On guard . . .

 

On guard . . .

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 . . . or, if you’re a sporting fencer, en garde. Either way, it means to be alert, and ready to respond to any threat of danger.

Not every living thing can be ready to defend itself against attack. Plants, for example, are unable to move away from threats and many have evolved  natural defences, like thorns, or irritating sap.

Saplings are particularly vulnerable to damage from animals which like to nibble fresh young shoots or soft bark. Deer, rabbits, domestic livestock, and horses can all stunt the growth of newly-planted trees, often killing them in the process.

Woodland management involves felling or clearing trees and shrubs and then planting desired species. 

Tree guards are used to keep them safe until they have grown strong enough to withstand the predations of animals.

                Established tree shelter with strongly growing young hazel.

There are several distinct types. Tree shelters are often used in forestry when there may be many hundreds of saplings to protect. They are basically solid plastic cylinders that encase the saplings, providing a microclimate and encouraging the plants to grow upwards. They are effective but need to be well ventilated and removed before they begin to restrict growth, typically after five years. There is concern about plastic pollution and research is ongoing to find cheap, effective alternatives.   

Plastic or wire mesh guards provide a similar measure of protection but with increased ventilation and light.

Spiral guards are useful for protecting saplings in areas where small animals, like rabbits and rodents are a problem. They are no defence against deer or livestock.

More substantial guards are available in welded wire mesh or steel.

The guards used locally are recyclable plastic cylinders. Sometimes we see them lying on the ground. That is the work of human nuisances, not wildlife, but most remain intact.