A BLAZE swept across Chobham Common on April 12, killing thousands of rare birds and small animals.
The fire, which burned about 50 acres, was believed to be arson.
The M3 was closed in both directions for five hours, causing traffic chaos in nearby towns.
Camberley came to a complete standstill, with vehicles jamming the A30 trying to seek an alternative route into London.
Traffic snarled up on the M3, with 25-mile tailbacks.
Visibility was down to zero in places as smoke swept across the carriageways. The M25 was also badly affected.
Fire crews from Hampshire, London and Berkshire joined their Surrey counterparts in tackling the blaze, which took more than five hours.
Countryside ranger Andy Wragg said: "The fire started at about midday on Friday. I was working on another part of the common when I saw it, although I think people on the motorway had seen it first.
"I was with the fire investigation officer on Saturday and we think it was deliberate arson. It has all the hallmarks of an arson.
"Whoever has done this is an extremely irresponsible and dangerous person who has not only caused the loss of hundreds of birds and animals but is also putting people's lives at risk.
"The three definite starting points were between the M3 and the Chertsey Road. It has wiped out some of the rarest birds in the country, including Dartford warblers which had young.
"The area was a quiet haven for wildlife which is why it was the ideal place for them to live. We are working incredibly long hours to deal with this, but it is a very serious fire over some of the best, least disturbed heathland.
"We'll have to wait and see what happens in terms of recovery. The fire didn't burn very deeply into the ground so the heather has survived, but the area will need heavy management to get it back to heathland.
"The huge blocks of gorse next to the M3 are the recipe for disaster. Unlike heather and grass it is impossible to fight in terms of fire and it is a major threat to people using the M3."
Mr Wragg warned people to be vigilant when using the common and said people acting suspiciously should be reported to the police, or to him.