INTERIM RECOVERY PLAN NO. 185
SCALY-LEAVED
FEATHERFLOWER
(VERTICORDIA SPICATA SUBSP.
SQUAMOSA)
INTERIM RECOVERY PLAN
2004-2009
Gillian Stack
1
, Alanna Chant
2
, Gina Broun
3
& Val English
4
1
Project Officer, WA Threatened Species and Communities Unit (WATSCU), CALM, PO Box 51 Wanneroo, 6946.
2
Flora Conservation Officer, CALM’s Geraldton District, PO Box 72, Geraldton 6531.
3
Flora Conservation Officer, CALM’s Moora District, PO Box 638, Jurien Bay 6516.
4
Acting Senior Ecologist, WATSCU.
Photograph: Anne Cochrane
October 2004
Department of Conservation and Land Management
Western Australian Threatened Species and Communities Unit,
PO Box 51, Wanneroo, WA 6946
Interim Recovery Plan for Verticordia spicata subsp. squamosa
2
FOREWORD
Interim Recovery Plans (IRPs) are developed within the framework laid down in Department of
Conservation and Land Management (CALM) Policy Statements Nos. 44 and 50.
IRPs outline the recovery actions that are required to urgently address those threatening processes most
affecting the ongoing survival of threatened taxa or ecological communities, and begin the recovery process.
CALM is committed to ensuring that Critically Endangered taxa are conserved through the preparation and
implementation of Recovery Plans or Interim Recovery Plans and by ensuring that conservation action
commences as soon as possible and always within one year of endorsement of that rank by the Minister.
This Interim Recovery Plan results from a review of, and replaces, No.49 Verticordia spicata subsp.
squamosa (Phillimore and English, 1999). This Interim Recovery Plan will operate from October 2004 to
September 2009 but will remain in force until withdrawn or replaced. It is intended that, if the taxon is still
ranked Critically Endangered, this IRP will be reviewed after five years and the need for a full Recovery
Plan assessed.
This IRP was given regional approval 9 November, 2004 and approved by the Director of Nature
Conservation on 7 December, 2004. The allocation of staff time and provision of funds identified in this
Interim Recovery Plan is dependent on budgetary and other constraints affecting CALM, as well as the need
to address other priorities.
Information in this IRP was accurate in October 2004.
ACKNOWLEDGMENTS
The following people have provided assistance and advice in the preparation of this Interim Recovery Plan:
Anne Cochrane
Manager, CALM's Threatened Flora Seed Centre
Andrew Crawford
Technical Officer, CALM's Threatened Flora Seed Centre
Elizabeth George
Verticordia specialist; Honorary Curator, WA Herbarium
Amanda Shade
Horticulturalist, Botanic Gardens and Parks Authority
Charles Strahan
Gardener and rare flora enthusiast, Shire of Three Springs
Thanks also to the staff of the W.A. Herbarium for providing access to Herbarium databases and specimen
information, and CALM's Wildlife Branch for assistance.
Interim Recovery Plan for Verticordia spicata subsp. squamosa
3
SUMMARY
Scientific Name:
Verticordia spicata subsp .
squamosa
Common Name:
Scaly-leaved Featherflower
Family:
Myrtaceae
Flowering Period:
October-December
CALM Region:
Midwest
CALM Districts:
Moora, Geraldton
Shires:
Three Springs, Mingenew
Recovery Teams:
Moora District Threatened Flora Recovery
Team and Geraldton District Threatened
Flora Recovery Team
Illustrations and/or further information: Brown, A., Thomson-Dans, C. and Marchant, N. (Eds) (1998) Western
Australia’s Threatened Flora, Department of Conservation and Land Management, Western Australia; George, E.A.
(2002) Verticordia: the turner of hearts, University of Western Australia Press, Western Australia in association with
Australian Biological Resources Study, Australian Capital Territory; Ginger, D. (1999) The Effects of Habitat
Fragmentation on two Rare and Endangered Verticordias, Honours Thesis, Curtin University of Technology, Western
Australia.
Current status: Verticordia spicata subsp. squamosa was declared as Rare Flora in June 1995. It is currently ranked as
Critically Endangered (CR) under the Wildlife Conservation Act 1950. The taxon is also listed as Endangered under the
Commonwealth Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). It currently meets Red
List (IUCN 2000) Category ‘CR’ under criteria A4c; Ba1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v); C2a(i); and D as there is a total
of only 29 mature individuals in seven extant wild populations with continuing decline in the quality of habitat. The
main threats include poor recruitment, weeds, edge effects, rabbits, road and fence maintenance and inappropriate fire
regimes.
Description: Verticordia spicata subsp. squamosa is a dense bushy shrub usually 30-60 cm but sometimes to almost 1
m tall, and 60-100+ cm wide. It has rounded to elliptic leaves, 1.5 - 2 mm long with prominent oil glands. The leaves
closely overlap and are pressed to the stem, providing the scaly appearance from which this subspecies derives its name
(from the Latin squamosus - scaly). The flowers are produced in early summer and are closely packed, forming dense
spikes on the ends of the branches. They open mauve-pink before the whole spike fades evenly to white with age, and
they have a stronger perfume than V. spicata subsp. spicata. The fringed sepals are 3-4 mm long and the petals are 2.5
mm long, with a 1-2 mm fringe. The stamens and linear staminodes are hairless. The style is 4 mm long and bearded
below the apex. (George 2002; Brown et al. 1998).
Habitat requirements: Verticordia spicata subsp . squamosa is known from nine populations in the Three Springs and
Mingenew areas of Western Australia, occurring over a range of approximately 20 km. All of the populations are small
and highly vulnerable to the effects of habitat fragmentation. Most populations are located on narrow road reserves, and
others occur on private property. Seven of the nine populations contain three plants or less.
Verticordia spicata subsp . squamosa grows in open mallee over low scrub on deep yellow sands. Associated species
include Eucalyptus jucunda, Actinostrobus arenarius, Jacksonia sp., Verticordia comosa, V. monadelpha, V. densiflora
var. stelluligera, V. eriocephala and Grevillea biformis.
Critical habitat: The critical habitat for Verticordia spicata subsp. squamosa comprises the area of occupancy of the
known populations; similar habitat within 200 metres of known wild and translocated populations; corridors of remnant
vegetation that link populations, and additional nearby occurrences of similar habitat that do not currently contain the
species but may have done so in the past and may be suitable for translocations.
Habitat critical to the survival of the species, and important populations: Given that this taxon is listed as Critically
Endangered, it is considered that all known habitat for wild and translocated populations is habitat critical to its
survival, and that all wild and translocated populations are important populations.
Benefits to other species or ecological communities:
Three Priority flora are known from the habitat of V. spicata
subsp . squamosa. These are Acacia lanceolata (Priority 2), Calytrix purpurea (Priority 2) and Pityrodia viscida
(Priority 3). In addition, recovery actions such as weed control or buffer vegetation planting at V. spicata subsp.
squamosa populations will help to protect the ecological community in which the populations are located.
International obligations: This plan is fully consistent with the aims and recommendations of the Convention on
Biological Diversity, ratified by Australia in June 1993, and will assist in implementing Australia’s responsibilities
under that Convention. Verticordia spicata subsp. squamosa is not specifically listed under any international treaty, and
therefore this plan does not affect Australia’s obligations under any other international agreements.
Interim Recovery Plan for Verticordia spicata subsp. squamosa
4
Role and interests of indigenous people: The Aboriginal Sites Register maintained by the Department of Indigenous
Affairs does not list any significant sites in the vicinity of these populations. Implementation of recovery actions under
this plan will include consideration of the role and interests of indigenous communities in the region, and this is
discussed in the recovery actions.
Social and economic impact: Some populations of Verticordia spicata subsp. squamosa occur on private land and
liaison will continue with regard to the future management of these populations. The implementation of this recovery
plan has the potential to have some social and economic impact, where populations are located on private property or
other lands not specifically managed for conservation. The occurrence of this taxon on an unconstructed road reserve
may affect whether a road can be constructed at that site in the future, and this may have some limited social impact.
Recovery actions refer to continued liaison between stakeholders with regard to these areas.
Evaluation of the plan’s performance: The Department of Conservation and Land Management in conjunction with
the Geraldton District and Moora District Threatened Flora Recovery Teams will evaluate the performance of this IRP.
In addition to annual reporting on progress with listed actions and comparison against the criteria for success and
failure, the plan is to be reviewed within five years of its implementation.
Existing Recovery Actions: The following recovery actions have been or are currently being implemented:
1.
Relevant land managers have been made aware of the location and threatened status of the taxon.
2.
Declared Rare Flora (DRF) markers have been installed at Populations 1, 3, 6a and 7.
3.
Populations 4b and 6b on private property were fenced in 1997 to prevent grazing and trampling of plants and
habitat.
4.
Juveniles at Populations 4b and 9T (translocated) have been protected from grazing within individual rabbit-proof
enclosures.
5.
Weed control has been undertaken at a number of populations on several occasions.
6.
Cutting material was collected by Botanic Gardens and Parks Authority (BGPA) staff in 1995 for propagation.
7.
Small quantities of seed have been collected from most populations over a number of years, and this is stored at
CALM’s Threatened Flora Seed Centre (TFSC).
8.
Research has been conducted into the taxon’s reproductive biology, seed bank dynamics and seed germination
physiology, particularly the response to smoke.
9.
Additional smoke trials have been completed.
10.
A translocation was initiated in 2001, and a second planting undertaken in 2002.
11.
An information sheet that describes and illustrates the taxon has been produced.
12.
Staff from CALM’s Moora and Geraldton Districts monitor all populations of the taxon.
13.
The Moora District and Geraldton District Threatened Flora Recovery Teams are overseeing the implementation of
this IRP.
IRP objective: The objective of this Interim Recovery Plan is to abate identified threats and maintain or enhance viable
in situ populations to ensure the long-term preservation of the taxon in the wild.
Recovery criteria
Criteria for success: The number of individuals within populations and/or the number of populations have increased
by ten percent or more over the five year period of the plan.
Criteria for failure: The number of individuals within populations and/or the number of populations have decreased by
ten percent or more over the five year period of the plan.
Recovery actions
1.
Coordinate recovery actions
10.
Collect seed
2.
Map critical habitat
11.
Continue translocation process
3.
Liaise with relevant land managers
12.
Seek long-term protection of habitat
4.
Implement weed control
13.
Investigate possibility of land acquisition
5.
Implement rabbit control
14.
Rehabilitate habitat
6.
Undertake watering if necessary
15.
Develop and implement a fire management strategy
7.
Stimulate regeneration
16.
Promote awareness
8.
Monitor populations
17.
Obtain biological and ecological information
9.
Conduct further surveys
18.
Review the need for a full Recovery Plan
Interim Recovery Plan for Verticordia spicata subsp. squamosa
5
1.
BACKGROUND
History
The first specimen of Verticordia spicata subsp. squamosa was collected north of Three Springs in 1951, and
the subspecies was described in 1991 (George 1991). Additional populations have since been located, and a
total of 34 mature plants are now known from eight wild populations and one translocated population. Seven
of the populations contain three mature plants or less. Population 2 has been cleared and no plants have been
seen at the site since 1992. It is extremely unlikely that any V. spicata subsp. squamosa propagules remain at
this site, as soil-stored Verticordia seed typically declines in viability quite rapidly. The plant at Population 3
died only recently (November 2003), so there is a chance that some seed may still remain at this site. Ginger
(1999) obtained seed viability results of 0% from this solitary plant during his tests, but attempts to stimulate
germination in the area should nevertheless be made. Very little of this habitat type remains uncleared in the
area, as the deep sands are suitable for agriculture. Most populations occur in tiny fragments of vegetation on
narrow road verges or private property.
A translocation was initiated in 2001 in an attempt to establish a larger population in habitat in good
condition. The taxon is extremely difficult to propagate as it has seed with relatively low viability, low
survival rates of seedlings, and a low strike rates of cuttings. In addition, setbacks have been experienced
with repeated watering system failures at the translocation site. It is likely that recovery of this taxon will
require plantings into the first translocation site for a number of years, and eventually planting into other
sites.
An Interim Recovery Plan (IRP) was developed for the subspecies in 1999 (Phillimore and English 1999).
Information collected since that plan was completed has been incorporated into this plan and this document
now replaces Phillimore and English (1999).
Description
Verticordia spicata subsp. squamosa is a dense bushy shrub usually 30-60 cm but sometimes to almost 1 m
tall, and 60-100+ cm wide. It has rounded to elliptic leaves, 1.5 - 2 mm long with prominent oil glands. The
leaves closely overlap and are pressed to the stem, providing the scaly appearance from which this
subspecies derives its name (from the Latin squamosus - scaly). The flowers are produced in early summer
and are closely packed, forming dense spikes on the ends of the branches. They open mauve-pink before the
whole spike fades evenly to white with age, and they have a stronger perfume than V. spicata subsp. spicata.
The fringed sepals are 3-4 mm long and the petals are 2.5 mm long, with a 1-2 mm fringe. The stamens and
linear staminodes are hairless. The style is 4 mm long and bearded below the apex (George 2002; Brown et
al. 1998).
Verticordia spicata subsp. squamosa differs from the typical subspecies in its smaller leaves and flowers. It
has been known to hybridise with V. comosa, with which it occurs. These hybrids tend to retain the habit of
V. spicata subsp. squamosa, but their dense spikes of creamy-white, strongly scented flowers are longer than
those of either parent. They usually have spreading leaves 2-3 mm long, a hypanthium with shorter
appendages, sepals with prominent auricles and a style 5 mm long with a more dense beard than that of V.
spicata subsp. squamosa (George 2002).
Distribution and habitat
Endemic to the Three Springs and Mingenew areas of Western Australia, V. spicata subsp. squamosa is
known from nine populations, most of which are located along narrow road reserves. Populations 4b and 6b
occur on private property, and Population 9T is a translocated population established in remnant vegetation
on private property. Population 5 occurs in a Shire gravel reserve, and Population 8 occurs on an
undeveloped Shire road reserve. Only 29 mature plants and three juveniles are known in wild populations,
with another three adult and 11 juvenile plants in the translocated populations. The taxon has a range of
approximately 20 km.
V. spicata subsp. squamosa grows in open mallee over low scrub on deep yellow sands. Associated species
include Eucalyptus ebbanoensis, E. jucunda, Actinostrobus arenarius, Grevillea biformis, G. eriostachya,
Jacksonia sp., Ecdeiocolea monostachya, Verticordia comosa, V. monadelpha, V. densiflora var. stelluligera
and V. eriocephala.
Interim Recovery Plan for Verticordia spicata subsp. squamosa
6
Biology and ecology
The genus Verticordia is well known for its colourful, showy flowers and most taxa in the genus have
horticultural potential. Few species have proved reliable in cultivation, however, and frequently a large
percentage of seed is infertile and germination is low (Wrigley and Fagg 1979). Most species make excellent
cut flowers and a considerable market has been established (Leigh et al. 1984).
A Verticordia spicata subsp. squamosa individual currently persisting in moderate condition was mature
when seen in 1974, and this suggests that these plants can live for at least 35 years.
Propagation of Verticordias has been mainly from cuttings with a few grown from seed. In general,
Verticordias produce only one seed per flower in the wild. Germination occurs from within old flowers that
have fallen to the ground. Research by CALM’s Threatened Flora Seed Centre (TFSC) has shown that seed
set is generally low in Verticordias (less than 51%) and is variable between species, within the same species
in different locations, and between different years at the same location (Cochrane and McChesney 1995).
Observations of V. spicata subsp. squamosa recorded extremely abundant flowering in 1993, with plants
appearing to ‘buzz’ as they were covered in native bees, moths, beetles, flies and ants. However, flowering
was scant in 1994, and no insects observed. Although seed set was not studied in those years, it could be
presumed to vary with the rates of flowering and insect visitation.
Verticordias are generally considered to be fire sensitive with post-fire regeneration occurring mainly from
seed. A few species have a lignotuber and can resprout after fire (E. George
1
personal communication). The
specific fire response of Verticordia spicata subsp. squamosa is unknown. Physical soil disturbance appears
to have a mildly positive influence on germination of seed, with two seedlings germinating after roadworks
at Population 1. There is also some suggestion that physical soil disturbance may foster the germination of
hybrids of Verticordia species; hybrids are seen in greater numbers in physically disturbed (although not
burnt) situations, and the mechanism for this is not understood (E. George, personal communication).
Verticordia species often hybridise readily. Verticordia spicata subsp. squamosa is known to hybridise with
V. comosa, with which it occurs in the wild (George 2002).
Verticordia spicata subsp. squamosa was found to be highly susceptible to infection by the plant pathogen
Phytophthora cinnamomi (dieback disease) when tested by CALM Science (C. Crane
2
, personal
communication). This finding is provisional as replication of the testing has necessarily been minimal, but
the results nevertheless provide an indication of the taxon’s susceptibility. The deep sands on which this
taxon occurs are generally low risk for dieback infection, and the area of occurrence receives less than 400
mm rainfall per annum. There is no record of the disease surviving in these conditions, so the risk to this
taxon in situ appears negligible.
There is a high level of exotic weed invasion and rabbit activity in the small remnants that contain
Verticordia spicata subsp. squamosa. This is likely to be impacting on ecological processes at these sites,
particularly with regard to recruitment of native taxa.
Research undertaken on Verticordia spicata subsp. squamosa in 1999 indicated that flower production is
high, with individual plants producing on average approximately 47,000 flowers (Ginger 1999). However, an
average of only 13% of these set viable seed, comparing poorly with V. spicata subsp. spicata which was
found to have seed viability of 40% (Tyagi 1993, cited in Ginger 1999). Seed viability of V. spicata subsp.
squamosa ranged from 21.7% at Population 4b (then 9 plants), through 9.6% at Population 6a (then 12
plants), 7.3% at Population 6b (then 7 plants) to 0% at Population 3 (then 1 plant) (Ginger 1999). The
number of plants present in each population closely corresponds to the quality of habitat at each site. The
trend of seed viability decline in association with smaller population size and habitat quality, to the extreme
of nil seed set at Population 3, has obvious implications for management. These findings strongly suggest
that larger populations in better quality habitat must be fostered to ensure their sustainability.
1
Elizabeth A. George, Honorary Curator, WA Herbarium
2
Colin Crane, Senior Technical Officer, Phytophthora research, CALM’s Science Division
Interim Recovery Plan for Verticordia spicata subsp. squamosa
7
Ginger (1999) assessed the presence of a soil-stored seed reserve at two Verticordia spicata subsp. squamosa
populations. Samples were collected from the drip-line around several plants at both sites, and an average of
649 fruits were found at one site, and an average of 462 fruits were found at the other. However, on average
only 3.2 and 4.4 fruits respectively contained viable seeds.
Research has shown some patterns in the effects of smoking and seed age on the germination of seed across a
wide range of species. Roche et al. (1997) found that seed ageing alone did not break dormancy in any of the
five Verticordia species examined (V. aurea, V. chrysantha, V. densiflora, V. eriocephala and V. huegelii). In
all five Verticordia species, smoking fresh seed after sowing improved the mean germination rates (0% in all
controls; 16.7%-42.8% with smoke treatment).
The viability of soil-stored seed was found by Roche et al. (1997) to decline over 12 months and is likely to
continue to decline with time. However, research indicates that the likelihood of the remaining viable seed in
the soil germinating can be increased by smoking the seed after 12 months soil storage. In four species,
smoking resulted in a dramatic improvement in germination as a percentage of seed viable at the time of
testing (eg, 28.1% of smoked fresh seed as compared to 91.7% of smoked aged seed; an improvement of
63.6% for V. densiflora). The fifth species had nil germination in any of the aged seed treatments.
The decline in seed viability of five Verticordia species over a period of 12 months was examined by Roche
et al. (1997). Viability declined from 60% initial viability to 40% viability after 12 months soil storage in V.
aurea (ie. a one-third decline). A decline of 26% to 3% viability was noted in V. huegelii (ie. a decline of
90%). As seed viability declines over time, the dramatic improvement in germination with smoke-age may
not yield the same level of improvement in number of germinants, but it is likely that the actual numbers will
still be higher. The results of Ginger’s and Chant’s trials so far suggest that V. spicata subsp. squamosa is
likely to follow the pattern of improved germination results with smoke application to slightly aged seed.
Population 4b is the only population to produce seedlings in situ, and this is consistent with the
comparatively high seed viability (21.7%) at that site. Four seedlings germinated in 2000 following summer
rain. They occurred in a smoke trial area set up by D. Ginger.
In his research on this taxon Ginger (1999) applied aerosol smoke using a fumigation tent. He reported better
response to smoking in May 1999 than in July 1998. This is in accord with Vigilante et al. (1998), who
suggest that smoke is best applied from autumn to early winter, or generally when germination is most likely
to naturally occur. Monitoring of the smoked sites in October 1999 reported 16 germinants at Population 4b,
although these were later identified to be other species (eg, Thryptomene and Scholtzia species). Forty six
germinants were also reported at Population 6b, but whether any of these were Verticordia spicata subsp.
squamosa is unknown, as this site was affected by cyclonic flooding and all seedlings died. No V. spicata
subsp. squamosa germinants were recorded from unsmoked soil at any site during the study. Subsequent
smoke trials were conducted by Alanna Chant in 2000, but these failed to stimulate germination. Possible
causes include low to nil levels of seed in the soil tested, and two successive very dry years in 2001 and
2002. It is hoped that another attempt followed by higher rainfall will provide better results.
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