Feed the worms…they’re good for your soil

Earthworm populations are sensitive to tillage, but using organic manures can help to increase earthworm populations under tillage.

Patrick Forrestal spoke about soil health at the recent Irish Tillage and Land Use Society’s (ITLUS) winter conference recently and explained how earthworms can benefit the soil and can benefit from organic manure addition.

“The addition of organic manures to the soil – or green manures – feeds the communities in the soil and the soil food web,” Patrick explained.

Worms do have an ability to recover from some tillage. Earthworms are sensitive to ploughing and tillage. However, reducing ploughing depth and frequency can increase earthworm populations in the soil.

“The depth that you plough can have an impact on the worm population’s ability to bounce back,” Patrick added.

The benefits of earthworms

Patrick explained that earthworms can release 50-190kg/ha/year of soil mineral nitrogen and at current prices this can equate to anywhere between €45/ha/year and €175/ha/year.

How can you help earthworms under tillage on your farm?

Feeding the biological community can reap rewards. Organic and green manures can contribute to feeding the soil food web and, in turn, can help earthworm populations.

Earthworms are drawn to organic manures – that’s where their lunch is.

A trial from grassland showed that the earthworm population, where organic manures were spread, increased from 64 to 250, just two weeks after application.

“You’re heading for an 80% increase in earthworm abundance by the addition of organic manures,” Patrick noted on one trial’s results.