Looking for trees that look tropical or prehistoric zone6

I have had a interest in possible trees that look more tropical but can handle our winters. I have a growing list but was interested to hear what others have grown.

You could attempt a Monkey Puzzle Tree (Araucaria araucana) http://davesgarden.com/guides/pf/go/1452/ with very careful placement and added protection. From my own observations, they despise hot/dry summer conditions and winter cold/dry winds. They would probably benefit from placement in a north facing, shaded location with protection from a building. They benefit from cool-humid conditions, take snow and cold conditions to a point. Visitors to this area find this tree to be the most exotic looking, unusual tree beside the Chinese Windmill Palm, which can also survive with proper protection.

This is the recently planted tree across the street from me in last winters cold snap. It's doing quite well.

I have tried this a few times and we had some that did very well. It seemed that ones we got from a certain nursery did much better than others we had from another nursery. Possibly different clones are tougher than others.

Yes. I would suspect seedlings from trees of Argentinian origin to be hardier to drought than Chilean. Too bad it's so impossible to import seed. I can't even export seed from here! There are ski resorts amongst the Araucaria http://www.travelsur.net/ski/Caviahue/cavipic2.jpe .

The seed of Trachycarpus fortunei that I've supplied to a seed house in Massachusetts, where they did a test plot, the seedlings did very well compared to warmer climate origin seed. I'm surprised the seed increased hardiness but then the seed are held over winter and harvested in spring.

Monkey-puzzle can't be relied on at all in zone 6, it is even very marginal in zone 7. Denmark (zone 7) lost every single one in a severe winter a few years ago.

Resin

Monkey-puzzle has been killed a lot of times in KY - both Louisville and Lexington, where we experience exactly the conditions that growin remarks that Monkey-puzzle hates. Buy big ones, and plant them as annuals - if you are into botanical torture.

Among native or more common species that you are most likely already familiar with, but could be considered appropriate for the context you ask about, are these plants:

Aralia spinosa, though a colonizing type grower, has a very tropical feel with the large thrice-compound foliage and "prehistoric" look to the bare spiny stems in winter.

Gleditsia triacanthos likewise has a terrifying character in winter, baring its sheathing of large tripartite thorns.

Gymnocladus dioicus has large (up to tripinnate) compound foliage that can have a jungle-y feel when well-grown. Pruned, it can exhibit quite different character than a fence row tree with its stark branching architecture.

Many of the taller Rhus spp. (R. typhina, R. glabra, R. copallina, R. chinensis) provide a tropical feel with the stemmy colonizing behavior and large compound foliage, as would the five or six species of Carya and the couple of walnuts (Juglans spp.) that do well in KY.

Rhododendron maximum and Magnolia grandiflora are often overlooked for this type of application, since most Southern magnolias and broadleaf rhododendrons are often trained as rather formal or symmetrical plants. These big broadleaf evergreens can be as tropical as the next guy, but totally hardy in KY.

Maclura pomifera (and its thornless selections like 'White Shield') often has an otherworldly feel, especially old plants, with its arching and craggy canopy (and those big cannonball fruit on the female forms).

Finally, among local natives, Asimina triloba is a great full sun or full shade smaller tree with its large pendant leaves that look like they came from some place tropical.

OK, how about some freakish plants that I don't know much about growing, but look like that they fit your bill?

Eleutherococcus senticosus and Eleutherococcus divaricatus (members of the Shrub-Ginseng bunch, possibly formerly Acanthopanax?) are some devilishly thorny plants that I've only seen once, this past September up at the Morton Arboretum in Lisle IL outside Chicago. Should be hardy enough. Since I only saw them in leaf as large sprawling shrubs, I can only imagine what they'd be like in their dormant form (and some landscape pruning for form to reveal some of that branching architecture).

Helwingia japonica, where the plants flower appears from the midrib on the upper surface of its simple leaves. Also observed at the Morton, but I have no other experience with this oddity.

I've got to mention Oplopanax horridus, a Pacific northwest native that growin should know, just because of its great name.

I'd be remiss if I didn't at least suggest some Viburnum species...

Viburnum sieboldii has done well in KY. There are large old specimens on estates in east Louisville, and its large foliage starts to give the feel of Asimina on a plant that can have much more of a droop to its canopy.

Viburnum rhytidophyllum and its much more vigorous offspring V. x rhytidophylloides will with age develop some of the characteristics that you are after, especially if they are not heavily sheared into dense balls.

Many of the pendulous/weeping and contorted/twisted/tortuous selections of native or locally hardy plants can also be evaluated against your criteria. The recent introduction Nyssa sylvatica 'Zydeco Twist' is one example.

Interesting topic! You might also refer to Frederick Law Olmsted, Sr.'s writings about the effect he was designing for along the 3 mile entrance drive into the Biltmore Estate for George W. Vanderbilt back in 1895. I remember reading some of this, and his explicit intent was to provide a sense of lush tropical richness through the plant selection, massing, and placement.

Additionally, though this is probably one of your normal haunts - take a walk through the landscapes planted at the Louisville Zoo (and other cities' facilities) for inspiration on how their horticulturists generate habitat feel with locally hardy plants. Lots of interesting ideas coming from members of the society of American Zoo Horticulturists.

I'll be interested in what other plants are suggested here.

For deciduous try Albizia julibrissin. 'Summer Chocolate' is particulary attractive. It is considered invasive in some zones. Since your zone would be a bit of a stretch it might alleviate any invasiveness.

http://davesgarden.com/guides/pf/go/56536/

This has been a really interesting read. Thanks. Does Albizia really survive zone 5 b winters?
One that I've got here in zone 8a ( or b or something) is Trochodendron aralioides. A lovely evergreen with a certain exotic strangeness that survives here no probs but is reputedly much much hardier still.

VV's got some great suggestions and Mr_Canthus's suggestion of Trochodendron, if hardy enough, would work. My experience with Oplopanax horridus is that it has shredded arms, legs, etc in the bush but it does have merit as an exotic ornamental. It is found in mostly muddy/stream situations. I've read online that Musa basjoo can survive if specially protected in z6.

Wow! wouldn't it need an electric blanket and a hot water bottle. We have to mollycoddle it here.

Another one I guess is Eriobotrya japonica... its absolutely fine here but I'm not sure how cold it can get

The Bigleaf Magnolia, Magnolia macrophylla, is very tropical-looking with leaves up to 32" long and a foot wide! Also, the cutleaf sumac cultivar 'Tiger Eyes' is absolutely stunning, bright gold in full sun, with flaming fall foliage colors. Both are perfectly hardy in your zone.

All those wild ravings from the Pacific Northwest and from across the pond have stimulated a few more synapses...

All the local deciduous larger leaved magnolias would fit in the tropical/prehistoric feel category, including:

•Magnolia macrophylla
•Magnolia tripetala
•Magnolia pyramidata
•Magnolia fraseri
•Magnolia ashei (sometimes not considered a separate species)

That Trochodendron aralioides is one weird chap...

Overlap alert! HG slipped in ahead of me...

M. ashei blooms when much younger and has the large leaves so might as well go for that instead of M. macrophylla. With the Trachycarpus, best to buy a large quantity of seed from a cold source and plant out. Direct seed, some winter protection and the hardy ones will make it.

Back to the Araucaria - it is one of the few conifers that can be chopped to the ground and regrow. If there's a bad winter that fries the top, don't give up on the roots/stem.

Some great suggestions/discussion.

to add...Yucca glauca, Y. whipplei, Wingnuts (Pterocarya sp.), poncirus trifoliata, Aralia elata, Eucommia ulmoides

M. ashei is similar to M. macrophylla, but the former's leaves are smaller and it is not as cold-hardy. It should be fine in Zone 6 though. Here's a photo of M. macrophylla.

These are some great ones for me to search out. I have looked up most of them before but a few are new to me. I have been looking into the wingnut trees they interest me. I personally like the M. macrophylla better but have not found a good source for seeds or small plants yet. I really look forward to hearing more suggestions and the photos of them are great to see.

Here is a pic of the Chinese Parasol tree. I am growing a lot of these out this season they are very hardy and have a very tropical look to them.

There is a massive old specimen of Pterocarya fraxinifolia in Cave Hill Cemetery - just visited it while leading a KLI tour last week in the snow. Still had seeds hanging from it. I've grown this one successfully here, till the abominable 2007 Easter freeze nailed my big plant while it was in full leaf. It had produced prodigious seed the previous year, and many sprouted after that Easter disaster. Those progeny are growing all over around here, many sprouting in container plants' media.

Firmiana simplex is a fun one I've not tried yet, but know of a friend at the Cox Arboretum in Dayton that grows new seedlings regularly from a parent plant there.

Seems like Magnolia macrophylla seed wouldn't be hard to come by. Maybe need to join the Magnolia Society and make friends there. I know Bob Adams grows this and M. ashei up in Shelbyville, IN.

I forgot about the Chinese Parasol Tree. The reason I suggested M. ashei over M. macrophylla is that it blooms when much younger and is a much more sale-able product with blooms in a 5gal than a M. macrophylla which takes much longer to bloom. If it's just foliage, M. macrophylla is great.

How about Ficus carica 'Chicago' or Davidia involucrata?

This message was edited Jan 19, 2010 11:56 PM

Not in this case.

The young plants to which I refer are seedlings growing in the containers' media - not attached to the parent plant. I've transplanted some of them, when the original container plant was ready to go in the ground.

The original parent tree made feeble attempts to sucker along the trunk and branches after the 2007 Easter freeze, but the cellular explosion of the bark throughout the tree devastated it.

I don't think I've ever seen root sprouts from this plant. It would have had opportunity to do so in nearby mulched beds.

There's no end to this is there? Really marvelous. The prehistoric look is an interesting thing; Thujopsis dolobrata always conjures up thoughts of dinosaurs in my mind and I've never known it as anything other than really hardy

How about Ginkgo biloboa? The most ancient tree, speaks prehistoric to me, although not especially tropical looking. Beautiful, though.

How about one of the many Sciadopitys? Both tropical and prehistoric to me. I have 'joe kozy' and 'hange form' (pendulous) doing fine in Chicago....

I'm not sure how "tropical/prehistoric" this might be considered but Acer macrophyllum is hardy and has quite large leaves. Makes an impressive tree with age and grows relatively fast. They are now making maple syrup with it locally.

Here's the dissected leaf form: Acer macrophyllum 'Kimballiae'

Wow very interesting and I had not heard anything about this one. Anyone know of a source for it?

Forest Farm has it:

http://www.forestfarm.com/product.php?id=134

Has any of us said Liriodendron tulipifera... if not, its probably because it goes without saying..... except it doesn't because I've just said it............. sorry

Yeah! didn't think of that

I think cunninghamia lancifolia looks like it comes from another time zone.
It's been perfectly hardy here in Z6. Mine is 30ft tall, I think.
I was looking for photo, but all I have is photo of the textured bark.
It's a conifer w/ spiky foliage. Come to think of it, spiky bark too!

Liriodendron tulipifera is extremely common in the Midwest, but much appreciated. 150 years ago, it was a very valuable tree for lumber, and still is. But, most of the giants from the virgin forests are gone.

Wonderful thread--thanks so much everyone. I was particularly glad to see the gingko recommendation--that was the first "ancient" that came to mind.