The Gentle Art of Tree Shelter Construction

In order to pursue its aim of re-establishing trees in fields and hedgerows,  Trees for Cotherstone had to decide on a method of protecting its newly planted saplings until they grow sufficiently large and able to resist damage from a number of agencies;

The Bad guys

Voles       Eating basal bark especially in hard winters

Rabbits     Browse shoots and eat bark
If potential damage Is restricted to these small species then proprietary plastic or mesh tubular guards may do the trick.

Roe Deer    Browsing up to 1.2 metres and fraying of saplings to remove the velvet from their horns.
Taller, 1.2m, tubular guards should offer adequate protection, however these solutions are only appropriate where livestock are strictly excluded because...

Livestock   Will browse much more heavily and trample what they don't eat. Horses in addition will bark strip even quite mature, soft barked trees.
Here the only answer is a stockproof enclosure of suitable height.

Weeds       Compete with the young tree for water and nutrients and by over-topping it deprive it of light.
A mulch mat will suppress vegetation and retain moisture in the soil. It is not a substitute for regular weeding until the tree has grown out of danger.

The Tree Protection System

In most cases the trees we plant have to be protected from all these agents and we have designed a tree shelter (see diagram) which is substantial enough to keep out livestock and deer and is supplemented with a plastic tube against rabbits and smaller vermin.

The guard, stake and rabbit net will be removed once redundant but the outer shelter is expected to remain for many years. A carpet square mulch mat is applied around the base of the tree.  The design is robust and effective, easy to erect and economical of materials.

This protection is not cheap (materials approx. £25 at present) but there is absolutely no point in trying to establish a field or hedgerow tree without it.

Notes on construction

Certain of these operations may raise Health and Safety issues. A Risk Assessment may be required.

The size is such that a 12ft fence rail can be cut to fit around the top. ie slightly less than 3ftx3ft to allow for the overlap of the cut rail at the corners.

• A template is used to mark out the positions of the posts on the ground.
• The posts have to be vertical and parallel and in most ground conditions this can only be achieved by preparing holes with a pinch (crow bar).
• The planting hole can also be dug and refilled at this stage. This makes the planting operation a lot easier later on in a confined space.
• It is easiest to drive the posts with a 'Drivall' type post knocker with extension handles which can be used safely by 2 people standing on terra firma.
• A third person holds the post in position with a long handled grip and periodically checks its alignment with a spirit level.
• Drive the posts to the required depth ,(6ft to 6ft 3") rather than cut tops off as this compromises the preservative treatment.
• Post points should be at least 8-9". Blunt 'pencil sharpener' points are difficult to drive by hand.
• On slopes the top of the shelter may also slope otherwise the top side may not be high enough to deter cattle. For appearance always keep opposite top edges parallel.
• Nailing and stapling is much easier if a heavy hammer (mell/sledge or similar weight) is held behind the post at point of impact.
• Two precut lengths of lightweight (C8/80/15 grade) mild steel stock netting are stapled tightly to the posts and can be tensioned using an universal fencing tool. Fixing net on a slope can be difficult if following the contours.
• Leave the fourth side loosely fastened for access until the tree has been planted.
• Strips of barb down the corners will deter cattle from rubbing and possibly pushing posts over.
• Some sheep may push their heads through the stock net to get at the tree. This can be prevented by suspending a cylinder of rabbit net around the tree inside the shelter. It can be removed and re-used at a later date.
• At planting the support stake should be driven in first to prevent damage to the roots.
• A plastic mesh guard is slipped over the tree and pressed into the soil to keep out rodents.
• It is fixed to the stake using tie-wraps and turned over at the top to provide a round edge that will not abrade the tree.
• Old carpet makes excellent mulch mats. Cut 2ft squares with a slit to the centre and a short cross cut to accommodate the tree.  Place it around the plastic tube, not under it, and weight with stones if necessary (not divots).

Materials List (letters refer to diagram)

A   4 x 8ft x 2.5-3" top diam. Round posts pressure CCA treated
B   I x  12ft x 4wxl.5w fence rail
C  2 x 12+ft lengths of C8/80/15 field netting
D  I x 10ft length of rabbit netting
E  4 x 6ft lengths of barb wire
F  30mm x 3mm staples galvanised
G  100mm nails galvanised
H  I x 3ft treated or hardwood stake
I   I x 2ft plastic mesh tree guard
J  8" tie-wraps
K  I x 2ft square of carpet

Tool List

• Square template for size of shelter with diagonal brace
• 5ft pinch bar
• B Drivall" with extension handles
• Post grip with long handle
• Spirit level
• Spade
• Bolt cropper type wire cutters
• Old garden shears for cutting rabbit netting
• Claw hammers
• Lump hammer
• Heavy hammer-mell or sledge
• Universal fencing tool