The health of the Kvill oak, Sweden's oldest known oak tree, has greatly deteriorated in recent years, the national SVT broadcaster reported.
Last year, a single green twig was the strongest, if not the only sign of life from the historical giant, which is a major local attraction.
"Should the twig ever become green again, it will probably happen during the second half of way", Kalmar County natural reserve manager said.
However, he sees the death of the millennial tree as imminent.
"Sure, it feels sad, but we have no more aces up our sleeve. Now, the oak has to live the rest of its life in peace as long as it can bear".
So far, many international experts, including from Germany and the UK, have participated in efforts to save the tree.
"The UK, which has a lot of very old trees, is in the lead. But this task is incredibly difficult even for experienced arborists", Svensson explained.
The Kvill oak, also known as the Rumskulla oak, is situated in Kalmar County in the historic province of Småland. First described in 1772, it is the oldest oak in Sweden and one of the largest trees in Scandinavia.
In the 1930s, the Kvill oak was established to be about 950 years old and has thus passed the 1,000-year mark now.
However, the past decades have been especially tough for the green giant. In the 1960s a cohesive iron band was put around the trunk, seemingly negatively affecting the flow of nutrients within in. The iron band was cut in 2005, only to be replaced.
"When the supportive band was put back, it was probably done too hard", Svensson explained. "The tree became stressed and began to strangle itself".
A few years later, the tree was affected by the green oak moth, butterfly larvae, and mildew.
The oak is a major tourist attraction, standing tall on a meadow outside Vimmerby, and is referenced in tourist guides as Sweden's oldest tree and the largest in circumference, at 14 metres.
"The oak will die but I can't say if this happens this year or later", Svensson said his diagnosis.
