Epiphytic ferns, like all ferns, reproduce with spores rather than seeds. Spores are single-celled reproductive units that have a range of terms associated with them:

• sporangium: a capsule that contains spores
• sporangia: a cluster of sporangium
• sori: clusters of sporangia on the frond surface

Sori can be used as an identification tool, check out these photos:

If you're interested in the mechanisms and details of spore dispersal, check out this natural history website. And because no spore blog would be complete without a fern life cycle, here is a nice diagram to express the details of this amazing process:

Spores are present on different species at different times of the year so its always worth keeping an eye out for these fascinating little features!

It is usually pretty easy to inspect the leaves of the plant you're looking at. Check all the stems you can find - if they are juvenile vines they will have lots of leaves - if they are more mature then the leaves will be fewer but you can often find some on the ground or on small shoots from the main vine. 

As the climbing rata mature, their vines thicken and can reach over 20 cm in diameter. Check out their bark for identity clues. I don't have bark photos for M. albiflora or M. carminea sorry.

The flowers of our climbing rata can be a real treat in the forest, they are either white or red:

No flower photos for M. albiflora or M. colensoi sorry, let me know if you've got some!

I hope that is useful... next time you're in the forest take some photos and post them here to build our collection!
A quick note: if you've received this blog via email please visit the website: nzepiphytenetwork.org to see the images, they don't work in the automatic email feed sorry.

Welcome to the 50th blog post for the New Zealand Epiphyte Network! Since beginning in April 2013 a small team of epiphyters have been regularly brightening your inbox with some pretty diverse discussions, stories, photos or ramblings. To celebrate, I’m going to reflect on some of this journey to date:

Epiphyte Island covered our mission to Rangitoto Island where we found 18 native epiphyte species growing the harsh volcanic rocks. This was both a favourite trip and a favourite story.

Investigating epiphytes of the Australian East Coast - by Jennifer is a story about awesome epiphytes and a new frontier of research over the ditch. Jennifer shared some sweet photos and made us all envious of her tree climbing expeditions!

The series on Facilitation Cascades is definitely a favourite. The facilitation cascade theory (and related ones) help to explain how each epiphyte species facilitates the arrival of the next one. There are four posts in this series so lots more to read if you're interested.

The recent discovery of The mind-blowing mimic vine is one of the most exciting news pieces to come from the canopy research scene lately. It was just last week so have a read about this species that can mimic a range of different host leaves.

Here are some of our favourite photos to date:

There is a great thought-provoking comment by Xerographica on The last uninvaded frontier and lots of great comments from Kirsty, Ang and Jennifer throughout. Thanks team!

Well the fascinating nature of this topic means that the interesting blogs will continue. The only thing that might change is a few different authors and hopefully a few more comments from our readers – let us know if you liked the post, what else you would like to know on the topic, or if you disagree with something we’ve said!

Here’s to the next 50!

All the best from the team at the NZ Epiphyte Network :)

Ernesto Gianoli and Fernando Carrasco-Urra from the University of Concepción in Chile have recently achieved the semi-impossible: they've become famous because of a botanical discovery!

The two researchers have published the first record of a plant that can imitate several hosts. Boquila trifoliolata is the only member of the Boquila genus and is a native vine of Chile and Argentina. It is common, vigorous climber with fluted, hairy stems. The most interesting feature of this plant is definitely its ability to grow leaves that match the shape and size of the nearest plant -  usually its host! 

The leaves of this vine are extraordinarily diverse. The biggest ones can be 10 times bigger than the smallest, and they can vary from very light to very dark. In around three-quarters of cases, they’re similar to the closest leaf from another tree, matching it in size, area, length of stalk, angle, and colour. Boquila’s leaves can even grow a spiny tip when, and only when, it climbs onto a shrub with spine-tipped leaves.

“There are some leaf features that are too hard to copy, such as serrated leaf margins,” says Gianoli. “It is common to see cases where Boquila “did her best”, and attained some resemblance, but did not really meet the goal.”

The same vine can even mimic several trees! If it crosses from one plant to another, its leaves change accordingly.

It is not yet clear why or how this species makes these changes. The authors have suggested that it may be avoiding herbivore predators and may utilise airborne chemicals or gene transfer to get the blueprint for the leaf features of their host plant. Its all a bit mind-blowing and exciting, whatever the mechanism. I wonder if there is anything in New Zealand doing this without us noticing?! 

One case of possible NZ plant mimicry has been noticed in matukuroimata (Alseuosmia pusilla), a fairly common forest shrub that appears to be mimicking the famous horopito, or pepper tree (Pseudowintera colorata). These plants are not at all related but often look very similar. It is thought that the matukuroimata is avoiding herbivore browsers my copying the threatening red tinges of the spicy horopito. Click here to read more.

A real kiwi bushman from Northland once showed us some Alseuosmia that were mimicking other shrub species including the long leaves of horoeka and mahoe. I don't have any photos sorry so I guess that one will have to remain a mystery until more investigations are done!

Some wording in this blog came from the excellent Ed Yong at National Geographic.

Sincere apologies for missing a blog last week! I was gallivanting in the South Island and missed my opportunity for computer and internet access. I hope the post for this week makes up for it :)

Myself and fellow epiphyter Olivia went mistletoe hunting during an epic journey from Otago to Waikato. Here are the results of our forays:

We arrived on the shores of Lake Ohau on a very crisp April afternoon with the goal of finding some beech mistletoes. This group of specialist stem parasites includes Peraxilla colensoi, Peraxilla tetrapetala and Alepis flavida, all of which have a strong preference for our five species of beech (Fuscospora and Lophozonia species).

Being North-Islanders (the majority of beech forest is in the South Island), neither of us were overly familiar with these mistletoes but were very excited to quickly discover an abundant population in open forest along the Lake Ohau shoreline. The problem was that we were under the impression that there were two or three species at this site so we spent hours trying to differentiate individual plants. It wasn't until Olivia found a distinctly different plant that we realised that all the plants we had been studying were actually all the same species: pikirangi (Peraxilla tetrapetala)! 

The second species we found was Alepis flavida which can be differentiated from Peraxilla tetrapetala by occasional pointed tips on the leaves and a lack of leaf galls. Both of these species are threatened and have declining populations.

Further west at the wonderful Ship Creek coastal forest remnant we stumbled across a few Ileostylus micranthus in fruit. They were growing on Coprosma shrubs and looked to be thriving in the west coast rain despite some insect browsing.

To top off our mistletoe hunting expedition we stopped on the western side of Lake Taupo where we had been told Tupeia antarctica could be found. We were not disappointed with a healthy population of plants on Pittosporum species. 

It was interesting to find a few dead individuals. They seemed to have got too heavy for the spindly branches they perched on and when their weight broke the branch they had lost their food supply. This species is threatened and has a declining population.