D1 Hazards, Pests, and Diseases Flashcards

1. Drought;
2. Excess of water;
3. Untimely rainfall;
4. Frosts;
5. Freeze;
6. Hail;
7. Fire;
8. Smoke taint;
9. Sunburn.

1. Consider irrigation as part of the initial design of a vineyard (where irrigation is permitted);
2. Choose drought-resistant rootstock, e.g. V. rupestris and V. berlandieri parentage (e.g. 110R and 140R);
3. Choose a drought-tolerant variety, e.g. Garnacha.

1. Excess water means robust vegetative growth, which can lead to delayed or less ripening in grapes;
   
   • canopy competes with grapes for sugars;
   • fruit is too shaded, thereby reducing production of anthocyanins and tannins, and overproduction of methoxypyrazines;
2. Canopy prone to fungal diseases because of high humidity;
3. Waterlogging if soils not free-draining;
   
   • reduces the amount of oxygen available to the roots, which slows growth and eventually kills the vine;
   • can lead to compaction of the soils, making them difficult to work and uncontrolled water run-off.

• If in the planning stage, plant on a slope or on free-draining soil;
• Constructing a drainage system.

At pollination: millerandage or coulure (eventual reduction in crop size and possibly quality);

At mid-season: slowed ripening;

Right before harvest: grapes bloat and sugars dilute; grapes can split, leading to grey rot.

The graft (if the vine is grafted), followed by canes or cordons.

1. Site selection;
   
   • hillsides, proximity to water, or where snow settles most thickly;
2. Choice of grape varieties;
   
   • resilient varieties will be more hardy;
3. Vine protections;
   
   • hilling up, burying vines, pruning several trunks to remove the dead ones killed in winter.

1. Advective frosts;
2. Radiative frosts.

They are caused by large volumes of cold air moving in from very cold areas.

Result from heat being lost on still, cool nights.

• Soil is heated up by the sun during the day and releases that accumulated heat overnight; the amount of heat lost depends on the level of cloud cover;
• Windless nights allow a layer of freezing cold air to form just above the surface of the soil. As cold air is denser than warm air, this freezing cold air will collect on valley floors.

1. Avoid planting in frost pockets;
2. Choose hillside sites so cold air can drain away;
3. Delay pruning, which postpones budburst;
4. Choosing a late-budding variety;
5. Train vines high off the ground (coldest air is near the ground);
6. Having bare soil between the vines (soils absorb more heat during the day and radiate this heat during the night).

1. Aspersion;
2. Wind machines;
3. Smudge pots;
4. Wax candles (bougies).

1. Perforate or knock off young shoots and leaves;
2. Grape skins can tear, inviting disease;
3. Yield reduction in that vintage (knocking off clusters) and in next year’s yield.

1. Firing rockets into thunderclouds, seeding them with silver iodide to cause rainfall rather than hail;
2. Net the fruit zone to protect ripening grapes;
3. Have a number of plots in different areas (low risk of hail);
4. Crop insurance against hail.

Grape transpiration is more limited and less effective than leaf transpiration, so in prolonged hot weather grapes can reach higher temperatures than the leaves leading to sunburn.

1. Scars on the grape skins and possible eventual death of the grapes;
2. Negative impact on overall grape quality;
   
   • browning of the grape, a bitter taste, and increased susceptibility to rot (due to skin damage);
3. Yield reduction, as sunburnt grapes must be removed at the sorting table.

1. Proper row orientation and aspect consideration for new vineyards will reduce impact of hottest afternoon sun;
2. Canopy management techniques;
3. Additional irrigation to reduce water stress (if irrigation allowed);
4. Special agricultural sunscreen spray;
5. Shading vines with a cloth or net.

• Install fire detectors and sprinklers;
• Install and maintain a water tank;
• Provide employee training for action in the event of an emergency.

From véraison onwards

Fermentation

Bottle aging

1. Analyze affected musts and/or by micro-vinifications (to release the smoke aromas) in the days leading up to harvest to assess the extent of the problem (and determine what action may be needed);
2. Smoke aroma precursors are believed to be present on the inside of the grape skin, so how the grapes are handled can reduce the effect of smoke taint;
3. Hand harvesting, gentle or whole bunch pressing, lower fermentation temperatures and reduced maceration times can reduce the uptake of compounds;
4. Flash détente and reverse osmosis can also help, but will not remove the taint completely.

• These aphids can fly and crawl through soil;
• Commonly transported by humans on young vines;
• Can be transported on vineyard equipment;
• By irrigation water.

1. Patches of vines die of drought increasingly in size year over year;
2. Vine roots are covered with the insects surrounded by yellow eggs;
3. Swellings on older roots;
4. Pale green leaf galls on the under-side of leaves;
5. Slow, stunted shoot growth and leaf yellowing appears in roughly three years, then plant dies after around five years.

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