Table 1. Insect Monitoring Guidelines for Grapes

This table covers the time from the first week of May to the four week of October (each month broken into 4 weeks). Grape Growth Stages are as follows:

• May 2nd to 4th week is Bud Break
• June 1st to 2nd week is Pre-Bloom
• June 3rd to 4th week is Bloom
• July 1st to 3rd week is Berry Set
• July 4th to September 2nd week is Cluster Tightening
• September 3rd to October 4th week is Harvest.

The table shows Major and Minor Insects when the pest may be present and the key period for symptons or activity.

Major:

Leafhoppers may be present from the 1st week of June to the 2nd week of September. Key period for symptoms or activity take place during the 4th week of June to the 3rd week of August.

Minor:

Spring Feeding Caterpillar Complex may be present from the 1st week of June to the 2nd week of July. Key period for symptoms or activity take place during the 1st week of June to the 2nd week of June.

Blossom Midge's key period for symptoms or activity take place during the 4th week of May to the 3rd week of June.

Phylloxera may be present from the 2nd week of June to the 2nd week of October. Key period for symptoms or activity take place during the 3rd week of June to the 1st week of September.

Grape Flea Beetle's key period for symptoms or activity take place during the 1st week of May to the 4th week of May.

European Red Mite may be present from the 4th week of June to the 4th week of September. Key period for symptoms or activity take place during the 3rd week of July to the 1st week of September.

Erineum may be present from the 3rd week of May to the 1st week of October. Key period for symptoms or activity take place during the 3rd week of May to the 2nd week of June.

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Table 2. Disease Monitoring Guidelines for Grapes

This table covers the time from the first week of May to the four week of September (each month broken into 4 weeks). Grape Growth Stages are as follows:

• May 2nd to 3rd week is Bud Break
• May 4th to June 2nd week is Shoots 10 to 15 cm
• June 3rd to 4th week is Bloom
• July 1st to 3rd week is Fruit Set
• July 4th to August 4th week is Berry Touch
• September 1st to 4th week is Veraison

Disease

Phomopsis:

• May 2nd to June 2nd week; basal leaves, petioles & shoots
• May 3rd to June 2nd week; rachises & fruit

Downy Mildew:

• May 4th to September 4th; young leaves most susceptible; dry hot weather stops disease; cooler wet weather starts it up again
• June 3rd to July 2nd; fruit

Black Rot:

• May 3rd to July 1st; young leaves most susceptible
• June 3rd to July 2nd; fruit

Powerdy Mildew:

• May 3rd to September 4th; 1 infection with rain &>10 C; young leaves most susceptible; development slower on older leaves
• June 3rd to July 2nd; fruit

Botrytis:

• June 3rd week; fruit
• July 4th to September 4th week; fruit susceptibility increases with maturity

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