Palms and Dicot Trees

[chris.oz]

There is a spectrum in landscapes,  from a traditional landscape with nothing but dicots,   some with just a couple of Trachys in an otherwise dicot garden  through to gardens with palms almost exclusively.

This pretty much mimics nature,  except that in nature,  usually a landscape with palms dominant has palms of only one species.   eg Howea on Lord Howe Island,  whereas us plant "collectors" tend to want to mix in quite a few different species.

Todays trends in landscaping are to have only one or 2 species to get an "architectural" effect.

My preference is for a "lush" tropical look,  with a dicot canopy.

Whats your idea of the best mix ?

[Matt in SD]

Opinions...

Well I think that all the stuff about "good landscapes" having lots of the same plants was just made up by lazy landscape architects who wanted to save time and $$$.  Sure when you're driving by someone's yard at 60 miles per hour, you'll probably get the "effect" more if they have massive rows or swaths of a particular plant, but that looks interesting for about 1/2 second...the time it takes to drive by.  

I like that create a "feel" when you're in them, which can be done by mass plantings of a small number of plants.   But, beyond the instant effect when you go in (i.e. the "feel"), a real memorable garden has more details and interesting things that you can only find after you've gotten past the initial awe.  You can create a "feel" with a small number of different plants, but to me the effect wears off if you realize you've seen it all within the first 5 seconds.

Since 99% of the general public can't tell a CIDP from a coconut, or a banana from a bird of paradise, using a large number of palm species (at least in my mind) still allows for a garden to have a consistent theme, and have good "architecture".  

As for dicot trees, they tend to take up a LOT more space than palms, and also can be challenging because they can spread out so much over time.  I think a ratio of 10 palms to 1 dicot tree is a minimum.  If you start considering miniatures like Chamaedorea and understory Dypsis, you could have 100 palms under a single large dicot tree and it could still look nice.

Well that's my extremely biases opinion.  I am constantly battling my need for more species while still having a somewhat civilized looking garden.

Matt

[chris.oz]

Matt,

Theres fashion in gardening and we are feeling it here,  with our population outstripping the available water,   the fashion is to plant xeriscapes.   There are even suggestions current here to chop down all the elms and oaks in our city.  

One of my problems with limited space available is the spread of Dicksonia antarctica.   Just one of these spreads in a 16 ft circle at a height of 8 ft and really blankets everything.    I am seriously considering thinning out the fronds,  to let light into the understory.

Once trees get too high,  thinning them requires a cutter on a stick,  and use this to thin out the canopy,  but that jobs mostly done by possums on a number of species.

[DoomsDave]

I'm shooting for about 99% palms, at least in terms of individuals.

Diversity, schmiversity . . . . DAve

[Jeff Searle]

Chris,

    My preference is also the lush look mixed with large trees. I want lots of shade in my yard. I work enough in the sun, so when I come home or when Andrea and I entertain, I want the jungle feel. T R O P I C A L !

[bgl]

Chris,

In those areas here where I had a choice I have definitely planted palms ONLY (Clinostigmas, Carpoxylons, Dypsis, Kerriodoxas, Iriarteas, Euterpes just to mention a few) and these are now all at a size where I have canopy. However, I have also utilized the existing local endemic "ohi'a" tree (Metrosideros polymorpha). Even though we did cut down a number of them, for various reasons, we also kept many of them (probably more than 100), so we have sort a mixed look. Here's part of my Dypsis sp. "orange crush" canopy.

Bo-Göran

[Bilbo]

How many palms grow naturally in a palm monoculture?

Aswer surely is: usually none.

Case in point : the Pseudophoenix ecmannii in Jaragua were a wonderful forest but were accompanied by all sorts of other things even vanilla orchids!

Botanic gardens too usually have a wide diversity of palm/dicot and surely this is right ??

Just my thoughts.

Regardez

Juan

[tikitiki]

I plant palms. I want palms for a canopy, understory, mass plantings and for specimans. Then I throw in a few plumaria and heliconia for color and fragrance. I do it for me to enjoy not for the HOA.

[Kris]

Dear Matt in SD  

Very well said.i too support your opnion.

Kris.

[DoomsDave]

(bgl @ Nov. 10 2006,01:58)

QUOTE

Chris,

In those areas here where I had a choice I have definitely planted palms ONLY (Clinostigmas, Carpoxylons, Dypsis, Kerriodoxas, Iriarteas, Euterpes just to mention a few) and these are now all at a size where I have canopy. However, I have also utilized the existing local endemic "ohi'a" tree (Metrosideros polymorpha). Even though we did cut down a number of them, for various reasons, we also kept many of them (probably more than 100), so we have sort a mixed look. Here's part of my Dypsis sp. "orange crush" canopy.

Bo-Göran

OUCH!

Said the Swooning Sofa . . . .

dave

[Alberto]

In our native Araucaria forest the proportion PalmsXdicots is +- 1 queen palm/ 100 dicots. I plant them at a rate of 1 palm to 5 or 10 dicots.... That gives the natural look in my eyes....

[Alicehunter2000]

(Jeff Searle @ Nov. 09 2006,23:34)

QUOTE

Chris,

    My preference is also the lush look mixed with large trees. I want lots of shade in my yard. I work enough in the sun, so when I come home or when Andrea and I entertain, I want the jungle feel. T R O P I C A L !

I agree...........Shade is a big issue in my yard and in the front yard I have issues with power lines and underground utilities. Additionally, my palate of mono and dicot is severely restricted due to my 8b/9a zone.

I use alot of Sabal's in many areas for instant canopy. I can buy here for $150 for 20 ft. ct palms.

I would think this discussion might include % of overhead space as opposed to number ratios of types of dicot trees/palms.

1 mature live oak/10 rhapsis sp. gives quite a different dicot/monocot ratio and subsequent "look" than say 1 Mimosa/10 adult Phoenix canarsis.  

David

[Alicehunter2000]

Actually it is the same ratio ..........but different look......you all know what I mean.

[amazondk]

Here in our area, Amazonia, the forest understory has in many places a high population of palms.  In addition there are normally a large population of palms which penetrate the forest canopy.

Here are a few images of palms in the native forest.

This is a Jatoba tree in the background (Hymenaea courbaril).

[Dave-Vero]

Ohi'a lehua (Metrosideros polymorpha) is not only Hawaii's pedominant native tree, it feeds the native birds.  Definitely a must for a Hawaiian garden!

I'm installing a shaded bed of Rhapis (including R. laosensis from the Searle Extravaganza), a Zamia variegata, and probably some native wild coffee.  Smithsonian at Ft Pierce

[Zac in NC]

Well, considering my zone, its a ratio of about 1 palm to 20 dicots. I am working on it, but there are only so many species I can plant. When I do get to someplace tropical ( my mantra), I plan to plant tons of palms, as well as uber-cool dicots. I think it'll be a 1 to 1 ratio.

Zac

[bgl]

Dave,

Yes, I agree, the Ohi'a lehua is a must for a Hawaiian garden since it's native here. All by itself, however, it's not a good canopy tree since they tend to be fairly tall and skinny. But when you have a whole forest of them, you obviously have enough of a canopy. Here's a photo from the forest right next to us, showing all Ohi'a trees (but no palms - not yet anyway!).

Bo-Göran

[bgl]

Another tree that's also native here, but MUCH more unusual is more of what we think of when he hear the word "canopy tree". This is a Tetraplassandra hawaiiensis, quite unusual here. We only have 3 on our property, and I have only found a handful in the vast forest behind us. These are massive trees with a canopy that extends a good distance away from the main trunk. There are two that are visible in this photo (one exactly in the center, and the other one is the canopy you see on the left), and I have used them primarily as a canopy for a whole bunch of Marojejya darianii palms.

[Dave-Vero]

bgl, how native is that forest?  It's fantastic that you have o'hia on the property rather than just African Tulip Tree (Spathodea campanulata), Schefflera, or even Clusia rosea from the Bahamas strangling the Queensland Scheffleras.  

Tetraplasandra looks like a neat native, to judge from this Smithsonian site:

http://ravenel.si.edu/botany....ult.cfm

Hakalau Forest National Wildlife Refuge has been working hard at restoring its Big Island rain forest and trying to keep Miconia out or at bay.

[bgl]

Dave,

Well, the Ohi'a forest here in the Puna district covers large areas, but what is large to us would be fairly small on the U.S. mainland. I have never counted them but I'm sure we have at least 100 Ohi'a trees on our five acres. Maybe even 150. Then in addition to that we're leasing a good chunk of land adjacent to our property,  from Kamehameha Schools, in order to set up our palm nursery. There's nothing in the contract to prevent us from cutting down whatever we want in order to set up the nursery, but I located a few fairly open areas, and used one of those for the shadehouse, so we only had to take down a very small number of trees, and 99.9% of the forest is intact, and there must be tens of thousands of Ohi'a trees just on the land that we're leasing. Here's the same area that I posted in the pic above, but from a different angle. Most of the trees are about the same size and height, but we do have some real big ones here and there. This was of course one of the areas that we opened up, and added the red cinder, but we only had to take down a handful of trees. The rest will remain as they are. Incidentally, we have no African tulip trees, and even though Miconia is a problem not too far away from us, it's never been a problem on our property, and I have never seen it on the land we're leasing.

[bgl]

And I have also built a few paths through the forest. Otherwise it would be extremely difficult to gain access to it, or enjoy it. Terrain is uneven to say the least, and without a compass (or GPS I guess!) you'd be lost in less than a minute. In the area in this photo I decided to open up a larger area (all by hand) and bring in the red cinder with a wheelbarrow. The only vegetation I took down was Tibouchina, which is a real invasive nuisance. All the native Ohi'a trees, and a few other smaller native trees, will remain exactly the way they are. Since we have the lease I can control exactly what's happening on this piece of land. For a LONG time!

[amazondk]

Bo,

What families of trees are most common in the native forest there?  Here we have a lot of Lauraceae, Sapotacae, Annonaceae, and Leguminosae (these tend to be the some of the tallest emergent trees).  There is a forest reserve which borders on town here called Ducke.  This area is a protected study area of 100 km2.  They have catalogued 1176 species of dicots and 43 species of palms in the area.  I don't know though what the percentage would be of palms per area in the forest.

Here is a link to the Projeto Flora at Ducke Projeto Flora - Reserva Ducke Manaus, AM

dk

[bgl]

Don,

Well, the most common tree here by FAR is the Ohi'a Lehua (Metrosideros polymorpha), a fairly tall tree that's slow growing and has VERY dense wood. I'd say 99.9% of all the tall trees in the forest next to us are Ohi'as. The remaining 0.1% would be Tetraplassandra hawaiiensis. Then, there's also quite a few smaller "Kopiko" trees (Psychotria grandiflora), and that's pretty much it for the native trees. Unfortunately, in certain parts there are also thousands of invasive Strawberry guava trees, and they are tough to cut down (wood is hard). The Tibouchina is also a nuisance but those are easy. A couple of whacks with my machete and I can take down a 25 ft tall Tibouchina in 15-20 seconds. The Guava is a different story.... In addition to the regular trees, there are also quite a few native Hawaiian tree ferns (Hapu'u and Ama'u - I forgot the botanical names). No palms (other than the ones I'm going to plant!).

Bo-Göran

[amazondk]

Bo,

Was the pre-human contact forest more diversified?  I would imagine that since the islands are not all that old geologically and are in the middle of a very big ocean it would take a long time to evolve into a compex forest.

dk

[Dave-Vero]

Bo,

You've got a wonderful situation.  Great to hear that you have only limited pest plant problems, although guavas can be a handful--we have regular and strawberry guavas here, too.  If only there were a healthy market for guava wood.  Annoyingly enough, guavas are a mess to grow for fruit here--fruit flies.  Got to wrap each fruit.  

The Hawaiian Islands have been around for millions of years, but the number of plant species that managed to colonize such remote islands was very small.  I think the estimate is around 200.  Some of the plants seem to have colonized what are now the Northwest islands when they were much larger, then colonized Kaua'i and the younger islands as they popped up. There isn't much tree species diversity, but O'hia makes up by being amazingly variable.  The specific epithet "polymorpha" is approriate.   The islands are among the very best places to see island evolution at work.  Silverswords are charismatic examples.

Thanks to rampant evolution, plant systematics in Hawaii is sort of a challenging business.  Robert Read explained that when he finally got funds to study Hawaiian Pritchardia, it turned out that several alleged species didn't hold up, but he managed to discover several new ones!

[bgl]

Don and Dave,

Yes, the situation here in Hawaii is pretty unique. However, I can't see how the pre-contact forest here could have been more diverse, and nothing I've read would indicate that this was the case. The Big Island's age is estimated at 750,000-1 million years, and the first humans only arrived here about 1600 years ago (from the Marquesas), so the forest back then probably looked pretty much the way it does today. Well, other than the fact that they didn't have any guava or Tibouchina!

I believe the forest in the photos above is primary virgin forest in an area that has never been harvested.

Bo-Göran

[chris78]

I am trying to make my own tropical forest... as of now I am using 2/3 dicots to 1/3 palms. I am planning to put more understory palms over the next few years. I want a rainforest look with tall dicots with lots of understory palms.

[amazondk]

Bo,

Which Tibouchina is the one that is causing trouble in Hawaii.  There are many varieties here,  and I think most are secondary.  The tibouchina - Tibouchina granulosa, is used extensively in Southern Brazil as a landscape tree and is also used for reforestation projects of native forest on the coast of Sao Paulo as it is a secondary species that is overtaken as the forest matures.  Of course this would not be the case in Hawaii where there is no complex primary forest.  We have several species here which are not major impacts on forest regeneration but are always found in secondary forests.

Chris, That looks nice.  And, I am sure it will give you the desired effect.

dk

[Dave-Vero]

HEAR (Hawaiian Ecosystems at Risk) lists these Tibouchinas as established in Hawaii.  http://www.hear.org/

Tibouchina herbacea (Melastomataceae)  NOT native to Hawaii  PRESENT in Hawaii  ESTABLISHED in Hawaii  

http://www.hear.org/pier/species/tibouchina_herbacea.htm

Tibouchina longifolia (Melastomataceae)  NOT native to Hawaii  PRESENT in Hawaii  ESTABLISHED in Hawaii  

Tibouchina urvilleana (Melastomataceae)  NOT native to Hawaii  PRESENT in Hawaii  ESTABLISHED in Hawaii  

http://www.hear.org/pier/species/tibouchina_urvilleana.htm

Then there's Miconia, the nightmare plant.  http://www.hear.org/MiconiaInHawaii/

____

But Tibouchina granulosa isn't a problem!  http://www.hear.org/starr....osa.htm

[amazondk]

Dave,

That is intersting stuff on the web site.  Brazil has certainly contributed a lot to invasive species from fire ants to trees.  

dk

[bgl]

Dave,

Thanks for answering that question better than I could have! However, despite the photos and info I can't quite figure out which one we have here! This is what the flower looks like.

Bo-Göran

[Dave-Vero]

Unfortunately, the entire family (Melastomaceae) has very similar-looking flowers and leaves.   To us Floridians, your plant looks like a Rhexia on steroids.

There's nothing particularly evil about the Brasilian flora.  The Pacific Islands, like other islands, happen to be vulerable to invasion.

[amazondk]

Bo,

Has the Cercropia tree made an impact there in Hawaii?  Here this is the prime colonizer in the formation of secondary forests upon regeneration.  It is known locally as imbauba.  The toucans love the fruit and probably help in seed dispersal, since we have a lot of toucans around.  I would suppose that those trees most invasive of a place like Hawaii would be the secondary forest first colonizer regeneration group.  Since they do not have the larger trees that move in forming a complex forest system in conversion back to primary forest they would tend to take over.  Here they get shaded out and disappear.

dk

[bgl]

Don,

I pulled up a photo thru Google of a Cercropia, and the leaves look familiar to a tree that I have seen here and there in the neighborhood. It's definitely an exotic tree, and it gets to be rather tall, maybe 40 ft or so, with a clean trunk, maybe 8-12 inches in diameter, and a canopy-like crown. If that's a Cercropia I wouldn't call it invasive because it doesn't seem to spread but so much. I chopped down a big one in the forest a few months ago, and the wood was fairly soft so it was pretty each to take down. I don't have a photo on file of one.

Bo-Göran

[amazondk]

Bo,

This picture was taken last year in th forest as I was going in to check out some trees.  If you look to the left of the guy going into the forest you will see some big leafed tree.  It has a very slender trunk.  This is a small specimen, they get maybe up to 40 or 50 feet (the primary forest canopy in the area is from 150 to 180 feet high).  This spot had been cleared for a garden type plantation, manioc, bananas and the like, . They have hollow trunks and are very soft wood.  There are many varieties of thiis tree in the region.  The things grow very fast, and have a short lifespan.  That day was an exceptonally bad walk, for one I drank too much local firewater the night before, and two there was a lot of high secondary forest to go through, which is tough going.  You end up crawling over, through, and under all kinds of undesireble vegetation.   And, it was extremely hot to boot.