Farmer Focus: Fields with more manure generate highest silage yield

Harvest season 2017 is a wrap on our farm.

This past weekend the harvest company came through and was able to cut and pack all of our silage.

We harvested feed from four properties totalling 101ha. The harvest was fast, busy and successful.

In the autumn we spread both liquid and dried manure to our fields for fertilisation. Since we are an organic dairy we only fertilise with manure and nothing else.

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Our home ranch gets the liquid manure while the farther properties have dried and cleaned manure applied. We then disced and power harrowed the fields to turn the soil and mix in the fertilisation. Finally, seeds were applied with our drill seeder.

Last autumn we planted a combination of organic ryegrass, organic oats and organic triticale. We seed heavily at an average rate of 160lb (73kg) of seed mix per acre. However, we do have one site where there are no inputs and we only harvest the volunteer crop.


To harvest, the fields are first swathed and then the feed is chopped and blown into a large boxed truck that hauls the feed to our home ranch site and dumps the grass into our silage pit. 

Each truck is weighed and I am able to record specifically which field the feed comes from. From these weight records I can evaluate which management practices are the most successful as some things vary per site, such as month planted, amount of manure applied and exact seed rate.

My yields indicate the fields with both manure and seeds have a much higher yield at 2.3 times greater. The crop also appeared wetter and yielded a higher quality silage because the crop is thicker.

My farmer in cooler climates yielded about 1lb more per acre and I suspect this is due to moisture left in the crop.

And finally, my home site has the most manure applied and has nearly twice the yield per acre. At 22lb of grass silage harvested per acre the yield is very successful.

Jessica McIsaac milks 350 pedigree Holsteins in Petaluma, California, with her husband Neil. They sell organic milk and also have 6,000 laying hens.