ABSTRACT Too Little and Too Late???? Asian Scale (ACS) Chronology Asian cycad scale (ACS), yasumatsui, was 1972 – described in first detected in Tumon, in December 2003 in front introduced against Asian 1996 – ACS detected in Florida of a hotel where revoluta, an introduced ornamental 1998 – ACS detected in Hawaii cycad and , an indigenous cycad were cycad scale, Aulacaspis yasumatsui, on Guam 2003 – ACS detected on used for landscaping in Guam’s planted. The scale is believed to have been imported from Tumon Bay hotel district Hawaii in 1998 on ornamental cycads. The scale currently R.H. Miller1, A. Moore1, R.N. Muniappan1, A.P. Brooke2 and T.E. Marler1. 2004 – ACS spreads to and C. micronesica infests introduced and indigenous cycads on about two 1CNAS-AES, University of Guam, Mangilao, Guam (fadang) throughout Guam thirds of Guam’s 354 square kilometers. Severe 2Guam National Wildlife Refuge, Dededo, Guam 2005 – Ryzobius lophanthae and Coccobius fulvus released on infestations have been observed to kill both species within Guam; Plans made to preserve C. micronesica germplasm from a few months. We fear that C. micronesica may be Guam on the nearby island of Tinian threatened with extinction should the scale spread to the few other Micronesian islands that harbor it. Rhyzobius lophanthae, a coccinellid introduced to Asian Cycad Scale Management Hawaii in 1894 for other scale , was imported from Biological Control Agents on Guam Maui to Guam in November 2004 and released on C. Rhyzobius lophanthae micronesica at the Guam National Wildlife Refuge at • Introduced in Hawaii in 1894; Guam ??? 1930s Ritidian point in February 2005. R. lophanthae populations • Adults collected on Maui Nov. 2004 by Hawaiian have subsequently spread to other C. micronesica, and Department of Agriculture additional releases have been made throughout the island. • Laboratory colonies established at UOG However, R. lophanthae alone will not likely contain the • Released at Ritidian Point on northern Guam in infestation. February 2005 A Chinese strain of Coccobius fulvus, a hymenopteran • Redistribution on Guam – April 2005 - present parasitoid originating in Thailand and China, has recently Coccobius fulvus been imported from Florida. Funds are being sought for Chinese strain from Florida released on Guam July exploration for additional biocontrol agents in Asia. IPM 2005 strategies using systemic insecticides applied to pruned cycad boles are also being developed. Cultural Control Replace cycads with less susceptible (avoid Cycas, , , and ) Chemical Control Foliar spray with oil growth regulators & neonicotinoids Systemic insecticides

Cycas micronesica is endemic to the and is the most common tree species (DBH > 10 cm) Regulation of Movement of Cycads among on Guam with 1.5 million trees. All are at risk. Islands Within Cooperation with 2003 2005 USDA-APHIS, ARS Secretariat of the Pacific Community (SPC) and Micronesian Island PPQ Departments in Guam Republic of Republic of the Marshall Islands Before Asian cycad scale arrived, cycads were the perfect low maintenance plants for Guam, being typhoon Federated States of Micronesia resistant and drought tolerant. Cycads are now high maintenance plants. Mortality of heavily infested, untreated Commonwealth of the Northern Marianas Cycas revoluta and Cycas micronesica (shown above) is 100%.

Male and female ACS cover the underside of Cycas revoluta becomes increasingly stunted Rhyzobius lophanthae, a coccinellid obtained from Maui, Hawaii has been mass reared, released Release sites for Rhyzobius and reproductive organs of Cycas micronesica, with each regrowth of leaves and usually dies and redistributed throughout Guam. Predation rates approach 100% on some infested plants as lophanthae on Guam. locally know as “fadang.” within one year if left untreated. monitored by counts of destroyed scales.