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Ornamental Crops IPM E-newsletter, 2008

For Winter 2008

In this Issue:

Cornell IPM Team for Production Ornamentals

Christmas Tree IPM Survey Results Released

Gary Couch, NYSIPM,

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A survey of NY Christmas Tree growers was conducted in 2007 by the Ornamentals IPM Team to learn about current cultural and pest management practices. The National Agricultural Statistics Service (NASS) NY office was contracted to carry out the survey. Surveys were mailed to over 250 NY growers with follow-up phone calls made to those who did not respond initially. Over 150 growers completed the survey either through the mail or telephone interviews. The survey included questions on tree species grown, types of marketing, pest problems, management approaches, information and training sources and educational/extension/research needs. The results will be used by the NYSIPM Ornamentals team to guide future activities.

Results: Blue spruce (Picea glauca) is the most commonly grown species with nearly 50% of growers reporting over 1 acre in production. Douglas fir (Pseudotsuga menziesii), Balsam fir (Abies balsamea) and Fraser fir (Abies fraseri) are next with about 40% of growers reporting over 1 acre of each species.

Weeds (both annual grasses -- 65% and perennial weeds -- 60%) are the most common pest, though only the perennial weeds are considered difficult to deal with (46% reported them as difficult vs only 18% said annual grasses are difficult). The leading disease is needlecast(s) of Douglas fir (65% with 70% of those considering it difficult). Spider mites and white pine weevil lead the arthropod pests (40% and 35% respectively reported as common) though neither is considered particularly difficult to manage (27% and 32% respectively). Space availability is the leading factor in choosing a replanting site (65%) and only 33% test for fertility prior to planting. Few growers have an irrigation system (78% have none).

Symptoms and environmental conditions are the primary indicators used for deciding to apply fungicides (40% each) with the calendar and GDD next (20% each). Lab diagnosis is rare (3%). Insect presence (44%), GDD (22%) and the calendar (19%) are the primary indictors used to trigger insecticide use with lab diagnosis again rare (1%). Of the non-herbicide weed management techniques, mowing between the rows is by far the most common with 90%. Over 85% scout regularly, most often the owner/grower (95%) when in the field for other reasons (68%). Only 45% record their scouting results.

About 69% get their pest management information from Cornell CCE. The internet, pesticide sales reps and other growers are each used about 17%. Only 34% have Cornell‚s Guidelines to the Pest Management of Trees and Shrubs. 42% attend Industry conferences while 29% attend CCE programs. Disease/Insect and weed ID led the „What would you like to learn more about?‰ category with 58% followed by IPM (53%).

Preliminary Conclusions: Weed management leads the way as the most common pest situation that growers deal with. Though they report them as not being especially difficult to manage they do expend a great deal of time (mowing etc) and material (herbicides). Research and education on alternatives have the potential to make a positive impact on reducing the economic and environmental risks of current practices. Despite having the most common and difficult to manage disease, Douglas fir is the second most common species grown. Programming to address needlecasts seems called for. Trainings in Disease/Insect/Weed ID and on IPM through both CCE and Industry conferences and workshops should have a ready audience.

For more information or to comment on this survey please contact: Gary Couch NYS IPM Program

Grow Trees Not Weeds!

Weed Control Strategies in Christmas Tree Plantings

Betsy Lamb, NYS IPM

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Weeds in Christmas tree plantings are often the most difficult pests to control. They can reduce growth rates in young trees and affect the shape of older ones. They can provide a refuge for insects and create microclimates that diseases love. And they just get in the way of shearing, spraying and harvesting.

Planning before planting is always the best strategy. Map the planting area for differences in soil type, drainage, and elevation (for temperature differences). At the same time, map the area for the major weeds present. Take particular note of whether you have summer annuals, winter annuals or perennial weeds, as that information will help you plan your weed control practices.

Cultivation is most practical and effective before planting. Use a labeled post-emergence herbicide to kill weeds before cultivation. Especially target any weeds that are likely to be problems once the trees are planted. Vines and woody perennials are weeds to look out for!

Improving fertility levels is also easiest when preparing the field before planting. Have your soil tested to determine what you need to apply. Applying nutrients in the rows rather than broadcast will make them more available to the trees and less available to the weeds between the rows. Your trees will reward you with faster growth and better weed competition.

Even species selection can help in your fight against damage due to weeds. Choose tree species best adapted to the site and environment, as well as desirable to the consumer. Trees grown under stressful conditions are more likely to have pest problems of all sorts, and those slower growing trees are more likely to be out grown by weeds.

Keep weed control in mind when you plant your trees. Any equipment you use for mowing or spraying needs to fit between the rows and perhaps between trees in the row when they are mature.

If you are renovating an area or replanting in between existing trees, you can still do some weed control in advance. A summer mowing will result in actively growing weeds for a fall spot treatment of herbicide. Check to make sure the herbicide is labeled in your location for the weeds and the surrounding tree species, and is appropriate for the site and soil conditions. Even labeled pesticides can cause damage, especially on young trees, so be sure to shield them if you are not sure.

Not too many growers are still growing their own transplants in seed or transplant beds. If you do, weed control is essential. Even though the high density of planting would seem to help crowd out weeds, seedling evergreens don‚t offer much ground cover and may be slower growing than the weeds. Younger trees are more susceptible to herbicide damage so seed/transplant beds are the one place in Christmas tree production where mulches to exclude weeds are practical.

Once you are in the full swing of production, weed control is based on scouting -- just like disease and insect control. Scout before tree budbreak in the spring and again in July/August to identify weed problems. Spring, early summer and late summer mowings are the backbone of the weed management program. Where needed, spring pre-emergent herbicide and fall post-emergence herbicides are used for problem weeds based on the results of your scouting. Being especially vigilant during the first few years of tree growth will pay off in faster growth rates and fewer losses to other pests.

Ground cover management is of growing interest as a weed management tool. In effect, if you are promoting low growing weeds, like chickweed, between rows with mowing and suppressive rates of herbicides, you have a ground cover. You can also plant low-growing fescues or clover between the rows when you plant the trees or overseed them in an existing field. Ground covers suppress the growth of less desirable weeds, keep soil temperatures cooler, and reduce the need for mowing. Bear in mind that a groundcover can also compete with the trees so a weed free area at the base of very young trees is advisable.

Specifics on herbicides for New York State can be found in the Annual Pest Management Guide for Commercial Production and Maintenance of Trees and Shrubs or through the NYS Pesticide Product, Ingredient and Manufacturer System. Additional information on weed control in Christmas trees can be found in:

2007 New England Guide to Chemical Weed and Brush Control in Christmas Trees

Ohio Christmas Tree Producers Bulletin 670

Christmas Trees in Pennsylvania

NYS DEC Targets Greenhouse Industry for Pesticide Compliance

Neil Mattson, Cornell Assistant Professor, Floriculture

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In March 2007, the DEC conducted an operation to check the greenhouse industry for pesticide compliance. Eight teams conducted inspections at fifty-six greenhouse facilities within a 3 hour radius of Albany. Of the 56 facilities that were inspected, 52% were in compliance; 25% received a warning letter for a minor infraction and were given 60 days to correct the problem; and 23% received case referrals and penalties for breaking state or federal guidelines. Penalties for operations that were not in compliance ranged from $250 to $5,000.

Here are some of the most common problems that were found:

1) Home and Garden pesticide products were being used in a commercial setting. Remember, even if the pesticide material you wish to apply is not available in small quantities for commercial use, commercial operators must use the commercial product.

2) Organic farms received violations as they were not aware that products they are using, although „organic‰, are registered as pesticides and require compliance with the Worker Protection Standard and state and federal guidelines. Examples of these products include neem oil and insecticidal soaps.

3) Some family operations were also unaware of the DEC and the need to follow state and federal regulations for pesticide applications. If you are producing an „agricultural commodity‰ you must obtain applicator certification it you are a commercial applicator using restricted-use and general-use pesticides or as a private applicator using restricted-use pesticides. If you have any questions about a specific situation, please contact your regional DEC office.

4) Specific products had special label requirements that were not being followed. One example of this was the product Fulex which requires posting of fumigant warning signs in addition to the standard pesticide warning signs. Another example was the Pro-Mix potting media which contains the biofungicide Bacillus subtilis ˆ NYS growers must use the registered version of this product and must follow the product label requirements including respirator use by persons opening bags or filling potting machines.

DEC Region 8 Pesticide Control Specialist, Edward Hanbach, has made available a slideshow which educators may use. The slideshow covers pesticide definitions, clarifies applicator certification requirements, and points out key state and federal guidelines.

Below are some additional pesticide compliance resources.

Cornell Greenhouse IPM Guidelines

Great background information on greenhouse pesticide use and registered products for plant growth regulation and disease, insect, and weed control

NYS DEC Bureau of Pesticices

Information related to pesticide applicator certification and business registration; frequently asked questions; contact information for regional DEC offices; statewide pesticide exam calendar

NYS Pesticide Product, Ingredient, and Manufacturer System - Current Product Database

Allows you to verify product registration; search for and print product labels

Pesticide Applicator certification resources

Includes a searchable calendar of upcoming recertification course

Branching Out for 2008

Dawn Dailey O'Brien, Cornell Extension Support Specialist, Plant Pathology

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Branching Out, an IPM Newsletter for Trees and Shrubs may be just the ticket if your woody ornamentals pest management program could benefit from timely, reliable field reports and up-to date management recommendations. Faculty and staff in Cornell‚s Department of Plant Pathology, in cooperation with Cornell Cooperative Extension educators throughout the state, gather information for Branching Out via on-site scouting at selected locations from Long Island to Rochester, and they use that information together with tips from professional and trade literature to prepare articles of interest to you.

Each Issue Contains:

  • an up-to the-minute scouting report highlighting pest activity
  • an in-depth feature article
  • other items of interest to tree care professionals
  • Branching Out readers report:
  • their pest management activities are based on better information
  • they apply fewer pesticides
  • those pesticides they do apply are better directed at truly damaging pests (and at the appropriate time to control those pests).

We publish at two-week intervals starting at the beginning of April until mid-July and then shift to a three-week schedule through September for a total of 11 issues. All subscriptions run April through September. Back issues are sent to late subscribers.

Check us out at our web site to see a sample of Branching Out.

Cost and Ordering Information:

The cost of Branching Out is $40 for the 2008 season (if postmarked by March 15, the cost is only $35). To subscribe, just send your name, address, phone number and email along with a check or money order payable to Cornell University, to:

Branching Out
Department of Plant Pathology
Cornell University
334 Plant Science Building
Ithaca, NY 14853ˆ4203

Cornell IPM Team for Production Ornamentals
Betsy Lamb
State Coordinator for Ornamental Crops IPM
Ithaca, NY,
Gary Couch
Eastern New York Specialist
Brian Eshenaur
Western New York Specialist
Rochester NY
Disclaimer: Pesticide recommendations are for informational purposes only and manufacturers' recommendations change. Read the manufacturers' instructions carefully before use. Cornell Cooperative Extension and Cornell University assume no responsibility for the use of any pesticide or chemicals.
Some of the links provided are not maintained by Cornell Cooperative Extension and Cornell University. Cornell Cooperative Extension and Cornell University are not responsible for information on these websites. They are included for information purposes only and no endorsement by Cornell Cooperative Extension or Cornell University is implied.
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