. This image was taken
by Dr. Shawn Askew, Department of Plant Pathology and Weed Science at Virginia Polytechnic and State University,
Blacksburg, Virginia 24061.
... It was originally planted in the agricultural zone of Santa Cruz at middle elevation (~250 m) (Valdebenito 1991), just below the area that now belongs to the National Park. By 1965, a few quinine plants were established "above the timber line" in the (Buddenhagen et al. 2004). A more recent assessment using satellite imagery estimates the current distribution as low as 1541 ha (Trueman et al. 2014), which could be due to a different method used, management actions carried out by the GNPD or a recent natural dieback of the species (see "Conclusions" at the end of this chapter). ...
... Quinine has long been recognized as a potential risk to the native Galapagos flora, and for the last 35 years staff from Galapagos National Park Directorate and the Charles Darwin Foundation have worked on identifying the best method to eliminate this species (Buddenhagen et al. 2004). Some of the manual methods that have been attempted include felling and uprooting trees, but the fact that trees re-sprout from cut stumps makes these methods very inefficient (Macdonald et al. 1988;Buddenhagen et al. 2004). ...
... Quinine has long been recognized as a potential risk to the native Galapagos flora, and for the last 35 years staff from Galapagos National Park Directorate and the Charles Darwin Foundation have worked on identifying the best method to eliminate this species (Buddenhagen et al. 2004). Some of the manual methods that have been attempted include felling and uprooting trees, but the fact that trees re-sprout from cut stumps makes these methods very inefficient (Macdonald et al. 1988;Buddenhagen et al. 2004). Several methods of herbicide application have also been tested, including basal bark, cut stump, girdle and squirt, branch filling, tree injections, and foliar spraying (Buddenhagen et al. 2004). ...
Chapter
To assess the effects of guava on the community of soil invertebrates, we compared carbon and nitrogen concentrations in soil and plant tissues, and the diversity of soil invertebrates, between two areas with similar altitude and climate but which differ in the presence of guava in the highlands of San Cristobal Island. On the other hand, to analyze how guava could be affected by animal communities, we present a preliminary evaluation of introduced mammals’ role as seed dispersers of this invasive species.
... Quinine had completely naturalized by 1972 and could be found at an altitude of 580 m as scattered small trees between Miconia robinsoniana shrubs and in the central part of the island (Hamann 1974). Quinine distribution reached around 1619 ha in 1976 (Moll 1990), 4000 ha in 1987 (Ortiz and Lawesson 1987), 8500 ha in 1990 (Moll 1990), and over 11,000 ha in 2004 (Buddenhagen et al. 2004). A more recent assessment using satellite imagery estimates the current distribution as low as 1541 ha (Trueman et al. 2014), which could be due to a different method used, management actions carried out by the GNPD or a recent natural dieback of the species (see "Conclusions" at the end of this chapter). ...
... Quinine has long been recognized as a potential risk to the native Galapagos flora, and for the last 35 years staff from Galapagos National Park Directorate and the Charles Darwin Foundation have worked on identifying the best method to eliminate this species (Buddenhagen et al. 2004). Some of the manual methods that have been attempted include felling and uprooting trees, but the fact that trees re-sprout from cut stumps makes these methods very inefficient (Macdonald et al. 1988;Buddenhagen et al. 2004). ...
... Quinine has long been recognized as a potential risk to the native Galapagos flora, and for the last 35 years staff from Galapagos National Park Directorate and the Charles Darwin Foundation have worked on identifying the best method to eliminate this species (Buddenhagen et al. 2004). Some of the manual methods that have been attempted include felling and uprooting trees, but the fact that trees re-sprout from cut stumps makes these methods very inefficient (Macdonald et al. 1988;Buddenhagen et al. 2004). Several methods of herbicide application have also been tested, including basal bark, cut stump, girdle and squirt, branch filling, tree injections, and foliar spraying (Buddenhagen et al. 2004). ...
Chapter
One of the most invasive species in Galapagos Islands is the red quinine tree, Cinchona pubescens Vahl (Rubiaceae). Though considered rare and endangered in its native range in Ecuador, quinine is being controlled as an invasive and used as a timber source in Galapagos. Introduced to Santa Cruz Island in the 1940s, it started spreading in the 1970s and now covers a vast area in the humid highlands of the island. Quinine is considered an ecosystem engineer, changing plant species diversity and abundance as well as impacting endemic birds in the invaded area. It also alters the microclimate and increases phosphorus concentrations in the soil. The production of abundant small and wind-borne seeds, paired with a vigorous vegetative reproduction, makes it a very successful invader. Quinine is manually and chemically controlled by Galapagos National Park Directorate, but this method requires constant follow-up control of seedlings germinating from the seed bank. In addition, disturbances caused by these control measures seem to facilitate the establishment of other introduced plant species, especially blackberry (Rubus niveus). The quinine invasion in Galapagos Islands provides an opportunity to help understand the ecology of plant invasions in Galapagos and in island ecosystems in general.
... In the Galápagos National Park, several control methods to combat C. pubescens have been implemented. Manual methods include felling and uprooting of trees, as well as hand-pulling of smaller plants, but trees resprout from cut stumps [8,46]. Chemical control methods consist of applying herbicides by a range of means: hack and squirt, basal bark, cut stump, girdle and squirt, branch filling, tree injections, and foliar spray [8]. ...
... Manual methods include felling and uprooting of trees, as well as hand-pulling of smaller plants, but trees resprout from cut stumps [8,46]. Chemical control methods consist of applying herbicides by a range of means: hack and squirt, basal bark, cut stump, girdle and squirt, branch filling, tree injections, and foliar spray [8]. However, most of these methods were ineffective in the long run. ...
... Eventually, a hack and squirt technique was developed in which a mixture of picloram and metsulfuron was applied to connecting machete cuts around the circumference of tree trunks, which killed 73100 % of the trees. Smaller shoots and saplings were pulled out by hand [8]. This method is now successfully applied for C. pubescens control by the Galápagos National Park Service on a small scale, as well as the uprooting of trees in conservation priority areas [38]. ...
Article
Full-text available
Cinchona is the most commercially important genus of the family Rubiaceae (coffee family) after the genus Coffea, which produces the coffee of commerce. The genus Cinchona comprises 23 species of tropical evergreen trees and shrubs, which are distributed from Costa Rica to Bolivia. C. pubescens grows at altitudes between 300 and 3300 m. It is a tree with broad leaves and white or pink fragrant flowers arranged in clusters. C. pubescens has been cultivated in several tropical regions of the world for its quinine-containing bark and roots. Quinine was used as a remedy to treat malaria and therefore had significant economic importance from the 17th to the beginning of the 20th century. In 1944, quinine was synthesized and therefore C. pubescens lost much of its importance, but natural quinine is still used both where the synthetic is not available and for other medicinal purposes. The genus Cinchona was named after the COUNTESS OF CHINCHÓN, wife of the Viceroy of Peru, by the Swedish botanist LINNAEUS in 1742. According to the well cited legend, the countess was cured of malaria by having been administered the bark of Cinchona in 1638 after all other remedies failed. Although this story is not true, Cinchona ever since was frequently used as a malaria remedy, especially distributed by the Jesuits in their world travels. Cinchona is the national tree of Ecuador and is on the coat of arms of Peru.
... We need to pay attention to the spread of C. pubescens around the world due to the large areas of increased habitat suitability (Table 3). Cinchona pubescens is a widely cultivated tropical species that invades a variety of forest and non-forest habitats (Buddenhagen et al., 2004). It spreads by wind-dispersed seeds, and vegetatively via suckers up to several meters away from the original tree once established (Buddenhagen et al., 2004). ...
... Cinchona pubescens is a widely cultivated tropical species that invades a variety of forest and non-forest habitats (Buddenhagen et al., 2004). It spreads by wind-dispersed seeds, and vegetatively via suckers up to several meters away from the original tree once established (Buddenhagen et al., 2004). Hence, appropriate wind speeds may promote the expansion of C. pubescens across different habitats of biomes. ...
... Hence, our results provide a reference for the introduction of wind-dispersed non-native plants, with a perspective on the relationship between wind and species distribution. We need to delineate hotspots of biomes with positive effects of wind on habitat distribution, and consider wind speed effects for the prevention and control of plant invasion (Buddenhagen et al., 2004;Trueman et al., 2014). ...
Article
A number of widespread invasive plants are wind-dispersed, and wind may facilitate their dispersal and migration over a large distance. While wind is an important factor for seed dispersal and pollination, few studies have examined its potential to affect the habitat distribution of invasive plants over large spatial scales. We selected six of the world's worst invasive plants with wind-driving seed dispersal and pollination, and used wind speed as an indicator of wind. Environmental niche modelling was used to quantify the effects of wind on the habitat distribution of these invasive plants on a global scale and across 14 biomes. Wind had a negative effect on the habitat distribution of invasive plants in tropical and subtropical moist biomes, and a positive effect in Temperate Conifer Forests, Boreal Forests/Taiga, Temperate Grasslands, Savannas and Shrublands, and Montane Grasslands and Shrublands. We concluded that wind affected the habitat distribution of wind-dispersed invasive plants over a large scale, and this effect varied across different biomes. Thus, wind speed and biomes should be used as global monitoring indicators of invasion by wind-dispersed plants and wind speed variables should be included in the projection of habitat distributions of such invasive species when using ENM.
... These results paint a sobering image of the prospect of excluding introduced plants within park boundaries, which is why conservation practitioners extort the urgency of early monitoring and control actions both in GNP and private lands to keep them cost-effective (C. Buddenhagen & Renteria, 2009;Guézou et al., 2010;Rentería & Buddenhagen, 2006). The biology of introduced plant species and the context in which they grow must meet strict criteria to attempt plant control or eradication programs (C. ...
Chapter
Full-text available
Human activities and booming tourism industries are altering the stability of ecosystems in the Galapagos Islands. Managing the impacts of these changes depends primarily on how scientists and decision-makers conceptualize human relationships with the environment. The impacts and responsibilities of the solutions pursued by decision-makers most acutely affect human populations who inhabit the frontiers between human-dominated and natural areas. The most common narrative about the Galapagos refers to the archipelago as a natural laboratory. In the latter half of the twentieth century, this imaginary not only justified the establishment of the Galapagos National Park and scientific institutions like the Charles Darwin Research Station, but also fueled a burgeoning tourism industry. However, a new narrative started to emerge under the influence of fields such as systems science and political ecology: the discourse of Galapagos as a coupled human-natural system. I performed a literature review to trace these two narratives in scientific publications. Using a semiotic device (Greimas, Structural semantics: An attempt at a method. Lincoln: University of Nebraska Press, 1983) that highlights how the relationships among elements in a system produce their meanings, I mapped out the discursive boundaries between humans and pristine ecosystems for the first narrative, and between agriculture and conservation for the second narrative, as well as the oppositional relationships that define each of the respective concepts. The natural laboratory narrative is heavily based on dualisms between human and nature, as well as on idealized notions of pristine landscapes devoid of human influence. Breaking down the natural laboratory narrative evidences how important the myth of the pristine has been in erasing human history from the imaginary of the Galapagos and in privileging both the conservation and tourism sectors over other economic activities. Meanwhile, the coupled human-natural system narrative acknowledges the influence that humans have had on landscapes throughout human history and recognizes the role that they can have in their conservation. These narratives and the differences between them come into play when authorities discuss development models for the region and potential solutions for the problems that Galapagos faces. While the first narrative has usually proposed solutions based on excluding people from protected areas and regulating land uses that do not fit their vision, the second narrative focuses on the function that people can serve and seeks to involve people outside of protected areas into conservation work and to include different land uses as potential allies for conservation. The first narrative is compatible with the way ecotourism was conceived, as an activity that would promote economic growth while having a limited impact on the environment. The second narrative is consistent with the concept of novel ecosystems because it is a functional perspective that focuses on promoting and maintaining positive relationships between humans and their environment. I argue that including the agricultural sector into the vision for conservation of the Galapagos can have tangible benefits for the control of invasive plants, for the protection of charismatic megafauna, for the region’s food security, and the population’s socioeconomic stability. Much like a gardener who must judge what seeds to sow and must work to keep what they believe belongs on their land and what does not, it is human agency (or lack thereof) that determines what will flourish on humanity’s Galapagos Garden.
... Namun kini jenis ini tidak hanya diketahui sebagai jenis tumbuhan invasif, namun termasuk ke dalam daftar 100 the world's worst invasive alien species-IUCN (Lowe et al 2004;Global Invasive Species Database 2017). Jenis ini diketahui telah menginvasi kawasan Hawaii, Galapagos, terutama di dataran tinggi kawasan Pasifik, namun demikian ternyata di habitat aslinya di Ekuador, jenis ini kini telah langka (Richardson 1998;Buddenhagen et al. 2004;Jager 2015). ...
Conference Paper
Full-text available
Abstrak. Mutaqien Z. 2017. Pendugaan pelepasan senyawa alelopati pada proses dekomposisi serasah daun tumbuhan invasif: Calliandra calothyrsus dan Cinchona pubescens. Pros Sem Nas Masy Biodiv Indon 3: 334-338. Jenis asing invasif adalah salah satu faktor utama penyebab perubahan dramatis pada berbagai sistem ekologi di seluruh dunia dan disinyalir sebagai salah satu penyebab utama kepunahan jenis asli. Namun masih diperlukan banyak pekerjaan untuk memahami bagaimana mekanisme, termasuk peran alelopati pada berbagai jenis tumbuhan invasif. Cinchona pubescens Vahl. dan Calliandra calothyrsus Meissn. diketahui sebagai jenis invasif di beberapa tempat, bahkan C. pubescens termasuk salah satu dari 100 organisme paling invasif di dunia. Penelitian ini merupakan studi pendahuluan dari dugaan adanya mekanisme alelopati yang berasal dari proses dekomposisi daun dari dua jenis tumbuhan invasif tersebut. Percobaan perkecambahan Vigna radiata (L.) R. Wilczek dengan Rancangan Acak Lengkap dengan dua perlakuan berupa pemberian cairan rendaman daun C. pubescens dan C. calothyrsus dengan masa rendaman 7-180 hari dengan masing-masing tiga kali ulangan dilakukan untuk merepresentasikan proses penyebaran alelopati melalui proses dekomposisi yang mungkin terjadi di alam. Panjang akar dan batang kecambah diukur dan diproses menggunakan Anova dan uji lanjutan Ducan. Air rendaman daun C. calothyrsus tidak berpengaruh nyata pada perkecambahan V. radiata. Air rendaman C. pubescens berpengaruh nyata terhadap perkecambahan. Diduga kuat terdapat senyawa alelopatik yang dilepaskan pada proses dekomposisi daun C. pubescens. Semakin lama proses dekomposisi, semakin berkurang dampaknya terhadap perkecambahan. Abstract. Mutaqien Z. 2017. Presumption of allelopathic compound(s) released in the leaf litter decomposition process of invasive plants: Calliandra calothyrsus and Cinchona pubescens. Pros Sem Nas Masy Biodiv Indon 3: 334-338. Invasive alien species is one of the main cause of ecological systems dramatically changes and also native species extinction worldwide. However, more studies are needed to discover its mechanism, including role of allelopathy compound in invasive plants competition. Cinchona pubescens Vahl. and Calliandra calothyrsus Meissn. are recorded as invasive species in some regions. Moreover, C. pubescens is stated as one of 100 of the world's worst invasive alien species by IUCN. This study aimed to confirm indication of the existence of allelopathic mechanism in invasion process of these two invasive alien species by releasing allelopathic compound(s) from its leaves fall over decomposition process. To clarify this hypothesis, a preliminary study had been conducted by testing the effect of the compounds released from decomposition process over the times (7-180 days) to germination of Vigna radiata (L.) R. Wilczek in the laboratory. Completly Randomize Design was used by applying liquid produced by decomposition process of these two invasive species and control (three repetitions) to test its effects. Radicles and hypocotyls length were measured, compared and Anova analyzed by using R-statistic 3.1.3. Germination of V. radiata only significantly inhibited by compound(s) released by decomposition processes of C. callisaya's leaves. Its inhibition effect was reduced over the times
Article
Full-text available
Chapter
The challenge of accommodating a growing human population on these ecologically distinctive islands seems intractable. Conventional approaches to building form, urban design, and planning controls are trivial and ineffective. Recent platitudinous approaches to more sensitive settlements on the islands are demonstrably irrelevant, the results ineffectual. Thus we have sought an alternative framing of the challenge to model a response. The CAS approach, engaged by the Galapagos Science Center in its work on the ecosystem and economy of the islands, offers this alternative (Wesley F, Carpenter SR, Brock WA, Holling CS, Gunderson LH (2002) Why systems of people and nature are not just social and ecological systems. In: Gunderson LH, Holling CS (eds) Panarchy. Island Press, Washington, DC, pp 103–119). In this chapter we report the outcomes of an exercise conducted in the context of a design studio in which propositions for possible future urban development were explored informed by CAS theory. The Holling cycle of adaptive change is used as a model to examine urban interventions to describe a transition to sustainable urban form. The cycle is then embedded into a panarchy model to contextualize the urban change in the larger environment and inform it with human action through the development of local knowledge.
Article
Full-text available
Terrestrial invasive species have been identified as one of the largest threats to endemic plants and wildlife in Galapagos and their spread remains one of the biggest challenges for the region. The management of these species is a common link among all land use activities and their spread impacts all residents as economic activities in Galapagos are linked to its status as a unique landscape. The study aims, through the use of key informant interviews, policy documents and literature, to provide new insights into plant invasive species management by exploring two land use interventions ‐ and the associated challenges and opportunities – currently being proposed by policymakers, academics and other relevant actors. These are 1) local sustainable agricultural production and 2) policies and mechanisms, specifically the ‘Buen vivir’ paradigm with/and Payments for Ecosystem Services (PES). It explores how these can create bridges and be beneficial to both conservation and development. However, whilst the initiatives offer real opportunities to manage and control invasive species, challenges remain in the form of how these activities will be carried out and by whom. Findings show that probable success is dependent on community inclusion with coordinated and integrated approaches from robust institutions with connectivity among land use actors/managers. In addition, support is needed for organisations/stakeholders that are currently tackling the invasive species issue. Studies on land use remain crucial as relatively contained and pristine landscapes such as Galapagos are likely to be increasingly important as a means to detect human‐induced alterations at the frontiers of ecology.
Chapter
A fused, multi-scale remote sensing system that ranges from field-based to satellite-based systems offers considerable power and efficiencies for mapping and monitoring the spread and/or eradication of introduced and invasive plant species. Optical, multispectral, and hyperspectral remote sensing systems are capable of distinguishing alien species from background features through their spectral, spatial, and temporal signatures—often assessed through a suite of change detection approaches that rely upon an assembled image time series. Pixel- and object-based image processing approaches depend on an expanded feature set that generally includes digital enhancements and vegetation indices as well as GIS coverages. Several land suitability and ecosystem process models have been used to assess the spread of introduced and invasive species across the landscape, given ecological site conditions and social considerations associated with human-managed landscapes. Considerable challenges persist in the mapping, monitoring, and modeling of introduced and invasive species related to sub-canopy distributions, target resolutions of young and mature specimens, fragmented distributions, and natural and human forcing functions of their space-time patterns across the landscape.
Article
One of the problems bedevilling both scientific research and conservation in the Galapagos is the difficulty in discovering how far changes are due to man and the animals and plants he has introduced and how far they result from climatic variations and other factors. Records have been kept since the Darwin Research Station was set up but we lack data on earlier periods which could throw much light on today's problems. Fortunately Mr. Kastdalen, a farmer and gifted naturalist, recorded many years ago the changing fortunes of plants and animals which he had noted during the three decades before the inauguration of the CDRS. Since then there have been further changes. His observations of the fluctuations in animal and plant life are of great value, and fill a gap that would otherwise have remained a blankfor ever. We are most gratefulfor his permission to print this account. This paper is not the product of special research but only of observations which I have been able to make as occasion permitted. The years and dates are in some cases only approximate because I have kept no notes until now. We came here on August 12, 1935. From then until about the year 1941 it was much wetter than it has been later, although 1953 was also very wet. To illustrate this change, a creek near our house used to flow, on average, about five times per year in our first years here, and once, in about 1939, flowed 14 times; but it has now been dry since 1953. On the other hand, it seems that the garua (heavy mist) has actually been more intense during the last 20 years or so than for a long time before. Some of the effects of these climatic changes will be mentioned in the sections that follow.
Article
The alien tree species Cinchona succirubra , the Red Quinine-tree (Rubiaceae), was introduced to the Galápagos Islands, Ecuador, in 1946, for purposes of cultivation, but causes much concern as, by 1987, it was found to cover about 4,000 hectares in the highlands of Santa Cruz Island, changing the original, largely endemic, vegetation. Some limited herbicide trials have been made by the Galápagos National Park Service, but a really successful method of controlling this pest still remains to be found. The removal of Cinchona plants from a 1000-ha Intensive Control Area (ICA) within the Galápagos National Park has been successful to date. However, large stands of the tree exist in the adjacent agricultural area of Santa Cruz Island, as well as elsewhere in the National Park. With the maturation of these stands, an increased input of Cinchona succirubra seeds to the ICA can be anticipated. Strengthened use of manual, chemical, and biological, control measures are therefore recommended on a shortterm basis, in order to conserve the unique highland vegetation of Santa Cruz Island, Galápagos.
Impact of the Introduced Tree Cinchona pubescens Vahl On the Native Flora of the Highlands of Santa Cruz Island (Galapagos Islands)
  • H Jäger
Jäger, H. 1999. Impact of the Introduced Tree Cinchona pubescens Vahl. On the Native Flora of the Highlands of Santa Cruz Island (Galapagos Islands). Oldenburg, Germany: University of Oldenburg. Pp. 1–102.
Preliminary review of the invasive plants in the Pacific islands (SPREP Member Countries) Invasive Species in the Pacific: A Technical Review and Draft Regional Strategy. Apia, Samoa: South Pacific Regional Environment Programme
  • J-Y Meyer
Meyer, J-Y. 2000. Preliminary review of the invasive plants in the Pacific islands (SPREP Member Countries). In G. Sherley, ed. Invasive Species in the Pacific: A Technical Review and Draft Regional Strategy. Apia, Samoa: South Pacific Regional Environment Programme. Pp. 85–114.
Ecología y manejo de la cascarilla (Cinchona pubescens Vahl), en Santa Cruz, Galápagos. Área Agropecuaria y de Recursos Naturales Renovables. Loja, Ecuador: Universidad Nacional de Loja
  • J L Rentería
Rentería, J. L. 2002. Ecología y manejo de la cascarilla (Cinchona pubescens Vahl), en Santa Cruz, Galápagos. Área Agropecuaria y de Recursos Naturales Renovables. Loja, Ecuador: Universidad Nacional de Loja. Pp. 1–89.
Some thoughts on the control of introduced plants
  • L T Tuoc
Tuoc, L. T. 1983. Some thoughts on the control of introduced plants. Not. Galapagos 37: 25-26.
Changes in the biology of Santa Cruz 1935-1965
  • A Kastdalen
Kastdalen, A. 1982. Changes in the biology of Santa Cruz 1935-1965. Not. Galapagos 35:7-12