Covering Round Bale Stacks Through a Canadian Winter

Most of the hay lost in a Canadian winter is not lost to snow falling on top of the stack. It is lost to water wicking up from the ground underneath and to meltwater sitting in the valleys of a badly shaped stack. A cover fixes one of those problems. How you site and build the stack fixes the other two.

This is a practical guide to outdoor round bale storage through a Canadian winter — where to put the stack, how to build it, how to cover it, and when to take the cover off again. If you are still deciding what to cover with, start with bale covers versus bale wrap first, because dry hay and baleage need opposite products.

Start with the ground, not the cover

A round bale sitting directly on soil wicks moisture up through its base all winter. The bottom of the bale stays damp, spoils, and in spring you discover the loss was never on the top at all.

Ranked roughly by cost and effectiveness:

• A drained gravel pad — the best long-term answer if you are storing bales in the same place every year
• Pallets — cheap, effective, and they keep the bale base in moving air
• Ground cover fabric — woven ground cover breaks the wicking path and keeps weeds down
• Old tires or rails — workable, and better than nothing
• Bare soil — the default, and the expensive one

Site selection does half of this for free. Pick high ground that drains. Avoid low corners where meltwater collects in March, and avoid storing under trees — you get drip, shade, and slower drying, which is three disadvantages for the convenience of being near the fence line.

How to build the stack

Single rows, butted tight

For round bales stored outdoors, the standard arrangement is a single row with the flat ends butted firmly against each other. Tight butting means very little end surface is exposed to weather, and the row behaves like one long cylinder that sheds water off its curved sides.

Leaving gaps between bales in a row does the opposite — every gap is two more weathering faces and a place for snow to pack in and then melt.

Space between rows

Rows need room between them. Set them too close and snow bridges the gap, packs solid, and sits against the sides of both rows through every thaw cycle. A metre or so (roughly three feet) lets snow fall through, lets air move, and gives you access to check tie-downs without climbing over bales.

Orientation

Run rows north–south where the site allows. Both sides then receive comparable sun through the day and melt at a similar rate. East–west rows leave one shaded side that stays damp well into spring.

Pyramids are a trade-off

The classic 3-2-1 pyramid saves ground area and is convenient to build with a loader. It also creates valleys between the bales in each layer, and those valleys collect water and hold snow.

An uncovered pyramid is usually a worse storage decision than an uncovered single row, because you have created collection points. A covered pyramid is fine — good, even, because the cover spans the valleys and the overall shape sheds well. The rule is simply: if you pyramid, you commit to covering.

Covering: shape, overhang, tie-down

Peak the top. Whatever the stack shape underneath, the cover surface should shed. A flat covered top collects snow, and wet snow is heavy — enough of it will pull a cover down into the stack and create exactly the pooling you were trying to prevent.

Overhang the shoulders, not the ground. Take the cover down over the upper sides where rain runs off, and stop there. Wrapping a stack of dry hay all the way to the ground seals it, and sealed dry hay sweats. The lower sides need to stay open so vapour can leave.

Tie down for wind, not weight. Wind is what destroys covers in Canada. A cover that lifts and slaps at the edges for four months will fail at the tie points long before UV does anything meaningful to the fabric. Use enough tie points, spread the load along a hem or over a batten rather than through a single grommet, and re-tension after the first hard freeze when everything contracts.

Cut to the stack. Roll goods are cut to length on site, which is why most operations buy hay tarps by the roll rather than as fitted covers — one roll serves stacks of different lengths year to year.

Through the winter

• Walk the stack after every significant storm. Ten minutes of re-tensioning beats replacing a cover in February.
• Clear drifts off the peak if snow builds deeply enough to flatten the shed angle.
• Watch the thaw cycles. Freeze–thaw is when covers work hardest and when meltwater finds any low spot you left in the surface.
• Do not re-tension in extreme cold beyond what is needed — fabric and rope are least forgiving then, and over-tightening stresses the tie points.

Spring: take it off at the right time

Leaving covers on into warm weather is a common mistake. Once daytime temperatures climb and the stack starts warming, a cover that is still snugly in place slows the drying you now want. Pull covers as the weather turns settled and let the stack breathe.

Then look after the cover itself:

• Let it dry fully before folding — a cover stored damp grows mould over summer
• Fold rather than bunch, and store out of direct sun
• Note any tears at tie points and repair them before next autumn rather than at first snow

A woven polypropylene cover that is dried, folded and stored properly goes back on for several seasons. That reusability is most of the economic argument for woven fabric over single-use film.

Product and supply

Sackora supplies breathable woven polypropylene bale covers and hay tarps to Canadian farms, cut to length on site from wide-format rolls. The fabric uses a HALS UV-stabiliser package compounded into the polypropylene resin during manufacture rather than applied to the surface, so protection runs through the fabric instead of wearing off it.

Details at hay tarps and bale covers and ground cover. Tell us your bale size, how many bales you are storing, and your stack layout, and we will work out the width and quantity you need.