juvenile vs. adult

From: Alektra at aol.com on 2002.11.25 at 05:11:15(9639) Thanks, everybody, for explaining about Epipremnum aureus (what I was calling common pothos). Now about this "adult form" versus "juvenile form" thing... I've also heard about this change in looks for common green vining philodendrum (whatever THAT is really called). And I think I've actually seen something like this sort of change in a very unrelated houseplant, the thing sold as "aloe vera," so maybe this is not an uncommon process across the vegetative world? Of course "aloe vera" doesn't climb, but the change in appearance is very striking. Let me review the process for aroids as I understand it, what we see growing in the florist's little pot is a juvenile form that looks very little like the adult. I sense from cryptic discussions I've read elsewhere that the switch to an adult form requires at least a tall moist standard for the vine to cling to and climb, plus copious amounts of sunlight. Please correct me on the above. Then, my questions (sorry they're so basic but I would guess there may be someone else on this list who doesn't know this stuff), for anybody to answer: 1) Does this happen only to vining aroids? 2) Besides lots of light, does this also require lots of heat and numidity? 3) So can this be done indoors under home conditions without a greenhouse? Can this be done in a greenhouse? Is this strictly for outdoors in tropical climates? +More 4) What actually are the basic trigger and mechanism of this change? 5) What is the advantage of this change in evolutionary terms? 6) Is there a particular book that everybody else learned all this from already? Thanks, and sorry if this seems like I'm quizzing you. I'm just kind of stunned at the revelation that feral pothos can grow that big.

From: "Plantsman" plantsman at prodigy.net> on 2002.11.25 at 16:48:08(9641) Seems like I remember the common heart-leafed philodendron vine is/was named Philodendron oxycardium. I've seen older Aloe vera that were almost unrecognizable from the juvenile form: the color was much deeper and the wide leaf margins were quite "spikey". +More I've seen the common Epipremnum aureus changing from the juvenile leaf shape and size even in three foot tall specimens found at our area Home Depot. They were already getting quite rectangular with some perforations of the leaves and were quite happily covering the tree fern poles. We've got a E. aureus in my office that's been here over twelve years and due to the low light and low humidity, it's never left the juvenile stage. It's over ten feet long, still with small heart-shaped leaves, mostly green. I suspect heat, light and humidity would kick it off into mature form. David Sizemore Kingsport, TN (Zone 6A) ----- Original Message ----- To: Sent: Monday, November 25, 2002 12:11 AM Subject: [aroid-l] juvenile vs. adult : Thanks, everybody, for explaining about Epipremnum aureus (what I was : calling common pothos). Now about this "adult form" versus "juvenile form" : thing... I've also heard about this change in looks for common green vining : philodendrum (whatever THAT is really called). : : And I think I've actually seen something like this sort of change in a very : unrelated houseplant, the thing sold as "aloe vera," so maybe this is not an : uncommon process across the vegetative world? Of course "aloe vera" doesn't : climb, but the change in appearance is very striking. : : Let me review the process for aroids as I understand it, what we see growing : in the florist's little pot is a juvenile form that looks very little like : the adult. I sense from cryptic discussions I've read elsewhere that the : switch to an adult form requires at least a tall moist standard for the vine : to cling to and climb, plus copious amounts of sunlight. : : Please correct me on the above. Then, my questions (sorry they're so basic : but I would guess there may be someone else on this list who doesn't know : this stuff), for anybody to answer: : : 1) Does this happen only to vining aroids? : 2) Besides lots of light, does this also require lots of heat and numidity? : 3) So can this be done indoors under home conditions without a greenhouse? : Can this be done in a greenhouse? Is this strictly for outdoors in tropical : climates? : 4) What actually are the basic trigger and mechanism of this change? : 5) What is the advantage of this change in evolutionary terms? : 6) Is there a particular book that everybody else learned all this from : already? : : Thanks, and sorry if this seems like I'm quizzing you. I'm just kind of : stunned at the revelation that feral pothos can grow that big.

From: "Harry Witmore" harrywitmore at witmore.net> on 2002.11.25 at 17:18:02(9642) This is really common among aroids. I have a Philodendron scandens that is climbing the side of my greenhouse and the leaves are beginning to get progressively larger. The leaves now are about 8 inches across. It's also happening to a Syngonium in the same greenhouse. But' I also have a Monstera deliciosa that is running across the ground in my greenhouse and the leaf is about 2 feet across. It was an escapee from a pot. The parent pot leaves are about 1 foot across. It's also happening to ivy in my front yard. When it reaches the tops of the trees, the leaves are considerably larger in size than it is on the ground. I can happen in a relatively small space but I think the key is how high it can get and how much light. Harry Witmore +More Cloud Jungle Art www.witmore.net -----Original Message----- [mailto:aroid-l-owner@lists.ncsu.edu]On Behalf Of Alektra@aol.com Sent: Monday, November 25, 2002 12:11 AM To: aroid-l@lists.ncsu.edu Subject: [aroid-l] juvenile vs. adult Thanks, everybody, for explaining about Epipremnum aureus (what I was calling common pothos). Now about this "adult form" versus "juvenile form" thing... I've also heard about this change in looks for common green vining philodendrum (whatever THAT is really called). And I think I've actually seen something like this sort of change in a very unrelated houseplant, the thing sold as "aloe vera," so maybe this is not an uncommon process across the vegetative world? Of course "aloe vera" doesn't climb, but the change in appearance is very striking. Let me review the process for aroids as I understand it, what we see growing in the florist's little pot is a juvenile form that looks very little like the adult. I sense from cryptic discussions I've read elsewhere that the switch to an adult form requires at least a tall moist standard for the vine to cling to and climb, plus copious amounts of sunlight. Please correct me on the above. Then, my questions (sorry they're so basic but I would guess there may be someone else on this list who doesn't know this stuff), for anybody to answer: 1) Does this happen only to vining aroids? 2) Besides lots of light, does this also require lots of heat and numidity? 3) So can this be done indoors under home conditions without a greenhouse? Can this be done in a greenhouse? Is this strictly for outdoors in tropical climates? 4) What actually are the basic trigger and mechanism of this change? 5) What is the advantage of this change in evolutionary terms? 6) Is there a particular book that everybody else learned all this from already? Thanks, and sorry if this seems like I'm quizzing you. I'm just kind of stunned at the revelation that feral pothos can grow that big.

From: MossyTrail at cs.com on 2002.11.25 at 19:23:26(9643) In a message dated 11/25/2002 8:23:11 AM Pacific Standard Time, Alektra@aol.com writes: > 1) Does this happen only to vining aroids? +More No. The Marcgraviaceae do it, too: the juvenile form is has leaves nearly flat against the tree (adnate), the adult stage arches out from the tree trunk and has different leaves. I have even seen one specimen of Marcgravia brownei, the main shoot juvenile, with a side shoot whose beginning was the adult form, but after only a few centimeters reverted to juvenile and began climbing again right beside the original shoot. > 2) Besides lots of light, does this also require lots of heat and humidity? I don't know for sure, but probably the closer you can come to the plant's natural habitat, the better. The above-mentioned Marcgravia was at Montverde, Costa Rica -- a high-altitude site classified as "temperate," that is, seldom getting hot (I often found it rather chilly!), but no frost, either. The lack of frost allowed typically tropical taxa to grow despite the cool temps. Monteverde is a mist-shrouded "cloud forest," but because of its tropical latitude, an overcast day there was still brighter than an overcast day up north. > 3) So can this be done indoors under home conditions without a greenhouse? > Can this be done in a greenhouse? Is this strictly for outdoors in tropical > climates? Maybe our esteemed Professor Croat can answer this. If any greenhouse can create the right conditions, his wall can! > 4) What actually are the basic trigger and mechanism of this change? > 5) What is the advantage of this change in evolutionary terms? Hmm...I don't have my _The Genera of Araceae_ handy, but the chapters on Aroid biology may help with this answer. > 6) Is there a particular book that everybody else learned all this from > already? > No one single book. I read as much as I can about tropical nature, and so probably cannot state any specific book for anything I have learned, unless I especially go look it up. Jason Hernandez Naturalist-at-Large

From: "Julius Boos" ju-bo at msn.com> on 2002.11.26 at 10:24:40(9645) Hello Again, I suggest that you purchase Deni Bown`s book 'Aroids', most major bookstores carry it. +More Most climbing Aroids in MANY genera have juvenile forms that are unrecognizable as being even related to the adult form, different shaped leaves, size, shape and 'splits/divisions', etc.Some of the common ones sold here in the USA would be species of Monstera, Philodendron, Syngonium and the one under discussion. You are correct that many plants are very different in appearance when young vs. adult. I will continue my explanations in-between your questions (below). >>Thanks, everybody, for explaining about Epipremnum aureus (what I was calling common pothos). Now about this "adult form" versus "juvenile form" thing... I've also heard about this change in looks for common green vining philodendrum (whatever THAT is really called). And I think I've actually seen something like this sort of change in a very unrelated houseplant, the thing sold as "aloe vera," so maybe this is not an uncommon process across the vegetative world? Of course "aloe vera" doesn't climb, but the change in appearance is very striking. Let me review the process for aroids as I understand it, what we see growing in the florist's little pot is a juvenile form that looks very little like the adult. I sense from cryptic discussions I've read elsewhere that the switch to an adult form requires at least a tall moist standard for the vine to cling to and climb, plus copious amounts of sunlight.<< Correct---I do not believe that except for a very few of the naturally smaller species that growing indoors would work if you want to produce an adult-sized specimen of any of these. >>Please correct me on the above. Then, my questions (sorry they're so basic but I would guess there may be someone else on this list who doesn't know this stuff), for anybody to answer: 1) Does this happen only to vining aroids?<< No. Other Aroids, even the low-growing terrestrial ones have both 'forms', I have small Dracontioides that at this size have leaves with no 'holes', and in a short while and when larger will produce larger leaves with many holes all over the leaf blades. There are many more examples in the Aroid world. 2) Besides lots of light, does this also require lots of heat and humidity?< Yes. Monstera can grow in a 'drier' atmosphere, and that it why some sps. make 'good' house plants. 3) So can this be done indoors under home conditions without a greenhouse?< Not really, they will or may survive, but not 'happily'. >>Can this be done in a greenhouse? Is this strictly for outdoors in tropical climates?<< Yes---a BIG greenhouse!! 4) What actually are the basic trigger and mechanism of this change?< When the plant encounters a suitable and tall-enough support, be it a tree of rock cliff, etc it grows and 'changes' to its adult form. The actual 'trigger' for change from the adult form and also from seedling to adult is a most fascinating thing to me, it is reported that the seedlings that may germinate on open ground and the thin runners put out by adult plants on overcrowded trees or other supports do NOT grow toward the light as in most plants, but seem attracted to dark areas/shadows which may indicate the presence of a new large tree or rock-face!! 5) What is the advantage of this change in evolutionary terms?< A guess---the 'drive' to reproduce, and to do this the plant MUST reach adult size, and to reach adult size MUST find a suitably large 'support'. 6) Is there a particular book that everybody else learned all this from already?<< Not all, but MOST can be learned from THE best book on Aroids available 'out there', Aroids, by Deni Bown. Thanks, and sorry if this seems like I'm quizzing you. I'm just kind of stunned at the revelation that feral pothos can grow that big.< It is such a pleasure replying to a beginner like yourself, and my hope is that many others like you who may read this may become as enthused as I have been and still am after all these years at these wonderful and mysterious plants! GOOD GROWING!!! Julius Boos WPB, Florida.

From: "Eduardo Goncalves" edggon at hotmail.com> on 2002.11.26 at 12:17:55(9646) Dear fellow (I coudn't find your name in the message), Here follows my contributions to your question. Probably you will get much more then this. 1) Does this happen only to vining aroids? Nope. Noticeable changes in leaf form also occurs in terrestrial tuberous plants. Leaves in Taccarum warmingii are triangular hastate when young, then it has pinatelly compound leaves. Spathantheum usually have a cordate leaf when young, that are usually deeply incised in mature plants. Sometimes, adult plants can even keep cordate leaves. However, I think that most of the incredible changes occurs in vining aroids, like shingle plants (Monstera). 2) Besides lots of light, does this also require lots of heat and numidity? I can see no direct relationship, but if you have more heat and humidity, you plant will grow faster! In my experience, if you give a good support for the growing plants (i.e., a totem or a nice tree), it will change from a juvenile plant to an adult plant, whatever the time it takes. I really think that the presence of a stem attached to the substrate is more important than the light. Climbing plants growing with full sun, but no totem, usually will not yield adult stems. 3) So can this be done indoors under home conditions without a greenhouse? Yes, if you have enough light and a proper totem to climb. Room enough as well! +More Can this be done in a greenhouse? Is this strictly for outdoors in >tropical climates? It CAN be done in a greenhouse, but it is not easy, because some time it needs a lot of growing space. BGs like Kew or Missouri have an interesting apparatus for make climbers grow freely in their scientific collection, but it is not easy and some plants will need usually much more than we can give in a greenhouse. 4) What actually are the basic trigger and mechanism of this change? Nobody knows exactly. "We" are suspicious that the diameter of the stem is the trigger for the changes in leaf shape (as well for triggering the flowering proccess), but we do not know the trigger for change in diameter. I think that the presence of "excited roots", i.e., roots that were in contact with a substrate and were able to embrace it have a positive effect on the rise of diameter. "Non-excited roots" usually shrinks and probably "say" something to the stem concerning "ok, we do not have a totem, so you better keep slender, long and look for a decent substrate to climb". 5) What is the advantage of this change in evolutionary terms? There is a real environmental change from the forest ground (where most climbers germinate) to the high canopy. If a plant is able of using better each level That would be a paramount to success in this habitat. 6) Is there a particular book that everybody else learned all this from already? I would love to know. If you find it, let me know! Very best wishes! Eduardo. _________________________________________________________________ MSN 8 helps eliminate e-mail viruses. Get 2 months FREE*. http://join.msn.com/?pageþatures/virus

From: "Julius Boos" ju-bo at msn.com> on 2002.11.28 at 18:43:48(9662) Hello Deni! Good to hear your 'voice'. Just a point, but I had quite a conversation w/ Peter Boyce some time ago about the correct name for the 'common pothos' which you report to be Epipremium aureum. Peter explained the this vari. plant had been REFERED to the species E. aureum, as the cultivated plant resembled the herb. specimens of wild-collected E. aureum, but that he had never felt totally 'comfortable' with that determination. He went on to say that he was pretty excited as he believed that he had just found the TRUE source of the cultivated plant, some remote Island in Indonesia I believe. This wild plant was a GOOD match for the cultivated plant, was NOT E. aurium, and he intended to describe it as a new species. Hope that things go well for you! STILL enjoying my copy of 'Aroids'! Best Wishes, Julius Boos. +More >>By chance, in connection with some updating of a garden plant encyclopedia I'm currently working on, I have had some recent communications over the correct name for the heart-leafed philodendron. According to Tom Croat, it's Philodendron hederaceum. All other names (P. cordatum, P. oxycardium, P. scandens) are synonyms. The reference for this is: Croat, T. 1997. A Revision of Philodendron subgenus Philodendron (Araceae) for Mexico and Central America. Ann. Missouri Bot. Gard. 84: 314-704. Also, the correct name for common pothos is Epipremnum aureum. On the subject of juvenile and adult leaf shapes, may I recommend Michael Madison's Revision of Monstera - interesting explanations and diagrams. I thought this was once published in Aroideana but maybe I'm wrong. Deni Bown -----Original Message----- [mailto:aroid-l-owner@lists.ncsu.edu]On Behalf Of Plantsman Sent: 25 November 2002 16:48 To: aroid-l@lists.ncsu.edu Subject: Re: [aroid-l] juvenile vs. adult Seems like I remember the common heart-leafed philodendron vine is/was named Philodendron oxycardium. I've seen older Aloe vera that were almost unrecognizable from the juvenile form: the color was much deeper and the wide leaf margins were quite "spikey". I've seen the common Epipremnum aureus changing from the juvenile leaf shape and size even in three foot tall specimens found at our area Home Depot. They were already getting quite rectangular with some perforations of the leaves and were quite happily covering the tree fern poles. We've got a E. aureus in my office that's been here over twelve years and due to the low light and low humidity, it's never left the juvenile stage. It's over ten feet long, still with small heart-shaped leaves, mostly green. I suspect heat, light and humidity would kick it off into mature form. David Sizemore Kingsport, TN (Zone 6A) ----- Original Message ----- To: Sent: Monday, November 25, 2002 12:11 AM Subject: [aroid-l] juvenile vs. adult : Thanks, everybody, for explaining about Epipremnum aureus (what I was : calling common pothos). Now about this "adult form" versus "juvenile form" : thing... I've also heard about this change in looks for common green vining : philodendrum (whatever THAT is really called). : : And I think I've actually seen something like this sort of change in a very : unrelated houseplant, the thing sold as "aloe vera," so maybe this is not an : uncommon process across the vegetative world? Of course "aloe vera" doesn't : climb, but the change in appearance is very striking. : : Let me review the process for aroids as I understand it, what we see growing : in the florist's little pot is a juvenile form that looks very little like : the adult. I sense from cryptic discussions I've read elsewhere that the : switch to an adult form requires at least a tall moist standard for the vine : to cling to and climb, plus copious amounts of sunlight. : : Please correct me on the above. Then, my questions (sorry they're so basic : but I would guess there may be someone else on this list who doesn't know : this stuff), for anybody to answer: : : 1) Does this happen only to vining aroids? : 2) Besides lots of light, does this also require lots of heat and numidity? : 3) So can this be done indoors under home conditions without a greenhouse? : Can this be done in a greenhouse? Is this strictly for outdoors in tropical : climates? : 4) What actually are the basic trigger and mechanism of this change? : 5) What is the advantage of this change in evolutionary terms? : 6) Is there a particular book that everybody else learned all this from : already? : : Thanks, and sorry if this seems like I'm quizzing you. I'm just kind of : stunned at the revelation that feral pothos can grow that big.

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