| I wanted to make sure you got a good answer to your question so I shot off a quick note to Dr. Wilbert Hetterscheid who is the world's leading botanist in the field of Amorphophallus species. This is Wilbert's response: "The tuber is indeed the (strongly condensed, undergound) stem, consisting in most species of only one node, being renewed very year (few exceptions exist). The leaf is developing from the stem. I wouldn't call the leafstalk a "trunk" because that indicates something like the "stem of a tree. It is a leaf stalk and that is the best indication (botanists call it a petiole). The rest of the leaf is the blade or "lamina" cut up in several"leaflets" but none of these latter are real leaves, they just imitate it as part of a full scale tree-imitation. In many species (most) only one leaf develops per season (except often in seedlings which stay in growth a bit longer and develop more leaves). Some species produce more than one leaf when mature (paeoniifolius does often, few do it always and a few are semi-evergreen). Drooping leaf margins might be dormancy setting in but may equaly be a sign of a tuber not being healthy, maybe losing roots. The normal procedure of starting dormancy is a furrow developing along the leaf stalk and yellowing of the leaflets. Drooping is the next and then the leaf stalk suddenly collapses." You were doing a great job of describing your plant but I saw one error I thought you'd like to understand better. The plant has one single leaf thus only one petiole rather than five. The petiole is the portion of the leaf that is the support for that blade. I failed to ask Wilbert if the 5 leaflet supports you were trying to describe as "petioles" are truly midribs but I suspect that would have been his response. Most people try to call the leaf support a "stem" but the stem is the central axis of the plant which produces nodes. Nodes produce roots and petioles. The petioles are part of a leaf and are the "stalks" that support the leaf. In the case of this genus the stem is underground and is known as the tuber. Great question and I hope this helps. |