B.C. Pest Monitor — Former Newsletter of IPM in British Columbia
Vol. 3 No. 2 November 1994
IPM Programs in British Columbia Cranberries
Colleen Emery, E.S. Cropconsult, Ltd., Vancouver, B.C.
British Columbia is the third largest cranberry growing region in North America. The cranberry crop, valued at over $23 million, is the third most valuable food crop in the province. Currently, there are over 2500 acres planted, about half of which is being monitored by IPM consultants. This article discusses the major pests in cranberry and how they are monitored and controlled in IPM programs.
Blackheaded Fireworm (Rhopobota naevana)
These small caterpillars damage cranberries by eating the foliage. They overwinter as eggs on upright cranberry shoots and hatch in April. The larvae initially mine the leaves and tie the leaves together with silk to make "tents". There are 3-4 generations per year; the second and third generations lay overwintering eggs in August and September. If left unchecked, fireworm feeding causes "scorching" to sections of the bog. The damaged uprights may not produce berries for two years after a fireworm infestation. Third generation caterpillars may also feed directly on the berries.
Monitoring for fireworm begins in late April to early May. Trained scouts check previous year's "hotspots" for the minute larvae in developing buds and leaves and search for frass and signs of leaf mining. They map the locations of larvae in each bog and locate infestations so that these can be monitored for second and third generation caterpillars. After the first generation has pupated, pheromone traps are set out (usually 1 per 5-10 acres or 1-2 traps per bog). Each trap is checked weekly to determine when the second generation is hatching. Hatch occurs about two weeks after the peak number of adult moths are caught in the traps.
At this time, control of fireworm relies on insecticides, timed to obtain effective control of first and second generation hatches. Monitoring programs have reduced the number of sprays for fireworm from 5-6 per season to an average of 2 sprays per season.
New Developments for Fireworm Control
In 1989, we discovered a native parasitic wasp, Trichogramma nr. sibericum in a cranberry bog in Richmond that may have greater potential for controlling fireworm than the commercially available Trichogramma minutum. Trichogramma wasps are parasites of moth eggs that have been used experimentally in cranberries for fireworm. Unlike the commercial species, who are adapted to search for masses of egg, the local wasps are able to find the singly laid eggs of fireworm. T. nr. sibericum has four generation per season and seems to work best in areas of high fireworm density. We are planning to rear this species in the near future for sale to growers.
Dr. Sheila Fitzpatrick (Agriculture and Agri-Foods Canada Research Station, Vancouver) has been developing a pheromone mating disruption program for fireworm. Sex pheromones specific to fireworms are distributed in the form of small lures placed throughout the bog. These saturate the field with female sex pheromones, sufficiently confusing the male moths that they are unable to find the females to mate. This technique seems to work best a low densities of fireworm.
In the near future, it is hoped that the use of Trichogramma and mating disruption will be used to control fireworm, thus greatly reducing or eliminating the need for insecticides.
Cranberry Girdler (Chrysoteuchia topiaria)
The larvae of this moth damage cranberry bog by feeding on roots and vines. The girdler overwinters as a larva in cocoons in the debris beneath the vines. It pupates in the spring and adult moths lay eggs from mid-May to early August, with their highest numbers in June. The larvae hatch from mid-July to mid-August and can destroy large portions of a bog in one season.
Monitoring for adults is done with pheromone traps placed in the fields. Pheromone trap catches indicate when the peak flights occur; during peak flights, scouts also walk through each field once and count the adult girdlers flying. Unfortunately, trap catches have not been reliable indicators of infestations or how much damage will occur. In the past, large damaged areas, which turn an orange-red colour, have been accompanied by low trap catches and vice versa. Because of this, there is currently no action threshold for making treatment recommendations. IPM consultants compare trap catches with those in other bogs and with previous years. Since girdlers are known to prefer feeding on weeds in the bog, the amount of weeds in the field are also considered in making the recommendations. If control measures are needed, growers can flood the bogs for 24-48 hours, during a cool, cloudy period in late August. The drawback is that this can cause fruit rot. Another option is to apply insect parasitic nematodes in mid-July to mid-August. At a higher rate of application (2 billion nematodes per acre) approximately 80% of the girdler larvae are killed. Depending on the size of the infestation, however, this may not reduce damage to acceptable levels.
Black Vine Weevil (Otiorhynchus sulcata)
The adult weevils feed on the leaves of cranberry and their larvae damage the roots. Larval feeding turns the vines red and can kill sections of the bog. Adult weevils emerge in June and lay eggs. The larvae hatch from July to September and begin feeding immediately. They overwinter in the soil, feeding on roots almost year around. Some adults may also live through the winter to lay eggs in early spring.
Monitoring for weevils begins in April with a search for larvae in the soil of known trouble spots. Vines are pulled back over a 2-square foot area to expose leaf debris, soil and roots, which is carefully searched. In mid-July, sweep net samples are taken at night to monitor for the nocturnal adults. Scouts also inspect weekly for the characteristic leaf notching from adults feeding.
Control measures are needed when weevil numbers reach the action threshold of 1 weevil per square foot. Most weevils are controlled by the fall flooding which is done for harvesting in wet-pick bogs, therefore weevils are usually only a problem on dry-pick farms. Weevils are usually not a problem in the wet-pick bogs, which make up the majority of the cranberry acreage in B.C. Nematodes can also be used in May or late August to September to control the larvae. Because the weevils usually only infest small patches of a bog, a grower can apply nematodes just to these areas using a boom or back-pack sprayer. If the weather is hot enough, spot sprays of malathion may sometimes be used to control adults in July to early August.
Diseases
There are many diseases of cranberry, but only viscid rot (Diaporthe vaccinii) and Phytophthora root rot (Phytophthora cinnamoni) are of concern in B.C.. Viscid rot is a fruit rot that causes upright shoots to die back. Infected areas of the bog are monitored yearly and noted on scouting maps. Control consists of providing adequate moisture to the bogs during dry periods to provide conditions less favourable for the disease development. Phytophthera is a soil-borne fungus that thrives on poorly drained areas of the bogs, therefore controls include improving drainage in low areas and adding sand to help with drainage. Extra fertilization to stressed plants on the edge of the dieback area is used to stimulate new root growth.
Weeds
Weeds are a continuing battle for cranberry growers until the vines are well developed, therefore we offer a fall weed mapping services to growers. Growers are given a colour coded map of the weeds in each bog, which enables them to target critical weeds and tailor the controls (herbicides, hand weeding) to the specific weeds.
IPM in British Columbia Blueberries
Barbara Peterson, Protect Department, Coast Agri Ltd., Abbotsford, B.C.
Commercial blueberry IPM programs have been available to growers in the Lower Mainland since 1989. The popularity of these services has continued to grow and in 1993, the monitored blueberry acreage had increased to 367 acres. Monitoring is an integral part of any IPM program. Routine checks for both the pests and their natural enemies indicate whether control is necessary, what control measures to use, the timing of any pesticide applications that are required and an evaluation of the efficacy of treatments.The following are some of the most common pests of blueberries in the Lower Mainland with notes on lifecycles, monitoring methods and controls.
Mummy Berry
Mummy berry is a fungus disease that causes significant losses in blueberry crops in the Lower Mainland. The fungus overwinters on the ground as mummified berries, which look like tiny, greyish-black pumpkins. In early spring, small mushrooms grow from these mummified berries and release spores. The spores infect the blueberry buds just as they are just beginning to swell. Early varieties, such as `June', `Rancocas' and `Weymouth', seem to be the most susceptible.
Achieving adequate control of mummy berry depends on applying a fungicide at exactly the right time and on using good cultural control. Since the fungicide commonly used (triforine) is a protective fungicide, it must be applied before the mushrooms open up and release their spores. However, because it does not remain on bushes for long, spraying too early is ineffective. The best time to spray varies with the location and weather conditions, therefore close attention to monitoring is essential.
IPM consultants begin checking blueberry fields in the first week of March, looking for mushrooms growing out of the mummified berries on the ground, underneath bushes and under fallen leaves and debris. The fungicide is applied is after the mushrooms have swelled, but before the cup-shaped apothecia at the top have opened to releases spores. A second fungicide spray must be applied 10-14 days after the first and a third may be needed if the weather is very wet.
Although proper timing of sprays is critical for reducing mummy berry infections, control of the disease also depends on cultural practices, which reduce the overwinter survival of the fungus. Good weed control and field drainage seem to dry out the mushrooms, so that fewer of them release spores. Raking the mummified berries into the areas between the rows and then cultivating to bury them also reduces the inoculum levels of the fungus the following year.
Winter Moth and Spanworms
The winter moth is native to Europe, but was introduced into Nova Scotia in the 1940's and Vancouver Island in the late 1960's. In 1988, Richmond residents became aware of this caterpillar when it attacked their birch trees, fruit trees and blueberry bushes.
Winter moth gets its name from the fact that the adults emerge in November and December. The females are unable to fly, but they crawl up into trees and bushes to mate and lay eggs in tiny cracks in the bark. Caterpillars hatch from the eggs in early spring and feed inside the leaf and flower buds. The caterpillars are difficult to detect at this stage because they are very small and hidden inside the buds. By the time they are easy to see, the damage is done; in severe infestations, trees and bushes are leafless, with no flowers or fruit. In 1989 and 1990, many blueberry growers lost their entire crop to these caterpillars.
Many insects introduced into new areas reach very high levels for several years and then decline and are no longer serious pests. Predators, parasites and diseases play a large role in regulating these pest populations. Winter moths seem to be following this same pattern and, after initial high numbers, they have declined in the Richmond area (though they may be increasing in other parts of the Fraser Valley). A variety of predators, including beetles, ants, birds and mice, feed on winter moth pupae after they drop to the ground in mid-May, which results in fewer moths emerging to lay eggs and fewer caterpillars the following year.
Winter is an ideal time to reduce populations of winter moths. There is no fruit and the risk of damaging berry bushes is minimal since they are dormant. The impact on beneficial insects is also minimized as they are not generally present at this time of the year. At this time of year dormant oil sprays are used to coat the branches and smother any overwintering insect eggs and larvae. Dormant oil is applied after the end of November, when winter moths have laid their eggs, but before plants break dormancy in the spring (dormant oil can burn leaves).
The key to controlling winter moth caterpillars depends on early detection, through a regular monitoring program, and quick action. Winter moth eggs begin to hatch at the end of March or in early April. Monitors begin checking fields in mid-March to make sure they are not missing the hatching period. They look closely at the buds and branches for signs of webbing and pick buds apart, using a 10X magnifying glass to look for the tiny caterpillars, which are about 1 mm long. At the first sign of the caterpillars, or their damage, the grower is advised to apply an insecticide.
Aphids
Aphids can become a problem late in the season, close to harvest. Although aphids can be controlled with insecticides, spraying so close to harvest interferes with picking. In addition, a single spray is rarely enough to control aphids through to harvest, and insecticides, such as malathion, kills both the aphids and beneficial insect that feed on aphids. Then, when aphids reinfest the field, few of the natural enemies are present and aphid numbers rapidly increase again.
An alternative to spraying for aphid control is to release ladybird beetles. Both the adult beetles and the larvae eat large numbers of aphids. They can quickly reduce aphid populations and keep them at low levels for the rest of the season. Lady beetles must be applied at the correct time in an aphid infestation and are not very effective in windy fields.
Note: See Publications section to find out how to subscribe to a newsletter on blueberry production in B.C.
Integrated Pest Management Information System Officially Opens (note: this system is no longer available)
An electronic library of integrated pest management information, called the IPM Information System (IPMIS), is now available to the public on the computer Internet. IPMIS contains information on managing pests, including insects, diseases, weeds and others. Integrated pest management methods are emphasized, including least-toxic pesticides and the use of alternatives to pesticides. Developed by the Pesticide Management Section of BC Environment, the project has been supported by funding from the Canada-British Columbia Green Plan for Agriculture, Environment Canada and Agriculture and Agri-foods Canada.
Where possible, and copyrights permit, IPMIS carries the entire text of references on-line. Notes where to find books, manuals, magazines, videos and other references not stored in IPMIS are included to give users as much assistance as possible in finding resources. In addition, IPMIS also contains information on pest management products, services and suppliers. Users can search for references or suppliers by using keywords, which they enter directly or pick from a list provided. For example, under "Search references by keyword", choosing the keywords British Columbia and Integrated Pest Management, would produce a list of references about IPM in this province. Similarly, under "Search suppliers by keyword", choosing the keywords sticky trap would produce a list of companies selling sticky traps. This search function was designed to be simple and easy to use, with all necessary instructions available on the screen. Users can also find information about specific references or suppliers by entering all, or part, of the name of a title, author or company. From the main menu, users can also read the entire text of current issues of newsletters, such as BC Pest Monitor and, in future, BC Ministry of Agriculture, Fisheries, and Foods newsletters.
Although the current version of IPMIS stores only ASCII text files, the first major enhancement to the system being worked on this winter will be to incorporate images so that pictures and scanned documents can be included. Over the winter, IPM consultants in B.C. will be contributing information to be entered into the database in the subject areas of apples and tree fruit, field and greenhouse vegetables, berries, landscapes, biological control and other pest management subjects.
How to get to IPMIS:
Step 1. Get connected to the Internet.
To use IPMIS, you need a computer* that has access to the Internet. There are a couple of kinds of Internet access:
* A full Internet connection. For example, many computers in government, universities, schools and private companies are already on networks that give them full access to the Internet. These users should ask whoever is in charge of their system whether they have access and how to get started. Some commercial service providers (see box) also offer full access to the Internet.
* An indirect link through another computer that is linked to the Internet. For example, by dialling into a local Bulletin Board Service or Free-net or other remote computer system, you use their link to the Internet. Most home computers users on the Internet have this level of access. You dial into the system using a modem, which is a piece of equipment that uses phone lines so that your computer can communicate to the remote computer. If you need to purchase a modem, make sure that you also get the software package necessary for using the modem.
It is up to you to make your own arrangements to connect your computer to the Internet, whether it is by subscribing to one of the Free-nets in B.C. or to a commercial service (see box with references).
Step 2. Find the B.C. Ministry of Environment, Lands and Parks World Wide Web server.
The IPMIS database is on a server in Victoria, belonging to BC Environment. A server is a computer that "serves" information to "clients" that contact it requesting information. IPMIS is on a World Wide Web server. To access the "Web", you need to use a "browser", which is a program that reads electronic documents, fetches them for you from different sources and allows you to search for specific information.
If you access the Internet by dialling into a Free-net or commercial service provider, you will use the browser that they have installed on their system. For example, if your local Free-Net uses a browser called Lynx 2.3, you will automatically use this if you go through the Free-net. Lynx enables you to view text files, though not images; you move around the system using keys commands that are defined on the screen.
If you have a full Internet link (this means having a SLIP, PPP or other TCP/IP connection--ask your service provider about this) and you have a fairly advanced computer you will be able to import a copy of free software, such as Mosaic, and install it on your machine. Using Mosaic enables you to display any graphics on the screen and lets you use a mouse to "click" on buttons or text links on the screen. Although the Mosaic browser is more user friendly and looks better, IPMIS basically works the same way regardless of which browser you use. For those who know how to navigate the Internet and download files, copies of Mosaic can be obtained by anonymous ftp from the National Center for Supercomputing Applications (ftp: ftp.ncsa.uiuc.edu)
Step 3. Find the IPM Information System.
If you are going through a Free-net or service provider:
Look through successive menus until you find a list of British Columbia World Wide Web servers or a list of Government Agency servers in B.C.; you may also reach the Ministry of Environment Web server through Science & Environment related menus. Once you have reached the BC Environment Web server, you will see the main menu. Scroll down the menu to the Integrated Pest Management Information System and select that option on the menu.
No computer?
In some areas, you may be able to use a public terminal provided in some libraries and community centres (see reference list). Your garden club, local environmental group or other community organization may have a computer with Internet access that you can use. You can also request a BC Environment or BC Ministry of Agriculture, Fisheries and Foods staff person to find information for you and send you a printed copy but please note that it will take several months before regional staff have access to IPMIS.
Certificate Course in Integrated Pest Management
The University College of the Fraser Valley (UCFV) offers a one-year Integrated Pest Management certificate program to train students in the methods and practices of IPM in agriculture. In addition to detailed coverage of IPM principles, the program includes courses on ecology, crop production, propagation, soils, and biology. Also included are business and communication courses to help students to learn to communicate with clients effectively, understand the business aspects of agriculture, and sell their skills and expertise. The program runs full-time over two semesters from September to April, with a one-month practicum at the end.
It is expected that graduates may find work as IPM field scouts in greenhouse, field or orchard operations. They may work for growers, an IPM consulting firm or as freelance consultants.
How to Apply
Obtain a copy of the UCFV calendar and an application form, fill it out and submit it along with a $15 application fee to the Admissions and Records office of any UCFV campus or centre. Early application is encouraged as space is limited. All students must be interviewed by the director before admission to the IPM program. Applications are accepted any time.
For complete information about the program contact any UCFV office below; application forms and calendars can be picked up at any UCFV campus or centre. There is a $3 charge for calendars, $5 if sent by mail:
Abbotsford Campus: 33844 King Rd., RR#2, Abbotsford, B.C. V2S 4N2 Tel: 604-853-7441
Chilliwack Campus: 45635 Yale Rd., Chilliwack, B.C. V2P 6T4 Tel: 604-792-0025
Mission Centre: 32335 Fletcher Ave., Mission, B.C. V2N 4N3 Tel: 604-826-9544
Hope Centre: 345 Raab St., Hope, B.C. V0X 1L0 Tel: 604-869-9991
Agassiz Information Centre: 7069 Cheam Ave., Agassiz, B.C. Tel: 604-796-2654
Publications
Diseases and Pests of Vegetable Crops in Canada. 1994
Edited by: Ronald. J. Howard, J. Allan Garland and W. Lloyd Seaman
Over 230 plant pathologists, entomologists and weed scientists in Canada contributed to this extremely comprehensive and practical guide. The text covers information on infectious and non-infectious diseases and insect, mite, nematode, mollusc and weed pests of all vegetable crops grown in Canada. Field and greenhouse grown vegetables are covered and sections are also devoted to herbs and spices, ginseng, mushrooms and other specialty crops. Each section gives detailed information on symptoms and damage, disease cycle or life cycle of pests and management methods, including resistant cultivars, cultural controls, chemical controls and biological controls. A French edition will be available later in 1994. 554 pages; 1030 colour photographs.
Available from: The Entomological Society of Canada, 393 Winston Ave., Ottawa, Ont. K2A 1Y8
Tel: 613-725-2619 Fax: 613-725-9349
Soft cover CDN$65.00; Hardcover CDN$80.00; plus $6.50 Shipping and 7% GST
Handbook of Integrated Pest Management for Turf and Ornamentals. 1994
Anne R. Leslie
Lewis Publishers of CRC Press, Inc.; ISBN 0-87371-350-8
A new, very comprehensive technical manual, including 57 detailed papers on urban landscaping and turf management of all kinds. Aimed at the professional who deal with these issues, the text covers parks, rights-of-way, commercial landscapes, home lawns, schoolgrounds and golf courses. Topics include sustainable lawn turf, healthy landscapes, specific sections on weed, insect and disease pests, biological controls, the new generation of chemicals (soaps and oils) and a very useful review chapter called "Putting It All Together".
Available from CRC press by ordering through a local bookstore. List price US$78.00. There is a reference copy in the Pesticide Management Section library (2nd Floor, 777 Broughton St., Victoria).
B.C. Blueberry News
Mary-Margaret Gaye edits this informative and interesting newsletter published twice a year by the BC Ministry of Agriculture, Fisheries and Food. Articles discuss production methods, research results, equipment, harvesting, even recipes. The newsletter also includes a summary translated into Punjabi for East Indian growers.
To be put on the mailing list contact:
Patty Cavalier, BCMAFF, 17720-57th Ave., Surrey, B.C. V3S 4P9
Tel: 604-576-5600 Fax: 604-576-5652
No charge
Integrated Pest Management in British Columbia Agriculture: 1993
R. Prasad and L. A. Gilkeson. 1994
This report describes the extent to which IPM practices are in use in the British Columbia agricultural sector. It describes the diverse activities supporting IPM, including BC Ministry of Agriculture, Fisheries and Food programs, private IPM consultants, growers organizations and marketing associations as well as research conducted by private and public sector agencies and universities. Data for three years of surveys on the acreage monitored by IPM consultants in the province are included.
Available from:
Pesticide Management Section, 2nd Floor, 777 Broughton St., Victoria, B.C. V8V 1X4
No charge.
Integrated Pest Management Report: 1993-94
Ministry of Agriculture, Fisheries and Foods
This is a summary of projects done under a special fund allocated by the Crop Protection Branch of the Ministry of Agriculture, Fisheries and Foods in 1993 for integrated pest management research. Objectives, results, funding and cooperators are described for each of 14 projects.
Available from:
D. Smith, Warehouse Services
742 Vanalman Ave.
Victoria, B.C. V8V 1X4
Cost: $5 + 7% GST and shipping
Safe and Sensible Pest Control. 1992-1994
By. L. Gilkeson
This is a series of brochures developed by BC Environment to encourage the use of safe, practical alternatives to the overuse of pesticide against common pests of home and garden. See titles available under Brochures on this web site.
Update File
Boric Acid for Carpenter Ants!
Pest managers in the structural pest control business will be happy to know that KemSan Boradust Insecticide (Commercial, reg. no. 19480) is now labeled for control of ants (along with cockroaches, fleas and bedbugs). This is good news for pest control operators wishing to use apply the least-toxic methods for controlling household pests. Boric acid dust is known to be a good control for carpenter ants, but until now, this use was not on the label of the Commercial product.
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