Appendix

Chemical Control Alternatives

General Safety with Insecticides

The supervisor must explain to employees, in detail, how to handle insecticides and insecticide-treated seedlings in a safe manner. Employees must know what to do in case of an accidental contamination of skin and clothing or if symptoms of pesticide poisoning appear. The supervisor must not only provide this information, but make certain that employees work in a safe manner. The supervisor should stress the need to wash hands before eating, handling cigarettes or chewing tobacco, performing bodily functions, or before leaving the job. Wash basins, hand washing detergent, water, and towels must be provided at the job site. Torn -gloves must be replaced immediately, and workers with blisters and open sores on hands must be given jobs that do not involve handling insecticides or treated seedlings.

Imidan Top Dip (Imidan 50W)

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Treatment. - The tops of seedlings, down to and including the root collar, are dipped in an aqueous suspension of 4 percent active ingredient Imidan. An adjuvant-either Plantgard or Nu-film 17 mixed at 2.7 percent (14 ounces per 4 gallons, or 27 ml per liter) by volume-is optional, but recommended in "hot" areas or if high rainfall is expected. (Imidan can also be used as a post-planting spray. See information under Dursban Spray.)

Operational procedures. - Dip seedlings in loose bunches in the suspension for 10 to 15 seconds, ensuring good coverage of the lower stem (figure 7). Dipping can be done at the nursery prior to packing seedlings or at the planting site prior to planting.

Precautions.- Dip must be freshly mixed daily. Do not let it stand overnight. Agitate the dip frequently to keep the wettable powder in suspension.

Figure 7. - Pine seedlings may be dipped at the nursery prior to packing or in the field prior to planting.

Seedlings must be dipped in loose bundles. Dipping whole, tightly packed 9 open-ended bundles of 500 to 1,000 seedlings is not recommended because the insecticide will not penetrate and coat the entire lower stem of all the seedlings. The effect of Imidan on the root system has not been determined, so avoid covering roots with this insecticide.

Roots may dry excessively when seedlings are dipped at field sites. Therefore, dip in the early morning, before wind and temperature increase. Treated seedlings should be heeled-in or returned to a moist atmosphere in polybags or bundles as soon as possible.

Hand planters can use either planting bags or planting buckets. Water in planting buckets must not go above the root collar. Disposable polyethylene bag inner liners could be used in buckets and bags to prevent a buildup of insecticide.

Safety. - During the mixing of Imidan 50W, a respirator, goggles, liquid-proof coveralls or apron, rubber boots and rubber gloves must be worn. Imidan 50W is a wettable powder which should be wetted thoroughly with a small amount of water to make a slurry before adding the total amount of water. The powder will puff up out of the container and be carried by the slightest breeze during this operation, so it is imperative that a respirator and goggles be worn during mixing, and that other workers stay well away from and upwind of the mixing site.

During the dipping operation, a face shield should be worn to protect the eyes and face from splashing. Rubber gloves, apron or liquid-proof coveralls and rubber boots should also be worn.

Immediately after dipping the seedlings - whether in the nursery or in the field-place them on a tray or shallow container to catch the excess insecticide. This will prevent a buildup of toxic wastes in the area and the excess dip can be reused. Catch additional drippings with a disposable absorbent. When Imidan dip is spilled on nursery work tables and floors and allowed to dry, a dusty toxic residue results. This type of residue should be prevented because it might be inhaled. Planters should wear rubber gloves.

Furadan Granules

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Treatment. - At planting time, broadcast Furaden granules (10 grams or I teaspoon for 10G; 7 grams or 3/4 teaspoonful for 15G) in a 6-inch (15 cm) radius circle around the base of the seedling. Cover the granules with a light layer of soil or incorporate them into the soil. You may also apply granules in the planting hole at a reduced rate of 2to3gramsof 10G(1.3to2.0g of 15G).

Operational procedure.-The granules can be applied by the planter or a second worker who is following behind. The granules can be applied with a scoop or metered out by an applicator attached to the planting bar (figure 8). A granule applicator on a planting machine could be devised.

Precautions.- Granular Furadan at rates higher than the recommended dosage can burn the foliage and even stop growth. Therefore, take care to apply the correct amount. Do not exceed 10 grams of 10G (7 grams of 15G) per seedling when broadcasting. Brown tips on old and first flush foliage may occur with the above rate of Furadan, but this is not serious and it will not affect growth rate or survival. If Furadan is placed in the planting hole, no more than 3 grams of 10G (2 grams of 15G) should be applied to prevent harmful effects. Test planting hole treatment on a small scale in order to check out any damage to the seedlings under local soil and climatic conditions.

Safety. - Open the bags and load granule reservoirs in an open, well-ventilated place. Take care not to inhale any Furadan dust. Persons handling and applying the granules should wear rubber gloves and goggles. Dispose of empty bags in a proper manner.

Furadan Root Dip (Furadan 4 Flowable)

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Treatment. - Dip or spray seedling roots with a kaolin clay water slurry containing 1 percent active ingredient Furadan flowable formulation.

Operational procedure.-The roots of the seedlings can be dipped or sprayed prior to bundling or bagging at the nursery, or they can be sprayed in the polybag. Dipping can be done in the field before planting. Under normal cold storage, Furadan should remain stable.

Figure 8.- Granule dispenser attached to the planting bar for surface
or in-hole application of Furadan granules.

Precautions.- The Furadan-clay slurry suspension can be used for 2 to 3 days if the pH is 7 or below. The insecticide will break down more rapidly if the pH is greater than 7. Agitate the suspension thoroughly if it is held overnight; also stir it frequently during the day. When seedlings are dipped at field sites, be sure the roots do not dry out. (See "Precautions" under Imidan Top Dip). In hand planting operations, planters should use planting bags instead of buckets so the insecticide is not washed off the roots. Polyethylene bags can be used as disposable inner liners to prevent contamination of planting bags.

Safety. - When treating seedlings at the nursery, take care to contain the slurry and prevent spills. Spray the roots inside the polybags. Use low pressure to avoid fine droplets, which could be inhaled. If roots are dipped, be sure that the excess slurry drains back into the dipping tank or is absorbed by material in the bundle or polybag or material which can be disposed of periodically without contaminating work tables or the floor. Any spillage that is allowed to dry on nursery floors or work tables will lead to a dusty toxic residue that might be inhaled later. Workers exposed during the application and handling operation must wear face shields, liquid-proof coveralls, rubber gloves, and rubber boots.

Persons handling treated seedlings during the planting must wear rubber gloves and face shields. Take care to prevent spattering of the slurry by disentangling roots before placing seedlings in planting bags or bins of planting machines. Used seedling bags should be disposed of in a proper manner.

Dursban Spray (Dursban 4E)

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Treatment. - Spray the stems of seedlings to the point of runoff after planting, with a 2-percent active ingredient aqueous spray.

Operational procedure. - Spray seedlings with low pressure back-pack sprayers (figure 9).

Safety.- Workers should wear liquid-proof coveralls or aprons, rubber boots, goggles, and respirators when mixing spray. They should wear rubber boots and rubber gloves and stand upwind while spraying.

Figure 9.-Backpack sprayer for post-planting treatment of seedlings with Dursban or Imidan.