Foreign Invaders

The stories of five Frankenstein plants which have invaded foreign shores causing massive ecological and economic damage.

Innocuous plants, which cause no problems in their natural habitat, can become major menaces when released into the wild in the UK.

A Rhododendron, introduced from the Black Sea area, is now choking native habitat from hundreds of thousands of acres of land in Wales and costing the National Trust a fortune to control.

It's a battle they are losing.

Episodes

EpisodeTitleFirst
Broadcast
RepeatedComments
20050117

The story of five plants which have invaded foreign shores causing massive ecological and economic damage. It is a story of invasion by stealth; plants that have invaded our shores and now threaten our coasts, clog our rivers, colonise our commons and take over our gardens.

1/5. Tony Russell reports on the menace of Japanese Knotweed. It was a much-prized plant introduced by the Victorians but it's now estimated it will cost more that £1.5 billion to eradicate from these shores.

20050118

The story of five plants which have invaded foreign shores causing massive ecological and economic damage. It is a story of invasion by stealth; plants that have invaded our shores and now threaten our coasts, clog our rivers, colonise our commons and take over our gardens.

2/5. Tony Russell discovers why a single goldfish is blamed for drying up a three hectare lake and causing damage put at millions of pounds. It's the remarkable story of the pond weed Crassula Helmsii.

20050119

The story of five plants which have invaded foreign shores causing massive ecological and economic damage. It is a story of invasion by stealth; plants that have invaded our shores and now threaten our coasts, clog our rivers, colonise our commons and take over our gardens.

3/5. Tony Russell reports on a plant that is marching across Snowdonia, is colonizing vast tracts of Scotland and has even invaded Kew Gardens. Rhododendron ponticum was imported by the Victorians, won prizes at garden shows but is now devastating thousands of acres of important countryside.

20050120

The story of five plants which have invaded foreign shores causing massive ecological and economic damage. It is a story of invasion by stealth; plants that have invaded our shores and now threaten our coasts, clog our rivers, colonise our commons and take over our gardens.

Tony Russell reports on how a grass, Spartina, suffered a freak genetic change, crossed the Atlantic and is now causing havoc in the United States.

20050121

The story of five plants which have invaded foreign shores causing massive ecological and economic damage. It is a story of invasion by stealth; plants that have invaded our shores and now threaten our coasts, clog our rivers, colonise our commons and take over our gardens.

Tony Russell explains why poor quarantine procedures in France allowed an aggressive Japanese seaweed, Sargassum Muticum, to cross the Channel and invade waterways from the Solent to the Norwegian Fjords.

01Japanese Knotweed2004030720050117

The stories of five Frankenstein plants which have invaded foreign shores causing massive ecological and economic damage.

Innocuous plants, which cause no problems in their natural habitat, can become major menaces when released into the wild in the UK.

A Rhododendron, introduced from the Black Sea area, is now choking native habitat from hundreds of thousands of acres of land in Wales and costing the National Trust a fortune to control.

It's a battle they are losing.Japanese Knotweed knows no boundaries and takes over vast tracks of land creating an impenetrable bamboo-like wall.

Even the sea is under attack.

Japweed came to the UK as tiny filaments attached to oysters bought in France and is now choking British estuaries.

But it's not a one-way traffic.

English cord-grass, not a problem in the UK, is fouling up rivers and estuaries in New Zealand and North America where the conditions and lack of natural predators allow it to grow unchecked.

Tony Russell, one of the Gardeners' Question Time panellists, looks at the battle to repel the foreign invaders and counts the cost of the war for which there are no weapons of mass destruction.

01Japanese Knotweed2004030720050117

The stories of five Frankenstein plants which have invaded foreign shores causing massive ecological and economic damage.

Innocuous plants, which cause no problems in their natural habitat, can become major menaces when released into the wild in the UK.

A Rhododendron, introduced from the Black Sea area, is now choking native habitat from hundreds of thousands of acres of land in Wales and costing the National Trust a fortune to control.

It's a battle they are losing.Japanese Knotweed knows no boundaries and takes over vast tracks of land creating an impenetrable bamboo-like wall.

Even the sea is under attack.

Japweed came to the UK as tiny filaments attached to oysters bought in France and is now choking British estuaries.

But it's not a one-way traffic.

English cord-grass, not a problem in the UK, is fouling up rivers and estuaries in New Zealand and North America where the conditions and lack of natural predators allow it to grow unchecked.

Tony Russell, one of the Gardeners' Question Time panellists, looks at the battle to repel the foreign invaders and counts the cost of the war for which there are no weapons of mass destruction.

02Crassula Helmsii2004031420050118

Tony Russell discovers why a single goldfish is blamed for drying up a three hectare lake and causing damage put at millions of pounds.

It's the remarkable story of the pond weed Crassula Helmsii.

02Crassula Helmsii2004031420050118

Tony Russell discovers why a single goldfish is blamed for drying up a three hectare lake and causing damage put at millions of pounds.

It's the remarkable story of the pond weed Crassula Helmsii.

03Rhododendron Ponticum2004032120050119

In this edition Tony Russell reports on a plant that is marching across Snowdonia, is colonising vast tracts of Scotland and has even invaded Kew Gardens.

Rhododendron ponticum was imported by the Victorians, won prizes at garden shows but is now devastating thousands of acres of important countryside.

03Rhododendron Ponticum2004032120050119

In this edition Tony Russell reports on a plant that is marching across Snowdonia, is colonising vast tracts of Scotland and has even invaded Kew Gardens.

Rhododendron ponticum was imported by the Victorians, won prizes at garden shows but is now devastating thousands of acres of important countryside.

04Spartina2004032820050120

Tony Russell reports on how a grass, Spartina, suffered a freak genetic change, crossed the Atlantic and is now causing havoc in the United States.

04Spartina2004032820050120

Tony Russell reports on how a grass, Spartina, suffered a freak genetic change, crossed the Atlantic and is now causing havoc in the United States.

05 LASTSargassum Muticum2004040420050121

Tony Russell explains why poor quarantine procedures in France allowed an aggressive Japanese seaweed, Sargassum Muticum, to cross the Channel and invade waterways from the Solent to the Norwegian Fjords.

05 LASTSargassum Muticum2004040420050121

Tony Russell explains why poor quarantine procedures in France allowed an aggressive Japanese seaweed, Sargassum Muticum, to cross the Channel and invade waterways from the Solent to the Norwegian Fjords.