The effects of gale force winds are well known but the effect of even a moderate but regular prevailing wind is less obvious and yet can result in serious loss of yield and quality.

The Benefits of shelter

• Improved microclimate for better vine growth, fruit set and development.
• More suitable days for spraying.
• Possible savings on trelliswork.

The provision of shelter

Natural Windbreaks

Common examples are:

• Salix spp. (Willows) & Populus (Poplars) - vigorous, best for perimeter planting
• Ulnus spp. (Alders) - better as internal breaks, particularly recommended are the grey or black alder.
• Leylandii & Cedars - fast growing evergreens that can become too thick.

Natural windbreaks should be planted well before any vines to allow them to establish. These should be self- supporting, but if stakes are needed they should only be to one third of the tree's height and be removed as early as possible. If allowed to sway the resulting roots will be firmer.
Trees will need regular maintenance - weed control, fertiliser, trimming or topping and even root trimming. Care must be taken that they do not block drainage systems.

An effective windbreak slows the wind down by a filtering action. A solid block such as a wall or hedge of Leylandii that has become too thick will result in severe eddies and turbulence on the leeward side. This can be more damaging than the original wind. Artificial windbreaks are therefore made of small mesh netting and trees should be of a twiggy nature without dense foliage.

A permeable windbreak can reduce the wind speed for a distance up to 30 times the height of the windbreak. For maximum effect the crop should be within 10 times the height. For instance, windbreaks of 8 m high should be planted every 80 m across the vineyard.

Living trees can of course hold pests and diseases e.g. red spider mite & brown scale but on the whole they offer far more in terms of protection and beneficial predatory insects.