Cycad Scale

[gsytch]

My only Cycas revoluta has the dreaded white asian scale/mealybug stuff. It is about 3-4' tall and artistically planted under a P. sylvestris. I guess I was too busy to notice and then BAM! it is all over the base and some leaves.

I have tried Rose Systemic (imida...something) Malathion and Triox. None appears to make much of a difference. I have a Cycas tainguenisis (or close spelling) which is now showing it.

What is the best method, other than removal, to get rid of this? Help! Thanks Greg in rainy sweaty New Port Richey FL

[palmislandRandy]

I don't see these around much anymore, due to the scale. There were a few remedies around, one being used coffee grounds packed around the base. I believe the coffee grounds (free at Starbucks) somewhat disrupts the life cycle of the scale. Horticulture oils or soap spray will smother the scale, but require frequent applications. Anyone have any other remedies?

[redant]

Organocide does work http://www.homedepot.com/buy/outdoors/garden-center/organic-labs/64-oz-readytouse-organocide-80271.html but as rabdy states, requires frequent applications. I don't bother with this cycad anymore as it's just to much of a pain to control the scale. Obviously most of FL feels the same way as you don't see them much anymore.

[gsytch]

I know. I only have two, and one is a taller type. The other is the usual Sago. I will try Organocide, cant hurt. Thanks! I will try the oils once it cools.

[Kailua_Krish]

Is this disease worse on certain species of Cycas than others? I've been hesitant to plant any within this genus and instead have been relying on Dioon and Ceratozamia.

-Krishna

[Moose]

Is this disease worse on certain species of Cycas than others? I've been hesitant to plant any within this genus and instead have been relying on Dioon and Ceratozamia.

-Krishna

Good decision. The asian scale goes below ground and even covers the underground parts of many Cycas I've heard.

[George Sparkman]

I am with Moose on this.

Ceratozamias & Dioons are perfect for Miami.

[Dave-Vero]

Tom Broome's coffee ground remedy should work. The scale does indeed infest roots.

There's gobs of excellent cycads for Florida. Today, I'm kind of proud of a spiny Encephalartos hildebrandtii, which is putting out its second flush of the year, while a cute little Lepidozamia peroffskyana from eastern Australia is looking happy. A cycad flyer from Leu Gardens in Orlando calls Lepidozamia one of the best cycads for central Florida, partly because it has soft, friendly leaves.

Leu brochure (pdf)

[Really full garden]

I have been fighting this for a few years now .I feel I have won a few battles ,but the war still rages on.I find my C.revoluta seems to be the easiest to treat and remain scale free longer.My C. rumphii are always infested .My C.angulata has remained scale free despite being just meters from a constantly infected clump of C.rumphii.

[cycadjungle]

The reason the grounds as a mulch works is that the alkaloids in the coffee leach down into the soil and directly kill the insects on the roots. What I tell people to do is use the used coffee grounds as a mulch and then use a "sun tea" made out of coffee grounds as a direct contact spray to kill what is on the plants at that time. usually, you only have to use the spray about twice a year to keep the plants clean. Here is a copy of my article if you haven't read it already:

http://www.cycad.org/documents/Broome-Coffee-2007.pdf

I don't really want to tell you to use this, but if all else fails, and you want to use something that is a bit more harsh, Orthene will nuke just about anything, including yourself if it gets on you, but that certainly will knock off any scale that gets on your plants. Just like the oils, you only want to use it first thing in the morning because if you use it at noon time, you will torch your plants pretty well. Using the oil on the plants and used coffee grounds as a mulch will aslo keep everything in check.

As far as other cycads go, landscape designers are using Dioon edule to replace revolutas. They have the same basic 6 foot wide size and are even more cold hardy than revolutas. They also don't get the scale.

As far as other cycas species go, all will get the scale, but they don't get on some as much as others, at least healthy ones anyway. Any weak plant in the cycas genus will get scale all over it, so keeping them well fertilized helps keep them clean. Another aspect, the queen sagos seemed to die out first in Miami and the revolutas seemed to take longer. I have noticed that the vascular system of the rumphiis doesn't seem to translocate the chemicals as fast as the revolutas. some cycas species grow much faster than others. Cycas deboaensis grows super fast, and can even have female cones coming out after 3 years from seed, where female revolutas usually take about 10 years to show their cones. When I performed my experiments with the coffee, I used debaoensis plants in many cases for my test plants. I did this becasue I knew, if for some reason the scale got out of hand, I could bring those plants back much easier than with something like a rumphii type. Luckily, everything went very smoothly and I have not had any problems with the scale reoccuring on any plants. So, for anyone wanting to try other cycas species, I say plant a debaoensis. For anyone who says cycads grow slowly, try one of these. Give them good root room, good fertilizer, lots of water, and maybe under some tree cover and you will see a 3 year old plant from seed putting out 10 foot long leaves.

Greg, you need to take the 55 mile drive and come down to north Lakeland sometime and check out all the other cycads you can grow around here that don't get Asian scale. Tom

[Jerry@TreeZoo]

In the Arboretum, we had a small revoluta and Queen Sago with 5'-6' of trunk. The scale killed the revoluta years ago, but not the Queen. Over the years the infestation seemed to be less and less on the Queen and I stopped treating it with imidicloprid. I am sure there are still a few scale on it now but it is not bad enough to treat it. I think the natural predators are taking care of it.

[Really full garden]

I am about to try a dog flea and tick collar on a couple of my moderatly infested C.rumphiis.I will use the coffee grounds at the base as well.

[virtualpalm]

Scott, I think you are more than likely wasting your money on the collar, but let us know if it works.

Jody

[rozpalm]

I've had pretty good luck with Dinotefuran (Safari 20SG) as a soil drench.