North Carolina Cooperative Extension Service

CTN - 032

Christmas Tree Notes

IPM CHECKLIST IN ESTABLISHED FRASER FIR CHRISTMAS TREE PLANTATIONS

Integrated pest management or IPM is a sustainable approach to controlling pests by combining biological, cultural, physical and chemical tools in a way that minimizes economic, health, and environmental risks. Why is IPM important? By adopting IPM practices a grower can potentially use fewer pesticides and fertilizers, improve tree quality and growth, protect beneficial organisms, and preserve soil and water resources--all while managing pests in the most efficient way possible.

Growers may already be doing some practices that are considered IPM and don't know it. This checklist is designed to give ideas of some additional practices that may be adopted so that tree production can become closer to the IPM ideal.

These suggestions are for established Fraser fir Christmas tree plantations. Proper site selection and site preparation are also important considerations in IPM. For more information on these activities, contact your county extension agent.

STEP ONE: Getting IPM started.

Attend IPM training. An IPM program is based on a thorough understanding of cultural practices, fertilizers, pesticides and pest biology. New skills in scouting and record keeping are required. The North Carolina Cooperative Extension Service has training opportunities in Fraser fir IPM to help growers learn these skills. Contact

your local county center for more information on IPM educational programs.

Set goals. Make IPM and reducing pesticide use an objective for the Christmas tree plantation. Write down this objective someplace where it can be seen often.

Start small. Don't try to change everything at once. Set achievable goals for the next 6 to 12 months. Experiment in a small way at first. It may take several months to become confident in pest scouting and to learn new practices.

STEP TWO: Keep accurate records.

The cheapest and easiest practice to become more efficient in controlling pests is to keep accurate records. Have a map of each field block. Record where transplants

come from and when they are set out. Record all scouting visits and all fertilizer, herbicide, and insecticide applications. Keep soil sample and plant tissue sample reports for a block in the same file. Detailed records can help determine the cause of problems that may develop. Pest control practices can be improved by learning from past mistakes.

STEP THREE: Practice regular scouting.

Regular scouting should be a major aspect of any pest management program. Beginning in early spring and continuing throughout the summer, scout for each potential pest on a schedule appropriate to its life cycle as described in the checklist.

Ground cover management: Ground cover management affects all aspects of tree production from fertilizer uptake, to soil erosion, to pest predator populations. The goal of good ground cover management is to increase the benefits of weed cover while decreasing weed competition with trees. Be aware that ground cover management will and should change as trees mature.

• At no time through the growing season are trees grown on bare ground.

• Pre-emergent herbicides are only used in the tree row, not broadcast.

• An inventory of all the types of weeds in each field is taken every year in late summer.

• A ground cover management plan (pre-emergent and post-emergent herbicide use, mowing, ground cover seeding, etc.) is devised each fall based on the general weed mix, problem weeds, and the size of the trees for each field.

• Problem weeds are eliminated at the appropriate time of year.

• Weeds that can be managed are suppressed with chemical mowing techniques.

• Weed growth stage and height is monitored to determine the appropriate timing of herbicides.

• Each backpack sprayer is calibrated by the operator so that an accurate
• herbicide rate is applied.

Fertility: Proper fertility including proper soil pH, phosphorus, calcium and other nutrient levels can reduce pest problems by reducing the number of years in a rotation and by making the tree stronger to ward off pests. A long-range fertility plan should be developed for each field to achieve and maintain optimum soil fertility.

• A representative soil sample is taken with a soil probe. Soil samples are taken annually until soil fertility goals are reached. Soil samples are then taken bi-annually to maintain optimum soil fertility.

• Plant tissue samples are taken the 3rd year in the field and the year before sale in the fall.

• Soil samples and accompanying plant tissue samples are taken anytime there are problems with poor color or growth in the trees. Accompanying these are similar samples from good growing trees in the same field for comparison.

• Annual prescription fertilizer plans are developed and followed each year based on soil and plant tissue reports within the context of the long-range fertility plan.

• Fertilizers are spread to achieve maximum soil coverage.

Balsam woolly adelgid (BWA): Proper BWA control requires early detection of tree infestation and thorough pesticide coverage. Care should be taken that pesticides applied to control BWA do not make spider mites worse, since broad spectrum insecticides can kill beneficial predators that keep mites in check.

• Trees are scouted for the presence of crooked tops each year from the time they are waist-high until harvest. Scouting is done from July through October.

• Trees with crooked tops are examined for the presence of live BWA by removing bark with the white wool and examining with a handlens.

• Trees are treated, if necessary, using a pesticide which does not kill mite predators, or during the winter when predators are not present.

• If a pesticide treatment is necessary, it is applied with a hydraulic sprayer and hand-held gun, treating from two directions and no more than two rows at a time to completely cover the entire tree.

• Large Fraser fir near the field which cannot be adequately sprayed for BWA are removed.

• Trees with BWA that have not had a straight top for two years or more are cut and removed before spraying.

Spruce spider mite (SSM): Control of the SSM requires integrating several management practices including ground cover management and pesticide selection. Adequate scouting is required to prevent damage from SSM.

• Trees are scouted throughout the growing season for SSM. The schedule for scouting trips is determined by the size and value of the trees, and the amount of rainfall throughout the growing season.

• Treat promptly with an appropriate pesticide if SSM numbers exceed treatment thresholds.

• The same miticide is not used every time treatment is necessary as mites can become resistant.

Balsam twig aphid (BTA): The BTA is easily controlled with proper timing of pesticide applications.

• Trees are treated for BTA the year before sale and the year of sale. Younger trees are only treated if high levels of past damage indicates it is necessary.

Rosette bud mite (RBM): The RBM is a slow spreading pest that can decrease tree quality or increase number of years to harvest.

• Transplants with RBM are not planted in fields that do not already have this pest.

• Young trees are not interplanted with old trees in fields that have RBM present.

• Trees with RBM are harvested as soon as possible.

  If a pesticide treatment is necessary, it is applied in early to mid-June with a hydraulic sprayer and hand-held gun, treating from two directions and no more than two rows at a time to completely cover the developing vegetative growth.

Phytophthora root rot (PRR): The spread of PRR is enhanced by increased soil moisture and soil movement from infested to uninfested areas. Disease development increases as the inoculum density of the fungus increases. The key to PRR control is disease prevention.

• Plant only healthy, disease-free Fraser fir transplants.

• Plant Fraser fir only on suitable sites.

• In fields where PRR has developed, problem areas are sodded over to prevent soil, water and pathogen movement.

• Care is taken that soil from infested areas does not contaminate the rest of the farm.

• In areas of the field where trees have died from PRR, trees are removed as soon as possible.

• Do not replant Fraser fir in areas of the field where trees have been positively identified as being killed by PRR.

Other pests:

• Damage from other pests such as Cinara aphids, white grubs, rust mites and others are noted when scouting for SSM and BWA. Additional scouting trips for these pests are made when necessary.

Pesticide choices and application:

• Trees are only treated for pests when scouting results determine it is necessary.

• Spray equipment is in good working order. Nozzles are cleaned and replaced regularly.

• Spray water is tested for pH and water softness. If problems with water quality exist, corrective measures are taken.

  The pesticide label is carefully read and completely followed each time a material is applied.

• The least-toxic labeled pesticide is chosen.

• The same pesticide is not used year after year.

• Only one pesticide is used for any given pest. Other materials such as surfactants, spreader-stickers, or foliar fertilizers are only added to the spray mix if recommended on the pesticide label.

• Thorough coverage to maximize pesticide efficiency is practiced.

• Pesticide control is assessed from 1 to 4 weeks after application to determine if retreatment is necessary and to improve pesticide application techniques.

  Recommendations for the use of chemicals are included in this publication as a convenience to the reader. The use of brand names and any mention or listing of commercial products or services in this publication does not imply endorsement by the North Carolina Cooperative Extension Service nor discrimination against similar products or services not mentioned. Individuals who use chemicals are responsible for ensuring that the intended use complies with current regulations and conforms to the product label. Be sure to obtain current information about usage and examine a current product label before applying any chemical. For assistance, contact an agent of the North Carolina Cooperative Extension Service in your county.