Washingtonia ROBUSTA or FILIFERA ?

[greekpalm]

I thought i was sure what it was but somebody gave me second thoughts .....

i hope those pictures help... if not tell me what part of the palm I have to take pictures of !

[iamjv]

Looks like filibusta to me....

[sonoranfans]

Looks like a filibusta hybrid. A pure filifera doesnt have the orange/brown leafbases, and a pure robusta wont have a trunk as thick as that one.

[Kostas]

I totally agree with what has been said. Certainly not a pure W. filifera but seems too thick for a pure W. robusta as well... So W. filibusta...

Btw and most importantly,this palm has been attacked by Rhynchophorus or Pysandisia as its obvious in the leaf base picture!!! I have never seen a dead Washingtonia from this but i do have seen one with a necrotic spear that seemed infected. In any case,you should treat this palm if you want it. And given your locality and the huge populations of Rhynchophorus around your area,you really should be applying preventive treatment to any palm you have...Pyrgos Phoenix sp. palms are now numbered in one hand...Just 1-2 more years and i bet there will be none left in Pyrgos and the surrounding areas...

For me,nematodes with Biorend R have worked great in protecting my palms in Pyrgos and they are non-toxic and environmentally friendly. I even saw 2 rows of holes on one of my Trachycarpus leafs,characteristic for Rhynchophorus and Paysandisia early stage damage and then no more which means they got killed from my following application of nematodes

[greekpalm]

s'euxaristo Kosta

i know about the attack (most probably Pysandisia). I've been treating them from last September. Do note that from what i've heared Pysandisia seems to be resistant to the nematodes you were referring to! I also know that my palms suffer from magnesium and potassium. Thank you for your concern !

My last question is how THICK do Filibusta get ? and how can i control their thickness ? (if there is any way to do that)

[Kostas]

I dont know which borer has attacked your palm although Rhynchophorus may be more likely due to its greater number in the area and also because it favors warm areas while Paysandisia prefers cooler ones. None however seems to be restricted to their favorite places and it does has been reported in Southern Athens as well. Anyway,i dont remember if i have read any test studies of the nematodes concerning Paysandisia archon control,but i know they write they are effective on it as well,at least the ones used in conjunction with Biorend R(this is just a Chitosan solution that protect the nematodes from dehydration and protects them from UV,both of which kill the majority of them otherwise). Steinernaria carpocapsae nematodes are not species specific,just borer insect specific as they dwell the tunnels or stalk for passing larvae or adults. When a larvae or an adult crosses,they get inside it from the respiratory pores,feed,breed and kill it fast! So there is no reason to expect Paysandisia to be immune or resistant to them!

Its good to hear you know about the attack and are treating it!

Magnesium deficiency is very common in palms living in Athens and not something to worry about too much. It seldom gets to a worrying degree but palms surely look better when their owners fertilize correctly and fix it

You may want to check you soil ph and salt content. A soil analyses would be very helpful to determine the causes of the deficiencies and the best way to deal with them on the long run

I dont think you can control the thickness of your Washingtonia in any goo and lasting way. If you treat it real bad,chop roots,not water at all and do lots of cultural mistakes,you may keep it thinner as long as you continue to do such things. Once it finds good growing conditions again,it will swell its trunk fast but not always in a beautiful manner,as it would do if cultivated properly(cranks on trunk,etc). Still,they are pretty resilient though!

I think the best way to have a thin trunk Washingtonia is to sell this ones and get a proper W. robusta Your multiple planting is gonna get quite large in diameter when all of them expand their trunks!

[sonoranfans]

s'euxaristo Kosta

i know about the attack (most probably Pysandisia). I've been treating them from last September. Do note that from what i've heared Pysandisia seems to be resistant to the nematodes you were referring to! I also know that my palms suffer from magnesium and potassium. Thank you for your concern !

My last question is how THICK do Filibusta get ? and how can i control their thickness ? (if there is any way to do that)

I dont know how you can control the thickness of a filabusta, but I have seen them with 2' thick trunks sans leaf bases. Pure filiferas can have trunks up to 4' thick. Robustas are typically around 1' thick. The leafbases of a pure filifera will be grey and the fronds a light grey green. Your palm is too green to be pure filifera, but no way that thickness trunk is pure robusta. The filibusta will do notably better than a pure filifera in a wet winter climate.

Edited February 9, 2011 by sonoranfans

[greekpalm]

Those are more specific pictures, probably you are right but just to be sure i updated this thread with new pictures.

hope you guys still have the same opinion.