The New Zealand Plant Conservation Network

I was collecting some seeds from wild Ngaio this evening, I was surprised by the variation in purple color form one tree to the next. Is this normal? My mate told me that if the growing tips of Ngaio where not black this could be the Tasmanian Ngaio, Does anyone agree with that?

Fruit colour in Myoporum is variable and should never be taken as a guide to the species we have in New Zealand. Tasmanian Ngaio (Myoporum insulare) in the strict sense is not present in New Zealand, but we do have an entity allied to it which I traced back to Eastern Victoria, Australia (in the Victoria Flora it is treated as an unnamed species - on NZPCN website I call it M. aff. insulare). In New Zealand we seem to have a single clone of that, which is effectively female, so it rarely (if ever) sets seed in isolation. But if there is ngaio (M. laetum) nearby that will pollinate it, and then seed set is very heavy. Most (if not all) 'wild' seedling occurrences of "Tasmanian ngaio" that I have seen are really hybrid swarms (and these are fertile). So first answer DON'T collect ngaio seed from anywhere where you think Tasmanian ngaio is present. You will get hybrids and make the current situation worse by planting them out. Answer continued on next post below

Now Tasmanian ngaio in the strict sense has entire, glaucescent obovate to oblanceolate leaves - it looks very like Acacia sophorae. The so called "oil glands" are scarcely evident (if at alll) to the naked eye, the leaf tips are green to bright green and not very resinous. The New Zealand "Tasmanian ngaio" has lanceolate leaves which are serrated in the upper third to one quarter (sometimes upper half), it too is glaucescent, the "oil glands" can be seen with the naked eye - though not as prominent as in M. laetum - the stems are not tuberculate, and the young buds are dull green to bright green and scarcely resinous. In M. laetum the stems are tuberculate, the leaves are variable in shape and size and colour but always copiously spotted with "oil glands" that are easily seen with the naked eye, and the leaf buds are resinous and black to brown to green-brown. The flowers of both taxa are different in size and shape (I offer vegetative characters because flower may not be present)

Finally...rant...rant...hybrids being fertile will back cross with each other and their parents, producing heinous hybrid swarms - and these, as you'd expect, will express various permutations of either parent, so bud colour and degree of 'stickiness' is fairly hard to use reliably to distinguish hybrids, as is leaf shape, size and degree of serration, and flower size. I don't have space to explain this. So my suggestion is DON'T collect fruit of any ngaio unless you are 100% sure of what it is. If, as I think you live in Wellington, be very wary as lots of 'Tasmanian ngaio' was planted along State Highway One in the early 1970s and this has been a pollen donator to the local hybrid mess that Wellingtonian's now have. Same has happened here in Auckland, and its being made worse by nurseries 'eco-sourcing' "ngaio" seed from roadsides and those plants being used in restoration projects.
Hope that helps - it shard to explain in all the detail needed on the space allocation we have here

Great answer Peter, that's helped clarify the distinctions for me as well. There is quite a bit more here than on the species pages. On the M. aff. insulare page it says naturalised in 1978, I had thought it was much earlier but if that is the case does that mean that large trees in sites where it is unlikely to have been planted are most likely to be M. laetum? or is that a bit simplistic?

I did do M. aff. insulare but not all of that page so I will revise it. I am guessing though that the introduction date mentioned comes for Webb et al. (1988: Flora IV) which as I have said before is the date for which they accept a undisputed naturalisation not an introduction - and its not necessarily accurate either. Horticultural records infer that M. "insulare" came here in the 1950s (as M. serrulatum) but my research showed that Governor Grey got it from Ferdinand von Mueller in 1870 and planted it on Kawau Island - so its been here way longer than people believe - and it also means the hybridism has been going on for way longer. Also the fruit is bird dispersed - so we are now getting hybrids appearing km's away from planted sites - like what is happening right now in the Hauraki Gulf due to inappropriate plantings of "Tasmanian Ngaio" in places it should never have been put. So not "simple" at all.

Your third component (all good info. no rant involved!) hadn't come up when I put my spoke in, but Governor Grey! I had heard they were planted as some of the lighthouses got built, which is just educated hear-say, but if true that means nowhere is a safe option, back to getting positive ID's.
John, a propagation note: there are several seeds in a nut but from experience only one germinates at a time so a tray of seed will have several flushes. Ngaio also strike well from semi-hardwood tip cuttings if you are only after a specimen tree.

Hi Graeme - sadly plenty of Myoporum aff. insulare was planted in numerous places during the 1970-1980s in part because the former Lands & Survey Native plant Nursery grew it (thinking it was M. laetum) and so planted it widely on lands they administered or in sites they were contracted to plant. So it was planted in a number of reserves and parks - like along the Kaikoura coastline and yes I gather it was planted around some lighthouse sites, e.g, Tiritirimatangi Island, Mokohinau Islands etc (eradicated from these sites now). What's a worry is that his error is now being continued in some restoration plantings I have seen. For some parts of N.Z. it may now be too late. A decent study into this hybridism is needed.

Thanks Peter, guess what, I walked down the street past a Ngaio the day after reading your post. I always curse the council as they trash this tree with their weed eaters every time they come up the street...
No more, in fact its getting some roundup this weekend... take a look at the photo. To think I was all smug we didn't have them in Titahi Bay, only for one to be across the street!

Yes well...it happens...your image is to me a hybrid by the way (M. aff. insulare x M. laetum) - and demonstrates the problem of introgressive hybrid swarms as based on the oil glands and leaf dentition this one is closer to M. laetum than M. aff. insulare but the leaf buds suggest M. aff. insulare. When I was a lot younger than I am now (late 1960s to mid 1970s) I remember M. aff. insulare being planted all along the motorway between Porirua East and Tawa (Johnsonville), and around the streets of Titahi Bay.