Casuarina & Allocasuarina Torulosa - Variant examples

[Rory]

I had a discussion with a council nurseryman the other month, and he was saying there is no difference between Casuarina Torulosa & Allocasuarina Torulosa. I disagree.
Now, I had purchased both different variants from the same nursery, and the nurseryman claimed that it would have been a mistaken print on the label, and that Casuarina Torulosa should be sold as Allocasuarina Torulosa. However!... here is proof.



So basically, in the pictures above, you can see the bark on a seedling of the Allocasuarina Torulosa is rough and corky, but the bark on the Casuarina Torulosa (above right pic) is smooth and bumpy. The foliage is very very similiar, but it does seem that the needles on the Casuarina are a teeny bit thicker than the Allocasuarina. Now, obviously some smartypants is going to say, 'but over time the bark will roughen up or cork up on the Casuarina Torulosa'. Not so. Take a look at these pics below of a much older bonsai of a Casuarina Torulosa, with the before and after shot, showing the close up of the trunk bark :



So, essentially, there are clearly 2 very different versions of the Torulosa, and I'll have to go back to that nursery and show him these 2 pics, because he said unless I had pics of what I mean, that he was not going to admit there was any difference. Even though I had actually bought the 10 inch pot version of a Casuarina Torulosa and the seedlings of the common 'corky rough bark' that the Allo Torulosa has, he says that the labels should be changed to all read Allocasuarina. I have often enquired at council nurseries and horticulturists in general, but no-one seems to have an opinion on the matter, and most just brush it off as saying they are the same species. Fortunately, now that I have managed to find seedlings of the same ages of both, it is a lot clearer to me in my opinion. I would love to hear from lovers of Casuarina or any interest in general.

Anyone, with any thoughts or interest on this?

[dansai]

I'll think you'll find that Allocasuarina is a relatively new genus that some casuarinas have been moved to including Allocasaurina torulosa by some botanist who has observed a difference geat enough to warrant the naming of a new genus. So Casuarina torulosa is now a synonym of Allocasuarina torulosa meaning they are in fact the same species. The differences in your plants may be due to incorrect labelling, age differences (seedlings of the same apparent size may in fact be different ages), individual genetics or environmental factors.

[Boics]

Quick look around online and I'd say Dansai might be correct here.

Are the two trees relatively the same age?

[Rory]

I'll think you'll find that Allocasuarina is a relatively new genus that some casuarinas have been moved to including Allocasaurina torulosa by some botanist who has observed a difference geat enough to warrant the naming of a new genus. So Casuarina torulosa is now a synonym of Allocasuarina torulosa meaning they are in fact the same species. The differences in your plants may be due to incorrect labelling, age differences (seedlings of the same apparent size may in fact be different ages), individual genetics or environmental factors.

I appreciate your comments, and I have to agree to disagree with you. I have now been to 3 nurseries where they stock Casuarina Torulosa in different aged stock, and they all exhibit the different bark to Allocasuarina Torulosa. The labels are not incorrect, and the different aged stock can be compared to the same corresponding stock of each type. Individual genetics, would mean literally individual, but every Casuarina Torulosa I have seen, does not have the rough bark. And the rough bark is evident on all Allocasuarinas. I have spoken to one helpful nurserywoman who advised that there is a possibility that this is the main difference, but she didn't have the rough variant available at her nursery to compare for herself and said it certainly appears to be a visible difference if this was the case.

[dansai]

From Wikipedia

Allocasuarina torulosa (rose she-oak or forest oak) is a tree which grows in sub-rainforest (just outside the main forest area) of Queensland and New South Wales, Australia. Originally described as Casuarina torulosa by William Aiton, it was moved to its current genus in 1982 by Australian botanist Lawrie Johnson.[1] It is the type species of the genus Allocasuarina.

[trident76]

Re dansai. Moot point. Full stop.

[Rory]

From Wikipedia

Allocasuarina torulosa (rose she-oak or forest oak) is a tree which grows in sub-rainforest (just outside the main forest area) of Queensland and New South Wales, Australia. Originally described as Casuarina torulosa by William Aiton, it was moved to its current genus in 1982 by Australian botanist Lawrie Johnson.[1] It is the type species of the genus Allocasuarina.

Thanks again for the comments,... but.... Firstly, the botanist who was at the state forest nursery I spoke to, said there is a difference between the 2, but the differences are minute. 'Minute' is the defining word here, and unfortunately Wikipedia can be written by anyone, and I can assure you, I would not take Wikipedia as fact. Having said that...the fact remains, that if you find a Casuarina Torulosa, it will not have the rough bark. Allocasuarina Torulosa will have the rough bark. Perhaps I didn't explain myself correctly. Nurseries can purchase the 2 different variants from wholesalers, and the bark on the ones labelled Casuarina are very different to the ones labelled Allocasuarina. So, unless you have actually seen the 2 variants, you can't really say that the point is made. The evidence is black and white, no matter what you read on the internet. I don't understand why anyone would think they are the same, considering they are obviously different.

[Boics]

Bbm.

I've noticed that nurserys and people in the industry can often be slow to take up "official" changes.

I'm not saying your right or wrong.
It is however possible that two different trees are being sub divided and sold incorrectly.

You have me intrigued....

[Drac0]

Strange one this - everything you find online suggests C. torulosa was moved to A. torulosa in 1982 and any search for either comes back to Allocasurina. So out with the books.......and it's a split decision.

From the number of books I have easily at hand, only 4 specifically mention either C. torulosa or A. torulosa directly - 3 books specifically on natives & one on plants in general. All the books were printed after 2000, but 2 of them were reprints of editions from the late 90's. And even with edition dates it was a down the middle split.

One natives book, (1996 edition) & the general plant guide both note the change of the Forest Sheoak (C. torulosa) to A. torulosa.

The other 2 books (1997 edition & 2004) both name C. torulosa directly with no reference to any changes. One only mentions the scientific name in relation to an image in the book, but the other gives the plant the common name "Rose She Oak" with fine weeping bronze-purple foliage, rusty gold flowers autumn-winter (I'll give you one guess what comes up if you search this online....).

Damn I'm so glad I was able to clear that for everyone....

One thing I did note, a search for Rose Sheoak on Daleys Fruit Trees site gets pic of a plant tag labelled as "Casuarina Torulosa", while seaching for A. torulosa or Forest Sheoak comes up with a (not in stock) plant listing. Funnily enough, both are said to have "thick corky bark". Maybe we should ask them if they know what's going on.....

I give up.....

Cheers

[dansai]

If you do a bit of reading, and I quoted wikipeadedia because it was the first thing to come up with a quotable sentence, you will find that in 1982 a botanist named Lawrie Johnson named a new genus Allocasuarina and moved some species of Casuarina to it. The differences between the 2, like your botanist said, are minute. Some of these changes are slow to be taken up by other botanists, and nurseries and the general public can be decades behind. A recent example is the moving of Callistemon species to Melaleuca. So botanically speaking they are identical.

Another more official (non wikipeadia) link is here

Distinguishing species can be quite difficult for species and true identification relies on flowers and often microscopic differences. Characteristics that are visible to the naked eye like bark and leaves can be varible within the genus. One character that is used for Casuarinas/Allocasuarinas is the leaves. These are not the 'needles' which are actually stems, but tiny leaves ringed around the junctions in the stem. If you have a powerful hand lens maybe pull a few stems and observe the leaves so as to determine if there are differences there.

[Rory]

Yeah I understand what you are saying dansai and I have been told the same thing as what you are quoting. It is a phenomenally interesting point, if you are a lover of casuarina, so I guess.... at the end of the day, if Torulosa is to be described as Allocasuarina and not Casuarina, then to quote romeo and juliet.... a rose by any other name would smell just as sweet.. ie...whether you call them Casuarina and/or Allocasuarina, .... Torulosa has 2 different types of bark variants that you can grow, which are both beautiful for their own reasons.

Personally, I prefer the look of the Casuarina Torulosa bark. I would be interested to hear if other people here have seen the 2 variations or have experimented with the stock that has the label 'casuarina torulosa', as you do not see them as often, because most people prefer the corky bark of the Allo. I guess, the part that is most interesting is for example, some nurseries grow the allo from seed, and others grow the cas from seed, and they are definitely different, so much so that they are overlooked by cas fans, as they instantly don't recognize them as torulosa because of the absence of the corked bark.

[Jason]

I just wish they'd stop moving the names, its hard enough already to remember! Thats right... I'm looking at you Lepto/Baekea/Babingtonia/Sannantha Most nurseries still label them as "Baekea" despite the name having changed twice since, so you can never really trust the label.

From what I've heard of she-oaks, a lot of the differences can only be seen under a microscope? Am still very new to them though, and trying to wrap my head around the differences

[GavinG]

They are technically the same species, renamed in 1982. The differences you are seeing are because the two different sources for the trees (one with the old label, one with the new) have different seed sources. There is a wide range of seedling variation in natives - if you have found a consistent difference between these two sources it's interesting, but the botanical facts are as dansai states. What you've been told may not be the full story.

Gsvin

[klaery]

Personally, I prefer the look of the Casuarina Torulosa bark.

You mean Allocasuarina torulosa don't you?

It has pretty much all been said but I'll add my bit:
In science/taxonomy you use the most up to date information. The species name is Allocasuarina torulosa and so that is the name that should be used. The fact that the supplier uses a name changed/abandoned in 1982 (over 30 years ago) is reason enough to be skeptical. If they are in fact the same species then they are Allocasuarina torulosa and what you are seeing is variation. Casuarina torulosa is what is known in nomenclature as a synonym (having been replaced by Allocasuarina torulosa), it no longer exists.

Also Wikipedia ain't all bad Just look at the references at the bottom. The Australian plant name index was referenced in text on the wikipedia page regarding the name change and when you follow the link you find all the relevant papers.

Edited: For clarity.

[cre8ivbonsai]