FeedFIT: Corn Silage Harvest Tips
It doesn’t feel like it was that long ago when I submitted my last blog about harvesting high quality haylage, but long enough that as I drive the countryside, corn is fully tasseled and ears are filling. So, for today I want to focus on the king of forages: corn silage. Corn silage harvest is such a critical thing for dairies because you get one chance to get it right versus haylage harvest where you can have multiple opportunities if a crop doesn’t go as planned. Getting your game plan around how you are going to make corn silage harvest successful is an absolute must!
The first step is getting out in the fields and scouting it 3-4 weeks before you think you might be harvesting. How is overall plant health looking? Is there disease pressure (like Tar Spot, Blight, etc.) compromising plants that will force you to chop a little earlier than you are planning? We want a target dry matter of 34%, so plan around the different silage maturities you have in your fields to come as close to this as possible. And if it takes you more than a week to harvest, you are going to start on the wetter side of this target and finish on the drier side, but in the end hopefully average out close to 34%DM. Hopefully, plant health is in great condition because of using a reputable fungicide and allows the focus to be on maximizing ear fill.
Corn ear fill is what sets the starch level in the end silage product. Ideally, we want at least ½ milk line kernels when breaking an ear in half and looking at the tip-end half. Overall size of the ear will have an impact as well which is going to be out of your control but at least helps create awareness of what you might expect for starch levels. Big ears with normal size plants will typically result in higher starch silage versus shorter corn with small ears.
Chop length and kernel processing are very important; please do not skip over these two items when dialing in the chopper for harvest. In general, I like to see 26 mm TLOC (theoretical length of cut) for BMR and 20 mm for non-BMR varieties. But please work closely with your nutrition consultant to determine what TLOC makes the most sense for your herd and the rations fed. Too long of cut will create packing issues and likely look ‘trashy’ and long that can cause sorting issues at the feed bunk. Too short of cut will mainly create rumen health issues with not enough effective fiber to stimulate cud chewing and keep rumen pH in a good zone.
Kernel processing is what ensures the corn in the silage is readily available to be used by rumen bugs. Not getting this right means you will have corn in the manure and less milk which is never a good combination! So, make sure the processor is in good shape and tightened down. Do regular checks of the processing during the harvest process by separating the fodder from the kernels and making sure no cobs bigger than a thumbnail are present and there are no unprocessed kernels and mostly quartered.
Lastly, be thinking about bunker and silage pad layouts so you maximize tons stored in the least amount of square footage. Don’t think just about this year, but future years and where you will end up on a bunker or pile and how that might affect future year’s storage capacity. With newer drone technology you can do imaging of your storage area and then estimate cubic footage to better understand the amount of tons you can get in that space. Or, Google earth can be a nice way to get an overhead view of your silage pad area to help lay things out.
Starting your corn silage planning in early to mid-August will make it successful because it allows you to pivot if unexpected situations arise. Regular check-ins with cropping and feed teams will create energy around the process and keep the team dialed in on the end goal: high quality feed! Remember, once it’s in the bunker/pile you are stuck with it for the next year, so don’t settle for anything but the best! Have a successful and safe corn silage harvest season!