New Insect Pests of Golf Courses Wendy Gelernter PTRI
Redgum lerp psyllid Glycaspis brimblecombei
Redgum lerp psyllid Imported to CA from Australia in 1998 Prolonged infestations can kill eucalyptus Infests redgum, sugar gum, blue gum Found as far north as Yuba County Imidacloprid effective as drench or injection Biological control: Australian Psyllaephagus wasp?
Redgum lerp psyllid adult and eggs
Redgum lerp psyllid eggs
Redgum lerp psyllid nymph
Redgum lerp psyllid nymph
Giant Whitefly, Aleurodicus dugesii Imported from Central America: TX (1991), CA (1992), LA and FL (1996) 1st CA identification in San Diego (1992); now throughout Southern CA and parts of AZ Attacks more than 43 different ornamental plant groups: hibiscus, bird of paradise, canna, banana, begonia, avocado, xylosma, etc.
Adults are 3 times larger than other U.S. whiteflies (3/16 ) (66)
Wax spirals are deposited by adults as they walk or lay eggs on leaves
Nymphs (wingless immatures) produce hair-like wax filaments up to 2 long
Giant whitefly damage and control Leaf drop, plant death due to sap feeding Sooty mold causes cosmetic damage; if severe can decrease photosynthesis Syringe infested leaves (especially undersides) once a week Imidacloprid as a spray or drench Biological control?
RIFA worker: Red-brown, 1/8-1/4 long, clubbed antennae, thin waist, aggressive Photo: Texas A&M
Pustules and blisters from fire ant stings (photo: Texas A&M)
Red imported fire ant (RIFA) Introduced to U.S. in 1930s from Brazil First detected in Orange County, CA nursery shipments in 1998 Flourish in areas where minimum temps are >10F and rainfall is > 10 per year (or irrigation is present) Hazard to human health, livestock, crops, electrical equipment Beneficial in sugar cane, other crops
Mounds are supposedly characteristic for RIFA Conical, dome shape of soft soil with crusty surface Native fire ants construct irregularly shaped mounds consisting of loose, scattered soil >100,000 worker and winged ants per mound Photo: Texas A&M
The internet is your friend (???) Mounds are an identifying feature for RIFA Colorado State University: 10-24 wide X 18 high University of Minnesota: 16 wide X 10 high University of California: 18-24 wide X 6 high University of Florida: 36 wide X 18 high Nests may also be built without mound -- in areas with sufficient moisture and food (logs, building walls) Mowing flattens mounds A new colony does not make mounds for several months
Red imported fire ant quarantine in California Orange County quarantine established February, 1999 Parts of Riverside and Los Angeles County also quarantined Restricts transport of soil, plants and sod with soil or roots attached, hay and straw No major regulatory impact on golf courses YET Occurrence in San Diego, Fresno, Kern counties may result in further quarantines
RIFA control in California Eradication is the goal in Orange, LA and Riverside counties Broadcast baits of slow-acting insecticides that target queens & reproductives Amdro (hydramethylnon) Distance (pyriproxyfen) Award (fenoxycarb) Chipco Choice (fipronil)*** not registered in CA*** Individual mound treatments with fast-acting insecticides to relieve nuisance worker ants Orthene, Sevin, Diazinon, Dursban
This year, we confirmed a serious BTA grub infestation in San Diego County on May 16 6 weeks early!
Black turfgrass ataenius damage to cool season turf
Black turfgrass ataenius Ataenius spretulus
Normally, adult BTA activity begins in mid- to late June. Grub activity begins in late June/early July Callaway Golf. Carlsbad, CA. 1996 # BTA adults/week 1400 1200 1000 800 600 400 200 0 4/30 5/14 5/28 6/11 6/25 7/9 7/23 8/6 8/20 9/3 9/17 10/1 10/15
Minimum soil temperature Number of days 60F or above. San Diego, CA (CIMIS 66) 80 60 40 1998 1999 2000 20 0 Mar April May
Minimum soil temperature Number of days 60F or above. San Diego, CA (CIMIS 66) 80 60 40 1998 1999 2000 20 0 Mar April May More than 35 days of minimum soil temps 60F or above
Oleander leaf scorch Drought stress/salt burn symptoms: stunted, yellowed leaves, tip burn, defoliation, die-back of twigs and branches Kills oleander about 2 years after 1st symptoms observed Cal Trans predicts $52M in losses along 2100 miles of California highways
Oleander leaf scorch Caused by the bacterium, Xylella fastidiosa which was isolated in CA in early 1990 s; now in southern CA, AZ TX Related strains of Xylella cause Pierce s disease of grapes, and other serious diseases in almond, oak, peach and plum Water movement is blocked through bacterial growth and production of gellike material in xylem
Oleander leaf scorch management No known cure for the bacterial disease Management targeted at plant: 1) remove diseased plants 2) avoid potentially susceptible replacement plants such as crape myrtle, sumac, eucalyptus, coast live oaks, periwinkle, euonymus, redbud, ash, privet
Glassy winged sharpshooter Homalodisca coagulata
Oleander leaf scorch management Transmitted by sharpshooter insects (glassy winged sharpshooter, smoke tree sharpshooter, others?) Insects cannot be eradicated It may be possible to protect plants through applications of systemic insecticides (imidacloprid)