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Species Rating Guide

Species Ratings & Appraisal Factors for Illinois

For use by qualified professionals in conjunction with the Nineth Edition of the Guide for Plant Appraisal published by the International Society of Arboriculture


The Illinois Arborist Association Tree Appraisal Committee that worked very hard to develop the information in this booklet consisted of:
  • Bill Bolt (Chair), Consulting Arborist

  • Stan Holat, Autumn Tree Care Experts

  • Terry Cichocki, Village of Northbrook

  • John Kirchner, City of Chicago

Special thanks also to Galen Gates at the Chicago Botanic Garden and George Ware at the Morton Arboretum for their assistance in updating the species ratings, and to our colleagues in adjacent states who form a regional committee, which assures continuity across state lines.

NOTE: The information given in this booklet will be reviewed and updated at appropriate intervals. If a change is made, it will be published by the Illinois Arborist Association, a Chapter of the ISA, in a method determined by the Board of Directors. If you are not sure of the latest information, call the Chapter office at (877) 617-8887.

INTRODUCTION

The Guide for Plant Appraisal (9th Edition) specifies that "for these appraisal methods to be effective, relatively easy to use, and widely accepted in a region, a group of horticultural professionals should be the ones to determine, keep updated and publish"

  • Species ratings

  • Largest commonly available transplantable tree

  • Average cost of tree replacement, and

  • Cost per unit trunk area.

Species ratings are based only on species characteristics, without regard to condition or location. Factors considered were environmental adaptability, biological traits (i.e. growth rate, pest resistance), maintenance requirement and aesthetic characteristics. Condition and location factors related to these species characteristics must be considered carefully. For example, pin oak has limited environmental adaptability with regard to soil type, and this contributes to its 70 percent rating. However, when planted in alkaline soil, the site component of the location factor would have to be rated low. Condition of the tree might be poor as well.

The information on this website should be accurate for most situations. However, individual situations may be unusual. Occasionally, characteristics of an individual tree or cultivars may be superior. Microclimate variation can occur. The professionals using this booklet in conjunction with the Guide for Plant Appraisal may occasionally find that their own judgment calls for alteration of this generalized information.

Illinois is nearly 400 miles long from north to south. The climate for growing trees varies considerably within the state. The USDA Plant Hardiness Zone Map was used to divide the state into three regions, corresponding to hardiness zones 5a (north), 5b (central), and 6a (south). See USDA Miscellaneous Publication Number 1475 for more details on hardiness zones.

There are essentially two categories of information in the Species Ratings Guide & Appraisal Factors for Illinois and this sometimes leads to confusion.  Since the initial publication in 1994 there have been two updates to the Appraisal Factors; in 2001 and 2005.  The methods for determining these factors are set forth in the Guide for Plant Appraisal and are the factors are updated periodically to reflect current market conditions.  The original Species Rating Percentages for Illinois have not changed.

A survey of Illinois Green Industries is used to gather the data for the Appraisal Factors which include the largest commonly available transplantable sized tree, the installed and guaranteed cost of the largest commonly available transplantable tree, and the basic cost or unit tree cost per unit of trunk area ($ per square inch).  These values are used along with the Species Rating Percentages in the Trunk Formula Method of plant appraisal.  The Appraisal factors (except the unit tree cost) and the Species Rating Percentages are also used in the Replacement Cost Method outlined in the 9th Edition of the Guide for Plant Appraisal.

It is important to understand that the published Appraisal Factors and Species Rating Percentages are generally agreed upon values that can be used to calculate appraised values for landscape plants.  Appraisers can and often do calculate the Appraisal Factors based on their own research which may be more precise in specific cases.  The Guide for Plant Appraisal incorporates some flexibility in how the Appraisal Factors are determined and the decisions made by the committee may not reflect local conditions.  It is also legitimate for an appraiser to substitute his or her own Species Rating Percentage(s) based on local conditions and expertise of the appraiser.  If substitute values are used by an appraiser, he or she should expect to be called upon to explain how they were determined and to justify them if the appraisal is challenged.

  Click here for a map of the regions

Name

 

North

Central

South

Abies concolor, White or Concolor Fir

 

80

80

80

Acer campestre, Hedge or Field Maple

 

70

70

70

Acer ´freemanii, Freeman Maple

 

70

70

70

Acer ginnala, Amur Maple

 

70

70

70

Acer griseum, Paperbark Maple

 

70

70

70

Acer miyabei, Miyabe Maple

 

80

80

80

Acer negundo, Boxelder

Male

40

40

40

Acer negundo, Boxelder

Female

20

20

20

Acer nigrum, Black Maple

 

80

80

80

Acer palmatum, Japanese Maple

 

50

70

70

Acer platanoides, Norway Maple

Species

60

60

60

Acer platanoides, Norway Maple

Improved Cultivars

70

70

70

Acer pseudoplatanus, Sycamore Maple

 

50

70

70

Acer rubrum, Red or Swamp Maple

Species

60

60

60

Acer rubrum, Red or Swamp Maple

Improved Cultivars

70

70

70

Acer saccharinum, Silver Maple

Species

50

50

50

Acer saccharinum, Silver Maple

Improved Cultivars

50

50

50

Acer saccharum, Sugar Maple

Species

80

80

80

Acer saccharum, Sugar Maple

Improved Cultivars

90

90

90

Acer tataricum, Tartarian Maple

 

70

70

70

Acer triflorum, Three-Flowered Maple

 

80

80

80

Acer truncatum, Purpleblow Maple

 

70

70

70

Aesculus ´carnea, Red Horsechestnut

 

60

70

70

Aesculus glabra, Ohio or Fetid Buckeye

 

70

60

60

Aesculus hippocastanum, Common Horsechestnut

 

60

60

60

Aesculus octandra (flava), Yellow Buckeye

 

70

60

60

Aesculus pavia, Red Buckeye

 

70

70

70

Ailanthus altissima, Tree of Heaven

Male

40

40

40

Ailanthus altissima, Tree of Heaven

Female

20

20

20

Albizia julibrissin, Mimosa or Silk Tree

 

0

20

20

Alnus glutinosa, European Black Alder

 

70

70

70

Alnus incana, White Alder

 

70

70

70

Alnus rugosa, Speckled Alder

 

70

70

70

Amelanchier, Serviceberry

 

70

70

70

Asimina triloba, Common Pawpaw

 

50

50

50

Betula alleghaniensis (lutea), Yellow Birch

 

50

50

50

Name

 

North

Central

South

Betula lenta, Sweet Birch

 

60

50

50

Betula nigra, River or Red Birch

 

70

70

70

Betula papyrifera, Paper Birch

 

40

40

40

Betula pendula, European White Birch

 

30

20

20

Betula platyphylla 'Whitespire Senior', Japanese Whitespire Birch

 

60

50

50

Betula populifolia, Gray Birch

 

50

40

40

CarPinus betulus, European Hornbeam

 

70

70

60

CarPinus caroliniana, American Hornbeam (Blue Beech)

 

70

70

60

Carya cordiformis, Bitternut Hickory

 

70

70

70

Carya illinoensis, Pecan

 

60

60

60

Carya ovata, Shagbark Hickory

 

70

70

70

Carya tomentosa, Mockernut Hickory

 

60

70

70

Castanea dentata, American Chestnut

 

20

20

20

Castanea mollissima, Chinese Chestnut

 

60

60

60

Catalpa bignonioides, Southern Catalpa

 

40

40

40

Catalpa ovata, Chinese Catalpa

 

50

40

40

Catalpa speciosa, Northern or Western Catalpa

 

50

40

40

Celtis laevigata, Sugar Hackberry

 

30

80

80

Celtis occidentalis, Common Hackberry

 

80

80

80

Cercidiphyllum japonicum, Katsura Tree

 

70

70

70

Cercis canadensis, Redbud

 

70

80

80

Chionanthus virginicus, Fringetree

 

70

60

60

Cladrastis lutea (kentukea), Yellowwood

 

60

60

60

Cornus alternifolia, Pagoda Dogwood

 

70

70

70

Cornus florida, Flowering Dogwood

 

30

60

70

Cornus kousa, Kousa Dogwood

 

50

70

70

Cornus mas, CornelianCherry Dogwood

 

80

70

70

Cornus officinalis, Japanese Cornel Dogwood

 

70

70

70

Corylus colurna, Turkish Filbert

 

80

80

80

Cotinus coggygria, Common Smoke Tree

 

60

70

70

Cotinus obovatus, American Smoke Tree

 

70

70

70

Crataegus crus-galli, Cockspur Hawthorn

 

80

80

80

Crataegus laevigata, English Hawthorn

 

40

40

40

Crataegus mollis, Downy Hawthorn

 

50

50

50

Crataegus phaenopyrum, WAshington Hawthorn

 

70

70

60

Crataegus punctata, Dotted Hawthorn

 

50

50

50

Crataegus ´lavallei, Lavalle Hawthorn

 

60

60

60

Crataegus 'Vaughn', Vaughn Hawthorn

 

60

60

60

Crataegus viridis 'Winter King', Winter King Hawthorn

 

70

70

70

Diospyros virginiana, Common Persimmon

Male

50

70

70

Name

 

North

Central

South

Diospyros virginiana, Common Persimmon

Female

30

50

50

Elaeagnus angustifolia, Russian-Olive

 

40

40

40

Eucommia ulmoides, Hardy Rubber Tree

 

50

70

70

Fagus grandifolia, American Beech

 

60

80

80

Fagus sylvatica, European Beech

 

70

70

70

Fraxinus americana, White Ash

Species

60

60

60

Fraxinus americana, White Ash

Improved Cultivars

70

70

70

Fraxinus excelsior, European Ash

 

60

60

60

Fraxinus pennsylvanica, Green Ash

Species

70

70

70

Fraxinus pennsylvanica, Green Ash

Improved Cultivars

80

80

80

Fraxinus quadrangulata, Blue Ash

 

70

70

70

Ginkgo biloba, Ginkgo

Male

90

90

90

Ginkgo biloba, Ginkgo

Female

60

60

60

Gleditsia triacanthos, Honeylocust

 

30

30

30

Gleditsia triacanthos f. inermis, Thornless Honeylocust

 

80

70

70

Gymnocladus dioica, Kentucky Coffee tree

Male

80

80

80

Gymnocladus dioica, Kentucky Coffee tree

Female

60

60

60

Halesia carolina, Carolina Silverbell

 

70

70

70

Ilex opaca, American Holly

 

40

70

80

Juglans cinerea, Butternut

 

30

30

30

Juglans nigra, Black Walnut

 

50

40

40

Juniperus chinensis, Chinese Juniper

 

80

60

60

Juniperus virginiana, Eastern Red Cedar

 

70

50

50

Koelreuteria paniculata, Golden Raintree

 

50

70

80

Larix decidua, European Larch

 

60

60

60

Larix kaempferi, Japanese Larch

 

60

60

60

Larix laricina, American Larch

 

50

50

50

Liquidambar styraciflua, Sweetgum

 

50

60

70

Liriodendron tulipifera, Tuliptree

 

60

80

80

Maclura pomifera, Osage-Orange

Male

60

60

60

Maclura pomifera, Osage-Orange

Female

40

40

40

Magnolia acuminata, Cucumbertree Magnolia

 

70

70

70

Magnolia grandiflora, Southern Magnolia

 

0

50

80

Magnolia kobus, kobus Magnolia

 

50

60

60

Magnolia ´loebneri, Loebner Magnolia

Improved Cultivars

60

70

70

Magnolia ´soulangiana, Saucer Magnolia

 

60

70

70

Magnolia virginiana, Sweetbay Magnolia

 

40

60

70

Malus, Crabapple

Superior Cultivars

80

80

80


 

Name

 

North

Central

South

Malus, Crabapple

Inferior Cultivars

60

60

60

Metasequoia glyptostroboides, Dawn Redwood

 

50

60

60

Morus alba, White Mulberry

Male

50

50

50

Morus alba, White Mulberry

Female

30

30

30

Morus rubra, Red Mulberry

Male

50

50

50

Morus rubra, Red Mulberry

Female

30

30

30

Nyssa sylvatica, Sourgum (Black Tupelo)

 

70

80

80

Ostrya virginiana, Ironwood (Hophornbeam)

 

80

80

80

Oxydendrum arboreum, Sourwood

 

30

60

80

Paulownia tomentosa, Paulownia (Princess Tree)

 

30

40

50

Phellodendron amurense, Amur corktree

Male

70

80

80

Phellodendron amurense, Amur corktree

Female

50

60

60

Picea abies, Norway Spruce

 

70

70

70

Picea engElmannii, Engelmann Spruce

 

60

60

60

Picea glauca, White Spruce

 

70

70

70

Picea glauca var. Densata, Black Hills Spruce

 

70

70

70

Picea omorika, Serbian Spruce

 

70

70

70

Picea pungens, Colorado Spruce

 

70

70

70

Pinus banksiana, Jack Pine

 

50

40

40

Pinus bungeana, Lacebark Pine

 

70

70

70

Pinus cembra, Swiss Stone Pine

 

70

70

70

Pinus echinata, Short Leaf Pine

 

10

50

60

Pinus flexilis, Limber Pine

 

70

70

70

Pinus nigra, Austrian or Black Pine

 

50

40

40

Pinus peuce, Balkan or Macedonian Pine

 

70

70

70

Pinus ponderosa, Ponderosa Pine

 

60

60

60

Pinus resinosa, Red Pine

 

50

50

50

Pinus strobiformis, Southwestern White Pine

 

70

70

70

Pinus strobus, Eastern White Pine

 

70

70

70

Pinus sylvestris, Scotch Pine

 

40

40

40

Pinus wallichiana, Himalayan White Pine

 

70

70

70

Platanus ´acerifolia, London Planetree

 

60

60

60

Platanus occidentalis, Sycamore

 

50

60

60

Populus alba, White or Silver Poplar

 

30

30

30

Populus deltoides, Cottonwood

Male

50

50

50

Populus deltoides, Cottonwood

Female

30

30

30

Populus euroamericana, Hybrid Poplar

 

50

50

50

Populus grandidentata, Bigtooth Aspen

 

50

50

50

Populus nigra 'Italica', Lombardy Poplar

 

20

20

20

Populus tremuloides, Quaking Aspen

 

50

50

50

Name

 

North

Central

South

Prunus americana, Wild Plum

 

50

50

50

Prunus armeniaca var. mandshurica, Manchurian Apricot

 

50

50

50

Prunus avium, Sweet Cherry

 

40

40

40

Prunus cerasifera, Purple Leaf Plum

 

40

40

40

Prunus maackii, Amur Choke Cherry

 

60

60

50

Prunus padus, European Bird Cherry

 

40

40

40

Prunus pensylvanica, Pin Cherry

 

40

40

40

Prunus persica, Common Peach

 

30

40

40

Prunus sargentii, Sargent Cherry

 

70

70

70

Prunus serotina, Black Cherry

 

50

50

50

Prunus serrulata, Japanese Flowering Cherry

 

30

40

40

Prunus subhirtella var. pendula, Weeping Cherry

 

30

40

40

Prunus virginiana, Choke Cherry

 

40

40

40

Psuedotsuga menziesii, Douglasfir

 

80

80

80

Pyrus calleryana, Callery Pear

Superior Cultivars

80

80

80

Pyrus calleryana, Callery Pear

Inferior Cultivars

60

60

60

Quercus alba, White Oak

 

90

90

90

Quercus acutissima, Sawtooth Oak

 

60

70

70

Quercus bicolor, Swamp White Oak

 

80

80

80

Quercus coccinea, Scarlet Oak

 

70

70

80

Quercus ellipsoidalis, Hill's or Northern Pin Oak

 

70

70

70

Quercus falcata, Southern Red Oak

 

30

50

60

Quercus falcata var. pagodaefolia, Cherrybark Oak

 

30

50

70

Quercus imbricaria, Shingle Oak

 

70

70

70

Quercus macrocarpa, Bur Oak

 

90

90

90

Quercus marilandica, BlackJack Oak

 

30

40

50

Quercus michauxii, Swamp Chestnut Oak

 

40

70

70

Quercus muehlenbergii, Chinqua Pin Oak

 

80

80

80

Quercus palustris, Pin or Swamp Oak

 

70

70

70

Quercus phellos, Willow Oak

 

30

50

70

Quercus prinus, Chestnut Oak

 

70

70

70

Quercus robur, English Oak

 

60

70

80

Quercus rubra, Red Oak

 

70

70

70

Quercus shumardii, Shumard Oak

 

60

70

70

Quercus stellata, Post Oak

 

30

50

60

Quercus velutina, Black Oak

 

60

60

60

Rhamnus cathartica, Common Buckthorn

Male

40

40

40

Rhamnus cathartica, Common Buckthorn

Female

20

20

20

Robinia pseudoacacia, Black Locust

 

40

40

40

Name

 

North

Central

South

Salix alba 'Tristis', Weeping Willow

 

40

40

40

Salix matsudana 'Tortuosa', Corkscrew Willow

 

30

30

30

Salix nigra, Black Willow

 

40

40

40

Sassafras albidum, Common Sassafras

 

60

70

70

Sophora japonica, Japanese Pagoda Tree

 

50

60

70

Sorbus americana, American Mountain Ash

 

40

40

40

Sorbus alnifolia, Korean Mountain Ash

 

50

50

50

Sorbus aucuparia, European Mountain Ash

 

50

50

50

Syringa pekinensis, Peking Lilac

 

70

70

70

Syringa reticulata, Japanese Tree Lilac

 

70

70

70

Taxodium distichum, Baldcypress

 

80

90

90

Thuja occidentalis, White Cedar Arborvitae

 

80

70

70

Thuja orientalis, Oriental Arborvitae

 

50

60

60

Tilia americana, American (Basswood) Linden

 

70

70

70

Tilia cordata, Little Leaf Linden

 

70

70

70

Tilia ´euchlora 'Redmond', Redmond Linden

 

80

80

80

Tilia heterophylla, Bee Tree Linden

 

70

70

70

Tilia platyphyllos, Big Leaf Linden

 

60

70

70

Tilia tomentosa, Silver Linden

 

60

70

70

Tsuga canadensis, Canadian hemlock

 

80

80

80

Ulmus, Hybrid Elm

 

70

70

70

Ulmus americana, American Elm

 

20

20

20

Ulmus carPinifolia, English Elm

 

30

30

30

Ulmus parvifolia, Chinese or Lacebark Elm

 

60

70

70

Ulmus pumila, Siberian Elm

 

40

40

40

Ulmus rubra, Slippery or Red Elm

 

20

20

20

Ulmus thomasii, Rock Elm

 

30

30

30

Viburnum prunifolium, Blackhaw Viburnum

 

70

70

70

Viburnum sieboldii, Siebold Viburnum

 

50

60

60

Zelkova serrata, Zelkova

 

40

50

60

 

 


Illinois Appraisal Factors

 

 

Economic conditions and the price of nursery stock vary across the state. The state has been divided into regions that reflect these differences.

 

 

REPLACEMENT TREE SIZE

 

The largest commonly-available transplantable sized tree, measured at a point 6 inches above the ground, has been determined for all regions of the state. This information is based on a survey of the available nursery material.

 

 

1994

2001

2005

200*

Region A

3 ½

3

 4 inch

 

Region B

3

3 ½

 3 inch

 

Region C

3 ½

3*

 

 

Region D

2 ½

2 ½*

 

 

 

 

INSTALLED TREE COST

 

This is the average cost to purchase and install the largest commonly-available transplantable tree of high quality species. The cost includes transportation to the planting site, site preparation, planting, guarantee, and profit.

 

 

1994

2001

2005

200*

Region A

$570

$513

 $787

 

Region B

$310

$548

 $527

 

Region C

$340

$393*

 

 

Region D

$150

$349*

 

 

 

 

UNIT TREE COST

 

This is the cost per square inch of trunk area (cross section) to be used when determining total tree value. Based on a survey of largest commonly available transplantable sized nursery stock of high quality species at regional nurseries, the Illinois Chapter has set this value at:

 

 

1994

2001

2005

200*

Region A

$36/sq. in.

$47/sq. in.

 $71/sq. in.

 

Region B

$22/sq. in.

$42/sq. in.

 $69/sq. in.

 

Region C

$18/sq. in.

$38/sq. in.**

 

 

Region D

$15/sq. in.

$45/sq. in.**

 

 

 

* Use these columns for future revisions

** Based on limited data, appraiser is advised to gather additional local data