Plant Life: Enduring leafy giant recalls royal occasion

The Royal Oak. Photo by Linda Robertson.
The Royal Oak. Photo by Linda Robertson.
Nearly 147 years ago, on March 10, 1863, a most royal wedding was celebrated in England.

The wedding in question was the marriage of the Prince of Wales to the Danish Princess Alexandra. The good news filtered through to the colony at the lightning speed of the day, reaching Dunedin three months later.

To mark the special occasion - and in conjunction with the establishment of the Botanic Garden on the site of today's University of Otago - a substantial portion of the city's population gathered on a sunny winter's day, June 30, 1863.

Two commemorative oaks, dubbed The Royal Oaks, were duly planted.

Location, location, location Early Dunedin was plagued by floods from the Water of Leith and, in February 1868, flooding caused severe damage.

Three city bridges and an entire acre of landscaped land in the Botanic Garden was washed away, including one of the Royal Oaks.

The garden was relocated to its present site that year, along with the precious remaining oak.

It stands sentinel over the children's playground today, dominating the scene with its massive trunk and broad, irregular crown.

Cables were installed in the canopy in 1980 to increase support to the branch structure.

After 30 years of wear the tensioning became incorrect, so last year 20% of the outer canopy was thinned and a new web of nylon cables installed.

However, soon afterwards an unusually strong storm caused a large limb to crack.

An arborist reduced its length and the tree is healing well.

The Royal Oak stands 12m tall, has a trunk circumference of 5.6m and diameter at breast height of 1.78m.

The original plaque at the base of The Royal Oak acknowledges John Hyde Harris Esq, in 1863, for planting the young saplings all those years ago.

Common oak, Quercus robur, can live for about 250 years.

The Latin word robur means strength or hard timber.

Also known as English oak or pedunculate oak, Quercus robur is a member of the beech family, Fagaceae.

Marianne Groothuis is camellia and theme collection curator at the Dunedin Botanic Garden.