Permaculture Plants: Alder

Alders can be large trees or medium-sized shrubs.

http://upload.wikimedia.org/wikipedia/commons/1/1a/Alnus_glutinosa_011.jpg

Common Name: Alder

Scientific Name: Alnus species

Family: Betulaceae (the Birch family)

Common Species:

• Italian Alder (Alnus cordata) – Medium, standard tree
• Black/Common Alder (Alnus glutinosa) – Large, standard tree
• Gray/Thinleaf Alder (Alnus incana) – Large, standard tree
• Seaside Alder (Alnus maritime) – Medium, standard tree
• Red Alder (Alnus rubra) – Large, standard tree
• Speckled Alder (Alnus incana subspecies rugosa) – Very large, multi-stemmed shrub
• Smooth/Hazel Alder (Alnus serrulata) – Large, multi-stemmed shrub

Red Alder buds and leaves.

http://www.just-green.com/ProductImages/fullsize/red_alder.jpg

 

Description:

Alders are very fast growing large shrubs to tall trees found throughout the Northern Hemisphere. One of the few trees that put nitrogen back into the soil, these plants have many other uses including windbreaks, hedges, firewood, timber, pollen and nectar source for beneficial insects, erosion control, habitat restoration, and traditional medicine to name but a few. Definitely a plant worth considering if you have the room.

Alnus glutinosa

http://luirig.altervista.org/cpm/albums/sturm1/alnus-glutinosa-0030.jpg

History:

There are 30 species of flowering trees and shrubs that are native to the northern Temperate Climates of the Earth. They are mainly pioneer species that have been used as windbreaks and hedges as well as for wood. Most native cultures have medicinal uses for different parts of the plant as well. However, there has been very little development of these plants.

Trivia:

Alder’s flowers are born in cylindrical clusters called catkins.

Alder flowers (catkins) are not large, but attract a lot of beneficial insects.

https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhUvmhrU6Qx3Q7QwpE4HSJ8hn6rIvpMPDu-pD3Q7o9Fq2iGnmoPxl9FAaXl83Qu3TCxGspGclAFLyKInZvLMqTbM5CoYKbK2BI8ZphTk3I0NunNw1XdfBIBPXaJi5VvCXL0SYCMdg5DZzqc/s1600/catkin.JPG

USING THIS PLANT

Primary Uses:

• Ornamental tree or large shrub
• Nitrogen Fixer – puts nitrogen back into the soil which may be used as a fertilizer to other plants (actinorhizal)
• Windbreak or hedge (some species are great in maritime climates: Black, Italian, Gray, Seaside Alders)
• Wood – Firewood, Timber, Furniture, Paper, Mushroom Production

Secondary Uses:

• General insect (especially bees) nectar and pollen plant
• Coppice plant (harvest every 12-25 yrs for kindling, firewood, tool handles, crafts, poles, fence posts, charcoal, and in any situation where the wood needs to be repeatedly exposed to water)
• Plants with a shrub form can provide shelter for wildlife
• Living Trellis – the lower branches can be pruned to allow fruiting vine species a place to grow. The fruiting plant typically then gets a natural boost of nitrogen from the Alder trellis.
• Erosion Control - can be used to protect soil from erosion on steep banks
• Fantastic pioneer species – a plant used to re-establish woodlands on former farmlands or eroded/difficult sites (fixes nitrogen, grows fast, produces lots of leaf litter for soil building, and dies back as other trees shade it out)
• Biomass Production – since Alnus grows so fast
• Dye from bark, shoots, catkins (mainly from Black Alder)
• Tanning – leaves contain high amounts of tannin
• Edible Catkins - raw or cooked, used as an emergency food source (Red Alder)
• Edible Sap – can be used straight or concentrated to a syrup (Red Alder)
• Traditional medicinal uses (primarily bark)

When young most Alders have horizontal patterns to the bark.

http://www.lichen.com/bigphotos/aldersbarelg.jpeg

But as it ages, it gets more thick and fissured.

http://catwarriorworld.webs.com/european_black_alder_bark.jpg

DESIGNING WITH THIS PLANT

USDA Hardiness Zone: See below

AHS Heat Zone: See below (not all species have reliable Heat Zone information)

• Italian Alder (Alnus cordata) – USDA Hardiness Zone 6-9; AHS Heat Zone 9-6
• Black/Common Alder (Alnus glutinosa) – USDA Hardiness Zone 3-7; AHS Heat Zone 3-7
• Gray/Thinleaf Alder (Alnus incana) – USDA Hardiness Zone 2-6; AHS Heat Zone 6-1
• Seaside Alder (Alnus maritime) – USDA Hardiness Zone 7
• Red Alder (Alnus rubra) – USDA Hardiness Zone 4-7; AHS Heat Zone7-1
• Speckled Alder (Alnus incana subspecies rugosa) – USDA Hardiness Zone 2-6
• Smooth/Hazel Alder (Alnus serrulata) – USDA Hardiness Zone 5-8

Chill Requirement: No reliable information available, but as this is not a fruit plant, a chill requirement is not that important.

Plant Type: Medium to Large Tree, Medium to Large Shrub depending on the species

Leaf Type: Deciduous

Forest Garden Use: Canopy Layer, Shrub Layer

Cultivars/Varieties: Many species but very little development

Pollination: By wind. Flowers are monoecious (individual flowers are either male or female, but both can be found on the same plant).

Flowering: Spring, except for Seaside Alder which blooms in the Autumn

Life Span:

Years of Useful Life: Red Alder (Alnus rubra) can live to 100 years. Black/Common Alder (Alnus glutinosa) can live to 150 years

Alder poles being used as both a windbreak and a trellis for peas.

http://www.novascotiapermaculture.net/wp-content/uploads/2009/08/agyalderfencepeas1.jpg

PHYSICAL CHARACTERISTICS OF THIS PLANT

Size:

• Italian Alder (Alnus cordata) – 30-50 feet (9-15 meters) tall and 20-35 (6-10 meters) feet wide
• Black/Common Alder (Alnus glutinosa) – 60-80 feet (18-25 meters) tall and 20-35 feet (6-10 meters) wide
• Gray/Thinleaf Alder (Alnus incana) – 40-60 feet (12-18 meters) tall and 25-40 feet (7-12 meters) wide
• Seaside Alder (Alnus maritime) – 20-30 feet (6-9 meters) tall and wide
• Red Alder (Alnus rubra) – 40-60 feet (12-18 meters) tall and 25-40 feet (7-12 meters) wide
• Speckled Alder (Alnus rugosa) – 20-35 feet (6-11 meters) tall and wide
• Smooth Alder (Alnus serrulata) – 12-20 feet (3.5-6 meters) tall and wide

Roots: Fibrous (Smooth Alder (Alnus serrulata) has suckering roots)

Growth Rate: Fast to Very Fast

Oyster mushrooms growing on a downed Alder log.

Alder can also be innoculated with mushroom spawn to farm your own mushrooms.

http://edibleavenue.files.wordpress.com/2010/10/oyster_log.jpg

GROWING CONDITIONS FOR THIS PLANT

Light: Prefers full sun to light shade

Shade: Tolerates light shade

Moisture: Trees can handle dry soils, but all Alnus species can grow in wet soils

pH: most species prefer fairly neutral soil (5.5-7.5)

Special Considerations for Growing:

Relatively disease and pest free.

Propagation:

Primarily from seed. Hardwood cuttings in Autumn.

Maintenance:

None

Concerns:

None

Windbreak Plants for a Temperate Climate

http://www.chipmackconservation.org/media/pages/windbreak.jpg

Windbreaks are structures used to block, or break the path, of wind. Many things can do this... mountains, hills, rocks, buildings, fences, and plants. The plants are the focus of this article. By using plants as our windbreak, we are have the ability to utilize a Permaculture Principle that encourages multiple functions for each element of design. Our windbreaks have a primary function that is typically one or more of the following:

• Structure protection - blocks cold winds in the winter (lowers heating bill) and drying winds in the summer (lowers evaporation and may protect from forest fires).
• Field protection - blocks wind from blowing too hard over places you would rather have more shelter like a garden near a rocky coast or a tree nursery that may not benefit from high winds
• Livestock shelter - blocks cold and/or wet winds from animals which makes them more comfortable and they need less food calories to maintain body heat
• Livestock fencing - living fences can be more solid and longer lasting (but also more permanent) and can be very effective if using a thorny or very dense growing plant
• Living Snow Fencing - keeps those deep snow drifts on the other side, away from where it may do more damage or cause greater inconvenience (like near a road or barn)

Secondary uses of windbreaks can be:

• Wildlife Habitat - providing some wild food for deer, rabbits, etc. can often keep them on "their" side of the fence and not in our primary food producing areas
• Screening - blocking poor views of neighbors, hosues, or other buildings and/or eyesores
• Noise Suppression - blocking or minimizing noise from a road, neighbors, etc.
• Trespassing Prevention - lining a property with dense growing, thorny plants will make four and two-footed tresspassers think twice about coming on your property

Choosing plants that have additional benefits than just wind blocking increases the usefulness of the windbreak. This is called "stacking functions" and, as mentioned above, it encourages multiple functions for each element of design. Here are some of the additional benefits that plants can offer:

• Edible fruit
• Edible nuts
• Edible other parts - shoots, leaves, flowers, etc.
• Timber
• Pole or Fence wood
• Firewood
• Nitrogen Fixing - the plant puts nitrogen back into the soil and can benefit other plants growing nearby
• Nectar or pollen source for beneficial insects
• Food for wildlife
• Ornamental properties - just plain nice to look at!

WINDBREAK SPECIES
Large Trees  - Over 10 meters (33 feet) tall

1. Italian Alders Alnus cordata - Nitrogen Fixer
2. Red Alders Alnus rubra - Nitrogen Fixer
3. Hackberry Celtis spp. - Edible Fruit, Nectar Source
4. Ash Fraxinus spp. - Timber, Some species have edible manna (sweet, hardened sap)
5. Himalayan Sea Buckthorn Hippophae salicifolia - Nitrogen fixer, Edible Fruit, Nectar Source
6. Eastern Redcedar Juniperus virginiana - Evergreen, Timber
7. Osage Orange Maclura pomifera - Living livestock fence (large thorns), Fence post wood, Fruit is a natural insect repellant
8. Mulberry Morus spp - Wild animal food, Edible Fruit
9. Spruce (Picea spp.) - Can be ornamental, Evergreen, Timber, Edible Tips of New Growth
10. Monterey Pine Pinus radiate - Evergreen, Timber, Paper
11. Corsican Pine Pinus nigra var maritime - Evergreen, Timber
12. Pinyon Pines Pinus spp. in the Ducampopinus Subgenus - Evergreen, Edible Seeds
13. American Sycamore/Buttonwood Platanus occidentalis - Urban shade tree, Edible Sap (can make a syrup)
14. Oak Quercus spp - Timber, Edible Nut
15. Black Locust Robinia pseudoacacia - Nitrogen Fixer, Timber, Firewood, Fence post wood, Edible Seed Pod

Small Trees - Under 10 meters (33 feet) tall

1. Bamboo spp. (Tribe Bambuseae) - Hundreds of species, some Evergreen, Some Edible Shoots, Canes have many uses
2. Redbud Cercis canadensis - Member of the pea family, may be a weak Nitrogen Fixer, Edible Flowers
3. Hawthorns Crataegus spp - Edible Fruit, Nectar Source
4. Sea Buckthorn Hippophae rhamnoides - Nitrogen fixer, Edible Fruit, Nectar Source
5. Crab and Other Apples Malus spp. - Edible Fruit, Nectar Source
6. Pine Trees Pinus spp. - Evergreen, Edible Seeds
7. Cherry Plum Prunus cerasifera - Edible Fruit, Nectar Source
8. Damson / Bullace Prunus insititia - Edible Fruit, Nectar Source
9. Willow Salix spp - Basketry, Nectar Source
10. European Elder Sambucus nigra - Edible Fruit, Edible Flowers
11. Rowans/Whitebeams/Service Trees Sorbus spp. - Some with Edible Fruit

Large Shrubs -  3-8 meters (10-26 feet) tall

1. Alders Alnus spp - Nitrogen Fixer
2. Juneberries Amelanchier spp - Edible Fruit, Nectar Source
3. Strawberry Tree Arbutus unedo - Evergreen, Edible Fruit, Nectar Source
4. Bamboo spp. (Tribe Bambuseae) - Hundreds of species, some Evergreen, Some Edible Shoots, Canes have many uses
5. Barberries Berberis spp. - Some are evergreen, Edible Fruit, Nectar Source
6. Dogwoods Cornus spp. - Edible Fruit
7. Hazels Corylus spp. - Edible Nuts
8. Cotoneaster Cotoneaster spp - Wildlife food source
9. Eleagnus Eleagnus x ebbingei - Evergreen, Nitrogen Fixer, Edible Fruit, Nectar Source
10. Autumn Olive Eleagnus umbellata, Nitrogen Fixer, Edible Fruit, Nectar Source
11. Plum Prunus spp. - Edible Fruit, Nectar Source
12. Arrow Bamboo Pseudosasa japonica - Evergreen, Bamboo shoots/canes
13. Staghorn Sumac Rhus typhina - Edible Fruit, Nectar Source
14. Roses Rosa spp - Edible Fruit, Edible Flowers (great in Salads)
15. Willow Salix spp - Basketry, Nectar Source
16. Elderberries Sambucus spp - Edible Fruit, Edible Flowers
17. Lilac Syringa spp - Ornamental, Nectar Source
18. Nannyberry/Sweet Viburnum Viburnum lentago - Edible Fruit, Nectar Source
19. Highbush Cranberry Viburnum opulus var. americanum - Edible Fruit, Nectar Source

Small Shrubs - Less than 3 meters (10 feet) tall 

1. Green Alder Alnus viridis - Nitrogen Fixer
2. Serviceberry and Shadbush Amelanchier spp. - Edible Fruit, Nectar Source
3. Saskatoon Amelanchier alnifolia - Edible Fruit, Nectar Source
4. Chokeberries Aronia spp.- Edible Fruit, Nectar Source
5. Saltbushes Artiplex spp. - Evergreen, Edible Leaves
6. Barberries Berberis spp. - Some are evergreen, Edible Fruit, Nectar Source
7. Siberian Pea Tree Caragana arboescens - Nitrogen Fixer, Edible Seed, Nectar Source
8. Red Osier Cornus stolonifera - Basketry
9. Hazels Corylus spp. - Edible Nuts
10. Cotoneaster Cotoneaster spp. - Wildlife food source
11. Broom Cytisus scoparius - Nitrogen Fixer, Nectar Source
12. Goumi Eleagnus multiflora - Some are evergreen, Nitrogen Fixer, Edible Fruit, Nectar Source
13. Fever Bush Garrya elliptica - Evergreen
14. Salal Gaultheria shallon - Evergreen, Edible Fruit, Nectar Source
15. Juniper Juniperus communis - Evergreen, Edible Fruit
16. Oregon Grapes Mahonia spp. - Evergreen, Edible Fruit
17. New Zealand Flax Phormium tenax - Fiber, Twine
18. Ninebark Physocarpus spp. - Erosion Control, Nectar Source
19. Trifoliate Orange Poncirus trifoliate - Edible Fruit
20. Nanking Cherry Prunus tomentosa - Edible Fruit
21. Currants Ribes spp. - Edible Fruit, Leaves (tea)
22. Roses Rosa spp. - Edible Fruit, Edible Flowers (great in salads)
23. Chinese Bramble Rubus tricolor - Evergreen, Edible Fruit, Groundcover
24. Willow Salix spp. - Basketry, Nectar  Source
25. Snowberries Symphoricarpos spp - Nectar Source
26. Gorse Ulex europaeus - Nitrogen Fixer, Nectar Source

Vines

1. Honeysuckle Lonicera spp. - Edible Fruit, Wood for tools and crafts, Nectar Source
2. Roses Rosa spp. - Edible Fruit, Edible Flowers (great in salads)
3. Blackberry Rubus fruticosus - Edible Fruit, Nectar Source
4. Chinese Bramble Rubus tricolor - Evergreen, Edible Fruit, Groundcover

I'll update this article, and lists, from time to time as I get more research completed.