Tī kōuka – the cabbage tree – 8 April 2019
The last of the Otatara School classes (rooms 8&9) to visit the nursery this term arrived today in two groups. These classes are named after the easily recognisable tī kōuka or cabbage tree Cordyline australis. Each of the groups had time to share what they have learnt and noticed about the tī kōuka already and it was great to hear that these budding botanists and inquiring minds have found out lots about the cabbage tree. Then even though this tree is easily recognisable, when you only have the leaves in front of you identification can still trick even the most astute! We looked at the leaves of other school class plants and then headed out around the tracks to see what ones we could notice. Around the restored pond area many tī kōuka were found, while in the mature kahikatea forest none were found, proving what this class had learnt about tī kōuka not liking shady places to grow. This got us into noticing the differences in what was growing in these two areas. We talked about growing a forest, by planting out colonising or nursery species to provide the shelter needed for mature forest tree species to be able to then grow. As we walked we noticed the different seeds - of kahikatea, tī kōuka, mānuka, harakeke, and mingimingi - some which were in pods, some inside the fruit, and some seeds on the outside. We also looked at the two species of horoeka/ lancewood and the heteroblastic nature of this tree. We went back to the education centre and set about answering how many seeds there are on a tī kōuka tree. A huge fruiting head had been collected and each small group set about stripping the fruit off the branches (which is a job we do at the nursery at seed collecting time), and counting the fruit. The number of seeds inside each fruit ranged from 3-11, there was also a range of number of fruit on each stalk, and there were a number of stalks on the fruit head. We also noticed that different sized tī kōuka have a different number of fruit heads. We look forward to getting the answers to this mathematical problem! This class also heard about the importance of Otatara and Sandy Point for tī kōuka, the cabbage tree moth that lives on tī kōuka, and we wondered where the biggest cabbage tree would be in Otatara? This class sat at the seat on the new track and looked towards the layers of forest. “It looks like a painting” someone said….it sure does!
Bronwyn and Chris
Posted: 9 April 2019