The possibility of creating a tropical maple is there but the probability is very slim or even unlikely.The subject is centered on this unanswered probe " Is the behavior of a decidous tree controlled by its genectic make-up or is it a response to the changing seasons?" If the former is correct then the quest of a tropical maple is utterly hopeless. However I am somewhat convinced that it is the autumn season that enforces trees to shed leaves; hence I believe I have a fair chance to acclimatize maples to the tropics. I have subjected first year maple seedlings to a tropical enviroment created indoors in a closed chamber under artificial lights. Despite the avoidance of chill, most seedlings still go into hibination/domant state around October/November. However a few of the Palmatum seedlings, especially those that show excellent growth patterns, continue to grow new terminal shoots even as late first week of October . Below is a photo of such a seedling taken yesterday (approachig winter already). The green leaf portion of the plant represents the summer growth whereas the moroon portion grew in early October. There is no apparent signs of the plant going domant and I have a few of her siblings still sprouting new shoots right into mid-November. You will observe that this seedling has accelerated growth as the ruler is 16 inches long. If this plant does not suffer too adversely for the lack of domancy, then I cannot see why it cannot be tropicalized within a span of 4 years. This unexpected growth comes as a surprise as in the other forum most readers laugh and some even ridicule me for trying to experiment. Let's us see who has the last laugh?
You can't create a tropical maple. You can, perhaps, grow a maple species native to a temperate area in tropicalesque conditions - at least for a time. The answer to the "unanswered probe" is available in Gan, S. and R. M. Amasino (1997) Making sense of senescence: molecular genetic regulation and manipulation of leaf senescence. Plant Physiology 113: 313-319 (Link to PDF):
There are tender, warm temperate/subtropical maple species already. These have simple, evergreen leaves. Sec. Palmata also includes tenderish Acer campbellii, like a Japanese maple but less elegant in habit and less hardy. Birch and katsura tree seeds planted in fall and grown indoors under lights can be kept going right through until the following spring.
Thank you for the link to leaf senescence, which has given me lots of pleasurable reading.This phenominum applies to both temperate and tropical plants, though the triggering process may be different. Looking at it from a layman's simpler level, leaf senescence commences when the photosynthesis rate in a leaf falls below the level which makes it a contributor of food nutrition to the plant. However my unanswered probe refers to the domancy of deciduous plants or to put it in another context "Can deciduous plant thrive on without dormancy?". We are all aware of the requirement of dormancy as a condition for growth vigor in Spring. But this fact does not preclude that some deciduous plants may survive without undergoing dormancy, my formula for a tropical maple. Nobody can create a blue rose, but this fact does not stop scientists and hybridisers from trying. Hurrah for the human spirit.
Ah, ok. Well, there are answers to that question as well. Here's an abbreviated answer from Dr. Joseph Armstrong: Re: a deciduous tree in a controlled environment (original question) Dr. Rolf Borchert is an plant ecophysiologist at the University of Kansas. He provides a number of his papers online which I think comprehensively addresses the question: The Phenology of Tropical Trees and its Environmental Control. In particular, check out: Borchert R, Robertson K, Schwartz MD, Williams-Linera G (2005) Phenology of temperate trees in tropical climates. Int. journ. Biometeorol. A recent book from the International Society for Horticultural Science on the subject as it pertains to fruit trees: Dormancy and the related Problems of Deciduous Fruit Trees Lastly, another bit of assumed evidence (i.e., I have no references, but I think it might be fair to state...) on the general lack of success from a historical perspective. Considering that European explorers and colonizers visiting tropical areas seemed to take a bunch of domesticated animals with them, is it possible they also took plants that were familiar to them? I'd say very likely, both as food and medicine. I don't know of any success stories three- or four hundred years later about these presumed temperate introductions into tropical areas.
Daniel Thank you for the abundance of reference materials, of which papers by Dr Rolf Borchert prove very relevant. Quote:From "Borchert R, Robertson K, Schwartz MD, Williams-Linera G (2005) Phenology of temperate trees in tropical climates. Int. journ. Biometeorol. In Press" (1)Implicitly, within temperate species ranging from cold-temperate to tropical climates (Table 1) there should be eco-physiological races (ecotypes) that differ with respect to cold-hardiness, bud dormancy and response to day length. Such genetic differences were observed in a provenance test with Acer rubrum, in which seedlings of provenances from southern Florida to northern New York were grown outdoors in Gainesville, Florida (TJan=6◦C), located just north of Florida’s citrus growing area (Fig. 1; Perry and Wang 1960). Predictably, bud break in nonchilled, field-grown seedlings of northern provenances was several weeks later than in seedlings chilled in a cold-room for 1 month (Fig. 7, circles vs squares). Under the same temperature regime, bud break of seedlings from southern Florida (TJan=13◦C) was in mid-January, 5 weeks earlier than in local seedlings and 12–14 weeks before bud break of all chilled northern-provenance seedlings in mid- to late April (Fig. 7, diamonds vs squares). January temperatures in Gainesville were thus permissive for bud break of southern ecotypes, but not sufficient to cause bud break of the chilled northern ecotypes, which, like the species discussed above (Fig. 3C), probably require induction of bud break by increasing day length. In northern ecotypes of A. rubrum, and probably in other species adapted to cold-temperate climates, damage to young, frost-sensitive shoots by late frosts is apparently prevented by the combined requirements for chilling and increasing day length, which are lacking in southern ecotypes and in temperate trees growing in Buenos Aires, Argentina. (2)Temperature-dependent phenology of temperate broadleaved trees and tropical tree phenology have been studied mainly in northern climates with a cold winter and in the seasonally dry tropics, respectively. Little is known about the transition from temperate to tropical phenology and the geographical boundaries between these major phenological patterns. In contrast to Europe, where the range of most broad-leaved tree species ends abruptly in the Mediterranean climate south of the Alps, in North America broad-leaved forests with a moist summer growing season range from 45◦N in northern USA to the tropical montane forests of Mexico and Central America at 15–20◦N (Fig. 1). Correspondingly, a number of temperate tree species or genera range from northern USA and Canada to Central America, Mexico or southern Florida (Fig. 1; Marquis 1990). In their northern range species such as Acer rubrum (Walters and Yawney 1990), Fagus grandifolia (Tubbs and Houston 1990) and Carpinus caroliniana may be deciduous for ∼6 months, but in the southern, tropical part of their range they exchange old for new leaves within a few weeks in January–February (Peters 1995; Tomlinson 1980; Williams-Linera 1997; Williams-Linera et al. 2000), i.e., their phenology is similar to that of tropical leaf-exchanging species (Borchert et al. 2002; Borchert 2004). Along the N-S gradient of increasing temperature the transition from a temperature-driven, deciduous phenology to a tropical, nearly evergreen phenology thus occurs within the same, wide-ranging temperate species. From the above two quotations, it is evident that the temperate decidous species had undergone drastic phenotypic changes on their migration along the NS gradient from 45 deg N to 15-20 deg N. Reference: Quote: "Along the N-S gradient of increasing temperature the transition from a temperature-driven, deciduous phenology to a tropical, nearly evergreen phenology thus occurs within the same, wide-ranging temperate species." Thus what I am atempting to do is extend this NS gradient to reach the equator, where the climate is tropical rather than subtropical. Another interesting point can be deduced from Borchert's papers. Adaption to climatic changes has caused the time of bud breaks of the same specie to become different along the NS gradient. This phenominum of bud break timing has been inherited into the seeds as seedlings from different regions of the NS gradient perform the bud breaks similar to their mother trees even when these seedlings were germinated in one geographical location. Thus adaptations due to climate are imprinted into the genetic make-up of the seed and is contrary to what had been claimed by most readers in this and the other forums.
In one of my replies I had stated that I had seen a number of temperate deciduous species growing in the tropics. Well I shall be making a brief visit to the South East Asia and shall be vigilent in looking out for these species, which had adapted to be tropical evergreen. When successful I shall provide pics for this forum, hopefully.
False statement - no conclusions were made about the expansion of distribution ranges ("migration") in this paper. Looking at broad groups (i.e., genera or families) over evolutionary time (i.e., in the scope of millions of years), the pattern for expansion of distribution ranges is from the tropic climates to temperate climates. The referred quote is specifically about species of plants that have an existing range from cold-temperate to tropical climates. Unless you are working with these species in situ, you are not attempting to extend the range. From my understanding, you are attempting to cultivate some individuals of a species in tropicalesque conditions. I'm not sure where the contrarian claims were made, but I'll reassert the statement made in Gan and Amasino: "Like many other developmental processes, it is a genetically controlled program regulated by a variety of environmental and autonomous factors."
. Interesting conclusion you have arrived at by infering the requirement of working with species in situ. Let's us then examine the maple specie "Acer rubrum" referred to by Dr. Borchert. He has not claimed that the specie has migrated from the tropical climate to temperate; but he did claim that A. rubrum is a temperate specie. This would preclude the move from the tropics to temperate regions, otherwise he would have refered to A. rubrum as a tropical specie. What I suspect could be the possible scenerio is the Acer rubrum had its origin somewhere inside the NS gradient, possibly midway if migration remains at the same rate as it moves northwards and southwards. It is more likely that the point of origin is more North of this midway than South as growth in the warm climates is more robust than in temperate and migration rate tends to speed up. It is true that I am not working with Acer rubrum in situ with reference to Dr Borchert's study, however controlling the climate of the environment to imitate the 'in situ' location dispenses the need to grow the plant in a particular geographical location (in situ). To say the migration of Acer rubum is an evoluntionary process is as questionable as to say that human intervention has played a hand in this migration.
For what it's worth, I did have a look at the origin of Acer. From: Pfosser M, Guzy-wróbelska J, Sun BY, Stuessy T, Sugawara T, et al. (2002) The Origin of Species of Acer (Sapindaceae) Endemic to Ullung Island, Korea. Systematic Botany: Vol. 27, No. 2 pp. 351–367 Looking at the [WIKI]Geologic Time Scale[/WIKI], this would have been a time when Alaska had subtropical conditions, though it did immediately precede a general cooling of this expanded global tropical climatic phenomenon. I also checked "where in the world" Alaska was at 55mybp, shown in this movie from Berkeley - not too much different from today.
Daniel Thank you for the tremendous amount of efforts you must have expended to come up with the sites. Though I suggested that a fossil study could perhaps unlock the secrets of the origin of Acer, I never could have imagined that the topic had already been researched. Also I had not imagined the complexity of the task of fossil tracking to pin-point the problem I had presented. I can only have the highest regard for the inter-connectivity of academicians, whose combined resources would far outstrip whatever a layperson like me could muster up. For this help I am greatly indebted.
Barry Tomlinson compared temperate to tropical trees in "The biology of trees native to Tropical Florida," available from Fairchild Tropical Botanic Garden. In Florida, temperate trees drop out from north to south. Interestingly, the local version of the sugar maple has a range extending to just south of Orlando. The Leu Gardens in Orlando have tried out a lot of east Asian trees and shrubs, including maples. Regrettably, Japanese maples just won't make it in most of Florida.
Let's use this document as a starting point. I see from the Figure 2. (Shaded area represents potential planting range.) graphic that I have my Maples in one of the white areas. Let's also be fair that the information in this file is just a little outdated. Acer palmatum - Japanese Maple For several years periodicals as well as articles and published information, even people in this forum, have stated that certain areas cannot grow Japanese Maples without supplying much to anything as a basis for the reasoning as to why that may be true for the areas depicted in white, the "other than the shaded areas" in the graphic. Yes, growing Japanese Maples in some of those areas can be rather difficult but they can be grown in several of the non-shaded areas. I've had a collection of over 200 Japanese Maples planted in a variety of home gardens and one estate garden for many years. My first Japanese Maple was purchased back in 1968 and it still is alive and well in an estate garden about 60 miles down the road from me. By the way, all of the Maples I have or have given to friends and relatives for their yards are all in the white areas in the graphic. For many years it was thought that no one could successfully grow a Japanese Maple in the Central Valley until in the mid 60's a collection of 300 named forms was seen by a group of people that all deemed it impossible for a Japanese Maple to live and thrive and not burn up in the greater Fresno area during our Summer heat. That set the stage for other areas to also want to grow Japanese Maples in regions of the US that did not have any to speak of and the Southern part of the US was one of them. So much so, many nurseryman and several arboretums and botanical gardens as well as Universities allover the South got many of their original Maples from that same nursery. While I am on a hot streak, let me go back to the original post. There have been Japanese Maples that have not shed their leaves grown both in a container and in ground in a greenhouse for three years and slightly longer before the plants just shut down and died. If we know the hours amount of light that a Japanese Maple requires and the amount of heat the plant needs to be constant we can do it but there is a catch. If we truly want to have these plants keep their leaves on the plant for three years and longer, we have to supplement a lot of nutrients along the way to pull it off. There comes a time when we burn the plant out by giving it too much nutrients just to sustain growth as it is the growth sustaining part that is the most difficult aspect to overcome in that we can get a leafed out plant to keep its leaves but how do we force the plant to put on new growth? You figure out what the plant needs to send out new growth periodically and you can keep a Japanese Maple alive for up to five to six years and perhaps longer. I believe what you really want is for the seed that comes from that plant to be able to be changed enough to sow the seed outdoors and hope that the plant can yield offspring that can keep their leaves indefinitely. That will not happen. We can change the plants biological time clock but we are not going to change the genetics in the plant to make it eventually produce evergreen offspring. We have to do that on a cellular level and probably will have to introduce another plants DNA into the equation to help us along either by adding a loop of DNA into the host plant by genetic modification or through genetic manipulation in a test tube or in a petri dish and go the tissue culture route and hope we get lucky at some point in time and eventually "breed" an evergreen Maple. We will not have success wanting to force or change the genetics of the plant through selection by altering the plants time clock. That alone will not do it is your answer. Jim
Fresno maples would be of considerable interest to gardeners in Gainesville or Orlando. Some varieties of peaches and, of course, Japanese persimmons, will do well in central Florida. The Morikami Japanese garden in Palm Beach County uses gumbo-limbo (Bursera simaruba) in place of maples. The effect is a bit disconcerting, but the trees should look good as they age. Morikami does have some thriving azaleas, but that's evidently due to providing lots of pine needles.
I think you will have to find out what caused the most trouble for growing Japanese Maples in Florida and work from there. It could very well be that certain cultivars simply will not do well but others might if given a chance. The hard part will be bringing in plants that have clean rootstocks which might have been the problem all along. If that was the case in the past then strive to find a clean growing source for grafted Japanese Maples. Monrovia grown plants sold in various retail nurseries even if they have to come in from nearby states would be worth trying as well. It may even be best to start off with green leaf seedlings and see how they hold up before converting over to the named forms but I think there are some people around that would be willing to work with others in Florida to see what will work, what won't do well and then determine what went wrong if any of those plants perish. I was wondering if the climate is too close to what San Diego and vicinity has in that the climate really never does go cool but the plants will adapt and will go deciduous and will leaf out again in the Spring. It just takes a few trials with plants from clean sources, clean meaning not laden with a disease issue. I think Maples brought in closer to home would be your best bet and there is someone in the UBC BG Maple forum that is a member of the Maple Society from Georgia that may be able to track down some plants that may work for you there. If you can grow some of the Fruit Trees that we have here and can grow some Azaleas you should be able to grow a Japanese Maple in Florida. Like most any experiment there may be some failures along the way but the successes will be worth noting to build on as a foundation and move forward from there. Offhand I envision no reason why Florida cannot grow Japanese Maples but stick to the varieties that are known to be more universal in that they are known to adapt and grow most anywhere. Burgundy Lace is a tough Maple to grow in any warmer climate, whereas true form Bloodgood, Suminagashi, Sherwood Flame for the palmate and deeply divided forms and Crimson Queen, Ever Red, Inaba shidare, Red Select for the red dissectums should be able to tolerate your climate. Viridis and Waterfall for the green dissectums will likely require wind and afternoon sun protection but as long as they get watered often enough and you do not have soil alkalinity issues, they should be able to grow there. Almost forgot, Seiryu is the most adaptable green dissectum of them all and can tolerate full sun, hot winds and saline soils as long as it gets deep watered, for some examples worth trying. Jim
My suspicion is that Eric Schmidt, the horticulturist at Leu Gardens in Orlando http://www.leugardens.org/ would have discovered a good palmate-leafed maple by now. He's certainly found a lot of good East Asian plants, including some evergreen, entire-leaved maples. Orlando gets significantly more winter cooling than the coast, where sea breezes tend to keep the nights warmer. By the way, Leu is working to expand their sasanqua camellia collection. Japonica azaleas are a puzzle this far south. Some old purple ones are living happily in front of an old house on a main street in full sun with no irrigation or attention. Someone else has happy, neglected azaleas that get showered with those acidic South Florida slash pine needles. The japonicas are more reliable just one county to our north, and thrive by the time you get to Daytona Beach. I'm reluctant to mess with them when there's so much other plant material to play with. In the camellia department, that neighbor of mine with the azaleas also has a successful japonica. The buds on my little one never open, so it's being replaced by a couple of sasanquas, which ought to thrive. For "temperate" hardwoods in Florida, I might mention Celtis laevigata, the sugarberry. It grows happily on tree islands (peat substrate) in the Everglades. The southern coast has a few populations of a couple of truly tropical Celtis iguanaea and another species I'm too lazy to remember at the moment. Pop ash, Fraxinus caroliniana thrives in the Big Cypress/Fakahatchee Strand area, right alongside pond apples, Annona glabra. Not to mention all those orchids and bromeliads. Thinking again of Asian plants to play with, I'm trying Satakentia liukiuensis, the feather-leafed Satake palm from the Ryuku Islands and need to put some Easter lilies or Taiwan lilies around them.
As much as I would love to have some palm trees and plumeria, etc. grow in zone 6, Boise, Idaho. But they aren't going to, unless I have a green house and more humidity in our dry desert air. So instead I get to enjoy so many other plants and trees, etc. that won't grow elsewhere. I grew up in the Bay area and we had a Sweetgum Maple tree in our front yard facing west, but getting some southwest sun. It grew tall and beautiful. They try to grow them here and they just don't seem to thrive in our colder, dry climates. Landscapers still try, but I have not seen a sweetgum maple as tall and gorgeous as the one we had in Silicon Valley. I think what frustrates me is that all the plants that could have been planted in our Bay Area home, that was never introduce. If I were home again, with my knowledge I have now, I would grow ferns, Japanese Maples, instead of the one my mother finally planted in a wine barrel by a fountain. I would grow clematis, baby tears, camellias, etc. But I'm happy where I'm at as our temps are pretty moderate for many, many types o f shrubs, conifers, hostas, Coral bells, Japanese Maples, and of course clematis and roses. And I do support the ones that try to grow things in other zones, as an experiment and you just never know what you will find. Also, with micro climates on my property, many tropical plants can grow here. So i hope all works out for you in your tropical maple growing. As said before by other posters and me, you have such an opportunity to grow some very lovely trees and plants that are lacy and gorgeous where you are planted now.
I remember seeing a Purple Beech tree in the parking lot of a Denny's Restaurant in Beaverton, Oregon, right under the street light in the parking lot. At the end of December, I drove by at night, to see a cluster of leaves still purple and alive underneath where the light shines at night. Odds are it's a combination of light and warmth - maybe daylength too, but I'm not certain on the latter.
