Native Flashcards
Where is Alder’s natural habitat?
- Rivers
- Ponds
- Lakes
- Marshes and cool damp areas
- Wet woodland and streams
Where does Frangula Alnus grow best?
- Wet soils
- Open woods
- -Thriving in scrubs
- Hedgerows
- Wet heathland
- Riverbanks and Bogs
How do you identify Alnus Glutinosa in Winter?
Female catkins and purple twigs have orange markings (lenticels)
Why is the Alder tree feared or thought unlucky?
- When cut, the pale wood turns deep orange, giving the impression of bleeding.
- As such, many people feared alder trees and the Irish thought it was unlucky to pass one on a journey.
What fungus have alder tree’s been infected by in the UK?
Phytophthora (Common to broadleaf species)
- Thought to be uncommon on alder until the discovery of a new hybrid strain, which causes root root and stem lesions.
What do Alder’s roots help to do?
Prevent soil erosion
When does Alder buckthorns flowers appear?
-May to June in clusters in the leaf axils.
How many species of the the genus Alnus are native the UK?
One. Alnus Glutinosa
Where else is Alder found other than the Britain?
From Europe to Siberia
What are small brown cones that stay on the Alder tree all year around?
Female catkins
Historically, how has Alder been used?
- Construction of boats (withstands rot under water)
- Sluice gates and water pipes (Much of venice is built on Alder pipes)
- These days, Alders is used to make timber veneers, pulp and plywood.
What is the average height of a mature Alnus Glutinosa?
20 metres
What do the Alder’s male catkins look like?
Yellow and pendulous, measuring 2-6cm
Alder’s are monoecious. What does this mean?
Both male and female flowers are found on the same tree.
What other common names can Alder go by?
Common Alder, Black Alder, European Alder
What animal and insect species does the Alder tree support?
- Caterpillars (Food)
- Moths including the alder kitten, pebble hook-tip, te autumnal and the blue bordered carpet moth.
- Source of nectar for bees
- Seeds are eaten by the siskin, redpoll and goldfinch
What shape are alder trees?
Conical
What is the latin name for Alder Buckthorn?
Frangula Alnus
Is Alder Buckthorn related to Alder?
No, It is a colourful tree native to England and Wales, most of Europe, northern Africa and western Asia.
Where is Frankia Alni found in the native species Alnus Glutinosa?
The root nodules
Why does Alder improves the fertility of the soil?
- The bacterium Frankia alni absorbs nitrogen from the air and makes it available to the tree.
- Alder, in turn, provides the bacterium with sugars, which it produces through photosynthesis.
How does the Alder Buckthorn reproduce?
It is hermaphrodite, meaning that male and female reproductive parts are contained within the name flower.
What are the twigs like of an Alnus Glutinosa?
- Light brown spotted stem which turns red towards the top.
- Young twigs are sticky to the touch.
What threats or pest are associated with Alder Buckthorn?
None
How is Alder Buckthorn used?
- Various dye’s
- Charcoal is prized in the manufacture of gunpower
- Horticultural value as an informal hedge.
- The wood has been used to make wooden nails and shoe lasts.
How are Alder’s pollinated?
By the wind
What is the bark like of an Alder Tree
- Dark is fissured
- Often covered in lichen
How does Frangula Alnus benefit wildlife?
- Food plant of the brimstone butterfly whose caterpillars eat the leaves.
- It’s flowers provide a source of pollen and nectar for bees and other insects, and it’s berries are eaten by birds.
What do the Alder’s female catkins look like?
- Green and oval-shaped
- Grouped in numbers of three to eight on each stalk
How can you diagnose alder dieback?
- In summer, leaves are abnormally small and yellow, and often fall prematurely
- Infected trees have dead twigs and branches in the crown.
- They may also bear an unusually large number of cones- a sign of stress
- Sometimes the trees die rapidly, sometimes they deteriorate gradually.
- Bleeding from the bark (brown rusty spots)
Does Alder coppice well?
Yes, and the wood makes excellent charcoal and gunpowder.
What kind of soil does Frangula Alnus grow in?
It prefers acidic soils but can grow on neutral soils as well.
What are leaves like on an Alnus Glutinosa?
- Purple or grey leaf buds form on long stems
- 3-9cm long dark green leaves are racquet-saped and leathery, with serrated edges
- The leaf tip is never pointed and is often indented
What does a pollinated female catkin look like?
- Woody and appear as tiny cone-like fruits in winter
- They open up to release seeds, which are dispersed by wind and water
What has Alder got do with Robin Hood?
The green dye from the flowers was used to colour the clothes and also thought to colour the clothes of fairies
How long do Alder’s usually live?
60 years
Where are the Alnus species distributed?
Throught the North Temperate zone and in North, Central and South America.
What colour is the bark of Alder Buckthorn?
-Outer bark is dark brown but the innber barkis bright yellow when exposed.
How tall can mature Alder Buckthorn grow to?
6m
How is Frangula Alnus identified in winter?
- Buds do not have scales and are hairy.
- Peeling back the bark surface reveals yellow bark underneath.
Why is Alder a good tree for the successional species that follow?
It helps provide additional nitrogen
What can Alder Buckthorn be confused with?
- Cornus Sanguinea (Dogwood) which is not spiny.
- Rhamnus Cathartica (Purging Buckthorn) which has oppostite as opposed to alternate leaves.
Alder is noted for its important symbiotic relationship with which nitrogen-fixing bacterium?
Frankia alni
Can Alder grow in nutrient-poor soil?
Yes. Because of it’s association with nitrogen-fixing bacterium Franki alni. it can grow where few other tree’s thrive.
What are the twigs like of an Alder Buckthorn?
- Smooth and thornless and straight.
- Purple-brown in colour with fine white streaks.
What are th leaves like on an Alder Buckthorn?
- Matt green
- Oval
- 3-7cm long and slightly hairy.
- They have a rounded tip but are tapered toward the stalk.
When dos Alnus Glutinosa Flower?
Between February and April
Does Alder Buckthorn produce fruits?
Yes. Once pollinated by insects, the flowers develop into a small berry, which ripens from green to red in late summer, eventually to a dark purple or black in early autumn.
How many species are there in the genus Alnus?
20 to 30
What do the flowers of an Alder Buckthorn look like?
- Star shaped
- 3-5mm diameter
- 5 greenish-white triangular petals.
Why can the Alnus Glutinosa be confused with Corylus avellana?
The rounded leaf shapes are similar however hazel leaves are softly hairy compared to te shiny ones of alder.
What is the Latin name of Alder?
Alnus Glutinosa
Where are tree’s used to improve soil fertility?
- Former industrial wasteland and brownfied sites.
- They are also used in flood mitigation.
Alder naturally prefers damp locations but where else can it occur?
- Drier locations
- Mixed Woodland
- Forest Edges
