Your Drains Are Only As Good As Your Last Pull

Most farmers know mole drainage works. What fewer think about is how long it keeps working and what happens to yields when it quietly stops.

Mole channels don’t last forever. On heavy clay soils they can hold up well for three to five years, sometimes longer if conditions were right when you pulled them. But on lighter or more variable ground, two to three years is closer to reality. The trouble is, there’s no alarm that goes off when they start to collapse. The water just sits.

Signs Your Mole Drainage Has Had Its Day

The signs are there if you know what to look for. Fields that used to drain within a day or two of heavy rain but are now holding water for a week. Patches of poor establishment that shift year to year, following the worst-drained ground rather than any obvious soil type boundary. Wheel ruts that appear at lighter loads than they used to. Headlands going poached when the rest of the field looks fine.

None of these on their own prove your moles have gone, but together they paint a clear picture. Dig a few trial holes across the worst areas in autumn and check whether water is moving down to the pipe drain level. If it’s sitting mid-profile and not shifting, the channels have likely blocked or collapsed.

When to Re-Mole

Timing matters as much as frequency. The classic advice holds: pull moles when the soil is moist enough to smear behind the leg but not so wet it collapses immediately. Autumn is generally the best window on arable land - soils have some moisture back in them but haven’t been hammered by winter rain yet.

On grassland the window is tighter. You want the sward intact enough to support the tractor without serious surface damage, but the soil profile moist enough to form a clean channel. Get the timing wrong and you either create a channel that collapses within months, or you trash a field surface for the sake of drainage that lasts five years and a field that takes two to recover.

Don’t Wait for a Crisis

The biggest cost of neglected mole drainage isn’t the drainage job itself - it’s everything that comes with waterlogged soil. Delayed drilling, more passes, compaction from working wet ground, reduced rooting depth, disease pressure, and at worst, complete crop failures on the worst blocks. Every one of those has a price tag attached.

A good mole drainer is one of the most straightforward investments in the machinery shed. Running costs are low, the job is quick relative to other cultivation work, and the return - in drier seedbeds, earlier entry, better rooting and reduced poaching - shows up season after season.

At Agri-Linc we stock both the Proforge MonoMole and the Proforge SubMole - giving you options whether you want a premium, fully-specified machine or a no-nonsense workhorse at a sharper price. Both are built to last and both do the same fundamental job: keep your soil working and your crops in the ground.

If your drains last did any real work two or three seasons ago, now is the time to think about whether they’re still doing it.