Posts Tagged: fruit
Staying Up to Date on Fruit Flies
Invasive Fruit Flies
California is currently experiencing an unusually high?number?of invasive fruit fly?detections, resulting in quarantines being established across numerous California counties, including Ventura County. These invasive fruit fly species – including Mediterranean fruit fly, Oriental fruit fly, Queensland fruit fly and tau fruit fly – are considered not established in California. The California Department of Food and Agriculture (CDFA), in cooperation with the United States Department of Agriculture (USDA) and various County Agricultural Commissioners, has initiated local regulatory measures to eradicate and prevent the further spread of these fruit fly species statewide.
Resources:
- CAFruitFly.com
- Invasive Fruit Fly - Guide for Growers [NEW]
- Fruit Fly Quarantine Boundaries and Maps
- Frequently Asked Questions from Industry Members
- Harvest and Crop Movement Requirements for Growers
- Oriental Fruit Fly (Over 300 crops impacted)
- Mediterranean Fruit Fly
- Queensland Fruit Fly
- Tau Fruit Fly
- Residential Treatment Information and Maps (Conducted by CDFA)
While CDFA, USDA and our local County Agricultural Commissioners will be working to educate residents on the issue in the various quarantine areas, we ask you to please encourage nearby residents to avoid moving any homegrown produce from their properties and to cooperate with agriculture officials working in their area.
CDFA Photo: Oriental Fruit Flies
oriental fruit fly five sisters
Praise the Rain, Pass the Fungicide
Although, it's probably too late for the fungicide to correct Citrus Brown Rot
and Septoria on coastal lemons.
In normal rainfall years, a skirt spray of copper is done to prevent rain splash bringing spores of various Phytophthora species in contact with fruit. The spray is done the fall especially if high rainfall is expected that year, and can be reapplied in January/February if indeed rain has arrived. The spray is usually only up about 4 feet from the ground, rarely needed above that. But this year, there has been lots of wind and brown rot has appeared throughout tree. There has been lots of wind to spread the spores and create disease in fruit quite above ground level. Fruit on these trees is going to need to be selectively picked to avoid the infected fruit, adding to harvest costs.
https://ipm.ucanr.edu/agriculture/citrus/brown-rot/
Septoria is less common than brown rot along the coast where a skirt spray is or used to be normal practice. This was before the drought and low lemon prices made the practice less common. In the case of septoria, a whole tree copper spray is recommended in the fall. The disease, although not unseen, is not common, so most growers would apply only a copper skirt spray for brown rot. With this 2023/2024 rain year, the disease has showed up in many orchards, and of course, it is above the brown rot spray line in the canopy.
https://ipm.ucanr.edu/agriculture/citrus/septoria-spot/
Both of these diseases are going to cause problems for growers, because once in the fruit, it's not treatable or salable.
POM ology
POM - Greek for "apples", but more generally "fruit"
ology - the study of
So pomology is the study of fruit trees. And how to describe them becomes important and pictures have been an important way of describing fruit. Worth a thousand words.
In 1886, a US agency set out to record new fruit varieties. The results are wondrous. Watch the story HERE
As agriculture in the United States transformed from domestic and local to industrial and national, in 1886 the US Department of Agriculture (USDA) embarked on an ambitious project. To help fruit cultivators protect and profit from their innovations, the agency hired illustrators to recreate images of newly developed varieties of fruits and nuts, capturing the colours, textures and shapes of each in intricate detail. By the programme's end in 1942, more than 7,500 unique, and often beautiful, images had been produced. In his short film, the Toronto-based filmmaker Sebastian Ko provides lively flipbook tour through the USDA ‘Pomological Watercolor Collection' to explore its history and legacy. In particular, Ko focuses on the contributions of some of the talented female artists who helped bring the collection to life at a time when very few jobs were available to women.
And see the pictures here: https://search.nal.usda.gov/discovery/collectionDiscovery?vid=01NAL_INST:MAIN&collectionId=81279629860007426
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Fruit Flies
Invasive Fruit Fly Quarantine
What to know as a SJV citrus grower?
Sandipa Gautam
Area Citrus IPM Advisor
UC Statewide IPM Program Operations
Several species of invasive fruit flies that belong to the family Tephritidae are considered serious pests of hundreds of agricultural crops including citrus. These flies lay eggs on or near the fruit surface, and when the maggots hatch, they bore into the fruit, making it unfit for human consumption and causing major losses to fruits and vegetable production. California is experiencing an unusually high number of invasive fruit fly detections in the 2023/24 season and several areas in California are now under a fruit fly quarantine. For many invasive fruit fly species, quarantine is triggered when two or more adult flies are caught in a trap or by a single detection of larvae or pupae indicating a breeding population. Core area is 0.5-mile radius around the detection site and a quarantine area is 4.5-mile radius around each detection.
Counties Currently Impacted by Invasive Fruit Fly Quarantines:
- Oriental fruit fly: Contra Costa, Riverside, Sacramento, San Bernardino, and Santa Clara Counties (Figure 1)
- Mediterranean fruit fly: Los Angeles County (Figure 2)
- Tau fruit fly: Los Angeles County (Figure 3)
- Queensland fruit fly: Los Angeles and Ventura Counties (Figure 4)
Why is fruit fly quarantine concerning to citrus growers?
Citrus is a known host to all invasive fruit fly species. Fruit fly life cycle begins as eggs laid by adult female on surface or under the fruit rind maggots hatch and bore into the fruit and develop inside the fruit (Figure 5). They drop to the ground and pupate. Many fruit fly species are known to overwinter as prepupae or pupae, but some species like Medfly can overwinter in all life stages inside fruit or as pupae on the ground. Adults emerge in early spring and the life cycle continues. Because eggs and immatures can be present inside the fruit, movement of infested fruit may accidentally transport them to a new area where fruit fly has not been detected.
Invasive fruit flies – what to look for?
Four species of fruit flies are currently regulated in California. The adults may look similar to houseflies but are distinctly different in color and the markings on the body. They are about 5-8 mm in size, much bigger than spotted wing drosophila, another invasive species that has been established in California.
- Oriental fruit fly: ~8 mm size, bright yellow colored body with a dark T shaped mark on the abdomen (Figure 1).
- Mediterranean fruit fly (Medfly): ~5-6 mm in size, yellow-light brown body, clear wings with brown bands (Figure 2)
- Tau fruit fly: ~7 mm in size, yellow body with black markings (Figure 3)
- Queensland fruit fly: ~5-8 mm in size, wasp-like body, reddish brown in color with distinct yellow markings, clear wings with band along the top margin.
Figure 1. Oriental fruit fly adult with identifying characters (left) and areas in California under quarantine as of January 2024: Contra Costa, Riverside, Sacramento, San Bernardino, and Santa Clara Counties (right).
Figure 2. Mediterranean fruit fly adult with identifying characters (left) and areas in California under quarantine as of January 2024 – Los Angeles County (right).
Figure 3. Tau fruit fly adult with identifying characters (left) and areas in California under quarantine as of January 2024: Los Angeles County (right).
Figure 4. Queensland fruit fly adult with identifying characters (left) and areas in California under quarantine as of January 2024: Ventura County (right).
You can find more information about invasive fruit fly species including interactive quarantine maps, regulatory information and pest profile information below: https://www.cdfa.ca.gov/plant/PDEP/treatment/index.html
Figure 5. Fruit fly larvae are white, legless maggots. They bore into the fruit and feed on pulp. Infested fruit may drop and decay.
What is happening to prevent fruit fly spread?
The California Department of Food and Agriculture (CDFA), in cooperation with the United States Department of Agriculture (USDA) and County Agricultural Commissioners, has initiated local regulatory measures to eradicate and prevent the statewide spread of Queensland fruit fly, Tau fruit fly, Mediterranean fruit fly and Oriental fruit fly. California Citrus Quality Council (CCQC) in coordination with researchers is developing a systems approach that allows for post-harvest treatment of citrus fruit for movement from the core to pack.
What can you do?
- If you are a grower inside the quarantine area, follow regulations about harvesting, processing, or storing fruit. Contact your County Ag Commissioner about the latest regulations, or review FAQs here: https://www.cdfa.ca.gov/plant/fruitfly/docs/Invasive_Fruit_Fly_FAQ_Industry_1-18-24.pdf . If your property is under fruit fly quarantine, follow either pre or postharvest treatment protocols from USDA to move fresh fruit
- Grower outside the quarantine area, stay informed, invest in trapping and pre-quarantine treatments to avoid potential harvest delays should a quarantine be established in the future. For information on prevention and exclusion visit: https://www.cdfa.ca.gov/plant/PE/InteriorExclusion/current_preharvest_treatment.html
- Quarantines boundaries can change rapidly, so it is critical to stay in communication with your local agricultural commissioner.
- Report any suspected invasive fruit fly sightings to CDFA, USDA or your local County Agricultural Commissioner.
- Encourage neighbors, friends, and family to avoid moving any homegrown produce from their properties and to cooperate with agriculture officials working in their area.
- Help spread the “Don't Pack a Pest” message to travelers or those receiving produce in the mail or through other shipping channels.
- Share social media posts created or shared by CDFA, USDA or County Agricultural Commissioners.
Treating Queensland Fruit Fly in a Quarantine Area
This from the Ventura County Agricultural Commissioner's Office:
Basically the baiting treatment (for growers) involves 2 options: For conventional farms the material is Malathion 8 Aquamul mixed with Nulure Insect Bait and for organic growing the available product is Spinosad GF 120 Naturalyte which comes premixed with a fruit fly bait. The treatments that CDFA is performing for residents within 200 meters the QFF finds is only the organic Spinosad.
This treatment differs than a standard broadcast spray in a few ways. First, this method uses very little product. Only 20 ounces per acre are needed for the Spinosad treatment, and only 2.8 ounces per acre of Malathion is needed. Secondly, not every plant or tree is needed to be treated. The purpose of the treatment is to create spots throughout the field or orchard where any present flies would be attracted to and then die on contact. The pattern of treatment for growers under the quarantine compliance agreements is every tree or row ends on the perimeter and then every plant/tree approximately every 20ft of every 6th row inside. Thirdly, the entire plant/tree does not need to be covered, only a quick spritz or spot is needed on each chosen plant, typically somewhere on the trunk or cane if possible. This is what is meant by creating a ‘bait station'.
For growers under quarantine, a schedule of treatments must occur during one full life cycle of the fly, and also under CDFA supervision before they may harvest. Growers MUST be under compliance agreements with either the State or County before they can begin this process. Our office is offering pre-quarantine compliance agreements to growers near the current boundary so they may preemptively start the process in case the quarantine were to expand.
Growers/Residents can contact our office at pestexclusion@ventura.org or (805) 388-4222 if they have any questions regarding this pest
QFF