“So tell me, how old is that tree?” must be one of the most commonly asked questions by visitors to the Geelong Botanic Gardens; right after “where are the toilets?” It is also one of the most difficult to answer since, for most trees, the real answer is “I don’t know” – but with a bit of work we could find out.
Method 1: Chop down the tree and count the tree rings
Any child could tell you this and I am told that it is a remarkably accurate method. You will almost certainly get an accurate idea of how old he tree was, and an even more accurate date for the day it wasn’t.
This is a 1500 year old dead tree showing a slice through a Sequoiadendron gigantium showing significant dates in human history from St Columba founding a mission on Iona to Charles Darwin all lined up to the tree rings.
However, most chopped down trees look more like this
Counting tree rings on a bit of rough sawn wood is not quite as easy as it sounds. Never the less, in the interests of science, I thought I’d give it a go on a tree removed in January. Tree age = 70 years
Is that reasonable? How do we know?
My guess is that 70 might be a bit old – by perhaps by 5 years (based on the age of the property). But then again, I don’t know how old the sapling tree was when it was planted – and it could have been 5 years old by then too. A bit more information would help with verification.
Which brings us to the next method…
Method 2: Check the (formal) records
In a Botanic Garden, you might have thought that this would be a shoe in. It’s not. The Geelong Gardens, like many others, have very patchy planting records. We know what our first curator, Daniel Bunce had planted by January 1860, less than 3 years after the Gardens commenced, because he published a catalogue of Plants under Cultivation in the Botanical Gardens Geelong . After that, with the exception of our own Seq
uoiadendron gigantium, we really don’t have records until the last 20-30 years.
If you’re lucky, the tree you are interested in will have a sign noting the date and name of the august personage who planted the tree, after that, you are on your own.
But experienced gardeners and botanists must have some idea of how old the trees are – right?
Method 3: Ask an expert gardener
This sounds great – until you ask more than one expert.
The row of Bunya Bunya pines (Araucaria bidwillii) which line the south-western edge of the original nursery garden are a good example. These trees are listed on the National Trust significant tree register. The current listing no longer gives an age (smart people), but the original listing in 1989 suggests a planting date around 1885 for the stand of bunyas.
On the other hand, fanfare around the Association of Friends of Botanic Gardens conference (2001) (Bunce, Bunyas and Beyond) makes a clear link between the bunyas and the first curator Daniel Bunce (d 1872). The reasons for this link are beyond the scope of this post (but make an interesting story all on their own. One to keep up my sleeve). An article in the Geelong Advertiser Weekend Magazine (36/6/2001) makes it clear that the prevailing opinion at that time was that Bunce planted the bunyas, the ginkgo and the Chilean wine palm.
So who is right – if any of them?
Now if you’d asked me, I’d have said that there is no evidence that these trees were planted in the 19th Century – but how would I know?
Method 4: search for references to your chosen tree in the written record
Unfortunately, there are very few actual written records for the Geelong Botanic Gardens. (There was something about a flood in the council document storage facility?) Anyway, very little exist, except for the Bunce catalogue of 1860. No Bunyas are listed there.
But there are other secondary records such as old newspapers and magazines which might shed some light on the matter.
Searching newspapers has become easier with the advent of computers, the internet and more recently, the Australian National Library’s Trove project to digitise (and translate into text) Australia’s newspapers.
In the interest of research, I have spent many late nights “troving” in order to answer just that question: how old are these trees?
Fortunately for us, there are a number of excellent descriptions of the Geelong Botanic (or Botanical) Gardens from the very early days of the Gardens through to the 1910s. Many of these list the botanical highlights, though to be honest, these are frequently the massed plantings of brightly coloured garden ornamentals. From these records we know that by 1897, the ginkgo was 30 ft high and that the Chilean wine palm (Jubaea chilensis) was fully 30 years old with the shed (Raddenberry fern house) built over it. The implication from these reports is that both of these trees were indeed planted by Bunce in the 1860s.
There is no mention at all of any bunya bunya pines up to 1926 (the end of the current phase of digitization for the Geelong Advertiser).
But not everything gets mentioned in an article about gardening, so perhaps the writers were less impressed by an Australian native tree than they were about such exotic trees as the ginkgo and the Jubaea.
What, you may ask (and I hope you did) makes me think there is some doubt about the age of the bunyas?
The answer is in…
Method 5: check the old photographs
(Those taking this route should take caution – most of the photos don’t have dates, although there are clues which help narrow them down. This too, is outside the scope of the current post)
This is one of the earliest photographs of the Raddenberry fernery which occupied the middle of the original Nursery Garden from 1885.
It is this image which got me started in the first place, because if the bunyas were planted by Bunce, then they should be clearly evident as a line of trees in the foreground of this photo. But the only trees here are clearly young pine trees. (Young bunyas have dome shaped crowns, compared with the classic Christmas tree shape of pine trees).
So let’s look at another image, this time from the early 20th Century.
This photograph looks back across the Gardens from near the Sequoiadendron. The Raddenberry fernery is on the left and the entrance to the Nursery Garden on the right. By the estimation of “experts”, the bunyas should be between 25 and 40 years old – plenty big enough to dominate the western sky line – but they aren’t there. Once again, just pine trees which are probably the grown-up versions of the ones in the previous photograph.
By 1930, there are the first aerial views of the gardens. This image looks across the gardens to the west with the now rather dilapidated fernery in the centre. The arrows show where the line of bunyas would be (on the western boundary) – but still they aren’t there!
It is not until this aerial photo from 1947, that a line of trees (indicated by arrows) which could actually be the bunyas is visible on the western boundary.
So how old is that tree?
For the stand of bunyas (Araucaria bidwillii) on the western boundary of the old nursery garden – not as old as you might think. Probably around 85 years in 2016.