Relict trees

Relict trees

RelictThey are species or ancient evolutionary lines that have survived from past geological eras, when the Earth's climate and vegetation were different. In colloquial speech, they are often calledliving fossils, although this expression is conditional: modern trees continue to evolve and are not exact copies of their fossil ancestors.

Relic trees are valuable as:

genetic memory of the planet;

material for scientific research;

reserve of resistance to climate change;

the basis of arboretums and educational forests;

a symbol of longevity and continuity of life.

However, ancient origins do not mean that a species is automatically better than native trees or suitable for mass reforestation.

Main relict trees

1. Ginkgo is the city's main relict tree.

Ginkgo biloba— the only living representative of the ancient lineage of ginkgoes. It is so evolutionarily distinct that it has no close modern relatives. In the wild, the species is considered endangered, although it is widely cultivated throughout the world.Plants of the World Online)

Unique properties

fan-shaped leaves with unusual venation;

high resistance to air pollution;

tolerance to urban heat and compacted soils;

low susceptibility to many pests;

durability - hundreds and potentially more than a thousand years;

bright golden autumn colouring.

Flaws

weak ecological connection with European insects;

slow growth in youth;

female trees produce seeds with a strong-smelling fleshy shell;

does not create a full-fledged replacement for the local forest.

Best use:city ​​alleys, educational park, collection sector, single symbolic trees.

2. Metasequoia – a tree “returned from the fossils”

Metasequoia was first described from fossil remains. Living trees were discovered in China in the 1940s, after which the seeds were distributed to botanical gardens around the world.

This is a coniferous tree thatsheds its needles for the winter.

Advantages

rapid growth;

tolerates frosts of Central Europe;

loves fresh and moist soils;

tolerates short-term flooding well;

forms a beautiful straight trunk;

soft needles turn copper-red in autumn;

can live for several centuries.

Flaws

suffers on dry, shallow soils;

requires a lot of space;

Surface roots can lift the road surface;

should not be planted near foundations and narrow paths.

Best place:pond bank, damp meadow, valley, lower part of slope.

3. Wollemi is one of the rarest trees in the world.

Wollemia nobiliswas discovered in Australia in 1994. Its natural population is extremely small and restricted to a small area. The species has a critical conservation status.springermedizin.de)

Unique features

unusual blistered bark;

several trunks can rise from one root system;

simultaneously forms male and female cones;

belongs to the ancient family Araucariaceae;

has enormous conservation and scientific value.

For Switzerland

Possible cultivation:

in a protected courtyard;

near a warm wall;

in a large container;

in the greenhouse;

in mild areas without severe frosts.

This is not a forest-forming tree in Switzerland, but a collector's tree. Young plants need to be protected from severe frost, winter winds, and excessive moisture.

4. Chilean Araucaria

Araucaria araucana, also known as the "monkey tree," is native to Chile and Argentina. It is dioecious: male and female cones typically develop on separate plants.

Advantages

very unusual architectural appearance;

durability;

dense leathery leaves;

large edible seeds;

wind resistance after rooting;

high cultural value for the indigenous peoples of South America.

Flaws

sharp leaves;

slow growth;

requires a mild, humid climate;

sensitive to stagnant water;

To obtain seeds, a male and female tree are needed;

Falling mature cones require a clear area.

In Switzerland, it is best grown in a sheltered but not too hot area.

5. Giant Sequoiadendron

Giant sequoia— one of the most massive and durable trees in the world.

Advantages

huge reserves of woody biomass and carbon;

thick bark;

durability of several thousand years in the natural habitat;

high decorative and educational value;

grows well in many areas of Central Europe;

young trees grow quite quickly.

Flaws

giant adult sizes;

requires deep soil and plenty of space;

not suitable for small areas;

the summit can be damaged by lightning and drought;

does not ecologically replace local European breeds.

The minimum reasonable distance from the building is approximately 15–20 m, and for free development even more is desirable.

6. Evergreen sequoia

Sequoia evergreen— the tallest modern tree, but much more demanding of air humidity than the sequoiadendron.

Best conditions:

mild winter;

high air humidity;

sufficient summer precipitation;

deep fresh soil;

protection from dry wind.

For most of Switzerland, the sequoiadendron is more reliable. The evergreen sequoia is attractive for mild lake areas and experimental plantings.

7. Bald cypress - a coniferous tree for water

Taxodium distichumNative to swampy areas of North America, it sheds its needles in the fall, like the metasequoia.

Peculiarity

On constantly moist soil it is capable of creating structures protruding above the ground -pneumatophores, or "breathing knees."

Application

swampy lowland;

shore of a reservoir;

floodplain;

area subject to seasonal flooding;

water purification and retention system.

Restrictions

not needed on a normal dry area;

requires a lot of space;

respiratory roots may obstruct passage;

alien to the European natural floodplain.

Alder, willow, poplar, and European white elm are preferred for natural regeneration. Taxodium is best reserved for the water park or experimental sector.

8. Yew berry - a European relic

Taxus baccataIt is considered a tertiary relic and is one of the longest-lived trees in Europe. It can grow under the canopy of oak, beech, linden and other species.MDPI)

Advantages

exceptional shade tolerance;

durability;

evergreen crown;

ability to renew after severe pruning;

valuable shelters for birds;

strong elastic wood;

a local species for Switzerland.

The main drawback

Almost all parts of the tree are toxic, except for the red, fleshy seed coat. The seed itself is also poisonous. Yew trees should not be planted where their branches are accessible to horses and livestock.

For a mixed forest, this is one of the most valuable relict species, but its share should usually be small - approximately1–5%, local groups.

9. European stone pine as a glacial relic

Pinus cembra— a relict high-mountain species that survived in the Alps and Carpathians after the ice ages. It grows at the upper tree line, withstands very severe frosts, and produces edible seeds that are dispersed by the nutcracker.EUFORGEN)

Meaning

strengthens mountain slopes;

protects soil and snow cover;

feeds birds and small animals;

forms a long-lasting mountain forest;

produces aromatic wood;

is an indigenous genetic resource of Switzerland. (EUFORGEN)

It can grow in the lowlands, but its true ecological niche is cool mountain conditions.

10. Umbrella pine

Sciadopitys verticillatafrom Japan - the only modern representative of the Sciadopityaceae family.

Its "needles" are botanically unusual: the green elements, resembling thick double needles, have a special origin and are arranged in whorls, like the spokes of an umbrella.

Application

shady or semi-shady arboretum;

Japanese garden;

protected wet area;

collection of ancient gymnosperms.

It grows slowly and does not like dry, chalky soil or cold, drying wind.

Relict deciduous trees

Not only conifers can be relict.

Caucasian zelkova

Zelkova carpinifolia— an ancient relative of elms, preserved in the Caucasus region.

Advantages:

powerful crown;

durability;

good regeneration of shoots;

heat resistance after rooting;

valuable wood;

It is not affected by Dutch elm disease in the same way as true elms.

Flaws:

requires space;

young trees are sensitive to severe frost;

is not a native breed of Switzerland.

It is especially interesting as a functional analogue of elm for collection and climate testing.

Davidia involucrum

Davidia involucrata— a Chinese relic tree known for its white bracts that look like scarves or wings.

Her role is primarily:

decorative;

educational;

collectible;

support for insects during flowering.

It prefers deep, fresh, humus soils and a protected position.

Oriental plane tree

Oriental plane treepreserved in the river valleys of the Eastern Mediterranean and Western Asia.

Advantages:

powerful root system;

heat tolerance;

durability;

ability to grow near water;

wide shadow;

resistance to pruning.

Flaws:

a huge tree;

roots can damage coverings;

Leaves and bark may irritate the respiratory tract of sensitive people;

requires control of plane tree diseases.

Relic trees by function

Which relict species are suitable for the DREVO forest?

The first group can be included in the forest system

Yew berry— shady local coniferous layer.

European stone pine- mining and food sector.

Metasequoia- damp meadows and ponds.

Cedar of Lebanon- open drained areas.

Atlas cedar- experimental dry slopes.

Caucasian zelkova- collectible warm areas.

Ginkgo- forest edges, paths and educational areas.

Sequoiadendron- single monumental trees.

The second group is for collection only

Wollemia;

umbrella pine;

Chilean Araucaria;

Davidia;

Chinese Cathaya;

rare zelkova;

cryptomeria;

Sequoia evergreen.

It is better to place them in a controlled environment.dendrological park, and not freely mixed with natural forest.

The concept of the "Relict Grove DREVO"

A separate living exhibition could be created showing the history of trees.

Zone 1. Ancient gymnosperms

ginkgo;

araucaria;

Wollemia;

umbrella pine.

Zone 2. Ancient redwoods

metasequoia;

sequoiadendron;

sequoia;

swamp cypress.

Zone 3. European relics

thousand;

European stone pine;

juniper;

separate ancient genetic lines of oak and beech.

Zone 4. Mediterranean and mountain relics

Cedar of Lebanon;

Atlas cedar;

Araucaria chilensis as a South American analogue;

oriental plane tree;

Liquidambar orientalis.

Zone 5. Relict deciduous trees

Caucasian zelkova;

Davidia;

ginkgo;

rare rowan trees;

wild fruits of ancient European populations.

Practical ratio

In a typical natural restoration forest, it is reasonable to limit exotic relict trees to approximately1–5% of the total populationLocal relics—yew and alpine cedar—can be used more widely where conditions match their natural ecology.

The main value of the relic grove is not the timber harvesting, butpreserving genetic diversity, education, scientific observation, and creating a living archive of Earth's history.