Tolerance of Trees and Shrubs to Salts in Soil
Tolerance of Trees to Salts in Soil
E = evergreen; N = native to Maine
| Trees That Tolerate High Soil Salt Levels: | |
|---|---|
| Aesculus hippocastanum | Common Horsechestnut |
| Amelanchier canadensis N | Canadian Serviceberry |
| Crataegus crus-galli N | Cockspur Hawthorn |
| Gleditsia triacanthos | Honeylocust |
| Pinus nigra E | Austrian Pine |
| Quercus alba N | White Oak |
| Quercus rubra N | Red Oak |
| Syringa reticulata | Japanese Tree Lilac |
| Trees That Tolerate Moderate Soil Salt Levels: | |
| Betula alleghaniensis N | Yellow Birch |
| Betula lenta N | Sweet Birch |
| Betula papyrifera N | Paper Birch |
| Betula populifolia N | Gray Birch |
| Celtis occidentalis | Hackberry |
| Fraxinus americana N | White Ash |
| Fraxinus pennsylvanica N | Green Ash |
| Ginkgo biloba | Maidenhair Tree |
| Thuja occidentalis E, N | Arborvitae; White Cedar |
| Trees That Tolerate Somewhat Elevated Soil Salt Levels: | |
| Malus hybrids | Apple, Crabapple |
| Picea abies E | Norway Spruce |
| Pinus strobus E, N | Eastern White Pine |
| Quercus palustris | Pin Oak |
| Trees That Are Intolerant of Elevated Soil Salts: | |
| Abies balsamea E, N | Balsam Fir |
| Acer rubrum N | Red Maple |
| Acer saccharum N | Sugar Maple |
| Amelanchier species (some N) | Shadbush |
| Carpinus caroliniana N | Ironwood |
| Cercis canadensis | Eastern Redbud |
| Pinus resinosa E, N | Red Pine |
| Sorbus aucuparia | European Mountainash |
| Tilia americana N | Basswood |
| Tilia cordata | Litteleaf Linden |
| Tsuga canadensis E, N | Canada Hemlock |
Tolerance of Shrubs to Salts in Soil
E = evergreen; N = native to Maine
| Shrubs That Tolerate High Soil Salt Levels: | |
|---|---|
| Caragana arborescens | Siberian Peashrub |
| Dasiphora (Potentilla) fruticosa N | Potentilla |
| Elaeagnus commutata | Silverberry |
| Euonymus japonica | Spindle Tree |
| Juniperus chinensis ‘Pfitzeriana’ E | Pfitzer Juniper |
| Rhus typhina N | Staghorn Sumac |
| Shepherdia canadensis N | Buffaloberry |
| Spiraea x vanhouttei | Vanhoutte Spirea |
| Symphoricarpos albus | Snowberry |
| Syringa vulgaris | Common Lilac |
| Shrubs That Tolerate Moderate Soil Salt Levels: | |
| Buxus microphylla E | Common Boxwood |
| Juniperus communis E, N | Common Juniper |
| Philadelphus coronarius | Mockorange |
| Rhus glabra N | Smooth Sumac |
| Shrubs That Tolerate Somewhat Elevated Soil Salt Levels: | |
| Chaenomeles speciosa | Floweringquince |
| Viburnum opulus | European Cranberrybush Viburnum |
| Shrubs That Are Intolerant of Elevated Soil Salts: | |
| Cornus racemosa N | Gray Dogwood |
| Cornus sericea N | Redosier |
About Salt Levels in Soil
Soil salt is measured by electrical conductivity (mmho/cm). Higher salt levels produce higher readings. If soil can be leached (that is, if it is in raised beds or containers), the amount of water needed to reduce salts to levels appropriate for most plants is:
| Salt level determined by soil test: | Water needed to leach: |
|---|---|
| 2.0 – 4.0 mmho/cm | 3″ water |
| 4.1 – 6.0 mmho/cm | 6″ water |
| 6.1 – 8.0 mmho/cm | 8″ water |
| 8.1 – 10.0 mmho/cm | 10″ water |
| 10.1 – 15.0 mmho/cm | 12″ water |
| over 15.0 mmho/cm | not practical |
From the GardenPro Answer Book; revised and updated by Lois Berg Stack, Ornamental Horticulture Specialist, University of Maine Cooperative Extension.