cycas debaoensis infestation or normal stem tomentosa

[GDLWyverex]

My cycas debaoensis's first flush since I acquired it has fuzzy white stems, and I can't decide  if this is normal or some infestation. I have hit it twice with a systemic pesticide which does not seem to have made any difference.

Any feed back is greatly appreciated

 

Richard

[Merlyn]

That is a severe infestation of Asian Cycad Scale, and it will kill that Deb and spread to your other Cycas if you don't treat it.  Here's what I have done to clear it off of my collection:

• Spray off the plant with strong hose pressure (not a pressure washer) using a normal hose nozzle.  The best way is to hold a frond with one hand and spray it off with the other.  This dislodges the adults that are immobile, they'll then die.  Don't wash them towards other Cycas, you'll just spread the immature ones.  If you have a lot of Cycas in the area, maybe skip this step.  Make sure you spray off the underside of the leaflets, that's where the ACS love to attach themselves.
• Do a soil drench around each infested plant with Dinotefuran.  Don't waste your time or $ with any other systemic, ones like Imadicloprid are not effective against scale.
• Spray the leaves every other week with a good concentration of Acephate (Orthene) or Malathion.  These are effective against the "crawlers" that will try to reinfest after you sprayed off the hard-shelled adults.  Acephate is mildly systemic, so a soil drench *might* help a bit.
• Put used coffee grounds around the base of each plant, but not in the crown.  Caffeine is systemic sort of like the neo-nicotinoids like Dinotefuran, so it's a cheap low-level insecticide that'll help long-term.  It won't cure a big infestation, but it'll help at the same time it helps as a fertilizer mulch.
• If you have a bunch of nearby Cycas then do a soil drench of Dinotefuran on them too.  This will help kill off any crawlers that go in that direction.

Good luck with the above, the cycad scale has killed of hundreds of thousands of Cycas Revoluta in FL.  I got it on a bunch of mine from my neighbor's snow-like plants, and managed to clean it off of about 20 Cycas Revoluta using the above method.  That worked last fall, and only a few weeks ago I found that 3 were reinfested.  I only lost 1 plant to the stuff, and it was a 4' trunk one that my neighbors dug up and threw to the curb.

For sources, I bought Malathion at the local Home Depot as a liquid concentrate, Acephate (Orthene) from Amazon in granules.  I bought Alpine WSG 500g Dinotefuran granules from eBay.

[GDLWyverex]

Thanks so much for the great info. I have done the systemic and spray routine and during the spray I noted that most of the white actually fell off which makes me think that my previous attacks upon it with Furadan and Diazanon were not in vain.

Thanks

 

Richard

[Merlyn]

Diazinon is a good foliar spray too, it's banned in the US for residential use.  It's about equivalent to Malathion and would be a good surface killer for the "crawler" young stage.  Furadan is carbofuran and is a systemic carbamate insecticide.  It's similar to Acephate, which is mildly systemic in plants.  Those two combined with spraying off the adults might get rid of your infestation. 

The key is a good systemic, because once the adults form a hard shell they are pretty much invulverable to foliar spray insecticides.  You can't get them all by spraying off the adults, which are immobile after they latch into place.  But you can break the life cycle by hosing off as many adults as possible and then foliar spraying to kill the babies.  They can live in soil and in the roots of the plant too, so a soil drench of Furadan would probably kill off any in the soil nearby.

[TexasColdHardyPalms]

WOW, that is a nasty scale infestation...

[joe_OC]

Try simple green at a 15:1 ratio for scales.   I put simple green in hose end mixer and soak them.  Works great on lots of different insects.  

[cycadjungle]

Scrape some of those off with your figure nail. Check to see if underneath they are bright yellow or a dull color. They may be dead from your systemic snd hàvent been knocked off. You might be able to wash most of those with a little pressure and hose.

 I'd make mud out of the used coffee grounds and cover the root area and on those stems.

[Brian]

Wow Richard that looks bad. You can use a soap spray to kill it and then spray it off. I use dish soap from Costco for my soap spray. This seems to work way better then any insecticides. Dont be afraid to remove the plant and wash everything including the roots and then replant in clean soil. Ive doen this countless times with good success. 

[GDLWyverex]

21 hours ago, Brian said:

Wow Richard that looks bad. You can use a soap spray to kill it and then spray it off. I use dish soap from Costco for my soap spray. This seems to work way better then any insecticides. Dont be afraid to remove the plant and wash everything including the roots and then replant in clean soil. Ive doen this countless times with good success. 

How strong a solution do you mix?

 

Rivhard

[Brian]

1 hour ago, GDLWyverex said:

How strong a solution do you mix?

 

Rivhard

Just add liquid dish soap until the water feels soapy. You dont have to add that much. That soapy slime suffercates the plaga. I apply it with one of thoses 20 litter back pack type pump sprayers. Sometimes with smaller cycads that are heavily infested like yours, I remove the plant from pot, wash off all soil and soak it for a few minutes in the soapy mix. Cycads are tough and can survive several days without replanting however they can die quickly from the plaga so don't hesitaes to remove it asap. 

 

Edited September 2, 2019 by Brian

[GDLWyverex]

19 hours ago, Brian said:

Just add liquid dish soap until the water feels soapy. You dont have to add that much. That soapy slime suffercates the plaga. I apply it with one of thoses 20 litter back pack type pump sprayers. Sometimes with smaller cycads that are heavily infested like yours, I remove the plant from pot, wash off all soil and soak it for a few minutes in the soapy mix. Cycads are tough and can survive several days without replanting however they can die quickly from the plaga so don't hesitaes to remove it asap. 

 

I'll give it a try. How long after applying should I wait to spray off the corpses??? It is a bit large to unearth and soak (about 15" in diameters, mostly below ground level) so Iĺl spray with similar equipment as you described

Thanks

 

Richard

[Brian]

On 9/2/2019 at 5:19 PM, GDLWyverex said:

How long after applying should I wait to spray off the corpses???

I would wait atlease until it dries if spraying while in the ground however when i have cycads infested like the one you posted, I find that the plaga is also on the primary roots. If you dont remove it from the roots it will continue to kill the plant. By far the easiest way to address this for me has been to remove the plant and wash off all the plaga. Once done, plant it in fresh mix and a clean pot. They recover surprisingly quick and are never too big to remove if needed.