Master Gardeners: Two oriental fruit flies found in Redding
Q: The County Ag Department has hung oriental fruit fly traps in my fruit trees. Can you tell me why they are trapping this fly and how the oriental fruit fly got here?
A: The Shasta County Agriculture department found two oriental fruit flies in the
Redding area last month. This is a major concern because of all the agricultural crops produced in California and especially the fruit and nut orchards that we have locally. According to the U.S. Department of Agriculture, the oriental fruit fly can infest 478 different fruit and vegetable crops and is very destructive to the crop. Two flies don’t sound like much, but the average oriental fruit fly can produce somewhere between 1,200 and 1,500 eggs within their life time and the life cycle of the fly is about 10 days from egg to reproduction. So in about two weeks those two flies have the potential of producing over one million oriental fruit fly offspring and each of those can produce another million and so on. The best guess as to how the oriental fruit fly arrived here in Shasta County is that someone brought in or received a shipment of backyard fruit from another country that was infested with the fly larva.
This is a good reminder that as we are traveling for the holidays not to bring back citrus or other fruit from the yards of friends or relatives from other parts of the state, no matter how tempting. The oriental fruit fly is not the only problem. Two other invasive pests that we would like to keep out of our area are the brown marmorated stink bug (BMSB) and the Asian citrus psyllid (ACP).
The brown marmorated stink bug has become a pest in Sacramento, Chico, and areas of Southern California and is excellent at ‘hitching rides’ on cars. It is about 5/8” long, marbled brown, with two white stripes on the antennae and rough shoulders. It’s a voracious eater and will consume landscape plantings as well as vegetables and fruit trees — including the fruit and leaves. It frequently clusters in large groups on tree trunks, patios, or vegetable rows and loves to over winter inside the home. If you see any bugs you suspect might be BMSBs, place one in a sealable plastic container and bring it to the Master Gardener office for identification and assistance in how to deal with it as pesticides are ineffective. For more information see https://bit.ly/2DeXGC4.
The Asian citrus psyllid (ACP) is the second insect to be on the lookout for as we do not want this one to spread into our area. This pest was first detected in Florida in 1978 and within 10 years had spread to 9 other citrus growing states. The ACP are the size of an aphid and mottled brown with red eyes. It feeds on all citrus from oranges to lemons and limes and some other closely related ornamentals. As the nymphs feed on new, soft leaf growth they excrete a ‘honeydew’ that looks like whitish, waxy, curly strands. The Asian citrus psyllid can carry a disease called huanglongbing (HLB) caused by bacteria. There is no cure for HLB at this time, and a tree infected with this disease will die within five years. Early signs are trees with loss of new leaves, twisted new twigs and bitter lopsided fruit. HLB disease has spread to nearly all of the commercial citrus orchards in Florida, devastating the industry and has been found in Southern California as far north as Bakersfield in backyards.
If you have citrus trees, inspect the new growth regularly and if you spot ACP, contact our Master Gardener office or the CDFA Exotic Pest Hotline 800-491-1899. For more info see https://bit.ly/2Df8Kzb.
The Shasta Master Gardeners Program can be reached by phone at 242-2219 or email mastergardener@shastacollege.edu. The gardener office is staffed by volunteers trained by the University of California to answer gardeners' questions using information based on scientific research.