We have been working to find the best metric for evaluating corn silage yields. Once you have chosen which hybrid to plant, the number we are looking at is tons (35% DM) per 1000 seeds planted. I just evaluated the field across from our house which was planted 6/2 (after rye) on valley soils. It was planted at 37,972 seeds per acre (reported by the 20/20 system). In 17′ 5″ (30″ rows) I measured an average of 34 plants which mean we had a 89.5% maturation rate. Once we harvest is we will get a yield (JD Harvest Lab) and we will calculate the yield. If was assume 26 tons, then our index will be 0.69 t/1000 seeds. The dairy farm that does our work has agreed to let me calculate this on all his fields (they have all the GPS equipment). As a side note, the ears were 18 x 34 which should represent 220 bushels/acre.
Do we want to share measurements on this post.
I want to reiterate that this metric only measures how well you managed your field. It does not tell you the net return for that corn silage.
Larry
Larry –
I think this is a very biased measurement – as there is so much that goes into this number that we are not taking into consideration and if you are just looking at those numbers I don’t think we have enough information to even start this discussion – correct me if I’m wrong.
No till vs tilled
Growing degree days
Hybrid selection vs soil type
Overall soil type
Soil condition, is it tiled?
These are just a few that come to top of my list.
Why do we need to reinvent the wheel? If someone wants a single metric to track or compare CS quality then use Milk per Ton from the MILK2006 spreadsheet. If you are interested in CS yield then Milk per Acre from the same spreadsheet should suffice.
This measurement came from an agronomy group that is looking at how well people manage their fields. Looking at yield alone can be misleading as some plant 32,000/acre while others plan 40,000/acre. Michele makes good points that all affect productivity. I have given up on milk per ton or milk per acre in our consulting and have been focusing on a net return per cow per day – this include the NDFu30 concept of gut fill, the cost to grow and harvest the crop, as well as replacement commodity costs (e.g., NDFd30, and starch). As far as tons/1,000 seeds planted, it will be very close to tons/acre if all fields are planted at the same rate. Some will plant BMR at a higher population which is not taken into account when simply looking at yield drag. All good food for thought.