The fate of a 400-year-old tree has been in the balance but road chiefs have promised to reassess the oak's root system with high-tech investigations.
It was feared that the huge 'Three Oaks' tree in Station Road, Higham Ferrers may become a danger if its roots systems were damaged by upcoming Chowns Mill road works nearby.
But, using ground-penetrating radar and trial holes, environmental specialists will now locate roots to find out if they will be uncovered when the road level is lowered.
Justina Bryan who founded the Save Our Oak campaign group said: "It's a positive move in the right direction. When I first started to contact them about the tree the answer was 'no', the tree was going.
"Now at least they are checking it and doing the tests. They are aware of the tree and fingers crossed they will find a solution."
The tests, which will not damage the tree in any way, include ground penetrating radar to 'X-ray' the existing ground to locate tree roots and trial holes using a vacuum excavator to leave the root system undamaged.
To ensure minimum disruption, the trial holes will take place in early March when the A5028 Station Road, Higham Ferrers, is closed as part of the £24m Chowns Mill junction improvements scheme.
The new road layout will fall within 1.5m of the oak tree and the road will be lowered, to a construction depth of 2m from the existing ground level.
Project manager Dean Holloway said: “Highways England only cuts back or fells trees where is it essential to keep people safe or to allow us to improve journeys. But we understand that people are concerned about the potential loss of this oak tree.
“Therefore we are making sure every option is fully explored to see if we can retain the tree whilst still ensuring safety, which is always our number one priority. Extensive investigations will be taking place over the next couple of months to see if we can achieve that goal."
A spokesman for Highways England added: "The new road layout has been designed to current road design standards and reducing its width could threaten the safety of road users. Keeping the tree would prevent a footway being installed but consideration is being given to whether this could be re-routed.
"A final decision on the future of the tree will only be made after the tests have been concluded.
"Highways England takes its environmental responsibilities very seriously and we are one of the largest tree planting organisations in the UK."
More than 4,000 people have signed the Save Our Tree petition.
Campaigners will gather under the tree this Sunday, January 26, to show their support .
Mrs Bryan said: "It's all about keeping up the pressure and I'd like to get as many signatures as possible."
For more information about the Chowns Mill improvement project click here.