Asian Cycad Scale Infests Central Florida

CFPACS Asian Scale information resources

Asian scale is on the attack throughout central Florida. It has been found in Pinellas County, Tampa, Bradenton, Lakeland, Orange County, Osceola County and Brevard County.  Now with increased publicity on the west coast,  more and more people are finding they have the pest and are coming here looking for answers.  Before checking out the links below, scroll down to the lower parts of the page and examine the photographs to determine if your scale problem resembles those in the photographs. Then click on the following links below to understand how to treat and cure your sago.

Our Emergency Care and Treatment Suggestions (Simplified) 

Channel 28 Tampa News Report About Asian Scale (see video)

The Cycad Jungle Asian Scale Article by Tom Broome

The Department of Agriculture and Consumer Services

Featured Creatures from the University of Florida (IFAS)

Life History of Asian Scale in Florida by Dr Bill Howard and Avas Hamon Ph.D

 

NEW As of October  3, 2002 - Natural Predators of Asian Scale to be introduced in Tampa:

It seems the USDA is now preparing to do something to help prevent a Sago Palm extinction in Central Florida.  It seems Tampa is now considered officially to have an epidemic of Asian Scale and we will be getting some parasitic wasps from Asia that specifically eat Asian Scale. In fact these bugs are so efficient and eating most of the bugs off sagos that people in Asia do not see infestations of Asian scale as badly as we have seen here in Florida.   Hillsborough County is expected to have 5 areas targeted for release of the wasps. Currently the extension agent for Hillsborough County is trying to determine the worst infestations are located and release the wasps at these locations.   CFPACS members are assisting the Extension Service as possible and will be helping with observations as to the effectiveness of the wasps.   Here is part of the official e-mail sent to horticultural professionals recently. If you can offer some information, you are invited to participate as well.

(Letter begins below)

The number of calls I'm receiving on Asian cycad scale have been steadily increasing during the last 12-18 months. We appear to have some serious hotspots if not a minor epidemic in Hillborough County.

The ProHort website now has some information on Asian cycad scale, some links and a survey for you to fill out. Several different recommendations currently exist. A publication is in the works that will try to sort these out and present our best recommendations. That should be available and on the ProHort website this week.

Research in Miami in the late 90's identified and imported some predators / parasites of this pest that were later released and appear to have had a significant impact. As a result we have arranged to have some predatory wasps sometime in the next 2-3 weeks.

Now we need to identify the hotspots or localized areas that have a serious infestation to use for the release. In other words, we need your eyes to help locate infestations across Hillsborough County. Then we need you to fill in the online survey to help us identify the precise location of the infestation and the severity of the infestation.

The parasitic wasp releases will be based on the information you provide.

Please don't delay - when you see an infestation, make a note of the address, city and severity of the infestation. When you get a chance, go to the ProHort website ( http://prohort.ifas.ufl.edu/index.htm ). Near the bottom left corner of the homepage is a link to the Asian cycad scale page. On that page is a link to the online survey. All you do is fill in the blanks and click on the submit button. The website will automatically send me an e-mail with your information included

Dave Palmer - Extension Agent I
Professional Horticulture Services
5339 County Road 579
Seffner, Fl., 33584-3334
813-744-5519x103
813-744-5776 Fax
dkpalmer@mail.ifas.uf.edu
http://prohort.ifas.ufl.edu/index.htm

 

NEW As of January 16, 2002:

Since we first reported the situation in Tampa back in August 2001, the problem is getting worst. Reports of Asian Scale sightings are becoming common in almost central and south Florida towns. Areas just seeing the scale for the first time, just 6 months ago are now becoming so infested that its hard to find a Sago palm that is "not" covered with scale.   Extremely persistent and difficult to get rid of. Many report that if you treat the sago with pesticides consistently enough, you can rid the plant of the scale, while others are insisting the bug has the ability to armor itself away from pesticides and keep coming back because you cant completely kill them off a plant once infested.  Some will remain in armor or dormant like state and try again for life after treatment is relaxed.

This King Sago near Orlando is completely covered with Asian Scale. The leaves are becoming yellow and dried out. The attack is severe and the plant may attempt another flushing of leaves but the scale will quickly damage the new growth before they can develop. Sagos under attack like this do not survive more then 6 months under this type of insect stress.

 

Here this is the worst infected Queen Sago I have seen. This queen sago is located some 4 blocks from my home in Northdale.  The scale is present throughout the trunk system. I stopped and gave the home owner some advice in order that they may try to save a future flushing of new growth and to help control the insects. The dangerous part about a plant in this stage is that the wind will blow scales off this plant and downwind onto other sago palms. In this neighborhood, every yard has at least one sago palm.

Note above how coated white the leaf petiole is.  The little bit green along the petiole to the left side of the photo is due to my attempts to physically remove the scale from the leaves before opting to cut the leaves from the plant. These petioles were hand scraped clean of scale 3 days ago, treated with Malathion and Orthene, what you see above is how quickly the scale came up from the soil and recovered the leaf.

A different view shows somewhat more of the "pin" shaped scales on the leaves.

A close up of the leaves, perhaps showing a better view of the pin shaped crawlers on the leaves.

The white specs all over the mulch are free crawler scales that fell off the leaves as this small King Sago was stripped of its leaves to aid in control of the scale.  The scale appears to fall off easily and seem to be carried in the wind as easily as dust. Spreading by the wind is considered to be the way this scale is spread from plant to plant, neighborhood to neighborhood.. The scale is also all over the fuzzy growth areas in the crown, those were there before the leaf trimming.

A nearby King Sago and unaffected until a couple days ago. If you look carefully at the crown area you can see the scales have recently found their way to this plant and are advancing out of the crown and up the leaves.

Some recommendations from Dave Witt in treating this problem:

Unlike the native magnolia scale this Asian import will go below ground and infest the root stock. You have 2 options, pull the plant (plus the soil that immediately surrounds it) and soak the entire thing in a solution of oil/soap, then insecticide of your choice (mine w/ be to add Orthene to another oil mix); remove and destroy (burn - no landfills) the foliage first. 2nd choice w/be ground-soak the entire area in and around the root zone including the entire plant; the orthene w/be more "environmentally friendly" for this than other systemic pesticides, it'll break down quickly in the soil. The crawlers are below ground and inside the stem (any crevices/leaf bases, etc.). Removing the foliage reduces your target area and the plant should recover quicker. The scale can be wind blown to other plants, so any adjacent to any infestation should be treated accordingly. Have fun ... and stay w/ oil treatments every 2 wks for a few months afterwards, especially for any valuable stuff. It's been found recently in the top half of Brevard County, so it is moving north.

 

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