Chicago Horticultural Society
Living Collections White Paper
July 2012
Table of Contents
Purpose.................................................................................................................................................. 1
Background ........................................................................................................................................... 1
Current and Future Efforts ................................................................................................................ 4
I. The Living Collection ............................................................................................................ 4
II. Use of the Collection ........................................................................................................... 17
Conclusion .......................................................................................................................................... 20
Appendices:
I. Criteria for Genus Selection for Specialized Collections ............................................... 22
II. Verification Profile Sheet .................................................................................................... 23
III. Plant Collecting Collaborative (PCC) Future Collecting Trips ..................................... 24
IV. Components of Specialized Collections ........................................................................... 25
i
Purpose
This paper addresses goals for living plant acquisition, development, care, and evaluation as well as
opportunities for research and education. It provides a systematic approach to improving and
diversifying the living collections at the Chicago Botanic Garden within the resource limits of space,
growing conditions, and labor.
Background
The Garden’s permanent plant collections cover 385 acres and currently hold over 2.5 million living
plants. These plants are of native and non-native origin and are found in the Garden’s public
terrestrial and aquatic displays. The current permanent Living Collection includes trees, shrubs,
vines, hardy perennials, and tropical plants, for a total of over 9,500 taxa. It is the quantity, diversity,
and health of these taxa, (or individual types of plants) along with documentation and public access,
that determine the quality and importance of a collection. This white paper focuses on the Garden’s
ornamental plants, as the native habitats are under the management of the Science division.
Herbaceous perennials are the Chicago Botanic Garden’s largest and most extensive collection of
plants. By definition, perennials continue to flower and fruit, year after year. Herbaceous perennials
do not form woody tissue and normally die down at some period of the year in response to
temperature, moisture, or light, and renew activity in the following growing season. At present, in
total there are over 2,301,000 herbaceous perennials (including bulbs, grasses, aquatics, and ferns),
which equates to 91% of the Garden’s total number of plants. Of the Garden’s 9,477 total taxa,
4,316 are ornamental perennial taxa (including bulbs, ferns, and grasses), or 46% of the Garden’s
total taxa. The Chicago Botanic Garden has the largest collection of documented and labeled hardy
herbaceous perennials on display in any public garden in North America. They range from oneinch-tall thyme to eight-foot-tall compass plant (Silphium laciniatum), and are displayed as specimens,
as groundcovers, in mixed borders, and integrated sweeps of thousands of plants.
Woody plants were the first permanent plants planted at the Chicago Botanic Garden. As the
Garden grew, woody plants were used in large masses for structure, to screen undesirable views, and
in smaller numbers in display gardens as examples of the best plants to be grown for Chicago area
landscapes. Currently, the hardy woody plant collection is composed of 3,519 taxa: 1,109 deciduous
trees, 1,517 deciduous shrubs, 721 evergreens, and 149 woody vines and 23 woody groundcovers.
The approximate number of woody plants in the Botanic Garden is 89,443.
The Botanic Garden’s woody plant collection is less diverse than arboreta (institutions specializing in
woody plants) with large acreage, such as the Arnold, Holden, Morton, and National Arboreta. The
Garden also lacks the historic collections these older institutions hold. However, the Garden has
one of the most extensive woody collections displayed in an ornamental garden setting
demonstrating landscape possibilities of any North American public garden. The Garden’s woody
plant collection has a large percentage of cultivars compared to other public collections and the
display and maintenance of these collections is recognized as one of the best.
Since its beginning, the Botanic Garden has seen incredible growth in its woody plant collection,
both in numbers of plants and taxa. In the past, when the collection was smaller, it was easy to find
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large trees and shrubs of new taxa to add to the many gardens being constructed. As the collections
grew, it became difficult to find new introductions to the collections. The Garden has had a
disproportionate amount of plants such as Austrian and Scots pine (Pinus nigra and P. sylvestris), red
oak (Quercus rubra and Q. coccinea), species ash (Fraxinus), and red twig and gray dogwood (Cornus
sericea and C. racemosa) planted in large masses for structure and screening. Many of these plants are
declining because of disease and soil problems. The heavy clay soil of the Garden, made worse
during construction, affects woody plants (with deep root systems) more than herbaceous plants.
As they become larger and their roots expand to support top growth, the poor soil adversely affects
them. White pine (Pinus strobus) is a classic example; many in the collection have been blown over or
have died of chlorosis. The Garden has many crabapples (Malus), but the collection needs to be
updated for more disease-resistant forms. There is a great opportunity to diversify the collections
content through plant replacement throughout the Garden.
The Garden is rich in taxa of maple (Acer), and new hybrids of large maples and smaller oriental
maples will be added to the collections. The Garden has room for more horsechestnuts and
buckeyes (Aesculus), hornbeam (Carpinus), cotoneaster (Cotoneaster), daphne (Daphne), deutzia
(Deutzia), beech (Fagus), hydrangea (Hydrangea), peony (Paeonia), mockorange (Philadelphus), cinquefoil
(Potentilla), oaks other than red (Quercus), stewartia (Stewartia), lilac (Syringa), linden (Tilia), elm
(Ulmus), and weigela (Weigela). More species and cultivars of these genera will be added. The
Garden has relatively few taxa of fir (Abies), birch (Betula), magnolia (Magnolia), pine (Pinus), cherry
(Prunus), and rhododendron (Rhododendron), but because of their soil and environmental
requirements, the Garden will never be strong in these genera and they will remain niche plants used
for accents and focal points. Due to their invasive nature, the Garden is not and will never be
strong in alder (Alnus), barberry (Berberis), euonymus (Euonymus), privet (Ligustrum), or honeysuckle
(Lonicera).
The Garden has a good rose collection in the Rose Garden and elsewhere. As many new varieties of
disease-resistant and hardy roses are introduced, the best of these will be incorporated into the
Garden’s collection. The Garden will not collect disease prone, non-hardy hybrid teas, floribundas,
grandifloras, etc., unless they are famous for historic, cultural, or horticultural reasons. The Garden
has a rosarian adviser for the collection. The Landscape Rose group (Rosa), those that are disease
resistant, low-maintenance, and hardy, has been named one of the Specialized Collections of the
Chicago Botanic Garden.
For the benefit of the Garden’s audience, students, donors, and displays, the Garden has developed
a woody plant collection of great variety. The acquisitions to the woody plant collection are
intended to represent the best plants for Upper Midwest gardens and landscapes, as well as the many
microenvironments in the greater Chicago region. These plants are the most disease resistant, hardy,
and beautiful plants for people to incorporate into their lives. They provide the structure of the
Botanic Garden’s landscape.
It is important that the plant collection is viewed as a museum living collection and not just
landscape decoration. The collection is an important genetic repository of native species, unusual
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non-natives, and well-adapted cultivars that fare well in the Garden’s environment. As such, they
are an important scientific resource for scholarly study, horticultural introduction, breeding efforts,
verified references, and the Garden visitor.
The plant collection serves many significant functions. These include:
 provide beauty as the living landscape of the Garden and the reason most people come to the
Garden;
 provides opportunities for research, such as plant evaluation and introduction;
 functions as a living encyclopedia for the students of the Joseph Regenstein, Jr. School of the
Chicago Botanic Garden and for children and teachers throughout the region;
 offers guidance for local gardeners and professional horticulturists in their horticultural and
landscape design choices;
 is a repository for rare and unusual plants and a gene pool for conserving wild-collected species
and cultivars;
 is significant enough to be part of a national program of germplasm preservation (the North
American Plant Collections Consortium).
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CURRENT AND FUTURE EFFORTS
Vision Statement: The Chicago Botanic Garden will have a world-class, public, Plant Collection.
Goals:
 Increase the size and diversity of the collection through a vigorous acquisition program
including plant exploration, purchases from commercial businesses, exchange from other
botanic institutions, and donations.
 Accumulate all taxa within each Specialized Collection and develop staff expertise, collectionsbased research, information dissemination, and impact on the horticultural marketplace.
 Insure the most accurate and timely data collection on plants.
 Oversee the health and care of the collections from their entry into the Garden through their
permanent place in the gardens.
 Share information about herbaceous perennials and plants with the public and professionals and
communicate with the largest possible audiences (both on and offsite) through print, broadcast,
and Internet distribution.
 develop the collection in quantity, quality, and variety;
 support collection maintenance;
 verify plants within collections;
 conduct collections-based research;
 increase staff support for collections development.
The purpose of the living collection is “to provide, for the public and professionals, an extensive
and current representation of the best ornamentals for the Midwest, and to maintain several
comprehensive generic collections as a repository of valuable germplasm.” – from the Plant
Collections Management Plan. The term “best ornamentals” refers to aesthetic attributes, local
cultural adaptability and compatibility, as well as disease and pest resistance and non-invasiveness.
I.
The Living Collection
A. Acquisition
As a museum, one of the Botanic Garden’s main goals is to collect objects, in this case, plants.
The curators’ main goals are to collect and curate the Garden’s collections. Plants are acquired
from other botanical institutions, private and commercial sources, selections made by gardeners,
plant exploration trips, seeds collected in-situ, and new hybrids produced by breeding efforts
from within and outside the organization.
Several criteria exist for acquisition. If wild-collected, they must be of known provenance.
Plants must be legally collected and imported. Plants with the potential for overly aggressive
behavior, genetic pollution, or that have the ability to introduce pests and diseases must be
screened and evaluated before provisional acceptance. Seed proposed for inclusion in the
permanent collections must originate from documented wild-collected or known sources to best
ensure genetic authenticity.
4
When new garden projects are started, the curators are involved with a several step process for
adding plants. The process starts with the design concept when plants appropriate to the area
need to be recommended to the landscape architect or otherwise incorporated into the design.
When the recommendations are approved, the appropriate curator sources the material and
subsequently inspects the plants to meet the standards of the Garden.
The focus of the plant collection follows the Garden’s mission “to promote the enjoyment,
understanding, and conservation of plants and the natural world.” To help advance this, the
collection will comprise the best plants for landscapes in the Upper Midwest and the best
compilation for teaching and preservation of germplasm for future generations. One of the
main functions of every museum is to collect objects. The Garden has four types of sources
from which to acquire plants – commercial firms, natural ecosystems, home garden enthusiasts,
and other botanical institutions.
The Garden’s primary source for acquiring new plants is from commercial firms. This source
provides the latest cultivars and plants bred for ornamental interest and disease resistance.
These are the plants most homeowners will be able to obtain and use in their own landscape.
To ensure plants are true to name, the Garden strives to acquire them from the originator.
Preserving germplasm of cultivated origin is becoming increasingly important. Often, when
cultivars fall out of favor, these taxa can be difficult to locate from commercial sources. Plants
of cultivated origin possess valuable genetic diversity and unique traits that may not be present in
wild species. The foundation for many plant breeding programs is cultivated germplasm. Most
institutions that specialize in storing germplasm in living collections or seedbanks primarily
house wild species and, to a lesser extent, cultivated taxa. The Garden is well positioned and has
the opportunity to maintain one of the largest living collections of cultivated germplasm.
Wild Collecting
When building living collections, great value is placed on plants that can be traced to an original
source or known provenance. Knowing where a plant comes from helps to authenticate that the
plant is true to name. Acquiring plants from known natural ecosystems is usually done through
expeditions to native and foreign sites, contracting with professionals to collect, or through seed
exchanges. The Garden collects plants from an analogous climatic band around the world –
roughly those taxa growing outdoors in temperate regions between the 35th and 55th parallels.
Plants for the Greenhouses come from latitudes beyond this range.
The reasons to acquire plants from the wild include:
 acquire germplasm that will be new to cultivation;
 acquire germplasm to supplement plants that are cultivated in limited numbers;
 extend the range of hardiness by collecting plants at their northern limits;
 evaluate new germplasm for better ornamental characteristics;
 evaluate new germplasm for insect and disease resistance;
 provide wild germplasm for breeding;
 provide learning experiences and professional development for staff;
5


preserve rare, endangered, and threatened species;
determine if plants have invasive tendencies.
The most cost-efficient way to conduct seed collecting expeditions is through a consortium of
gardens with similar interests. The Garden has on-going efforts to acquire wild collected,
documented germplasm through collaborative plant collecting expeditions and through
institutional seed and plant exchanges.
Plant Societies and Home Garden Enthusiasts
There are often plant experts or keen hobbyists who are self-taught and excel in gardening,
horticulture, and/or plant breeding. For example, Bill Radler, one of the country’s top rose
experts, has been invaluable in advising the Garden on roses. Curators will network and form
relationships with plant societies to procure new plants, discover plant cultivars, and identify
plants.
Other Botanical Institutions
The Garden also exchanges and acquires plants from other botanical gardens and arboreta that
have collections suitable to the upper Midwest climate. These plants will meet the Garden
standards for known provenance or otherwise determined to be true to name.
Over the past several years, total number of taxa has been decreasing at the Botanic Garden. If
curatorial staff is acquiring plants at a proper rate and horticulture staff are caring for them
properly, this is unacceptable. In 2011, with an increased emphasis on plant acquisitions and
reporting, this trend, hopefully, has been turned around.
One of the biggest problems with plants at the Garden has been the length of time they spend in
Plant Production before they are moved out to the display gardens/grounds. In 2011, a process
instituted by the Plant Production staff was put into place to move plants out from Plant
Production into the collections on a timely basis. This should improve the survival rate of the
plants, since they can only be kept growing so long in containers. It will also save the Botanic
Garden staff time in maintaining the plants.
6
Number of Taxa in CBG
# 10,000
9,000
o 8,000
f 7,000
6,000
5,000
T 4,000
a 3,000
x 2,000
a 1,000
0
Jan-12
Jan-11
Jan-10
Jan-09
Jan-08
Jan-07
Jan-06
Jan-05
Jan-04
Jan-03
Jan-02
Jan-01
Jan-00
Jan-99
Jan-98
Jan-97
Jan-95
Feb-96
Jan-94
Taxa
Year
Date
Jan-94
Jan-95
Feb-96
Jan-97
Jan-98
Jan-99
Jan-00
Jan-01
Jan-02
Jan-03
Jan-04
Jan-05
Jan-06
Jan-07
Jan-08
Jan-09
Jan-10
Jan-11
Jan-12
Plants
1,028,883
1,059,489
1,211,476
1,295,848
1,404,850
1,569,037
1,691,736
1,774,443
1,966,109
2,030,150
2,252,333
2,383,475
2,330,870
2,364,868
2,342,391
2,304,875
2,389,417
2,459,224
2,524,687
Change
30,606
151,987
84,372
109,002
164,187
122,699
82,707
191,666
64,041
222,183
131,142
-52,605
33,998
-22,477
-37,516
84,542
69,807
65,463
Taxa
6,762
7,258
7,559
7,398
7,641
8,043
8,514
8,463
8,819
8,704
8,310
8,747
9,434
9,439
9,414
9,252
9,289
9,084
9,477
Change
496
301
-161
243
402
471
-51
356
-115
-394
437
687
5
-25
-162
37
-205
393
Specialized Collections
The idea of “comprehensive generic collections” was originally established in the Garden’s
Collections Management Plan, approved in January 1991. Today, these are called Specialized
Collections and are genera of ornamental importance or an important part of local native
habitats. This group contains a large number of taxa that are well-adapted to the Chicago area,
7
thus allowing the Garden the potential to amass a large percentage of each genus. These
collections will become collections of distinction, recognized nationally and internationally. The
Botanic Garden will become an authority on these plants. Criteria for selection are outlined in
the Collections Management Plan; this list can be reviewed in Appendix I.
By developing Specialized Collections, the Garden will:
 add greater diversity in the collections;
 provide a greater opportunity for collections-based research;
 develop complementary staff expertise;
 disseminate information;
 provide a positive impact in the horticulture marketplace;
 become the world’s authority in specific perennial collections.
The Specialized Collections the Garden builds will interface with the United States Department
of Agriculture’s (USDA) National Plant Germplasm System (NPGS). Within the NPGS, the
Ornamental Plant Germplasm Center (OPGC) at The Ohio State University coordinates the
federal government’s Perennial Germplasm Repository. OPGC has identified 40 target genera.
Working together, both institutions can develop and safeguard the genera of mutual interest.
The cross-over genera, in order of priority according to both organizations are: Geranium
(geranium), Iris (iris), Solidago (goldenrod), and Symphyotrichum (aster). With the benefits and
proven results of the Garden’s Plant Exploration Program and Plant Collection’s plans for the
future, OPGC wants to work cooperatively with the Garden. The Garden’s Plant Exploration
Program has been so successful in bringing back valuable germplasm that the OPGC has
requested any and all germplasm resulting from these expeditions. So far, this has been a oneway street, with germplasm going from the Garden to OPGC. The Garden needs to try to find
ways to get germplasm back from the OPGC to enhance its collections.
The American Public Gardens Association (APGA) coordinates the North American Plant
Collections Consortium (NAPCC). There are two foci for the NAPCC: 1) to coordinate a
continent-wide effort among botanical gardens for the conservation of plant germplasm and
biodiversity and 2) to act as a mechanism for elevating the standards of curatorial management
of plant collections. As a NAPCC member, the Garden is part of a North American consortium
in which each garden agrees to conserve a certain segment of the plant population. The Chicago
Botanic Garden chose spirea because it tolerates heavy clay soils, is a relatively small shrub
requiring little space, has attractive flowers from spring through early summer; has a variety of
foliar coloration, has relatively low maintenance requirements, is versatile in its landscape uses,
and is used frequently in Upper Midwest landscapes. The Garden’s oak collection (Quercus spp.)
has also been accepted into the NAPCC as part of a Multi-institutional Collection. The Garden
is one of the 19 participating institutions representing all regions of the country for the Quercus
collection.
The Garden will submit its Specialized Collections to the North American Plant Collections
Consortium (NAPCC) of the American Public Gardens Association (APGA) where appropriate.
The Garden will apply for Narcissus in 2012. Of the nine native taxa of Schoenoplectus, the Garden
8
has nine. At this time, there are at least 16,600 taxa of Narcissus. Because there are so many taxa,
the Garden will focus on Division 7 (jonquila Narcissus), of which there are 385 taxa. Of these,
51 are commercially available. The Garden currently has 28 taxa of jonquil daffodils and will
focus on this division. Another focus is the genus Symphyotrichum (aster). The Garden currently
has all 17 taxa represented. The Garden applied for NAPCC status for Geranium in 2006, and it
was accepted. The components required to establish the Garden’s Specialized Collections are
outlined in Appendix IV.
There is still much work to be done. Three of the Specialized Collections groups, Symphyotrichum
(aster), Schoenoplectus (bulrush), and Carex (sedge), have been completed. The remaining genera
are in various stages of completion. The literature lists 385 within the jonquil division; 51 taxa
are commercially available some years. Similarly, for Geranium, we have discerned there are 503
that, hopefully, are appropriate for this Midwest region (Zone 2-Zone 6). We are now
determining which taxa are commercially available for these hardy Geranium and for Iris sibirica.
Within the subset of Siberians, the literature reflects 1,666 taxa.
A cross-departmental team selected the plants for the Specialized Collections while taking the
Garden resources of staff time, facilities, and available space into account. These plants provide
opportunities for evaluation and research and are appropriate to the cultural needs of the Upper
Midwest. They are also appropriate for the Garden’s endorsement of public use and education.
Specialized Collections effectively help the Garden to attain its goals, providing a variety in
specific genera of the collections that allows for the extent of research with specific groups of
plants characteristic of botanical institutions.
Taxa in Collection
Specialty Genera
Jan 11
Actinidia
15
Aesculus
34
Amelanchier
33
Carex – native
68
Cornus – non-bracted
74
Geranium
129
Ginkgo
39
Iris sibirica
72
Narcissus – jonquil
21
Quercus – IL native & cvs.
62
Rosa (Landscape)
48
Salix – 6' or less
23
Scirpus/Schoenoplectus – native 9
Solidago – native
10
Spiraea
87
Symphyotrichum (Chicago area) 18
Thuja plicata
25
Jun 12
19
32
35
67
72
135
36
73
33
66
54
27
9
10
88
19
33
9
% change
0%
-6%
9%
-1%
-4%
5%
-8%
1%
57%
3%
13%
17%
Complete
Complete
1%
5%
32%
Total Taxa
in Complete
Collection
52
77
55
82
150
281
94
1,725
55
84
132
216
9
10
148
22
76
The Garden’s woody Specialized Collections include: serviceberry (Amelanchier), ginkgo (Ginkgo),
spirea (Spiraea), oak (Quercus), hardy kiwi (Actinidia), dogwood (Cornus), rose (Rosa), willow (Salix),
western arborvitae (Thuja plicata), and buckeye (Aesculus). For the next five years, the Garden’s
focus will be on acquiring oak (Quercus), rose (Rosa), dogwood (Cornus), and buckeye (Aesculus).
Because the Garden’s spirea collection has been designated as a NAPCC collection, the Garden
considers building this collection a priority. The Chicago Botanic Garden currently has 88 taxa
of Spiraea (and could potentially hold 60 more taxa), placing the Garden as a leader in diversity
of spirea. This collection is a national and international resource for germplasm.
Ginkgo (Ginkgo) has only one species within its genus but cultivars vary by size, habit, and leaf
characteristics. The total number of plants that the Garden will collect is limited, due to its
mature size. This genus, a native to northern Asia, is hardy for the Garden and grows well in the
local soils. The Garden currently has 36 taxa and could add approximately 58 more taxa.
Oaks (Quercus) are an important part of the native landscape of the Upper Midwest. The most
common are bur oak and white oak. Current literature lists 12 species native to the Chicago
region1. The focus for collecting will be oaks native to the region and cultivated taxa that grow
well in alkaline clay soils. The Garden presently has 66 taxa and could add approximately 18
more taxa.
Serviceberries (Amelanchier) are short, multi-stemmed shrubs from 4’ tall to single stemmed trees
45’ tall. This group is valued for its early spring flowers, edible blue fruit in June, fall foliage
color, and tolerance to shade. Current literature lists five species that are native to the Chicago
region1. The Garden has 35 taxa and could add at least 20 more taxa.
Western arborvitae (Thuja plicata) is valuable in providing diversity among large evergreens,
which is limited due to heavy clay soils. It is also resistant to deer and a fast-grower. This
species and its cultivars are proving to be a better landscape plant for this region than the native
eastern arborvitae (Thuja occidentalis). The Garden has 33 taxa and could add approximately 43
more taxa.
The rose collection is the most beautiful and popular with the public out of all the Specialized
Collections. The rose collection is primarily in the Rose Garden, which has broad sweeps of
color with significant numbers of each plant. In the collection, the Garden holds 289 taxa. The
Garden will limit its future selection to those hardy landscape roses that are commercially
available and disease-free. For landscape roses that fit these two criteria, the Garden presently
has 54 taxa and could collect up to 78 taxa.
Because most dogwoods (Cornus) that have flowers with showy bracts are not adapted to the
Chicago climate, the Garden has limited its choice of dogwoods to those having flowers without
them. The Garden’s dogwoods exhibit shrubby habits and normally grow less than 16’. The
1
“Plants of the Chicago Region” by Swink and Wilhelm, 1994.
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current collection has 72 taxa and could add approximately 50 more taxa. The focus in the near
future will be on taxa of Cornus mas with plants to initiate an evaluation study of this group.
Willow (Salix) is a very large group of trees and shrubs. According to current literature, there are
more than 100 species the Garden could collect. A signature plant of the Garden is the weeping
willow; large numbers are planted around the lakes. The Garden has chosen to limit the plants it
will collect to shrubs and ground covers that naturally grow six feet or less, or ornamental forms
that are maintained at six feet. Currently, the Garden has 23 taxa but could add over 100 more
taxa.
Buckeye and horsechestnut (Aesculus) are an important group of woody plants that are widely
cultivated in Midwestern landscapes. The diversity in size, habit, and flowering time of Aesculus
species and cultivars offer many uses in gardens and urban landscapes. Buckeyes are adaptable
to a wide range of cultural conditions and most species and cultivars of this genus are hardy in
the Chicago region. The current literature lists 12 species and 96 taxa, including hybrids and
cultivars. The Garden will focus on hardy species, native and non-native, and available
cultivars. Currently, the Garden holds 32 taxa.
To round out the landscape components of trees and shrubs, the Garden selected hardy kiwi
(Actinidia) to represent vines. This vine is exhibited at the Fruit and Vegetable Garden and
performs well. Actinidia contains showy species and cultivars with variegated leaves and edible
fruit. The Garden has 15 taxa and could add approximately 40 more taxa.
The Garden will conduct a rigorous herbaceous perennial acquisition program to enlarge and
diversify the collection. A primary goal for the perennial collection is to increase the rate of
acquiring new taxa. The Garden’s perennial collection will continue to grow through the
acquisition of diverse species with an emphasis on the Specialized Collections. There are many
taxa of perennials the Garden does not yet grow. Many more are being discovered, selected and
developed all the time, creating an excellent opportunity to expand the Garden’s collections.
The Garden has space for many more taxa of herbaceous perennials. There are many plants of
redundant taxa in the current displays that can be replaced with new taxa. The number of taxa
in the Chicago Botanic Garden has seen a general downward trend over the last five years. For a
national organization which has the goal of a diverse collection of plants, this is unacceptable.
Increasing Variety in the Collection
The Garden’s environment with heavy, poorly drained soils puts trees under greater stress,
increasing their susceptibility to damaging insects and diseases and causes nutritional deficiencies
that limit growth and development. As a result, they die at a much younger age. The Austrian
pine (Pinus nigra), Scots pine (Pinus sylvestris), white spruce (Picea glauca), Colorado spruce (Picea
pungens), weeping willow (Salix alba ‘Tristis’), and ash (Fraxinus spp.) were initially planted in large
quantities. Due to the Garden’s difficult site and the stresses imposed on the plants, the
Garden’s trees are beginning to show early signs of old age. Declining and aesthetically poor
specimens of these trees should be replaced with scientifically documented plants with genetic
diversity.
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The original large-scale plantings of common plants easily purchased from nurseries that formed
the early framework of the Garden should be replaced with new accessions of scientifically
documented plants representing genetic diversity. The Garden will continue to increase the
percentage/quantity and taxonomic diversity of documented, wild-collected plants. The Garden
will aggressively remove plants that are redundant or that it has too many of. The Garden will
also develop accession duplicates of taxa that are unusual and have few specimens in the Garden
to insure collection integrity and to avoid potential catastrophic loss. The best botanic gardens
in the world effectively balance garden aesthetics and display with building a diverse and
documented living collection.
Upgrading the Collections Specialist position from seasonal to a permanent Assistant Curator of
Ornamental Plants position would greatly advance the curation of the plant collections,
including the woody plant collection. This person would be directly responsible for many facets
to diversify the collection for aesthetic appeal, for learning opportunities, and for research, and
study. The Assistant Curator would develop lists of new acquisitions for the Specialized
Collections by researching literature for flora lists and determining synonymy in nomenclature,
improve the quality of the collections, develop substitution lists for declining, redundant, and
invasive plants existing at the Garden, teach work on collections-based research, and help with
verification.
Through the support from an IMLS funded grant received in 2012, the temporary Assistant
Curator, Woody Plants will execute the Tree Health Assessment while also providing limited
support to other projects. The Curator of Woody Plants will continue to seek funding
opportunities in an effort to maintain this position if institutional resources are not available.
B. Documentation
Accuracy of data is of paramount importance to any museum. There are three primary
components to the Garden’s documentation procedures - Plant Records, Labels, and Maps.
These components are explained in detail in the Living Plant Documentation Plan.
A major problem with the plant documentation has been keeping track of plants in the records.
Plants were not always accessioned on a timely basis and communications noting transfers and
deaccessions were also lacking. The Plant Records staff now produces a monthly list of changes
in plant records that can be monitored by horticulturists and the curators to make sure
information is reported on a timely basis. Transparent and accessible information should
provide necessary feedback to all parties involved.
Tree Health Assessment Survey
A formal project to identify trees of poor health and in need of conservation treatment was
initiated in September 2011. The Institute of Museum and Library Services (IMLS) awarded the
Chicago Botanic Garden a Conservation Project Support Grant in 2012. The goals of the
project are to: 1) assess the current condition of 9,000 tree specimens; 2) identify the most
pressing areas of concern; 3) establish long-term conservation priorities and a care and
replacement plan for the collection; and 4) collaborate with the City of Chicago Department of
Environment to incorporate findings into an adaptive planting list.
12
The survey will include approximately 9,000 individual specimens of the more than 13,000 trees
within the permanent woody plant collections, defined as those located within the main tract and
enclosed by fencing. This number excludes arborvitae used in hedging, trees found in the
natural areas (McDonald Woods, Skokie River corridor, and Dixon Prairie), and trees planted in
the highway berm along the grounds’ west perimeter.
The Garden hired a temporary Assistant Curator to assign trees to good, fair, or poor health
categories, drawing on the expertise of the Curator of Woody Plants, Supervisor of Plant Health
Care, and the Horticulture staff. The Assistant Curator will add the resulting information to the
plant collection database and also inform living plant documentation staff of any inaccuracies in
mapping or labeling. Trees in poor health will be examined in further detail and an action plan
will be developed for them. If a specimen meets any one of three specific criteria: 1) extremely
limited in the collection; 2) collected in the wild; or 3) belongs to one of the Specialized
Collections, immediate follow-up will be recommended. Follow up will be limited to: 1) treat;
2) propagate; and/or 3) remove and replace. The survey will provide a baseline health
assessment for trees at an individual level, which is a critical first step in creating a conservation
and acquisition plan for the tree collection.
Also contributing to a long-term conservation plan will be computer modeling analysis to
predict potential impacts of climate change on select species. Conservation scientists will train
the assistant and the Curator of Woody Plants in how to conduct species distribution modeling,
with a goal of completing this activity on 10% of the taxa surveyed. Results of the survey and
computer modeling will also contribute to the City of Chicago’s Chicago Trees Initiative and its
development of an adaptive planting list for the Chicago Climate Action Plan. With the
Garden’s challenging site conditions, a comprehensive health assessment of the collection will
yield valuable information about performance and adaptability that can be used in the selection
of trees for similar conditions throughout the region and the Upper Midwest.
This project will be completed by the end of August 2013.
In July 2011, Emerald Ash Borer (EAB) was confirmed on Garden property through a
monitoring program initiated in 2006. The Garden will continue to follow its EAB Management
Plan (Appendix 1). The Tree Health Assessment survey will likely not identify EAB infected ash
since symptoms can take a few years to become obvious. Ash trees will be subject to closer
inspection during annual design walk-throughs.
C. Verification
Because the Garden’s collections are used for teaching, plant identification, propagation sources
for the commercial trade, other gardens, research subjects, and as examples for landscape
architects and their clients, it is important that they be accurately identified. The Garden’s
credibility as a museum relies in part on proper identification. Plants of known provenance may
be used in reintroduction programs when their populations in the wild fall to critical numbers.
Leading professionals in the perennial industry as well as educators want and need a trusted
reference. The Chicago Botanic Garden can provide this with verified Herbaceous Perennial
Collections that are available for view and study. If plants in the Collection are found to be
13
incorrectly named, they will require more than a cursory glance, and if greater examination is
inconclusive, then DNA technology could be employed to make this needed distinction.
The value of any collection depends heavily on the validity of the objects in the collection. If
these objects are not authenticated, they are not of value as a collection. This is true for living
and non-living objects. In 1990, the Chicago Botanic Garden began a Verification Program to
confirm the taxonomic identity of the Garden’s woody plants. There are currently two basic
methods to identify a plant:
1. Using morphologic, or physical, features that can be seen using, at most, a hand lens. This is
a classical taxonomic system originated by Karl von Linné.
2. Using chemicals to determine the genetic profile of cells. This more modern genotypic
system detects subtle differences between species and lower ranks such as subspecies, forms,
and varieties.
Currently, the former method is being used. The Curator chooses a genus based on the number
of different plants or taxa within the genus being grown at the Garden – usually a Specialized
Collection. Herbarium vouchers and photographs are taken and an expert on the chosen genus
is brought to the Garden to verify that the plant matches its description in the literature.
Plants are readily influenced by their growing conditions and so two identical plants can appear
to be different depending upon cultural conditions. Plant Verification Programs have used a
visual technique to determine a plant’s identity from a dried, often colorless, herbarium
specimen. This has been the standard and is reasonably accurate.
Herbarium vouchers are a means of verifying taxa for identification purposes. This technique is
used with genera that are conducive to being dried and stored for identification. In some
instances, the Garden has herbaria for genera that are conducive to that format and other taxa
are being verified with digital imagery. DNA sampling has begun for some groups. This newer
technique holds promise for verification in the future.
In 2003, the Astilbe (False Spirea) collection was visually verified with Dr. David Beattie, a
Professor of Horticulture at Penn State University and Director of The Center for Green Roof
Research. Dr. Beattie is recognized as an authority on the genus. In 2004, the Garden’s first
perennial was verified using high-quality digital images of the Garden’s 178 accessions of
Geranium. The Garden’s geraniums were verified by the widely recognized geranium expert in
the U.S., Ms. Robin Parer. Ms. Parer was previously President of the Hardy Geranium Society
and owner of Geraniaceae, a commercial nursery operation in California. The most recent
verifications are Solidago (Goldenrod) and Carex (Sedge).
The use of digital images is a superior means of documenting the collections compared to dry
herbarium vouchers (which can lose color as the flowers dry and age). This is the first known
effort of its kind in the U.S. and perhaps, the world. A valuable product from these Verification
Program efforts is the Verification Profile sheets created for each taxon. See Appendix II.
These are made available to the public and professionals through the Lenhardt Library and the
Internet.
14
Priorities need to be established and implemented as part of long-term verification
programming. Genotypic verification is a technology currently in use with much greater
accuracy than the older morphologic efforts. Genotypic verification is carried out in a
laboratory by means of DNA analyses. Volunteers in the Plant Collections Documentation
department are collecting DNA samples from ornamental plants in the collections. This DNA
bank will be useful in the future for identifying different genera in the collections.
Since the Garden lacks a horticultural taxonomist, curators have assumed the responsibility for
the accurate verification of the Garden’s collections. The following genera have been
photographically verified:
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2005 – Symphyotrichum
2006 – Schoenoplectus
2008 – Carex
2009 – Solidago
The following genera are planned for photographic verification:


2012 – Narcissus
2013 – Iris
To date, 311 woody taxa have been verified for viburnum (Viburnum), crabapple (Malus),
serviceberry (Amelanchier), dogwood (Cornus), spirea (Spiraea), and euonymus (Euonymus). There
are approximately 300 woody plant vouchers for verified plants held in the herbarium. In 1995
and 1996, Dr. William Hess, former taxonomist from The Morton Arboretum, verified 55 taxa
of Spiraea. In 2005, Dr. Edward Hasselkus determined 40 out of 64 Spiraea taxa to be true to
name. Thuja plicata (14 taxa) were verified by Dr. Hasselkus in October 2008. In 2010, David
Guthery verified at least one accession of every taxon of Amelanchier in the Garden’s collection.
Of the 106 accessions in the collections, 62 were surveyed.
D. Plant Exploration
The Garden’s Plant Exploration Program exists to expand the Garden’s collections either with
new plants collected from the wild (with known provenance), or collected from horticultural
sources from other countries. Whenever feasible, wild collections are made from the northern
part of a plant’s natural range, thereby bringing in cold-hardier plants from abroad which are
already in North American collections. The ultimate goal is to enrich the world’s storehouse of
plant material, the nation’s ornamental landscapes, and American scientific collections with new
plants from around the globe.
The Garden has participated in numerous collecting trips, usually through the Plant Collecting
Collaborative (PCC) or the North American China Plant Exploration Consortium (NACPEC).
These are conducted in conjunction with national scientific or academic institutions of other
countries. The Midwest Plant Collecting Collaborative was originally formed in 1992 and is now
15
a consortium of five institutions called the Plant Collecting Collaborative: Chicago Botanic
Garden, Missouri Botanical Garden, New York Botanical Garden, and the following two
arboreta: Morton and University of Minnesota. The purpose of the PCC is “to acquire
ornamental plants from around the world with similar climates that are well-suited to the upper
Midwest.” Past PCC trips include Central Siberia (1993), Russian Far East (1997), Republic of
Georgia, Southeastern United States (2000), Ozarks (2004), China (2007), and the Republic of
Georgia (2010). Garden staff participated on NACPEC expeditions to Xian, China (1996) and
Shanxi, China (2002), coordinated by NACPEC. Past and future PCC expeditions are outlined
in Appendix III. A total of 190 perennial taxa (2,334 plants) are currently recorded as having
been acquired from these previous expeditions.
The Woman’s Board sponsored a six-year effort to acquire new plants, called the Collections
2000 program, which targeted plants unknown in the U.S. from commercial sources in Europe
and Japan. This, too, has been a source of herbaceous plants -- 69 perennial taxa with a total of
785 plants have come in from this program.
Future trips will focus first on the Specialized Collections. These are of value to the Garden as a
repository of valuable germplasm, potential material for breeding, and as an accurate reference
when verified. Botanical institutions act as “Noah’s Arks” of living plants that are documented,
studied, cared for, and made available to others. They will be available if original populations in
the world are decimated by natural disasters or human activity, the need for research, or
potential for introduction. Expeditions require extensive planning and fieldwork that
documents each collection with herbarium vouchers, field notes, and photographs.
The Plant Evaluation Program evaluates some of the plants brought in from expeditions. The
best plants from the evaluations have been incorporated into the permanent collections, whereas
those that are poor performers or have shown a tendency for weediness have been destroyed.
The remainder of the plant taxa brought in through plant exploration trips have been
incorporated directly into the collections and have not undergone an equivalent evaluation, but
are reviewed for health annually. The evaluation of ornamental value in these wild-collected
specimens would prove valuable.
Given the limited growing space and changing focus of the plant evaluation program, the
collections may need to absorb a greater portion of the taxa brought in from future collecting
trips. The Collections staff will need to develop a mechanism to evaluate these plants for their
display value and potential weediness in the permanent collections.
While the United States has not signed the Convention on Biological Diversity (CBD), the
Chicago Botanic Garden honors the agreement in principle. Therefore, it is the responsibility of
the recipients of plants or propagules to abide by the CBD regulations as outlined by their
respective countries.
As expedition plants are grown from seed for inclusion in the collections, the potential exists for
superior horticultural forms to occur. The curatorial and horticultural staff will recommend
such plants to the plant introduction program for their review of value in potential commercial
introduction, and marketing.
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Care and Maintenance of the Collection
An important part of a collection is its health, accomplished by consistent and constant
maintenance. The Horticulture Department is responsible for the care of the herbaceous
perennial collections, including planting, pruning, fertilization, and pest control. They initiate
orders for and help determine, along with the Collections staff, which plants are added to the
collections. The curators collaborate with the horticultural staff to provide a Garden-wide
perspective when incorporating plants into the collections to avoid redundancy, provide
diversity from garden to garden, and advise on proper placement and care.
II.
Use of the Collection
A. Education
The Garden’s Living Collection is a vital component of education programs. The Garden staff
possesses a wealth of knowledge about the Collection, which they share in a variety of ways.
The Lenhardt Library of the Chicago Botanic Garden’s collections, some 32,000 books and
journals, serve as an invaluable resource on nomenclature, discovery, culture, and aesthetics of
herbaceous perennials in the living collections. The Library’s book collection has evolved in
tandem with the evolving plant collection at the Garden. In addition, the Library collects, and
makes available, journals of specialized plant societies, such as the Daffodil Journal of the American
Daffodil Society, the Daffodil and Tulip Yearbook, the Bulletin of the American Iris Society, and the Daylily
Journal of the American Hemerocallis Society. The Library also collects authoritative checklists and
references to these plants, such as the Alphabetical Iris Checklist of the American Iris Society, the
International Daffodil Register and Checklist of the Royal Horticultural Society, and A Guide to Species Iris by
the British Iris Society. The Library maintains an extensive collection of nursery and seed catalogs
(numbering in the thousands), as well as diverse periodicals (altogether some 3,000 titles). These
publications provide both historical and up-to-date information on varieties and sources that
ultimately will enrich the Garden’s collections.
Through its programs, the School makes it possible for diverse professional and amateur
audiences to learn to identify, grow, maintain, and enjoy perennials. Education staff who use the
collections are asked to provide suggestions for determining collections content. The curators
will interact with teachers in the Botanic Garden to make sure the collection serves their needs
and will teach in the School.
B. Research
Research on perennial plants within the collections may focus directly on an individual plant, a
taxon, or on groups of related plants.
The permanent collections have benefited from the Garden’s Plant Evaluation Program. As the
program completes its research on any given target genus, the best plants are transferred to the
permanent collections. In turn, germplasm from plant hunting expeditions has been used in the
Plant Breeding program.
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The Garden evaluates many of the plants collected abroad through its plant exploration program
before they enter the permanent plant collections throughout the Garden. The Garden’s Collection
Policy states that any plant “which has the potential to threaten the genetic diversity of local native
populations, [shows] overly aggressive behavior (weediness), or [has] the ability to introduce pests or
diseases will be screened and evaluated before being accepted into the Collection.” It should be
noted that most exotic or non-native plants are not invasive and greatly enrich our lives and
landscapes.
Areas for possible collaboration with the Ornamental Plant Research Programs and other
opportunities with perennials in the permanent collections include:
 Potential Invasiveness Risk Assessment Trials – studies have been and will continue to be
conducted to determine the propensity for invasiveness of plants new to cultivation in the
Midwestern United States, per the Garden’s Invasive Species Policy. There is a need to
develop a decision tree for estimating the invasiveness of perennials in the U.S. The
previously developed models have been based on woody taxa. There is the opportunity to
develop a perennial key. This effort would benefit the Garden, the Midwest, and the U.S.
research on plant invasiveness. Determining what makes a plant invasive and whether
invasiveness can be predicted short of actually putting plants in a natural habitat is still in its
infancy. The approach may be to take features of the woody plant models, adapt them for
perennial plants, include other biological parameters, and then begin to test the accuracy of
the model with actual research. As the number of taxa studied increases, the model would
be developed and modified as needed.
 Plant Breeding Program – the breeding program is currently developing new perennial plant
hybrids from several genera, including one Specialized Collection, Symphyotrichum (aster). As
the program has developed new hybrid perennial plants, they are included in the permanent
collections, enhancing collections diversity. Breeding stock and wild-collected plants have
also been shared with collections. In the future, the breeding program could conduct
breeding on other Specialty Collections taxa.
 Plant Introduction Program – as more perennial plants from the plant collecting trips are
included in the collections, they may be possibilities for additional Chicagoland Grows
introductions. Development of the Specialized Collections could also further collaborative
breeding projects between Research and Collections staff.
 Longevity studies of herbaceous perennials – literature only anecdotally states the longevity
of most perennials; actual data in the Garden’s plant records can be used to document this
data.
 Sometimes, the most important information about plants comes from anecdotal
observations made on the collections.
The curators will conduct and coordinate plant collection-based research that will focus on
evaluating the existing plants for their long-term value in landscape situations and as ornamental
plants. Plants will be studied for their adaptability to both biotic and abiotic stresses present at
the Garden and in the region. These projects will often span multiple years. Currently, an
informal evaluation of resistance to foliar blight among Aesculus taxa is being conducted. New
taxa were added to the collections in 2011 and these will be included in this evaluation in
subsequent years.
18
In 2011, the Curator of Woody Plants, in collaboration with the Manager of the Plant
Evaluation Program, initiated comparative trial of witch hazels. Witch hazels (Hamamelis)
includes native, non-native, and hybrids that are greatly valued in landscapes for their fall or late
winter flowers. Some taxa have performed very well at the Garden and in the region, while
others languish in the landscape. To determine which taxa are best suited for this region, 35
commercially available taxa were acquired for this study. Three plants of each taxa were planted
in the Lavin Evaluation Garden and at least one individual of each was added to the Garden’s
general plant collections.
Similar collaborative research projects have been planned. This on-going effort provides the
opportunity to: 1) add new taxa to the Garden’s collection; 2) conduct collections-based
research; and 3) display and disseminate information on the best plants for the Chicago region.
The next group for formal evaluation and collections diversification will be Hydrangea serrata,
starting in 2012. Candidate groups for the future include Cornus mas, Viburnum, and Fothergilla.
C. The Visitor
Visitor programs strengthen the connection between the collections and the visiting public
through a number of program formats including interpretative signs and brochures, volunteer
docents in select Garden areas, and gallery exhibits. The Garden hosts numerous plant society
shows and has lectures and workshops for the general public in association with these events.
These shows (lily, iris, daffodil, hosta, and daylily) are open to the public and are well received by
the public. Society members bring their advice and experience on new plant selections and
cultural techniques to the Garden. The Garden’s Manager of Plant Sales and Flower Shows is
committed to strengthening the ties between plant sales and the plant collections and
horticulture staff.
One of the greatest challenges for public gardens, and especially the Chicago Botanic Garden,
which has all its genera mixed throughout display gardens, is to improve accessibility of the
collections to the public. The Garden has received an IMLS grant to establish an interactive
display that would permit visitors to find plants in the Garden. This would allow the public to
locate, view and study perennials for: landscape use, School curricula, plant sales, location of
donor plants, and could enhance the learning experience for the visitor in the Garden. The
program will also contain information about the plants, images, and will be available on the
Garden’s website. This effort is being headed up by the Communications Department.
D. Public Communication
The Garden’s public relations team provides opportunities for the curators to share their
expertise with the public. The curators will work with the Garden’s Public Relations team and
Publications staff as the Garden’s authorities on plants. The Collections Department also
disseminates information through articles, books (authorship and reviews), teaching Illinois
Institute of Technology college courses, the Ornamental Plant Materials Certificate (OPC)
program, the Regenstein School of the Chicago Botanic Garden classes, College First and
Science First, volunteers, Keep Growing magazine, Plant Information (Fact Sheets, staff
questions), signage (passive interpretation) and symposia.
19
The results of observations and studies on the collection will be shared through articles and the
Joseph Regenstein, Jr. School of the Chicago Botanic Garden’s Certificate Programs and
Symposia.
The Botanic Garden has an excellent national reputation for its educational curriculum. It
furthers the value of the woody plant collection to have them actively used by students and
teachers. This includes academic institutions such as the Universities of Wisconsin and Illinois,
Northwestern University, Illinois Institute of Technology, and 2-year colleges. The Joseph
Regenstein, Jr. School of the Chicago Botanic Garden uses the woody plant collection for
certificate classes on evergreen and deciduous trees and shrubs.
The curators use several media – lectures, symposia, articles, and the Internet to share expertise
gained by studying the collection. The curators teach courses for the Master of Landscape
Architecture program at the Illinois Institute of Technology.
The Woody Plant Curator also serves on the Chicago Trees Initiative task force and, working
with City of Chicago departments and other partner agencies, will develop a list of the best trees
for planting in the urban landscape.
CONCLUSION
The Garden’s plant collections are not only beautiful, but are museum objects and provide working
materials within a living laboratory, a complete resource for scientific study, a storehouse of rare
germplasm, a warehouse for plant breeding, a source for plant introductions and a teaching tool for
professionals and the general public. Over the last 40 years, the Chicago Botanic Garden has
evolved into a major museum with a designed landscape of over 2.5 million documented plants.
Great opportunities exist to increase the scope, value and effectiveness of the Garden’s collection.
To extend its mission, the Garden must continue to invest in new plants to replace senescing older
plants to keep the Collection up-to-date. The curators must leverage the Garden’s relationship with
other botanical institutions and commercial producers to obtain collection donations to the Garden.
It must also sustain a professional staff that provide the needed visionary thinking, skilled
management, and expertise in their various fields.
By building the Specialized Collections, the Garden has the opportunity to further its stewardship
responsibility as a museum, member of the botanic garden community, and as a liaison and
contributor to the public and private sectors.
This Paper makes the following recommendations:
 Build the world’s best public plant collection, focusing on Specialized Collections.
 Increase depth (number of taxa within a genus) and breadth (number of taxa) within the
collections and reduce redundancy.
 Improve procedures for capturing plant data in a timely way when plants are brought into the
Garden, are moved, or die.
 Meet with Education annually for their input on collections development.
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Further elevate the reputation of the Chicago Botanic Garden through peer-reviewed and
popular articles written by the curators.
Evaluate existing plantings and determine candidates for removal because of decline, infestations
of insects or infections from disease, redundancy, or invasiveness.
Systematically verify the plants at the Garden to improve the integrity of the plant collection and
increase its value in education.
Collaborate with the Manager, Plant Evaluation Program to acquire new taxa for the Garden’s
collection and conduct formal evaluation trials. Data collected from the Tree Health
Assessment will be utilized to conduct climate change modeling of selected tree species to
predict which species are potentially best suited to adapt to a changing environment.
Continue to teach in the Master of Landscape Architecture program at the Illinois Institute of
Technology and the Joseph Regenstein, Jr. School of the Chicago Botanic Garden. The Woody
Plant Curator will be responsible for co-authoring future Plant Evaluation Notes that focus on
woody plants.
Expand the Collections Specialist position to an Assistant Curator of Ornamental Plants to
enhance the curation of the woody plant collection for its scientific value and use by garden
visitors, scientists, green industry professionals, and educators.
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Appendix I
CRITERIA FOR GENUS SELECTION
FOR SPECIALIZED COLLECTIONS
1. The genus provides an opportunity to address research issues, particularly applied research,
which the Garden can undertake.
2. The Garden has sufficient staff, space, equipment, and financial support to add the taxon to the
collection.
3. There is sufficient curatorial support (dedicated staff resources) to acquire, develop, study, and
disseminate the findings associated with a plant group.
4. Value should exist in terms of conservation, natural areas management, advance knowledge, and
literature.
5. The genus must be appropriate for the growing conditions of the Midwest (drought and
moisture tolerant, adaptable to soils with high pH’s and high clay content, etc.).
6. It must complement other Garden programs such as education, plant development,
conservation science, and plant exploration.
7. It must fulfill a landscape need from a holistic perspective for season-long aesthetic interest,
growth form, and culture.
8. It should benefit the North American Plant Collections Consortium program, which coordinates
plant collection holdings in North America.
9. It must be relevant to the Garden’s visitors and constituents.
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Appendix II
23
Appendix III
PAST PLANT COLLECTING COLLABORATIVE (PCC) EXPEDITIONS
1993
Russia, Central Siberia
1996
Xian, China (NACPEC)
1997
Russia, Far East
2000
Republic of Georgia (FSU)
2000
North Carolina & Southeastern U.S.
2001
China (scheduled – cancelled due to 9/11)
2002
Shanxi, China (NACPEC)
2004
Ozarks
2007
China
2007
Siberia (NACPEC)
2009
Caucasus, Republic of Georgia (cancelled)
2010
Caucasus, Republic of Georgia
POSSIBLE FUTURE PCC EXPEDITIONS
2012
Caucasus, Republic of Georgia
2014
Hokkaido, Japan
2016
South Korea
2018
Kamchatka, Russia
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Appendix IV
Components for Establishment of Specialized Collections
1. Conduct a literature search to resolve synonymy, determine taxa to be collected, and enter data.
2. Complete numerous data fields to establish a database for planning purposes and as a resource
for others (e.g., flower color, hardiness, height, current numbers, locations, etc.).
3. Evaluate the data; detect redundant taxa for replacements and determine and assess acquisition
issues (such as quarantines, documented wild origin, international regulations, etc.).
4. Using the database, determine the plants appropriate for acquisition that are available from
commercial sources and identify reliable sources, confirm availability, request taxa, and pursue
donations.
5. Research nativities of botanical species; identify nativities, make and correspond with field
contacts.
6. Perform a Weed Risk Assessment; conduct theoretical testing to estimate potential invasive
characteristics.
7. Plan and develop plant-collecting expeditions.
8. Grow acquired plants to flowering size.
9. Planting with post-planting care secured.
10. Verification
a. Maintain at least one herbarium specimen for each taxon (accession).
b. Provide photographic verification for horticultural traits; document collections with digital
images:
i. Create a profile sheet of six images that thoroughly depicts the taxon;
ii. Designate one photo of the plant’s habit, one close-up photo of the inflorescence, and
one photo of a leaf/or other distinguishing characteristic of the plant for the Collections
web page.
11. Evaluate the plant’s performance.
12. Perform periodic inventories.
25