Planning tips and Shrubs Characteristic and demands

960 961 that need light 28

Plants that need plenty of light are often also pioneer plants, i.e. they are the first to settle on fallow land. The older they get, the less they tolerate any type of shade. They initially try to grow into the light when they are in the shade. But if shade-tolerant, more dominant plants (even large shrubs) come too close for long periods, they lose their and then die. Plants that form runners, such as Rhus typhina, try to get out of the shade with increased production of runners. And the following should be kept in mind: the poorer the location, for instance dry soil that is not nutritious, the more light is needed.

Note: All varieties that at least tolerate shade when young or still come to terms with shady areas when old have been left out.

1. Deciduous trees Genus/species/variety Reaction to shade

Acer cappadocicum...... crooked stem Acer freemanii ...... crooked stem Acer ginnala...... short-lived, crooked habit Ailanthus altissima...... forms runners, crooked stem Alnus incana...... crooked stem Betula species and varieties...... crooked stem Celtis australis...... atypical, broken-up crown Cercis siliquastrum...... crooked stem Fraxinus americana varieties...... crooked stem Fraxinus ornus varieties...... no flowers Fraxinus pennsylvanica varieties...... crooked stem Gleditsia triacanthos varieties...... crooked stem Hippophae rhamnoides...... short-lived, forms runners Juglans cinerea...... crooked stem Koelreuteria paniculata...... extremely crooked habit Liquidambar styraciflua...... atypical, broken-up crown Morus nigra...... atypical, broken-up crown Nyssa sylvatica...... crooked stem, atypical, broken-up crown Paulownia tomentosa...... crooked stem, atypical, broken-up crown Platanus acerifolia...... tolerates light shade Populus species and varieties...... short-lived , forms runners Prunus species and varieties...... atypical, broken-up crown, crooked stem Pyrus calleryana varieties...... sensitive to frost Pyrus nivalis...... short-lived, slow-growing Pyrus regelii...... crooked stem Pyrus salicifolia...... short-lived Rhus glabra...... forms runners, short-lived Rhus typhina...... forms runners, short-lived

Groups according to size and growth rates see Tabel no. 1 www.LvE.de | LORENZ VON EHREN 1037 28 Plants that need light Shade-tolerant plants 29

1. Deciduous trees Genus/species/variety Reaction to shade Few plants like shade. Most varieties may tolerate semi-shade or even full shade when young, but the older they get, the more light they need. Plants in the shade regenerate insufficiently. Generous pruning does not cause them to create new shoots, but stops Robinia pseudoacacia varieties...... crooked stem, short-lived shooting altogether in the shade. Full shade does not mean dark shade like in a spruce forest, but only far-reaching protection from sun Salix species and varieties...... crooked habit, short-lived, rays with wandering spots of light during the course of the day. Under the deep-reaching branches of large trees or draped shrubs, no Sophora japonica...... crooked stem, sensitive to frost Tilia euchlora...... atypical, broken-up crown long-term underplanting is possible even with shade-tolerant plants. Tilia henryana...... atypical broken-up crown Tilia tomentosa varieties...... persistent, susceptible to breaking Ulmus ‘Columella’...... crooked habit Ulmus ‘Sapporo Autumn Gold’...... crooked stem Ulmus glabra ‘Pendula’...... less leaves Genus/species/variety Semi-shade Full shade Genus/species/variety Semi-shade Full shade Zelkova serrata...... atypical, broken-up crown 1. Deciduous trees Magnolia stellata varieties ...... (+)...... Acer campestre ...... +...... Mahonia species and varieties ...... +...... +. . . 2. Shrubs Genus/species/variety Reaction to shade Acer platanoides in green- varieties . . . .(+)...... Mespilus germanica ...... +...... Buddleja species and varieties...... no flowers Acer freemanii ...... +...... Osmanthus heterophyllus ...... +...... +. . . Calluna vulgaris varieties...... no flowers, shaggy-unkempt Acer griseum ...... +...... Pachysandra terminalis ...... +...... +. . . Caryopteris clandonensis varieties...... short-lived Acer japonicum varieties...... +...... Philadelphus species and varieties ...... +...... Chionanthus virginicus...... crooked habit Acer pensylvanicum ...... +...... +. . . Photinia villosa ...... +...... Cotoneaster sternianus...... crooked habit Acer rufinerve ...... +...... Pieris species and varieties ...... +...... +. . . Cytisus species and varieties...... short-lived Acer neglectum ’Annae’ ...... +...... (+). . . Prunus laurocerasus varieties ...... +...... +. . . Elaeagnus species and varieties...... crooked habit Carpinus betulus varieties ...... +...... (+). . . Prunus lusitanica ...... +...... +. . . Erica species and varieties...... short-lived, loses its compactness Cornus species and varieties ...... +...... Prunus padus ...... +...... Genista species and varieties...... no flowers Crataegus species and varieties ...... +...... Ptelea trifoliata ...... +...... +. . . Hitocus syriacus varieties...... crooked habit, no flowers Fagus sylvatica all green varieties ...... +...... +. . . Rhamnus species and varieties ...... +...... +. . . Hippophae rhamnoides...... short-lived, forms runners Fraxinus americana ...... +...... Rhododendron species and varieties . . . . . +...... Hypericum kalmianum varieties...... short-lived Fraxinus pennsylvanica ...... +...... Rhodotypos scandens ...... +...... +. . . Lavandula angustifolia varieties...... no flowers, short-lived Ilex aquifolium and varieties ...... +...... +. . . Ribes alpinum varieties ...... +...... +. . . Lespedeza thunbergii...... no flowers Malus sylvestris ...... +...... Ribes aureum ...... +...... Ostrya carpinifolia ...... +...... +. . . Ribes divaricatum ...... +...... Perovskia abrotanoides...... crooked habit, short-lived Prunus padus ...... +...... Rosa arvensis ...... +...... Prunus cistena...... leaves turn green, crooked habit Sorbus aucuparia ...... +...... +. . . Rosa multiflora ...... +...... Prunus mahaleb...... crooked stem, atypical, broken-up crown Sorbus domestica ...... +...... Rubus species and varieties ...... +...... +. . . Rhus typhina varieties...... crooked habit, short-lived Sorbus torminalis ...... +...... +. . . Sambucus species and varieties ...... +...... Ribes sanguineum varieties...... crooked habit, short-lived Stewartia pseudocamellia ...... +...... Skimmia japonica and varieties ...... +...... +. . . Rosa glauca...... crooked habit, short-lived Tilia americana varieties ...... +...... Sorbus species and varieties ...... +...... Salix species and varieties...... crooked habit, short-lived Tilia platyphyllos ...... +...... Sorbaria sorbifolia ...... +...... +. . . Syringa hyacinthiflora varieties...... no flowers Ulmus carpinifolia ...... +...... Spiraea species and varieties ...... +...... Syringa prestoniae varieties...... crooked habit, no flowers Ulmus glabra ...... +...... Staphylea colchica ...... +...... Tamarix species...... crooked habit Stranvaesia davidiana ...... +...... Ulex europaeus...... crooked habit, forms runners 2. Shrubs Stephanandra species and varieties ...... +...... Vaccinium macrocarpon...... short-lived Acer palmatum varieties ...... +...... Stewartia pseudocamellia ...... +...... Aesculus parviflora ...... +...... Vaccinium corymbosum ...... +...... 3. Climbers Genus/species/variety Reaction to shade Aronia species and varieties ...... +...... Vaccinium vitis-idaea varieties ...... +...... +. . . Aucuba japonica and varieties ...... +...... Viburnum species and varieties ...... +...... Campsis tagliabuana...... no flowers Berberis species and varieties ...... +...... Viburnum tinus ...... +...... +. . . Clematis texensis...... no flowers Buxus semervirens varieties ...... +...... +. . . Vinca species and varieties ...... +...... +. . . Jasminum nudiflorum...... no flowers Cornus species and varieties ...... +...... (+). . . Weigela species and varieties ...... +...... Wisteria species and varieties...... few flowers, thinned out Corylus avellana ...... +...... Crataegus species and varieties ...... +...... 3. Climbers 4. Genus/species/variety Reaction to shade Daphne mezereum varieties ...... +...... Actinidia species and varieties ...... +...... Eleaegnus ebbingei ...... +...... Akebia quinata ...... +...... Abies concolor...... turns green Euonymus species and varieties ...... +...... Aristolochia macrophylla ...... +...... +. . . Abies procera ’Glauca’...... turns green Euonymus fortunei varieties ...... +...... +. . . Celastrus orbiculatus ...... +...... +. . . Araucaria araucana...... Fothergilla species ...... +...... +. . . Clematis alpina ...... +...... Cedrus species and varieties...... loses its leaves Gaultheria species and varieties ...... +...... +. . . Clematis tangutica ...... +...... Cupressocyparis leylandii varieties...... thinned out or loses its leaves Hydrangea species and varieties ...... +...... (+). . . Clematis vitalba ...... +...... +. . . Ginkgo biloba...... extremely crooked habit Ilex altaclarensis varieties ...... +...... +. . . Clematis viticella ...... +...... Juniperus species and varieties...... thinned out or loses its leaves Ilex aquifolium varieties ...... +...... +. . . Euonymus fortunei varieties ...... +...... +. . . Larix species and varieties...... crooked stem, atypical, broken-up crown Ilex meserveae varieties ...... +...... Hedera colchica varieties ...... +...... +. . . Picea orientalis varieties...... thinned out or loses its leaves Kalmia species and varieties ...... +...... Hedera helix varieties ...... +...... +. . . Picea glauca varieties...... thinned out or loses its leaves Kerria japonica ...... +...... +. . . Hydrangea petiolaris ...... +...... Picea pungens varieties...... turns green or thinned out or loses its leaves Leucothoe walteri ...... +...... +. . . Lonicera species and varieties ...... +...... Pinus species and varieties...... thinned out or loses its leaves Ligustrum species and varieties ...... +...... (+). . . Parthenocissus species and varieties . . . . . +...... +. . . Pseudolarix amabilis...... crooked stem, atypical, broken-up crown Lonicera species and varieties ...... +...... +. . . Polygonum aubertii ...... +...... Taxodium distichum...... atypical, broken-up crown Explanation of symbols: (+) = of limited usefulness

1038 LORENZ VON EHREN | www.LvE.de www.LvE.de | LORENZ VON EHREN 1039 29 Shade-tolerant plants Wind resistent plants 30

Genus/species/variety Semi-shade Full shade Genus/species/variety Semi-shade Full shade Genus/species/variety Extreme areas All exposures Genus/species/variety Extreme areas All exposures

3. Climbers Picea species and varieties (when young) . . . . . +...... Amelanchier species and varieties ...... +...... +. . . Sorbus species and varieties ...... +. . . Rosa arvensis ...... +...... Sciadopitys verticillata ...... +...... +. . . Aronia species and varieties ...... +. . . Spiraea species and varieties ...... +. . . Rubus caesius ...... +...... +. . . Sequoia sempervirens ...... +...... +. . . Bamboo species and varieties ...... +. . . Syringa vulgaris ...... +...... Rubus fruticosus ...... +...... +. . . Sequoiadendron giganteum ...... +...... Betula species and varieties ...... +. . . Zelkova serrata...... +. . . Rubus henryi ...... +...... +. . . Taxus species and varieties ...... +...... +. . . Caragana arborescens ...... +...... Thuja species and varieties ...... +...... +. . . Corylus colurna ...... +. . . 4. Climbers 4. Conifers Thujopsis dolabrata ...... +...... +. . . Cotoneaster (summer green) ...... +. . . Actinidia arguta ...... +. . . Abies species and varieties (when young) . . .+...... +. . . Tsuga species and varieties ...... +...... +. . . Crataegus species and varieties ...... +. . . Celastrus orbiculatus ...... +. . . Chamaecyparis species and varieties . . . . . +...... Elaeagnus species and varieties ...... +...... Clematis tangutica...... +. . . Explanation of symbols: (+) = of limited usefulness Forsythia species and varieties ...... +. . . Hedera helix...... +. . . Fraxinus americana...... +. . . Hydrangea petiolaris...... +. . . Fraxinus ornus varieties ...... +. . . Parthenocissus quinquefolia ...... +. . . Fraxinus pennsylvanica...... +. . . 30 Wind resistent plants Juglans nigra ...... +...... +. . . 5. Conifers Kolkwitzia amabilis ...... +. . . Abies species and varieties ...... +. . . Ligustrum species and varieties ...... +. . . Araucaria araucana ...... +...... +. . . The wind-resistance of plants is not a constant, but depends on exposure, age and soil substrate, with the exposure playing a decisive Lonicera korolkowii zabelii ...... +. . . Cedrus species and varieties ...... +. . . role. Not every species is capable of growing in extreme, usually westward-oriented areas. Some only survive when other plants sur- Lonicera ledebourii ...... +. . . Chamaecyparis species and varieties ...... +. . . round them or when they are grown on the side of the bed facing away from the wind where shoots, leaves and flowers do not dry out. Lycium barbarum ...... +...... Cupressocyparis leylandii varieties ...... +...... +. . . These reactions are listed in the table along with the varieties that are suitable for all exposed areas – taking into consideration their Philadelphus species and varieties ...... +. . . Ginkgo biloba ...... +. . . other needs such as light needs. For most species, the elasticity of the branches and twigs noticeably decreases with age, which may Photinia villosa ...... +. . . Juniperus species and varieties ...... +. . . mean that species that have great wind-resistance in the first 30 years eventually lose their elasticity and become extremely suscepti- Physocarpos opulifolius ...... +. . . Larix kaempferi ...... +...... +. . . ble to breaking. When this happens, cutting back to further regeneration may be necessary, or the may need to be replaced. On Platanus acerifolia ...... +. . . Metasequoia glyptostroboides ...... +. . . Ptelea trifoliata ...... +. . . Microbiota decussata ...... +. . . heavy soil or when the water level is high, many species have a very shallow root system and are not really anchored in the soil so that Pyracantha species and varieties ...... +. . . Picea sitchensis ...... +...... +. . . they lose their stability as they grow. Here, the remedy is the correct selection of species and occasional pruning. Pyrus calleryana varieties ...... +. . . Pinus species and varieties ...... +. . . Pyrus salcifolia ...... +. . . Sequoia sempervirens ...... +...... +. . . Note: Quercus cerris ...... +...... +. . . Sequoiadendron giganteum ...... +...... +. . . In situations with permanent strong winds or vacuums or at outlets for outgoing warm air, no plant can survive. Quercus species and varieties ...... +. . . Taxus species and varieties ...... +. . . Ribes divaricatum ...... +...... +. . . Thuja species and varieties ...... +. . . Genus/species/variety Extreme areas All exposures Genus/species/variety Extreme areas All exposures Sorbaria sorbifolia ...... +. . . Thujopsis dolabrata...... +. . . Sorbus americana ...... +. . . Tsuga species and varieties...... +. . . 1. Indigenous species Prunus spinosa ...... +...... +. . . Acer campestre ...... +...... +. . . Pyrus communis ...... +. . . Acer platanoides ...... +. . . Quercus petraea ...... +. . . Acer pseudoplatanus ...... +...... +. . . Quercus robur ...... +. . . Alnus glutinosa ...... +. . . Rhamnus species ...... +. . . Plants for damp and flooded soil 31 Alnus incana ...... +...... +. . . Rosa canina ...... +...... Amelanchier ovalis ...... +...... +. . . Rosa glauca ...... +...... Berberis vulgaris ...... +. . . Rosa pimpinellifolia ...... +...... Although many plants can grow in moist to damp soil, most prefer less damp areas. Too much moisture means insufficient oxygen for Betula pubescens ...... +...... Rosa rubiginosa ...... +...... the roots of the plants. In such areas, most plants have extremely shallow roots. Floods are not tolerated equally well in all seasons. Trees Carpinus betulus ...... +...... +. . . Salix species and varieties ...... +. . . with full foliage are extraordinarily sensitive to long floods in summer. Excess moisture and week-long floods are best tolerated from Castanea sativa ...... +. . . Sambucus species and varieties ...... +. . . late winter into spring. Clematis vitalba ...... +. . . Sorbus species and varieties ...... +. . . Colutea arborescens ...... +. . . Ulex europaeus ...... +...... +. . . Genus/species/variety Tolerates dampness Short floods Long floods Cornus mas ...... +. . . Ulmus species and varieties ...... +. . . Cornus sanguinea ...... +...... +. . . Viburnum species and varieties ...... +...... 1. Deciduous trees Crataegus laevigata ...... +. . . Acer campestre ...... -...... +...... - . . . Crataegus monogyna ...... +...... +. . . 2. Indigenous Conifers Acer negundo ...... +...... +...... +. . . Euonymus europaeus ...... +. . . Abies alba ...... +. . . Acer platanoides varieties ...... - ...... +...... -. . . Fagus sylvatica ...... +...... +. . . Juniperus communis varieties ...... +. . . Acer pseudoplatanus varieties ...... +...... +...... -. . . Fraxinus excelsior ...... +. . . Larix decidua ...... +...... +. . . Acer rubrum ...... +...... +...... +. . . Hippophae rhamnoides ...... +...... Pinus cembra ...... +...... +. . . Acer saccharinum varieties ...... +...... +...... +. . . Ilex aquifolium ...... +. . . Pinus mugo ...... +...... +. . . Aesculus flava varieties ...... +...... + ...... - . . . Juglans regia varieties ...... +. . . Pinus sylvestris ...... +. . . Aesculus hippocastanum ...... -...... +...... -. . . Ligustrum vulgare ...... +. . . Taxus baccata ...... +. . . Alnus species and varieties ...... +...... +...... +. . . Malus sylvestris ...... +. . . Aralia elata and varieties ...... +...... +...... Myrica gale ...... +...... 3. Park trees and decorative shrubs Betula nigra ...... +...... +...... -. . . Populus alba ...... +. . . Acer freemanii ...... +. . . Betula pubescens ...... +...... +...... Populus nigra varieties ...... +. . . Acer monspessulanum...... +. . . Carpinus betulus ...... -...... +...... -. . . Populus tremula ...... +...... +. . . Alnus cordata ...... +...... +. . . Catalpa bignonioides ...... +...... +...... -. . . Prunus mahaleb ...... +. . . Alnus spaethii ...... +. . . Cercidiphyllum japonicum ...... -...... +...... -. . .

1040 LORENZ VON EHREN | www.LvE.de www.LvE.de | LORENZ VON EHREN 1041 31 Plants for damp and flooded soil Plants for damp and flooded soil 31

Genus/species/variety Tolerates dampness Short floods Long floods Genus/species/variety Tolerates dampness Short floods Long floods

1. Deciduous trees 2. Shrubs. Corylus colurna ...... +...... +...... -. . . Sorbaria sorbifolia ...... +...... +...... -. . . Fraxinus excelsior varieties...... +...... +...... -. . . Stephanandra incisa ’Crispa’...... +...... +...... -. . . Gleditsia triacanthos varieties...... +...... +...... -. . . Symphoricarpos albus laevigatus...... +...... +...... -. . . Gymnocladus dioicus ...... +...... +...... -. . . Vaccinium corymbosum...... +...... +...... +. . . Juglans regia...... +...... +...... -. . . Viburnum opulus varieties...... +...... +...... +. . . Liquidambar styraciflua ...... +...... +...... +. . . Liriodendron tulipifera...... +...... +...... -. . . Genus/species/variety Tolerates dampness Short floods Long floods Magnolia kobus...... -...... +...... -. . . Malus sylvestris...... -...... +...... -. . . 3. Climbers Nyssa sylvatica...... +...... +...... -. . . Actinidia arguta...... -...... +...... -. . . Platanus acerifolia...... +...... +...... +. . . Akebia quinata...... +...... +...... -. . . Populus species and varieties...... +...... +...... +. . . Aristolochia macrophylla...... +...... +...... +. . . Prunus padus...... +...... +...... +. . . Celastrus orbiculatus...... +...... +...... -. . . Pterocarya fraxinifolia...... +...... +...... +. . . Clematis vitalba...... +...... +...... +. . . Quercus palustris...... +...... +...... -. . . Clematis viticella...... -...... +...... -. . . Quercus robur...... -...... +...... -. . . Euonymus fortunei varieties...... +...... +...... -. . . Salix species and varieties...... +...... +...... +. . . Hedera species and varieties...... +...... +...... -. . . Sorbus decora...... +...... +...... -. . . Lonicera species and varieties ...... -...... +...... -. . . Tilia cordata...... -...... +...... -. . . Parthenocissus quinquefolia...... +...... +...... +. . . Ulmus species and varieties...... -...... +...... -. . . Polygonum aubertii...... +...... +...... -. . . Genus/species/variety Tolerates dampness Short floods Long floods Wisteria sinensis...... +...... +...... +. . .

2. Shrubs. Genus/species/variety Tolerates dampness Short floods Long floods Aesculus parviflora ...... -...... +...... -. . . Amelanchier species and varieties...... +...... +...... -. . . 4. Conifers Aronia species and varieties ...... +...... +...... +. . . Juniperus horizontalis varieties ...... +...... -...... -. . . Betula nana ...... +...... +...... -. . . Metasequoia glyptostroboides ...... +...... +...... -. . . Calycanthus floridus...... +...... +...... -. . . Picea sitchensis...... +...... +...... -. . . Chionanthus virginicus...... +...... +...... -. . . Pinus monticola varieties...... +...... -...... -. . . Clethra alnifolia...... +...... +...... +. . . Pinus sylvestris varieties...... +...... -...... -. . . Cornus alba varieties ...... +...... +...... -. . . Pinus strobus...... +...... -...... -. . . Cornus florida...... +...... +...... -. . . Pinus wallichiana...... +...... -...... -. . . Cornus sanguinea...... -...... +...... -. . . Taxodium distichum...... +...... +...... +. . . Cornus stolonifera varieties...... +...... +...... +. . . Thuja occidentalis varieties...... +...... +...... -. . . Elaeagnus commutata...... -...... +...... -. . . Thuja plicata...... +...... +...... -. . . Erica tetralix...... +...... -...... -. . . Thuja standishii...... +...... -...... -. . . Euonymus europaeus...... +...... +...... -. . . Euonymus yedoensis varieties...... +...... +...... -. . . Fothergilla gardenii...... +...... -...... -. . . Plants that withstand drought 32 Fothergilla major...... -...... +...... -. . . Gaultheria shallon...... +...... +...... +. . . Hippophae rhamnoides...... +...... +...... -. . . Most of the plants listed cannot be considered drought lovers; rather, they tolerate droughts. Many of them primarily like light and only move Holodiscus discolor ariifolius...... +...... +...... -. . . into dry areas because more aggressive plants do not follow them there. Hydrangea species and varieties...... +...... +...... -. . . Ilex verticillata...... +...... +...... +. . . The planting phase is critical as the plants have to be watered regularly to grow normally. After planting, they need to be watered regularly in Kalmia species and varieties...... +...... +...... -. . . the first few years—more often in dry periods. Stress due to drought means, for most plants, that their growth and foliage are reduced, their Ledum palustre...... +...... +...... +. . . autumn colours appear earlier, their frost hardiness is reduced, and the plants are more sensitive to pollution. The plants may also have more Leucothoe walteri...... +...... +...... insects or mites, which would lead to more difficulties in extreme situations. Lonicera caerulea...... +...... +...... -. . . Lonicera ledebourii...... +...... +...... -. . . Note: Magnolia stellata...... +...... +...... -. . . The plants that are more sensitive after planting or when young have been noted. Myrica gale...... +...... +...... -. . . Parrotia persica...... +...... +...... -. . . Genus/species/variety Response to drought Genus/species/variety Response to drought Pernettya mucronata varieties...... +...... +...... -. . . Prunus padus...... +...... +...... +. . . 1. Deciduous trees Acer tataricum...... resistant Rhamnus frangula...... +...... +...... +. . . Acer buergerianum...... resistant Ailanthus altissima...... Azaleen-hybrids...... +...... +...... -. . . Acer campestre varieties...... resistant Alnus cordata ...... sensitive when young Rubus caesius...... +...... +...... +. . . Acer cappadoicum...... resistant Alnus incana ...... sensitive when young Rubus fruticosus...... +...... +...... -. . . Acer ginnala...... Alnus spaethii...... resistant Rosa arvensis...... +...... +...... -. . . Acer monspessulanum...... resistant Amlanchier arborea...... resistant Salix species and varieties...... +...... +...... +. . . Acer negundo ...... only as shrub Betula jacquemontii...... resistant Sambucus nigra...... +...... +...... -. . . Acer rubrum...... resistant Betula nigra ...... sensitive when young

1042 LORENZ VON EHREN | www.LvE.de www.LvE.de | LORENZ VON EHREN 1043 32 Plants that withstand drought Plants for alkaline soil 33

Genus/species/variety Response to drought Genus/species/variety Response to drought Many of the plants named occur on even neutral or slightly acidic soil in the wild without any noticeable problems. Soil humidity, structure and nutrition play important roles in addition to the soil pH. Numerous exotic species do not bind to chalk or alkaline soil in their native habitat, but Castanea sativa ...... grows poorly Genista species and varieties...... rather respond with indifference. In contrast, in central Europe they prefer chalky soil where they can withstand more drought, are less damaged Carpinus betulus...... resistant Hippophae rhamnoides ...... needs residue moisture by frost, and can compete with strong-growing competition better. In conclusion, it is a complex matter that cannot be stated in general terms Celtis australis...... resistant Ilex ‘Nellie R. Stevens’...... resistant for every species. Corylus colurna ...... grows poorly Lespedeza thunbergii ...... more resistant when mature Crataegus species and varieties . . . . . -grid must remain open Ligustrum species and varieties ...... sensitive during planting Fraxinus ornus...... resistant Lycium barbarum...... 1. Deciduous trees Ceanothus delilianus ’Gloire de Versailles’ Salix purpurea varieties Fraxinus pennsylvanica varieties...... resistant Mespilus germanica ...... more resistant when mature Acer campestre varieties Cercis siliquastrum Salix repens argentea Gledtisia triacanthos varieties . . . . not very susceptible to breaking Osmanthus heterophyllus ...... grows poorly Acer cappadocicum varieties Chionanthus virginicus Salix viminalis Koelreuteria paniculata...... Perovskia species and varieties ...... stands on its own better Acer freemanii varieties Colutea arborescens varieties Sambucus canadensis varieties Sambucus nigra Liquidamber styraciflua...... resistant Physocarpus opulifolius ...... sensitive when young Acer monspessulanum Cornus mas Sorbaria sorbifolia Magnolia kobus...... resistant Prunus mahaleb ...... very resistant Acer platanoides varieties Cornus sanguinea Corylus species and varieties Spiraea bumalda varieties Malus tschonoskii ...... sensitive when young Prunus spinosa ...... twigs have more thorns Acer pseudoplatanus varieties Acer neglectum ’Annae’ Cotinus coggygria varieties Spiraea decumbens Morus alba ...... very resistant Prunus lusitanica varieties...... resistant Alnus incana Cotoneaster species and varieties Spiraea japonica varieties Morus nigra ...... sensitive when young Pyracantha hybrids ...... twigs have more thorns Alnus spaethii Crataegus species and varieties Spiraea nipponica Nyssa sylvatica...... resistant Rhamnus catharticus...... like thickets Celtis australis Cytisus beanii Spiraea vanhouttei Ostrya carpinifolia...... resistant Rhus species and varieties ...... more runners Corylus colurna Cytisus decumbens Staphylea colchica Parrotia persica...... resistant Robinia species and varieties ...... very resistant Crataegus species and varieties Cytisus kewensis Syringa species and varieties Paulownia tomentosa ...... very resistant Rosa carolina ...... grows poorly Elaeagnus angustifolia Cytisus nigricans varieties Tamarix species and varieties Populus species and varieties ...... only as shrub, short-lived Rosa gallica ...... forms runners Euodia hupehensis Cytisus purpureus Viburnum bodnantense ’Dawn’ Prunus fruticosa ’Globosa’ ...... sensitive when young Rosa glauca ...... very resistant Fraxinus species and varieties Daphne species and varieties Viburnum burkwoodii Pyrus nivalis...... resistant Rosa pimpinellifolia ...... loses its foilage bearly Gleditsia triacanthos varieties Elaeagnus species and varieties Viburnum carlcephalum Pyrus species and varieties ...... more resistant when mature Rosa rubiginosa ...... grows poorly Gymnocladus dioicus Erica carnea varieties Viburnum farreri Pyrus salicifolia ...... more resistant when mature Rosa rugosa ...... very resistant Juglans nigra Euonymus europaeus Viburnum lantana Quercus cerris ...... crooked stem, only as shrub Rosa rugotida ...... very resistant Juglans regia Euonymus planipes Viburnum opulus Quercus frainetto ...... sensitive when young Salix repens argentea ...... needs residue moisture Koelreuteria paniculata Forsythia species and varieties Viburnum rhytidophyllum Quercus macranthera...... Spiraea decumbens ...... Laburnum species and varieties Genista radiata Viburnum tinus Vinca species and varieties Quercus palustris...... resistant Syringa vulgaris...... Malus species and varieties Hitocus syriacus varieties Quercus petraea ...... crooked stem, only as shrub Tamarix species and varieties ...... very resistant Morus species and varieties Hippophae rhamnoides 3. Climbers Quercus turneri ’Pseudoturneri’ ...... bushy Ulex europaeus...... Ostrya carpinifolia Hypericum kalmianum ’Gemo’ Actinidia arguta Rhus species and varieties ...... more runners Viburnum lantana...... Paulownia tomentosa Laburnum species and varieties Aristolochia macrophylla Robinia species and varieties...... Phellodendron amurense Lavandula angustifolia varieties Campsis radicans varieties Sophora japonica varieties ...... more resistant when mature 3. Climbers Platanus acerifolia varieties Ligustrum species and varieties Clematis species and varieties Sorbus aria varieties ...... sensitive when young Campsis radicans ...... grows poorly Platanus orientalis Lonicera japonica repens Euonyms fortunei varieties Sorbus domestica ...... grows poorly Campsis tagliabuana ...... resistant Populus alba ’Nivea’ Lonicera korolkowii zabelii Hedera species and varieties Sorbus thuringiaca ’Fastigiata’ ...... sensitive when young Celastrus orbiculatus ...... slow-growing Populus canescens Lonicera xylosteum varieties Jasminum nudiflorum Sorbus torminalis ...... grows poorly Clematis maximowicziana ...... sensitive when young Populus nigra varieties Lycium barbarum Lonicera species and varieties Tilia platyphyllos varieties...... resistant Clematis vitalba ...... slow-growing Prunus species and varieties Malus species and varieties Parthenocissus quinquefolia varieties Tilia tomentosa ...... sensitive when young Euonymus fortunei varieties ...... hardly climbs Pyrus species and varieties Mespilus germanica Polygonum aubertii Ulmus holandica varieties...... resistant Hedera species and varieties ...... sensitive to frost Quercus species and varieties Osmanthus heterophyllus Rosa - Climbers Zelkova serrata varieties...... Jasminum nudiflorum...... Rhamnus catharticus Perovskia abrotanoides Parthenocissus quinquefolia . . . . thinned out, sensitive when young Rhus typhina Philadelphus species and varieties 4. Conifers 2. Shrubs Robinia species and varieties Prunus species and varieties Abies concolor Acanthopanax sieboldianus ...... grows poorly 4. Conifers Salix alba varieties Ptelea trifoliata Cedrus atlantica varieties Amelanchier ovalis ...... leaves fall early Abies concolor ...... sensitive when young Salix daphnoides varieties Pyracantha hybrids Cedrus libani Berberis ottawensis ’Superba’...... Cedrus species and varieties ...... sensitive when young Sophora japonica varieties Rhamnus catharticus Chamaecyparis nootkatensis varieties Berberis thunbergii varieties ...... thinned out Cupressocyparis leylandii ...... grows poorly, thinned out Sorbus aria varieties Rhus typhina varieties Ginkgo biloba Berberis vulgaris ...... very resistant Ginkgo biloba ...... grows poorly Sorbus domestica Ribes species and varieties Juniperus chinensis varieties Buddleja species and varieties ...... flowers wither faster Juniperus species and varieties ...... very resistant Sorbus intermedia varieties Rhodotypos scandens Juniperus communis varieties Caragana arborescnes...... Picea orientalis ...... sensitive when young Sorbus thuringiaca ’Fastigiata’ Rhus species and varieties Juniperus media varieties Robinia hispida varieties Cercis siliquastrum ...... more resistant when mature Picea pungens varieties...... Sorbus torminalis Juniperus sabina varieties Tilia species and varieties Rosa arvensis Colutea arborescens ...... sensitive when young Pinus contorta ...... sqat Juniperus squamata varieties Ulmus species and varieties Rosa canina varieties Cornus mas ...... sensitive when young Pinus densiflora ’Umbraculifera’...... Juniperus virginiana varieties Zelkova serrata varieties Rosa gallica Cornus sanguinea...... Pinus jeffreyi ...... grows poorly Larix decidua Rosa glauca Microbiota decussata Cotinus coggygria varieties ...... more resistant when mature Pinus leucormis ...... very resistant 2. Shrubs Rosa moyesii Picea orientalis varieties Cotoneaster dielsianus ...... sensitive when young Pinus mugo varieties ...... sensitive when young Acanthopanax sieboldianus Rosa multibracteata Picea pungens varieties Cotoneaster divaricatus ...... sensitive when young Pinus nigra varieties...... sensitive during planting Amelanchier ovalis Rosa pimpinellifolia Pinus aristata Cotoneaster franchetii ...... sensitive when young Pinus peuce ...... sensitive during planting Berberis species and varieties Rosa rubiginosa Pinus leucormis Cotoneaster sternianus ...... grows poorly Pinus ponderosa ...... sensitive during planting Buddleja species and varieties Rubus calycinoides Pinus mugo varieties Crataegus species and varieties...... Pinus sylvestris varieties...... Buxus sempervirens varieties Rubus idaeus Pinus nigra austriaca varieties Cytisus species and varieties...... Pseudotsuga menziesii caesia ...... grows poorly Caragana arborescens Salix elaeagnos Taxus species and varieties Elaeagnus species and varieties ...... very resistant Caryopteris species and varieties Salix hastata ’Wehrhahnii’ Thuja occidentalis varieties

1044 LORENZ VON EHREN | www.LvE.de www.LvE.de | LORENZ VON EHREN 1045 34 Plants for acidic soil Plants for light, sandy soil 35

The degree of acidity of the soil depends, among other things, on the original rock type. Acidic soil can be of purely mineral (acidic sand or Few plants grow willingly on sandy soil. Those that do are forced into the sand by stronger competitors. If these competitors are absent, most loam) or organic origin. The degree of acidity is stated as its pH value, with the range for acid-loving plants between pH 4 and pH 6.5. Between of the plants named are quite able to thrive on normal soil. Almost all of the plants listed grow better if the sandy soil is somewhat fresh or even pH 6.5 and approx. pH 7.2, one speaks of neutral soil; above that, of alkaline. The pH value on its own does not tell us everything; a slightly acidic moist, contains loamy or humic components, and is not too lacking in nutrients. Just because the plants concerned settle on sandy soil does not soil of pH 6, where air humidity is high and humus is present, is better for plants than a soil of pH 6 would be in a situation where the plants are mean they prefer a lack of nutrients or drought. It should also be kept in mind that sandy soil does not necessarily mean the soil is acidic, for the exposed to heat and drought on non-nutritious sand or gravel. pH values may be far into the alkaline range.

Note: Plants that have to make do with sandy soil differ from their relatives on better substrates in, among other things, their multiple stems, crooked Many of the species named thrive well in neutral soil, some of them even in slightly alkaline soil (see the individual descriptions). growth, more plentiful runners, and shorter-lived leaves. Species susceptible to frost or breaking are at an advantage, however, on sandy soil; they are more prone to damage on loam or clay. 1. Deciduous trees Cornus canadensis Spiraea betulifolia varieties Acer freemanii varieties Cornus controversa Spiraea prunifolia Acer griseum Cornus florida varieties Spiraea thunbergii 1. Deciduous trees 2. Shrubs Prunus serotina Acer japonicum varieties Cornus kousa varieties Stephanandra incisa ’Crispa’ Acer campestre Acer freemanii varieties Rhamnus catharticus Acer negundo varieties Cornus nuttallii Syringa patula varieties Acer ginnala Acer ginnala Rhamnus frangula Acer pensylvanicum Corylopsis species and varieties Ulex europaeus Acer negundo varieties Acer monspessulanum Rhus species and varieties Acer rubrum Cytisus hybrids Vaccinium species and varieties Acer platanoides varieties Acer tataricum Ribes aureum Acer rufinerve Cytisus scoparius Acer rubrum varieties Amelanchier species Ribes divaricatum Acer saccharum Daboecia species and varieties 3. Climbers Acer saccharinum varieties Arctostaphylos uva-ursi Rosa glauca Acer saccharinum varieties Empetrum nigrum Hydrangea petiolaris Acer neglectum ’Annae’ Berberis ottawensis ’Superba’ Rosa multiflora Ailanthus altissima Enkianthus campanulatus Lonicera periclymenum Ailanthus altissima Berberis thunbergii varieties Rosa nitida Alnus glutinosa Erica cinerea varieties Rosa multiflora Alnus cordata Buddleja alternifolia Rosa pimpinellifolia Amelanchier species and varieties Erica tetralix varieties Rubus fruticosus Alnus incana Calluna vulgaris varieties Rosa rugotida Betula species and varieties Erica vagans varieties Wisteria species and varieties Amelanchier species Caragana arborescens Rosa rugosa Castanea sativa Escallonia species and varieties Betula species and varieties Ceanothus delilianus ’Gloire de Versailles’ Rubus calycinoides Cornus alternifolia Fothergilla species and varieties 4. Conifers Castanea sativa Chaenomeles speciosa Salix species and varieties Cornus controversa Gaultheria species Abies balsamea ’Nana’ Cornus kousa Colutea arborescens Symphoricarpos species and varieties Cornus florida varieties Genista species and varieties Abies homolepis Elaeagnus angustifolia Cornus kousa Tamarix species and varieties Cornus kousa and C. kousa chinensis Halesia carolina Fraxinus ornus Cornus mas Vaccinium vitis-idaea varieties Hamamelis species and varieties Abies procera ’Glauca’ Fraxinus americana varieties Gleditsia triacanthos varieties Cornus sanguinea Viburnum lantana Fraxinus pennsylvanica varieties Hebe ochracea Abies veitchii Hippophae rhamnoides Cornus stolonifera ’Flaviramea’ Ilex aquifolium Hydrangea species and varieties Araucaria araucana Koelreuteria paniculata Cotinus coggygria varieties 3. Climbers Liquidambar styraciflua Ilex species and varieties Cedrus deodara varieties Populus species and varieties Cotoneaster dielsianus Actinidia arguta Liriodendron tulipifera varieties Kalmia angustifolia ’Rubra’ Chamaecyparis lawsoniana varieties Prunus mahaleb Cytisus species and varieties Akebia quinata Magnolia grandiflora ‘Blanchard’ Ledum palustre Chamaecyparis pisifera varieties Prunus serotina Elaeagnus species and varieties Aristolochia macrophylla Magnolia species and varieties Lespedeza thunbergii Chamaecyparis obtusa varieties Pyrus salicifolia Erica cinerea Celastrus orbiculatus Nyssa sylvatica Leucothoe walteri Cryptomeria japonica varieties Quercus cerris Genista species and varieties Jasminum nudiflorum Parrotia persica Lonicera caerulea Cupressocyparis leylandii varieties Quercus coccinea Hippophae rhamnoides Parthenocissus quinquefolia varieties Populus tremula Lonicera ledebourii Juniperus species and varieties Quercus coccinea Magnolia species and varieties Picea breweriana Quercus petraea Hypericum calycinum Polygonum aubertii Quercus palustris Myrica gale Picea glauca varieties Quercus rubra Hypericum kalmianum ’Gemo’ Wisteria sinensis Quercus rubra Parrotia persica Picea sitchensis Rhamnus catharticus Lespedeza thunbergii Salix fragilis Pernettya mucronata varieties Pinus banksiana Rhus typhina Ligustrum species and varieties 4. Conifers Sorbus aucuparia varieties Photinia villosa Pinus contorta varieties Robinia pseudoacacia varieties Lycium barbarum Abies concolor Sorbus americana Pieris species and varieties Pinus jeffreyi Salix species and varieties Perovskia abrotanoides Juniperus species and varieties Sorbus arnoldiana varieties Potentilla fruticosa varieties Pinus monticola varieties Sophora japonica Physocarpus opulifolius Larix kaempferi Sorbus decora Rhamnus frangula Pinus mugo Sorbus aucuparia Potentilla fruticosa varieties Picea sitchensis Sorbus koehneana Rhododendron species and varieties Pinus ponderosa Sorbus intermedia Prunus mahaleb Pinus species and varieties Stewartia pseudocamellia Rosa blanda Pinus pumila varieties Styrax japonicus Rosa carolina Pinus schwerinii Styrax obassia Rosa multiflora Pinus strobus varieties Rosa rugotida Pinus wallichiana varieties 2. Shrubs Rosa rugosa varieties Pseudolarix amabilis Acer japonicum varieties Rubus calycinoides Sciadopitys verticillata Acer palmatum varieties Rubus fruticosus Sequoia sempervirens Arctostaphylos uva-ursi Salix aurita Sequoiadendron giganteum varieties Aronia species and varieties Salix balsamifera mas Taxodium distichum Amelanchier species and varieties Salix cinerea Thuja occidentalis varieties Berberis thunbergii species and varieties Salix helvetica Thuja plicata varieties Betula nana Salix lanata Thuja standishii Callicarpa bodinieri ’Profusion’ Salix repens argentea Thujopsis dolabrata Calluna vulgaris varieties Salix sachalinensis ’Sekka’ Tsuga canadensis varieties Chaenomeles species and varieties Salix triandra Tsuga diversifolia Clethra alnifolia Sambucus racemosa Cornus alternifolia Skimmia japonica varieties

1046 LORENZ VON EHREN | www.LvE.de www.LvE.de | LORENZ VON EHREN 1047 36 Plants for heavy, loamy soil or clay Plants resistent to industrial pollution 37

Heavy loam, loess, or even clay are not optimal soil substrates for most plants. Plant habits are much smaller than on normal loam. Some trees Resistant to Negative Resistant to Negative and shrubs, such as Chaenomeles, react to this poorly aerated soil with chlorosis (yellowing of the leaves), with sensitivity to fungi (such as Genus/species/variety industrial pollution Experience Genus/species/variety industrial pollution Experience Juniperus), or with early leaf loss (such as with many Sorbus varieties). Other examples of sensitivity would be the the extreme frost damage to Cotoneaster or the weakened habit of Picea abies. Soil improvements and loosening are therefore desirable to prevent or reduce such damage. 1. Deciduous Erica vagans ...... +...... Acanthopanax sieboldianus ...... ++...... Euonymus europaeus ...... ++...... Note: Acer campeste ...... ++...... *. . . . Euonymus fortunei varieties ...... +...... The list does not include any plants occasionally considered tolerant of clay but that displayed severe defects in the course of decades of Acer freemanii...... +...... Fagus sylvatica ...... +...... observation in the test garden at Weihenstephan near Munich (heavy loess). Acer ginnala ...... ++...... Forsythia intermedia ...... +...... *. . . . Acer negundo ...... ++...... *. . . . Fraxinus excelsior ...... ++...... Acer platanoides varieties ...... ++...... *. . . . Fraxinus angustifolia ‘Raywood’ ...... +...... *. . . . 1. Deciduous trees Colutea arborescens Rubus idaeus Acer rubrum varieties ...... ++...... *. . . . Gaultheria procumbens ...... +...... Acer negundo varieties Cornus alba varieties Salix species and varieties Acer saccharinum varieties ...... ++...... Gaultheria shallon ...... +...... Acer platanoides varieties Cornus mas Sambucus species and varieties Aesculus hippocastanum varieties ...... +...... Genista tinctoria ...... +...... Acer saccharinum varieties Cornus sanguinea Sorbaria sorbifolia Aesculus parviflora ...... ++...... Gleditsia triacanthos ...... ++...... Aesculus species and varieties Cornus stolonifera ’Flaviramea’ Spiraea species and varieties Ailanthus altissima ...... ++...... Gymnocladus dioicus ...... +...... Alnus species and varieties Corylus avellana Symphoricarpos species and varieties Alnus glutinosa ...... ++...... *. . . . Hamamelis japonica ...... +...... Aralia elata varieties Corylus maxima ’Purpurea’ Syringa species and varieties Alnus incana ...... ++...... *. . . . Hippophae rhamnoides ...... +...... Betula nigra Cotoneaster species and varieties Viburnum lantana Amelanchier species ...... +...... Hypericum calycinum ...... +...... Carpinus betulus varieties Crataegus species and varieties Viburnum opulus varieties Aucuba japonica ...... ++...... Ilex aquifolium ...... ++...... *. . . . Crataegus species and varieties Deutzia species and varieties Viburnum plicatum varieties Berberis buxifolia ‘Nana’ ...... +...... Ilex crenata ...... +...... Fagus sylvatica varieties Euonymus europaeus Weigela species and varieties Berberis gagnepainii lanceifolia ...... +...... Juglans nigra ...... +...... Fraxinus americana microcarpa Euonymus fortunei varieties Berberis julianae ...... +...... Kalmia angustifolia ...... +...... Fraxinus americana varieties Euonymus planipes 3. Climbers Berberis stenophylla ...... +...... Laburnum anagyroides ...... +...... Fraxinus excelsior varieties Forsythia intermedia varieties Aristolochia macrophylla Berberis thunbergii ...... ++...... *. . . . Leucothoe walteri ...... +...... Berberis verruculosa ...... ++...... Ligustrum vulgare varieties ...... ++...... Fraxinus pennsylvanica Hamamelis species and varieties Celastrus orbiculatus Betula papyrifera ...... +...... Liriodendron tulipifera ...... ++...... Gymnocladus dioicus Hypericum calycinum Clematis tangutica * Betula pendula ...... ++...... Lonicera nitida varieties ...... +...... Ilex aquifolium varieties Ilex aquifolium varieties Clematis vitalba * * Betula pubescens ...... +...... Lonicera pileata ...... +...... Juglans nigra Kerria japonica varieties Euonymus fortunei varieties Laburnum species and varieties Laburnum species and varieties Buddleja davidii varieties ...... +...... Lonicera tatarica ...... ++...... Hedera helix * Liquidambar styraciflua Ligustrum vulgare varieties Buxus sempervirens ...... ++...... Lonicera xylosteum ...... +...... Parthenocissus quinquefolia varieties Lonicera maackii Lonicera ledebourii Calycanthus floridus ...... ++...... Lycium barbarum ...... ++...... Parthenocissus tricuspidata ’Veitchii’ Magnolia kobus Lonicera maackii Calluna vulgaris ...... +...... Mahonia aquifolium ...... +...... Polygonum aubertii * Populus species and varieties Lonicera xylosteum Caragana arborescens ...... +...... *. . . . Mahonia bealei ...... +...... *. . . . Rosa arvensis Prunus avium Mahonia aquifolium varieties Castanea sativa ...... ++...... Malus sylvestris ...... +...... Rubus caesius Prunus padus varieties Philadelphus species and varieties Catalpa bignonioides ...... ++...... Malus hybrids ...... +...... Rubus fruticosus Prunus serrulata varieties Physocarpus opulifolius Cercidiphyllum japonicum ...... +...... Morus species and varieties ...... +...... Pterocarya fraxinifolia Potentilla species and varieties Chaenomeles japonica ...... +...... *. . . . Nyssa sylvatica ...... ++...... Quercus palustris Prunus spinosa 4. Conifers Chaenomeles speciosa ...... +...... Osmanthus heterophyllus ...... +...... Quercus robur Pseudosasa japonica Abies nordmanniana Chionanthus virginicus ...... ++...... Pachysandra terminalis ...... +...... Chamaecyparis species and varieties Rhamnus catharticus Rhamnus species Colutea arborescens ...... +...... *. . . . Paulownia tomentosa ...... +...... Salix species and varieties Ribes species and varieties Juniperus media varieties Cornus alba varieties ...... +...... *. . . . Phellodendron amurense ...... +...... Tilia species and varieties Rosa arvensis Larix species and varieties Cornus florida varieties ...... ++...... Philadelphus coronarius ...... +...... Zelkova serrata varieties Rosa canina Metasquoia glyptostroboides Cornus mas ...... +...... *. . . . Philadelphus ‘Erectus’ ...... +...... Rosa multibracteata Picea orientalis varieties Cornus sanguinea ...... ++...... *. . . . Physocarpus opulifolius ...... +...... *. . . . 2. Shrubs Rosa rubiginosa Picea pungens varieties Cornus stolonifera ‘Flaviramea’ ...... +...... Pieris floribunda ...... ++...... Aralia elata Rubus caesius Taxus species and varieties Cotoneaster acutifolius ...... +...... Pieris japonica ...... +...... Bamboo species and varieties Rubus fruticosus Thuja species and varieties Cotoneaster adpressus ...... +...... Platanus acerifolia ...... ++...... Cotoneaster dammeri...... +...... Populus balsamifera ...... +...... *. . . . Cotoneaster divaricatus ...... +...... Populus berolinensis ...... +...... Cotoneaster horizontalis ...... +...... Populus canadensis varieties ...... ++...... *. . . . Cotoneaster microphyllus ‘Cochleatus’ . . .+...... Populus tremula ...... ++...... 37 Plants resistent to industrial pollution Cotoneaster salicifolius floccosus . . . . . +...... Prunus avium ...... +...... Cotoneaster watereri ...... +...... Prunus cerasifera ‘Nigra’ ...... +...... Corylus avellana ...... +...... Prunus laurocerasus varieties ...... +...... Resistance to industrial pollution cannot be stated in set figures. A majority of those on the list are included based on mere observation; few Crataegus lavallei ‘Carrierei’ ...... ++...... *. . . . Prunus mahaleb ...... +...... were systematically measured or even tested with exposure to gases. It is thus not surprising that much information is contradictory. These Crataegus monogyna ...... ++...... Prunus padus ...... ++...... contradictions result from observations dating back to the end of the 19th century, the beginning of the 50s, and the 70s. Tests were carried out Crataegus prunifolia ...... +...... *. . . . Prunus serotina ...... ++...... *. . . . in various regions, some even overseas, so that the findings can hardly be compared. In the meantime, air pollution, measurement accuracy, and Daphne mezereum ...... +...... Prunus serrulata varieties ...... +...... the assessment of toxins have changed so much that a general review is needed. Furthermore, sensitivity to industrial pollution depends among Deutzia scabra varieties ...... +...... Prunus spinosa ...... ++...... other things on nutritional conditions and exposure to heat and drought, which means that the same species may respond differently under Elaeagnus angustifolia ...... ++...... Pyracantha coccinea ...... ++...... *. . . . varying circumstances. Of course, seasonal conditions also play a role. Elaeagnus commutata ...... ++...... *. . . . Pyrus calleryana varieties ...... +...... Elaeagnus pungens varieties ...... +...... Quercus petraea ...... ++...... The table cannot, therefore, give any conclusive answers. Erica carnea ...... +...... Quercus palustris ...... ++......

Explanation of symbols: ++ = sufficiently resistant to industrial pollution / + = resistant to industrial pollution / * = contradictory or mostly negative experience

1048 LORENZ VON EHREN | www.LvE.de www.LvE.de | LORENZ VON EHREN 1049 37 Plants resistent to industrial pollution Salt-tolerant plants 38

Resistant to Negative Resistant to Negative 1. Deciduous trees Genus/species/variety Salt tolerant Contradictory experience Tolerance of salty air Genus/species/variety industrial pollution Experience Genus/species/variety industrial pollution Experience Carpinus betulus...... +...... *...... Quercus rubra ...... ++...... Viburnum lantana ...... ++...... *. . . . Elaeagnus species and varieties...... ++...... +...... Quercus turneri ‘Pseudoturneri’ ...... +...... Viburnum opulus ...... ++...... Fraxinus excelsior...... ++...... *...... Ribes alpinum ...... ++...... *. . . . Viburnum rhytidophyllum ...... +...... Gleditsia triacanthos varieties...... ++...... Ribes aureum ...... +...... Vinca species and varieties ...... +...... Gymnocladus dioicus...... ++...... Rhododendron catawbiense varieties . . ++...... Weigela ‘Eva Rathke’ ...... ++...... Hippophae rhamnoides...... ++...... *...... +...... Rhododendron - Japanese Azaleas . . . . +...... Weigela florida ...... +...... Juglans regia...... ++...... *...... Rhodotypos scandens ...... +...... Malus hybrids...... +...... *...... Rhus species and varieties ...... ++...... *. . . . 2. Climbers Malus sylvestris...... +...... *...... Robinia pseudoacacia ...... ++...... *. . . . Celastrus orbiculatus ...... ++...... Morus species and varieties...... +...... Rosa canina ...... ++...... *. . . . Hedera colchica ...... +...... Nyssa sylvatica...... ++...... Rosa pimpinellifolia ...... +...... Hedera helix ...... ++...... Platanus acerifolia...... ++...... *...... Populus alba...... ++...... +...... Rosa rubiginosa ...... +...... Parthenocissus quinquefolia ...... +...... *. . . . Populus berolinensis...... +...... Rosa rugosa ...... +...... *. . . . Rubus fruticosus ...... +...... Populus canadensis varieties...... ++...... Rubus fruticosus ...... +...... Wisteria sinensis ...... +...... *. . . . Salix acutifolia ‘Pendulifolia’ ...... +...... Populus canescens...... ++...... Salix alba ...... ++...... 3. Conifers Populus nigra ’Italica’...... +...... *...... * Populus simonii...... +...... Sambucus nigra ...... ++...... Abies balsamea ‘Nana’ ...... +...... * Populus tremula...... ++...... Sambucus racemosa ...... +...... Abies concolor ...... ++...... * * Prunus avium...... ++...... Skimmia japonica ...... +...... Cedrus atlantica ‘Glauca’ ...... +...... * * Prunus serotina...... ++...... +...... Sophora japonica varieties ...... ++...... Chamaecyparis species and varieties . . . +...... * Pyrus calleryana ’Chanticleer’...... +...... Sorbus aria ...... ++...... Ginkgo biloba ...... ++...... Quercus robur...... ++...... Sorbus aucuparia ...... +...... *. . . . Juniperus species and varieties ...... ++...... *. . . . Quercus rubra...... ++...... Spiraea bumalda ...... ++...... Larix kaempferi ...... +...... * Rhus species and varieties...... ++...... *...... +...... Spiraea vanhouttei ...... +...... Metasequoia glyptostroboides ...... ++...... * Robinia species and varieties...... ++...... *...... +...... Stranvaesia davidiana ...... +...... Picea omorika ...... +...... *. . . . Salix alba...... +...... Symphoricarpos albus laevigatus . . . . . ++...... Picea pungens glauca ...... ++...... *. . . . Salix alba ’Tristis’...... ++...... Symphoricarpos chenaultii ...... +...... Pinus species and varieties ...... +...... *. . . . Salix caprea...... +...... Symphoricarpos orbiculatus ...... +...... Pseudotsuga menziesii in Formen . . . . .+...... *. . . . Salix matsudana ’Tortuosa’...... ++...... Syringa vulgaris ...... ++...... *. . . . Taxodium distichum ...... ++...... Sophora japonica...... ++...... Tamarix ramosissima ...... ++...... Taxus baccata ...... ++...... Sorbus aria varieties...... +...... Tilia americana varieties ...... +...... Thuja occidentalis ...... ++...... Sorbus aucuparia...... +...... Tilia cordata ...... ++...... *. . . . Thuja plicata ...... ++...... Ulmus hybrids...... +...... *...... Tilia tomentosa ...... +...... *. . . . Tsuga diversifolia ...... ++...... Explanation of symbols: ++ = sufficiently resistant to industrial pollution / + = resistant to industrial pollution / 2. Shrubs Genus/species/variety Salt tolerant Contradictory experience Tolerance of salty air = contradictory or mostly negative experience * Acer ginnala...... +...... Aesculus parviflora...... ++...... *...... 38 Salt-tolerant plants Amelanchier lamarckii...... +...... Arctostaphylos uva-ursi...... +...... +...... Experience with plants’ salt damage and tolerance varies greatly. That is not surprising as resistance and sensitivity depend on temperatures, Aronia species and varieties...... ++...... precipitation, soil type, and the amount of salt. In cool, rainy areas, the damage is not nearly as severe as in hot, dry areas or in summer. Berberis thunbergii ’Atropurpurea’...... +...... The completely contradictory information that occurs is due to these factors. Calluna vulgaris...... +...... Caragana arborescens...... ++...... Such contradictions either are not found or are rare in indices of resistance to salty air (sea-side areas). Ceanothus delilianus varieties...... ++...... Clethra alnifolia...... +...... * ...... +...... Cornus mas...... +...... Cornus sanguinea...... +...... *...... 1. Deciduous trees Genus/species/variety Salt tolerant Contradictory experience Tolerance of salty air Cornus stolonifera ’Flaviramea’...... *...... +...... Cotoneaster franchetii...... +...... Acer campestre...... ++...... *...... Cotoneaster horizontalis...... +...... Acer negundo...... +...... *...... Crataegus monogyna...... +...... Acer platanoides...... ++...... *...... +...... Elaeagnus angustifolia...... ++...... +...... Acer pseudoplatanus...... ++...... *...... +...... Gaultheria procumbens...... +...... Acer rubrum...... +...... *...... Hippophae rhamnoides...... ++...... *...... +...... Acer saccharinum...... ++...... *...... Hydrangea arborescens varieties...... +...... Aesculus hippocastanum...... +...... *...... Hydrangea hybrids...... +...... Aesculus carnea varieties...... +...... Hydrangea quercifolia...... +...... Ailanthus altissima...... ++...... +...... Hypericum kalmianum varieties...... ++...... Alnus glutinosa...... +...... *...... Kalmia angustifolia...... +...... Alnus incana...... +...... Ligustrum ovalifolium...... +...... Betula pendula...... +...... *...... Ligustrum vulgare...... +...... *...... Explanation of symbols: ++ = tolerance of (resistant to) salt / + = moderately tolerance of (resistant to) salt Explanation of symbols: ++ = tolerance of (resistant to) salt / + = moderately tolerance of (resistant to) salt * = contradictory or mostly negative experience * = contradictory or mostly negative experience

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2. Shrubs Genus/species/variety Salt tolerant Contradictory experience Tolerance of salty air

Lonicera nitida varieties...... +...... Lonicera tatarica...... +...... Lonicera xylosteum...... ++...... *...... Lycium barbarum...... ++...... *...... +...... Mahonia aquifolium...... +...... +...... Malus hybrids...... +...... *...... Philadelphus varieties...... +...... Physocarpus opulifolius...... +...... Potentilla fruticosa varieties...... ++...... *...... Prunus padus...... +...... *...... Prunus serotina...... ++...... *...... Prunus spinosa...... ++...... *...... Ptelea trifoliata...... ++...... Pyracantha hybrids...... +...... +...... Rhamnus catharticus...... ++...... *...... +...... Rhamnus frangula...... +...... *...... +...... Ribes alpinum...... ++...... Ribes aureum...... +...... Rosa canina...... +...... *...... Rosa multiflora...... +...... Rosa nitida...... +...... Rosa pimpinellifolia...... +...... Rosa rubiginosa...... +...... Rosa rugotida...... ++...... Rosa rugosa...... ++...... *...... Salix repens varieties...... +...... Sambucus nigra...... ++...... +...... Spiraea arguta...... +...... Spiraea bumalda ’Anthony Waterer’...... +...... Spiraea vanhouttei...... +...... Symphoricarpos species and varieties...... ++...... *...... Syringa vulgaris...... +...... Tamarix parviflora...... ++...... +...... Tamarix ramosissima...... ++...... +...... Vaccinium corymbosum...... +...... Vaccinium vitis-idaea varieties...... +...... Viburnum burkwoodii...... +...... Viburnum lantana...... ++...... *...... Viburnum opulus...... +...... *......

3. Climbers Genus/species/variety Salt tolerant Contradictory experience Tolerance of salty air

Campsis radicans varieties...... ++...... Celastrus orbiculatus...... ++...... Parthenocissus quinquefolia...... +...... Polygonum aubertii...... +...... Wisteria sinensis...... +......

4. Conifers Genus/species/variety Salt tolerant Contradictory experience Tolerance of salty air

Juniperus communis...... +...... +...... Juniperus horizontalis varieties...... +...... Juniperus media ’Pfitzeriana’...... +...... Juniperus sabina ’Tamariscifolia’...... +...... Juniperus virginiana...... ++...... *...... +...... Picea pungens glauca...... ++...... *...... +...... Pinus banksiana...... ++...... Pinus mugo...... ++...... *...... +...... Pinus nigra austriaca...... ++...... *...... +...... Pinus ponderosa...... +...... Pinus sylvestris...... +...... *...... +......

Explanation of symbols: ++ = tolerance of (resistant to) salt / + = moderately tolerance of (resistant to) salt * = contradictory or mostly negative experience

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