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GENERAL INSTRUCTIONS

Preceed 850 WG Herbicide is a residual, soil-applied, pre-emergent herbicide. It is absorbed by the roots and to a lesser extent by the shoots of germinating weeds, and works by inhibiting growth in the meristematic area. Weed control is optimized when Preceed is applied evenly to moist soil just prior to incorporation by sowing and there is sufficient rainfall soon after sowing to ensure uptake of the herbicide by germinating weeds. Weed control may be greatly reduced where weed seeds have been buried by cultivation prior to application. Weed control may also be reduced where there is insufficient soil moisture for herbicide uptake or in soils prone to leaching where rainfall is sufficiently heavy to cause movement of the herbicide out of the weed seed zone. Preceed will not reliably control emerged weeds. A knockdown herbicide should be used to control emerged weeds at sowing.

Crop Safety: Preceed generally shows good crop selectivity when used as directed. The following directions will help minimize the risk of crop effects.

• Do not plant durum wheat after the application of Preceed as it may be severely damaged. Refer to Crop Rotation Recommendations for further advice.

• When incorporation is by sowing with knife points and press wheels, avoid throwing treated soil into adjacent crop rows.

• Do not use a combination of both press wheels and a covering device such as harrows or chains when sowing.

Situations which lead to concentration of herbicide in the planting row, or movement of herbicide to the depth of the crop seed, may also increase the potential for crop damage. This includes the following scenarios:

• Where deep furrows are formed by the sowing operation, soil movement into the crop row may occur due to wind or heavy rainfall soon after sowing resulting in concentration of herbicide in the crop row.

• Where soil has a high potential for leaching, heavy rainfall between application and crop emergence may result in movement of herbicide into the crop seed zone.

The potential for crop damage includes where Preceed is applied in tank mixes with other herbicides, where crop vigor is reduced due to factors such as frosts, insect attack, or crop disease, when weather-damaged seed is used, and/or with the use of some fungicide seed treatments especially in conjunction with crop varieties with short coleoptile length.

Incorporation by Sowing: Preceed should be applied prior to sowing and incorporated by sowing using knife points and press wheels, or narrow points and harrows. When incorporation is by knife points and press wheels, weeds germinating in the seed row may not be controlled. Weeds germinating from depth, weeds just about to emerge, or weeds that have emerged which are not controlled by a knockdown herbicide at sowing may not be controlled by Preceed.

Interval between Application and Sowing: Incorporate by sowing as soon as practicable after the application of Preceed, but no later than 3 days after application.

Sandy Soils: Weed control may be reduced in soil prone to leaching where rainfall after application and sowing is sufficiently heavy to cause movement of the herbicide out of the weed seed zone.

Suppression of great brome and wild oat: Preceed is most effective when grass weed seeds are present on or very close to the soil surface at the time of application. For this reason, it is recommended that Preceed is applied to uncultivated soil. As the depth of weed seeds increases, control from Preceed tends to decrease. It is rare that all great brome and wild oat weed seeds will be on the soil surface at the time of Preceed application, especially considering that these seeds may remain viable in the soil for several seasons. Plants may germinate from seeds buried by the sowing operation in previous seasons, by livestock or by weed seed self-burial mechanisms particularly in some soil types (e.g. cracking clays and sand). Therefore only partial control or suppression of the great brome or wild oat population should generally be expected. In these situations, a follow-up application with a suitable post-emergent herbicide may be required to control remaining plants.

Mixing: Ensure sprayer and nozzle filters are clean before preparing the spray mixture. Half fill the spray tank with water and, with the agitators in motion, add the correct amount of Preceed directly to the spray tank. Complete filling the tank with agitators in motion. Agitation must continue before and during spraying. When other products are to be applied in addition to Preceed, always add Preceed to the spray tank first and ensure it is fully dispersed in the spray tank before adding other products.

Application: Ensure complete and even spray coverage of the soil is achieved. Poor spray coverage may result from application to ridged or excessively cloddy soil or in situations of high stubble, plant residue, or other ground cover. A significant reduction in weed control may result where stubble, plant residue, or other ground cover exceeds 50%, and in situations where a ‘cold’ or incomplete burn of stubble results in a mass of material which can act as a physical barrier between the herbicide and germinating weeds - this can be exacerbated in header trails where there may be greater weed seed numbers and higher levels of plant residue. Weed control can be particularly affected where Preceed is applied to a barrier of stubble, plant residue, or other ground cover and there is insufficient following rainfall to transfer Preceed to the soil surface and the germinating weed seeds.

Equipment: Ground Sprayers – Standard boom sprayers only are recommended and must be fitted with bypass or mechanical agitation. It is recommended that 50 to 100 L water/ha is applied with spray droplets of a COARSE droplet size category. In some situations (e.g. high stubble loads) high water volumes may give higher levels of weed control.