Mauritius Botanical Gardens Bamboo stumps

I’m after a link to an explanation of why a cold card node is important. Could someone please head me in the right direction

I walked up the beautiful Piètre Both Peak in Mauritius yesterday. Hauled my old bootie up some seriously steep rope climbs. Yes, terrified of heights but did it anyway

GM what a beautiful place I find myself in. Travelling in Hvar, Croatia. Just wow