Steve Alton is exploring some of the least accessible places on earth to save rare plants from extinction.

Steve is the overseas territories specialist at the Millennium Seed Bank, Ardingly.

He is visiting Ascension Island and the Falkland Islands to help conserve indigenous species.

The islands, plus St Helena, which he plans to visit later in the year, are home to a number of unique plants.

Steve is helping the islanders learn to harvest seeds properly so they can be stored and kept safe at Ardingly.

Roger Smith, head of the seed bank, said: "There are 13 species in the Falklands which occur nowhere else in the world.

"If these are lost, they are lost from the world.

"Ascension Island has six endemic species and another 19 considered to be a conservation priority.

"The distances between these overseas territories are too large for seeds to move from one to the other so the plants have evolved to be highly adapted to their environments.

"Because of human development, these things are at risk.

"Wild habitats have been converted to agriculture - the introduction of sheep on the Falkland Islands, for instance - and people have reduced the area available for plant species."

Steve is making a three-week trip to the South Atlantic.

Plants thought to be most at risk in the Falklands include the Felton's flower, Antarctic cudweed, hairy daisy and false plantain.

Mr Smith said: "If global warming exists and they need lower temperatures to flower, they may not be getting the atmosphere they need."

The seeds can be revived at Ardingly and sent back to be reintroduced into the wild.

Steve has enjoyed seeing far-flung parts of the world but it has not all been fun.

Mr Smith said: "Steve has been to the British Virgin Islands, where he has done the training, and he may go back again later.

"But he was eaten by mosquitoes, so it's not the cushy number most of us would like to think."