What is it? Pest of cycads Cycad Aulacaspis Scale Aulacaspis yasumatsui Family Diaspididae (armored scale)

Originally described from Thailand Found in Miami, Florida in 1996 Spreading northward in Florida into Georgia Very similar to a common scale in Florida – Magnolia white scale (Pseudaulacaspis cockerelli) Where is it from? Cycad Aulacaspis Scale

What Does it Look Like? Cycad Aulacaspis Scale Female Male Female

What Does it Look Like? Cycad Aulacaspis Scale

What Does it Look Like? Cycad Aulacaspis Scale

What Does it Look Like? Cycad Aulacaspis Scale Explosive population growth

Life cycle – 28 days Females lay more than 100 eggs Egg hatch 8-12 days Most females live approximately 1 month (as long as 75 days) Infests the plant roots Males do not feed Biology Cycad Aulacaspis Scale

Damage? Cycad Aulacaspis Scale Initially appears as chlorotic spots Fronds eventually become brown and desiccated Cycads become completely coated with a “white crust” Potential for disease development Ultimately plant death

Damage? Cycad Aulacaspis Scale

Damage? Cycad Aulacaspis Scale

What are the Host Plants? Cycad Aulacaspis Scale Cycads Preferred host is Cycas species (king and queen sago) Observed on Dioon, Encephalartos, Microcycas and Stangeria

How Do I Control It? Control is difficult Long-term, continuous effort Continuous re-infestation from crawlers from the roots Inconsistent results Introduction of natural enemies Cycad Aulacaspis Scale

How Do I Control It? Biological Control Two natural enemies were imported from Thailand and released in 1997 and 1998 Coccobius fulvus – wasp parasitoid Cybocephalus binotatus – beetle predator Cycad Aulacaspis Scale

Biological Control - Parasitoid Cycad Aulacaspis Scale Female Wasp

Biological Control - Parasitoid Cycad Aulacaspis Scale Wasp parasitizes the female scale

Cycad Aulacaspis Scale Biological Control - Parasitoid Development of the wasp inside the scale Wasp larva Wasp pupa

Biological Control - Parasitoid Cycad Aulacaspis Scale Autoparasitism One female wasp larvaTwo wasp larvae One male wasp larva

Cycad Aulacaspis Scale Biological Control - Parasitoid Well established in southern Florida Contributed to the control of this pest Still have live cycads in southern Florida Need additional control measures When possible, use low-risk pesticides On going efforts to release more parasites (regulatory agencies)

Biological Control - Predator Cycad Aulacaspis Scale Female Male

Biological Control - Predator Cycad Aulacaspis Scale

Biological Control - Predator Cycad Aulacaspis Scale

Biological Control - Predator Well established in southern Florida Probably not as good as the wasp parasitoid Need additional control measures When possible, use low-risk pesticides Cycad Aulacaspis Scale

How Do I Control It? Cultural Control Vigorous blast of water Removal of fronds Plant health Removal of plant Cycad Aulacaspis Scale

How Do I Control It? Oils and Pesticides Spray coverage is essential Repeat application Foliar and soil application Cycad Aulacaspis Scale

Horticultural oil Organocide (fish oil) Insecticides (Dimethoate, Orthene, Distance) How Do I Control It? Oils and Pesticides Cycad Aulacaspis Scale

Aulacaspis Cycad Scale Test Host plant: cycad (King Sago); 1 gal container At the onset of the test, cycad infestation among plants varied from low to high but in general was moderate. Plants were distributed so that varying infestation levels were in all treatments. Each treatment was replicated 5 times All foliar treatments were applied at 3 week intervals (0, 3, 6, 9 weeks) All drench treatments were applied on day one (no repeat application) Female scales and eggs were evaluated under a microscope; each plant was evaluated on a 1-5 scale (1 = low infestation; 5 = heavy infestation)

Mortality of Female Aulacaspis Scale

Female Aulacaspis Scale With Dead Eggs

Infestation Level of Cycad Aulacaspis Scale

How Do I Control It? 1.Monitor 2.Water wash 3.Oil spray 4.Soil and or foliar insecticide 5.Removal of fronds 6.Removal of plant Cycad Aulacaspis Scale

Catharine Mannion Research and Extension Specialist Ornamental Entomology University of Florida, IFAS Tropical Research and Education Center SW 280 th Street Homestead, FL