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Vinc

Invasive palms in your region

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Vinc

Hey all,

I'd like to know what palm species are naturalizing or even invasive in your region. Photos would of course be nice. :)

In Switzerland, we have Trachycarpus fortunei spreading on the southern site of the Alps in moist forests and building self-sustaining populations.

Cheers, Vincent

 

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IMG_1026.thumb.JPG.73cbc50d60b3bd9f6c638

IMG_0523.thumb.JPG.2166ea3428466bddf28e0

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PalmatierMeg

Here in SW FL queens, Syagrus romanzoffiana, are considered Class II invasives, which means while they aren't banned from sale in stores they are discouraged from use as landscape plantings. And I've seen them replaced in new commercial, residential and median plantings. Now they are sold at BB garden centers to individual homeowners who just want a cheap palm to stick in the ground. They don't like our alkaline soil and as most people never fertilize them they eventually decline and die. Washingtonia robusta is also way overused as a landscape palm because it is fast and cheap. I have a feeling fusarium wilt may take out both of these unsuitable species.

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tjwalters
1 hour ago, PalmatierMeg said:

Here in SW FL queens, Syagrus romanzoffiana, are considered Class II invasives, which means while they aren't banned from sale in stores they are discouraged from use as landscape plantings. And I've seen them replaced in new commercial, residential and median plantings. Now they are sold at BB garden centers to individual homeowners who just want a cheap palm to stick in the ground. They don't like our alkaline soil and as most people never fertilize them they eventually decline and die. Washingtonia robusta is also way overused as a landscape palm because it is fast and cheap. I have a feeling fusarium wilt may take out both of these unsuitable species.

Years ago I saw a really nice queen growing wild amid the native flora in a natural area of Hugh Taylor Birch State Park.

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CroToni
2 hours ago, Vinc said:

Hey all,

I'd like to know what palm species are naturalizing or even invasive in your region. Photos would of course be nice. :)

In Switzerland, we have Trachycarpus fortunei spreading on the southern site of the Alps in moist forests and building self-sustaining populations.

Cheers, Vincent

 

IMG_1382.thumb.JPG.32a402075d6e8082e29e4

IMG_1026.thumb.JPG.73cbc50d60b3bd9f6c638

IMG_0523.thumb.JPG.2166ea3428466bddf28e0

In coastal north Croatia,no palm species is invasive,however robustas,trachies and mediterranean fan palms are easy to find in the forests,growing on beaches,in cracks etc.

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CroToni

Also it is incredible that they grow there,I go skiing in the swiss alps and it gets crazy cold.Once we had to stop skiing because it was -29 degrees celsius.

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topwater
3 hours ago, Vinc said:

Hey all,

I'd like to know what palm species are naturalizing or even invasive in your region. Photos would of course be nice. :)

In Switzerland, we have Trachycarpus fortunei spreading on the southern site of the Alps in moist forests and building self-sustaining populations.

Cheers, Vincent

 

IMG_1382.thumb.JPG.32a402075d6e8082e29e4

IMG_1026.thumb.JPG.73cbc50d60b3bd9f6c638

IMG_0523.thumb.JPG.2166ea3428466bddf28e0

Is this considered good, bad, neutral, by the local biology types?

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Kim

Wow, invasive palms in Switzerland? That's crazy! :o:P

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CroToni
57 minutes ago, topwater said:

Is this considered good, bad, neutral, by the local biology types?

 

neutral I would say,their cold fronts will wipe them out,maybe in 5,maybe in 10 or maybe in 15 years,but most if not all of them will die.

they are hardy to 5f for short periods of time that place probably goes below 0 deg fahrenheit every now and then.

Edited by CroToni

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bgl

Archontophoenix alexandrae palms have definitely naturalized here on the Big Island of Hawai'i. :)

2008-03-15 015.jpg

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CroToni
46 minutes ago, bgl said:

Archontophoenix alexandrae palms have definitely naturalized here on the Big Island of Hawai'i. :)

2008-03-15 015.jpg

that looks heavenly.They are prettier than cocos when grown in such an amazing climate.

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TexasColdHardyPalms
3 hours ago, CroToni said:

 

neutral I would say,their cold fronts will wipe them out,maybe in 5,maybe in 10 or maybe in 15 years,but most if not all of them will die.

they are hardy to 5f for short periods of time that place probably goes below 0 deg fahrenheit every now and then.

They are more cold hardy than that. I posted a pic of ten recently transplanted fortunei that went through -5f last year in amarillo, tx and have grown a full head of leaves over the summer.  Zero spear pull, just defoliated.

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Silas_Sancona

While im not sure I myself would consider them invasive, you can spy scattered Washingtonia ( likely robustra) here and there along the Salt River near downtown Phoenix and the airport with a good eye while passing over the river via i-10. This falls in line with other localized escapees which exist around parts of Southern CA. Can also recall the occasional Mex Fan turning up near neighborhood creeks around south San Jose. Seedlings of both droppred by Grackles easily sprout in pots around the yard.

If not removed, it would be interesting how far any future seedlings from the specimens near Sky Harbor are able to spread into areas along the Salt/Gila River southwest toward Gila Bend, or beyond. While to hard to say whether or not either species grew here long ago, it certainly isn't beyond the ream of possibility thus.. perhaps these escapees are just re-colonizing old territory,  or pioneering new turf, with some extra help ofcourse.

Certainly wouldn't mind seeing any of the Brahea,  Montezuma Cypress, or groups of escaped Sabal uresana start growing along the river bottoms here either. :D

 

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PalmTreeDude
1 hour ago, Silas_Sancona said:

While im not sure I myself would consider them invasive, you can spy scattered Washingtonia ( likely robustra) here and there along the Salt River near downtown Phoenix and the airport with a good eye while passing over the river via i-10. This falls in line with other localized escapees which exist around parts of Southern CA. Can also recall the occasional Mex Fan turning up near neighborhood creeks around south San Jose. Seedlings of both droppred by Grackles easily sprout in pots around the yard.

If not removed, it would be interesting how far any future seedlings from the specimens near Sky Harbor are able to spread into areas along the Salt/Gila River southwest toward Gila Bend, or beyond. While to hard to say whether or not either species grew here long ago, it certainly isn't beyond the ream of possibility thus.. perhaps these escapees are just re-colonizing old territory,  or pioneering new turf, with some extra help ofcourse.

Certainly wouldn't mind seeing any of the Brahea,  Montezuma Cypress, or groups of escaped Sabal uresana start growing along the river bottoms here either. :D

 

Like these? Could any be Washingtonia filifera?

 https://www.google.com/maps/@33.4163053,-112.0299561,3a,15.5y,266.86h,84.02t/data=!3m7!1e1!3m5!1soi6NgoYxJjJKlhFtscRhiA!2e0!6s%2F%2Fgeo3.ggpht.com%2Fcbk%3Fpanoid%3Doi6NgoYxJjJKlhFtscRhiA%26output%3Dthumbnail%26cb_client%3Dmaps_sv.tactile.gps%26thumb%3D2%26w%3D203%26h%3D100%26yaw%3D263.56888%26pitch%3D0%26thumbfov%3D100!7i13312!8i6656

Edited by PalmTreeDude
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Cikas
3 hours ago, TexasColdHardyPalms said:

They are more cold hardy than that. I posted a pic of ten recently transplanted fortunei that went through -5f last year in amarillo, tx and have grown a full head of leaves over the summer.  Zero spear pull, just defoliated.

Texas has dry climate. Palms are more cold hardy in dry conditions. 

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TexasColdHardyPalms
48 minutes ago, Cikas said:

Texas has dry climate. Palms are more cold hardy in dry conditions. 

That is a gross generalization that isnt true for much of the state. None the less those palms has 1/4" of rain, ice and then snow 24 hours prior to that low of -5f. 

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Silas_Sancona
50 minutes ago, PalmTreeDude said:

More than likely, these are W. robustra, which are planted everywhere here, but I do plan on taking a closer look at those that are along accessible spots along the river. ( I think area closest to the airport are off limits..would be my assumption anyway) Not out of the question that some filifera or hybrids might be mixed in there somewhere.

Curious if there might be some sort of pattern, ie:  maybe these scattered specimens originate from seed dispersed off palms planted near the Zoo/ Papago Park that washed down into the river, etc. Then again, being that both sp. are planted extensively all over town ( esp. Mex Fans)  its as likely that those that are planted in parks, commercial landscapes, etc closest to the River are seed sources.. interesting regardless. 

Another good Google spot to see other "renegade" groups is from where Priest dr crosses the river, just north of Rio Salado, just below Tempe Town Lake( east of this spot along the river). 

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DoomsDave

We don’t really have invasive palms as such here in So Cal. I guess you could say  the Washies are, sort of though they’re arguably returning natives.

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CroToni
8 hours ago, TexasColdHardyPalms said:

They are more cold hardy than that. I posted a pic of ten recently transplanted fortunei that went through -5f last year in amarillo, tx and have grown a full head of leaves over the summer.  Zero spear pull, just defoliated.

can they survive -20 deg Fahrenheit with a lot of snow?Even though this is a warmer region so their snaps will be closer to -10deg Fahrenheit.I am sure that those temps will knock most out.which is sad because they are beautiful.

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hbernstein

In Florida, Ptychosperma elegans is on the official list. Washingtonia robusta and hybrids, Phoenix reclinata and its hybrids also pop up in unwanted places. African Oil Palm, while not that commonly planted, is also a species that is weedy and spreading locally.

I strongly recommend not planting and attempting to eliminate individuals of any of these species in southern and central parts of the state. With warming climate, they have nowhere to go but north.:(

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TexasColdHardyPalms
8 hours ago, CroToni said:

can they survive -20 deg Fahrenheit with a lot of snow?Even though this is a warmer region so their snaps will be closer to -10deg Fahrenheit.I am sure that those temps will knock most out.which is sad because they are beautiful.

"neutral I would say,their cold fronts will wipe them out,maybe in 5,maybe in 10 or maybe in 15 years,but most if not all of them will die.

they are hardy to 5f for short periods of time that place probably goes below 0 deg fahrenheit every now and then.

Edited 20 hours ago by CroToni"

 

Your quoted temps keep fluctuating all over the place.  A lot of people use the data/information from this forum so please try and be as accurate as possible so that folks in the future can be sure of what they are reading.  Trachycarpus will not survive -20f, but i do know for a fact that mature specimens will survive -5f and snow/ice. 11 of these went through this and every single one lived.  That is an observed fact and important to this thread. 

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CroToni
4 hours ago, TexasColdHardyPalms said:

"neutral I would say,their cold fronts will wipe them out,maybe in 5,maybe in 10 or maybe in 15 years,but most if not all of them will die.

they are hardy to 5f for short periods of time that place probably goes below 0 deg fahrenheit every now and then.

Edited 20 hours ago by CroToni"

 

Your quoted temps keep fluctuating all over the place.  A lot of people use the data/information from this forum so please try and be as accurate as possible so that folks in the future can be sure of what they are reading.  Trachycarpus will not survive -20f, but i do know for a fact that mature specimens will survive -5f and snow/ice. 11 of these went through this and every single one lived.  That is an observed fact and important to this thread. 

I think that the average trachy is hardy to around 5f,but that area of the alps goes below 0f every year atleast a few times,but once every 4-5 years it gets significantly colder.I am sorry for complicating the matter.(in conclusion their average absolute winter low is around 0f,but their cold snaps bring temps that are much colder.In other words I doubt their long term survival.

4 hours ago, hbernstein said:

In Florida, Ptychosperma elegans is on the official list. Washingtonia robusta and hybrids, Phoenix reclinata and its hybrids also pop up in unwanted places. African Oil Palm, while not that commonly planted, is also a species that is weedy and spreading locally.

I strongly recommend not planting and attempting to eliminate individuals of any of these species in southern and central parts of the state. With warming climate, they have nowhere to go but 

20 hours ago, TexasColdHardyPalms said:

They are more cold hardy than that. I posted a pic of ten recently transplanted fortunei that went through -5f last year in amarillo, tx and have grown a full head of leaves over the summer.  Zero spear pull, just defoliated.

 

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PalmTreeDude

Those have had to have been there for a while now, if they are self sustaining. The one on the edge of the cliff looks pretty old since it started from seed. It is almost like they formed their own hardy ecotype, endless they get defoliated every year, which it appears they don't. 

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Vinc

Thanks for the many replies!

On 17.12.2017, 15:42:16, PalmatierMeg said:

Here in SW FL queens, Syagrus romanzoffiana, are considered Class II invasives, which means while they aren't banned from sale in stores they are discouraged from use as landscape plantings. And I've seen them replaced in new commercial, residential and median plantings. Now they are sold at BB garden centers to individual homeowners who just want a cheap palm to stick in the ground. They don't like our alkaline soil and as most people never fertilize them they eventually decline and die. Washingtonia robusta is also way overused as a landscape palm because it is fast and cheap. I have a feeling fusarium wilt may take out both of these unsuitable species.

On 17.12.2017, 16:50:27, tjwalters said:

Years ago I saw a really nice queen growing wild amid the native flora in a natural area of Hugh Taylor Birch State Park.

Hi Meg and tjwalters, thanks for your report! Do you think there are already self sustaining S. romanzoffiana stands in forests in Florida? Or are most of the naturalized individuals still seedlings and dependent on cultivated individuals? I mean there must be a reason that this species is considered as a Class II invasive? Or is it more to prevent the spreading and it actually is still restricted close to settlements?

On 17.12.2017, 18:20:39, topwater said:

Is this considered good, bad, neutral, by the local biology types?

Hi topwater, it is considered as something bad by the swiss authorities, as it suppresses the regeneration of native deciduous tree seedlings by shading them out. That's at least the reason why it is on the black list of alien plants in Switzerland. But I think still more research has to be carried out in this field to asses the effects of this non-native palm in Switzerland.

On 17.12.2017, 19:18:05, CroToni said:

 

neutral I would say,their cold fronts will wipe them out,maybe in 5,maybe in 10 or maybe in 15 years,but most if not all of them will die.

they are hardy to 5f for short periods of time that place probably goes below 0 deg fahrenheit every now and then.

Hi CroToni, it rarely goes down to 15F in this area, especially near the lakes. Also days with a maximum below 32F are very rare... following they never get even closed to their absolute temperature limit. I by the way described the the whole situation regarding these palms in southern Switzerland in an article in the PALMS journal. There is also a section about the climate of this region:

https://www.freilandpalmen.ch/app/download/9171015984/Fehr&Burga_2016_Trachycarpus_fortunei_Switzerland.pdf?t=1507233317

On 17.12.2017, 20:06:32, bgl said:

Archontophoenix alexandrae palms have definitely naturalized here on the Big Island of Hawai'i. :)

2008-03-15 015.jpg

This is amazing! Thanks for sharing this photo. Islands like Hawaii are especially vulnerable regarding invasive biota because of their lack of competitors and open niches...

18 hours ago, Silas_Sancona said:

More than likely, these are W. robustra, which are planted everywhere here, but I do plan on taking a closer look at those that are along accessible spots along the river. ( I think area closest to the airport are off limits..would be my assumption anyway) Not out of the question that some filifera or hybrids might be mixed in there somewhere.

Curious if there might be some sort of pattern, ie:  maybe these scattered specimens originate from seed dispersed off palms planted near the Zoo/ Papago Park that washed down into the river, etc. Then again, being that both sp. are planted extensively all over town ( esp. Mex Fans)  its as likely that those that are planted in parks, commercial landscapes, etc closest to the River are seed sources.. interesting regardless. 

Another good Google spot to see other "renegade" groups is from where Priest dr crosses the river, just north of Rio Salado, just below Tempe Town Lake( east of this spot along the river). 

Hi Silas and Palmtreedude, nice discovery! Do you think they will get old here or will the local authorities cut them down before? How far the fertile cultivated mother plants are away from these juveniles, you think?

 

7 hours ago, hbernstein said:

In Florida, Ptychosperma elegans is on the official list. Washingtonia robusta and hybrids, Phoenix reclinata and its hybrids also pop up in unwanted places. African Oil Palm, while not that commonly planted, is also a species that is weedy and spreading locally.

I strongly recommend not planting and attempting to eliminate individuals of any of these species in southern and central parts of the state. With warming climate, they have nowhere to go but north.:(

Hi hbernstein, thanks for your response! Are they already self-sustainig, building populations with fertile individuals, or are all of these species juvenile plants close to cultivated palms? Are there any known effects of these palms on the native, invaded ecosystem?

 

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CLINODAVE

The Alexander palms naturalized in East Hawaii are such an iconic emblem of our area, in spite of their presence since only the 1920s, IIRC.  Which represents a bit of a conundrum in the debate about nonnative species.  If the Alexanders were not there, it is highly unlikely that native flora would fill the gaps;  there is too large a reservoir of aggressive nonnatives such as African tuiip, strawberry guava, fiddlewood, etc to permit any native ecosystem to regenerate in these lowland areas.  Pritchardias would be unable to reacquire any foothold because rats consume so much of the fruit that the palm is barely hanging on even in relatively undisturbed forests.  Further upslope, Alexander populations seem more reduced in number and I have seen them happily coexisting with native vegetation such as 'ohia and manele that still hold sway.  In these areas, plants such as the Azores fire tree are examples of the primary hyper-aggressive invaders.

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CLINODAVE

Regarding the Alexanders, they come from Queensland, Australia.  Queensland, and the Australasian floristic region in general, sent some of the colonizer plants of Hawaii's original floral arrivals in the past several million years.  These include Hawaii's primary forest trees 'Ohia and Koa.  So you could look at Alexanders as possibly having their arrival into Hawaii simply accelerated by a few jillion years.  Really no one can say it never would have happened.

 

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Silas_Sancona
31 minutes ago, Vinc said:

Thanks for the many replies!

Hi Meg and tjwalters, thanks for your report! Do you think there are already self sustaining S. romanzoffiana stands in forests in Florida? Or are most of the naturalized individuals still seedlings and dependent on cultivated individuals? I mean there must be a reason that this species is considered as a Class II invasive? Or is it more to prevent the spreading and it actually is still restricted close to settlements?

Hi topwater, it is considered as something bad by the swiss authorities, as it suppresses the regeneration of native deciduous tree seedlings by shading them out. That's at least the reason why it is on the black list of alien plants in Switzerland. But I think still more research has to be carried out in this field to asses the effects of this non-native palm in Switzerland.

Hi CroToni, it rarely goes down to 15F in this area, especially near the lakes. Also days with a maximum below 32F are very rare... following they never get even closed to their absolute temperature limit. I by the way described the the whole situation regarding these palms in southern Switzerland in an article in the PALMS journal. There is also a section about the climate of this region:

https://www.freilandpalmen.ch/app/download/9171015984/Fehr&Burga_2016_Trachycarpus_fortunei_Switzerland.pdf?t=1507233317

This is amazing! Thanks for sharing this photo. Islands like Hawaii are especially vulnerable regarding invasive biota because of their lack of competitors and open niches...

Hi Silas and Palmtreedude, nice discovery! Do you think they will get old here or will the local authorities cut them down before? How far the fertile cultivated mother plants are away from these juveniles, you think?

 

Hi hbernstein, thanks for your response! Are they already self-sustainig, building populations with fertile individuals, or are all of these species juvenile plants close to cultivated palms? Are there any known effects of these palms on the native, invaded ecosystem?

 

Vinc,

Regarding the example I'd posted about the Washingtonia, more than likely they originate from seed dispersed from specimens cultivated in nearby landscapes. How close? Is one of the questions I hope to look into since seed could be carried down into the river bottom during our summer Monsoon season, let alone carried some distance by various birds that indulge in the fruits off of trees nearby or several miles away. Native populations of either species occur quite a distance from here currently.

At the house, we have a large Mesquite tree where Great Tailed Grackles congregate on a daily basis. When the neighborhood Mex./ CA. Fan palms are seeding, I can barely keep up with all the seed these birds drop in the yard, beneath the tree. Left alone, they come up en-masse. 

As to how local naturalists or authorities might view those growing along the river??.. no doubt some people would look at them as invaders, that MUST be removed, much the same way they see Salt Cedar, a nasty, truly detrimental tree that has very negative impacts where it has spread. Unlike that stuff, Washingtonia is, what I would consider a regionally native species that may.. or may not have ..existed in the local environment prior to this area being settled. Surely, the Salt River itself was a much different looking environment before various things occurrd that removed the Mesquite, Cottonwood, and Willow Riparian, (or gallery, another term I've heard used to describe Riparian type habitats ) woodlands, that lined the banks some time ago. Anyone looking at satelite pictures of this area, esp. around Downtown Phoenix sees a river course that is pretty much barren. Luckily, some people are working to reverse this and restore the natural vegetation that existed before.  Hopefully these palms will be seen as benign component and allowed to grow on/ continue to naturally expand.

Taking a few moments to dive into the overall debate,  yes, there are introduced/ escapee plants which should be removed for good reason..

Here in the Desert, Salt Cedar and BuffleGrass are two of the worst. Salt Cedar has a tendency to greatly alter groundwater while BuffleGrass, a forage grass from Africa introduced several decades ago, invades Saguaro forests, which are considered native, and quickly degrades that habitat. It also makes the habitat much more susceptible to fire, which is something the Sonoran Desert did not evolve to handle well. Frequent fires= elimination/ total negative alteration of X habitat. 

California's golden hills, as most people visuaize them, are a result of several invasive annual pasture grasses brought over from Europe when Spanish explorers/ missionaries settled the state.. Natural grasslands there are ( were) dominated by perennial bunch grasses that remain somewhat green throughout the year, and have ample space for various wildflowers.  A far more diverse habitat than the straw colored hils we see now.

Range expansion, or recolonization is one thing. Imo, that definition describes X plant species re-entering regional territory it likely occpied at one time.. or, perhaps pioneering nearby territory due to a favorable growing environment. Still, it is likely that plant has a direct link to a population source to its south, west, east, etc.. in this case, native controls (  ..say insects, birds, or mammals which consume a certain %'age of the seed crop, etc) follow in tandem. No harm done, these newcommers will likely fill niches left open by other plants whose southern boundry may also be shifting.

A true invasive, as id view it, is something that is accidentally ( hopefully) introduced, but originates from a place where natural controls wouldn't also follow, thus that invader has free reign to cause trouble. Brazilian Pepper is a great example of a real ( and costly) trouble maker.

 

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Cikas
23 hours ago, TexasColdHardyPalms said:

That is a gross generalization that isnt true for much of the state. None the less those palms has 1/4" of rain, ice and then snow 24 hours prior to that low of -5f. 

Still not even close humid as some european countries. Switzerland gets 180-200 mm precipitations during winter time. Cold + humid/wet = fungus. Even if they survive such cold, rain and snow  ( that falls in palms crown ) during winter and spring months will stimulate the growth of fungus on damaged palm trees. And palms will die because of crown rot.

During winter is too cold for palms to grow, but these are perfect conditions for different fungus to grow.

This is the real reason why palms are more cold hardy in dry conditions ( less rain you have during winter and early spring better ).

-21C (-5F) in such climate would be Trachycarpus killer.

Edited by Cikas

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DoomsDave

Humans are the most aggressive invaders of all.

Had to say that.

We have a few invaders here in California: wild mustard (from Spain); tumbleweeds (from Russia, darlink!); among others.

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hbernstein
17 hours ago, Vinc said:

Thanks for the many replies!

Hi Meg and tjwalters, thanks for your report! Do you think there are already self sustaining S. romanzoffiana stands in forests in Florida? Or are most of the naturalized individuals still seedlings and dependent on cultivated individuals? I mean there must be a reason that this species is considered as a Class II invasive? Or is it more to prevent the spreading and it actually is still restricted close to settlements?

Hi topwater, it is considered as something bad by the swiss authorities, as it suppresses the regeneration of native deciduous tree seedlings by shading them out. That's at least the reason why it is on the black list of alien plants in Switzerland. But I think still more research has to be carried out in this field to asses the effects of this non-native palm in Switzerland.

Hi CroToni, it rarely goes down to 15F in this area, especially near the lakes. Also days with a maximum below 32F are very rare... following they never get even closed to their absolute temperature limit. I by the way described the the whole situation regarding these palms in southern Switzerland in an article in the PALMS journal. There is also a section about the climate of this region:

https://www.freilandpalmen.ch/app/download/9171015984/Fehr&Burga_2016_Trachycarpus_fortunei_Switzerland.pdf?t=1507233317

This is amazing! Thanks for sharing this photo. Islands like Hawaii are especially vulnerable regarding invasive biota because of their lack of competitors and open niches...

Hi Silas and Palmtreedude, nice discovery! Do you think they will get old here or will the local authorities cut them down before? How far the fertile cultivated mother plants are away from these juveniles, you think?

 

Hi hbernstein, thanks for your response! Are they already self-sustainig, building populations with fertile individuals, or are all of these species juvenile plants close to cultivated palms? Are there any known effects of these palms on the native, invaded ecosystem?

 

All the species that I've mentioned have mature, self-sustaining populations. P. elegans commonly invades natural hammock areas in South Florida. Phoenix reclinata is a pest in mangrove areas and the  hammocks behind  them.

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gtsteve

It is not a problem on a state or country wide scale, but an invasive pest on a scale that is a problem to

individuals or councils who don't pay attention to their properties, but it is the Phoenix canariensis around here. 

Due to birds, they pop up in places that are too small for them and necessitate a difficult or expensive removal.

More of a nuisance I suppose.  But the pollen from one big male Canary appears to be able to fertilize any Phoenix for miles around.

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Rd003

Here in South Fl, we have some naturalized Syagrus r. but i also would like to know: ibe started to see naturalized Phoenix sp. on the side of the road on the Florida Tpke, what are they??

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CroToni
5 minutes ago, Rd003 said:

Here in South Fl, we have some naturalized Syagrus r. but i also would like to know: ibe started to see naturalized Phoenix sp. on the side of the road on the Florida Tpke, what are they??

Hybrids,in my opinion no phoenix sp. in Florida is pure.

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PalmatierMeg

At least in my area I haven't run across "forests" of invasive queens or Washies, which may be the reason they may be Class II rather than Class I invasives. Both have been way overplanted. Queens really hate our alkaline calcareous soil and without out dutiful care and fertilization eventually die lingering deaths. In the future fusarium wilt  may take care of both palm species. However, FL has a number of non-palm non-native trees that are so invasive they destroy whole ecosystems. Queens and Washies could never compete. The worst of these is melaleuca, the paperbark tree that creates a mono forest as silent as death - no birds or other animals. Very creepy to walk through. I spent 15 years working on a State wildlife preserve to eliminate invasives like this. Melaleuca were imported to dry up swamps which at one time were believed to be the source of disease. I am highly allergic to them and they are nigh on impossible to eliminate without great effort and expense. They flower 3-4x per year here. If you cut them down and walk away, the dying tree drops its seeds and the stump sprouts new stems. If you burn it, the tree drops its seeds. At Little Pine Island we had to cut each tree down with chain saws. A group of men followed with buckets of stump killer to paint each newly cut stump. The trees were hauled to a staging area, chipped and blown into the back of tractor trailers then hauled across the county to be burned. The area had to be treated periodically to catch new growth.

Australian pines grow huge, are shallow-rooted so fall during hurricanes, spread their tiny seeds everywhere on the wind and drop their needles everywhere. Brazilian pepper grow massive, impenetrable thickets on vacant land and produce seed-laden red fruit to spread themselves. These are 3 of the worst but there are others. Invasive palms don't pose too much of an issue at the moment.

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Austinpalm

Here in Central Texas, Sabal mexicana is invading or returning depending on your point of view. Washingtonia ssp. are beginning to volunteer in certain situations locally. Farther south around San Antonio they are popping up everywhere.  Chamaedorea radicalis is naturalizing is the yards of many palm growers.  I expect it will go wild in the near future if it has not already. I would much prefer to see invasive palms versus invasive Chinese tallow, nandina, or Chinaberry.

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bubba

Hyophorbes poppin up in my yard, neighbors and behind neighbors...

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antk

Interesting discussion - for my garden here in Sydney it's the Cocos Palm (Syagrus Romanzoffiana) and the CIDP.  I have 3 CIDP growing wild in the garden and I'm contemplating how to remove them before they get too big.  My neighbor has about 20 on his property and is looking for somebody to take them off his hands.   As for the Cocos, I was unlucky enough to get a load of leaf mulch delivered and it must have contained the remnants of some of their seeds, and I've spent the last 12 months pulling out hundreds of seedlings.  They roots of the seedlings really take hold and are incredibly hard to pull up.  The stump you see in the images was a cocos that cost me over $1000 to get cut down because it looked like a telephone pole.  It always make me shake my head when I visit Southern California and I see them still being used for landscaping along roadsides in new developments.

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The Germinator

Here in my yard I have a class 2 pain in the petiole Queen palm. Between the seed litter and all the volunteers coming up I am considering decapitation as the only solution. There are 3 large queens on the chopping block. My CIDP is also a prime candidate just because I do not feel like shelling out annual trimming fees to keep it groomed. My Rhapis is also spreading like radiation. I am now working on rooting up some new shoots that emerged which were removed. They can spread if left unchecked coming up 3 to 6 feet from the original plant at times.

Has anyone ever propagated using the new shoots of a Rhapis?

 

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Laisla87

These tend to pop up everywhere here particularly on construction sites, railway tracks, disused industrial sites...

Screen Shot 2018-03-22 at 9.23.15 pm.png

Screen Shot 2018-03-22 at 9.24.46 pm.png

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rprimbs
On 12/18/2017, 10:33:21, DoomsDave said:

We don’t really have invasive palms as such here in So Cal. I guess you could say  the Washies are, sort of though they’re arguably returning natives.

On 12/19/2017, 9:38:44, DoomsDave said:

Humans are the most aggressive invaders of all.

Had to say that.

We have a few invaders here in California: wild mustard (from Spain); tumbleweeds (from Russia, darlink!); among others.

We do have CIDP's, but not so much that I would consider them 'invasive'.  I have left one on my property.  It is nice because I don't have to water it.

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