Bruce Sundeen 0:00
This is the sugarbeet report, bringing you the latest information from NDSU. Throughout the sugarbeet growing season, beets will soon be lifted and following is fertilizing. How important is fertilizing this time of year and what should be used. Dave Franzen NDSU extension soil science specialist has the answers. Dave, do you have some advice concerning fertilizing in the fall?
Dave Franzen 0:24
Yeah, so fall fertilizer is a normal thing in the northern plains here in North Dakota and Minnesota. Very first thing is that phosphate and potash can be applied about any time, if you're goinging strip till or if you're going to do tillage, you can put your phosphate you can put your potash on thing not to put on as a sulfur, sulfur is not a fall fertilizer has to be put on the spring, just remember that it doesn't volatilize but it can leach. And over a long period of time, the water can move even in the clay soil. So I wouldn't put any sulfur on in the fall, it's just not worth the risk of not having in sulfur, something we have to deal with all the time.
Bruce Sundeen 1:00
What about fields that flooded in the spring or during the growing season?
Dave Franzen 1:04
If you had fields at a flooding issue, I wouldn't put any fertilizer at all on whether I worked it or not. I mean, there were some soil to move during that period of time. If you put nitrogen on last fall, you didn't get any benefit out of it at all. That's one of the restrictions that that NDSU and University of Minnesota have had for gosh, you know, 50 years is that don't put fall nitrogen fertilizer on soils and flood and so you know, where the floods and it's not the first time is it. I've been here, what 28 years and probably four or five times and during that period of time, that same areas flooded was not worth the risk. There'll be a little bit consternation, you know, some frustration, a lot of patience and the spring. But I think that's better than having a loss every once in a while too expensive, too mu ch risk of of crop injury. Remember, when you get into spring that 100 pounds of N apply that planning time is the limit no more than that, it might have to be split, when you get to that point.
Bruce Sundeen 2:01
When should fall nitrogen be applied?
Dave Franzen 2:04
The risk of nitrogen converting the nitrate and then subsequent loss, 3d Nitrification, if it's a high clay soil or leaching, if it's not, is very high before October 1. So no significant nitrogen except with goes to the phosphate. Before October 1. If you have a fertilizer company that insists that you apply it in mid September, I think I would seriously look for another fertilizer company, because that's just really poor management, you shouldn't succumb to t hat kind of pressure. October 1st at the very earliest. And then only if the soil temperature gets down to 50 degrees between six and eight in the morning, you could use your nearest NDAWN site, which there's a lot of them in the sugarbeet growing area, or you can put out your old soil temperatures and make your measurements. Once that date hits and let's just assume for fun that maybe it's October 5, that's a relatively low risk date for putting on anhydrous ammonia, but not urea. So October 5, let's say in this imaginary year is okay for anhydrous. You wait till the 12 seven days later, and it's relatively low risk for banded urea. And then another week after that, which you know, in this scenario would be October 19, for broadcast urea. So the reason for that is is that when anhydrous goes in the ground and kills all the microorganisms within that area that touches including the nitrification bacteria had it takes a while for them to eat their way into the middle, you have a little bit more time. But banded urea has a little bit of an aura but not near as big and or if you just blasting it with anhydrous you delay a little bit but still it has a little bit of delay compared to broadcast but broadcast urea doesn't have any aura at all. And so you should wait to two weeks to minimize the risk. We neve r know how long the Fall is going to be. And sometimes things really stopped in late October but sometimes it can go all the way to almost Thanksgiving before any serious freezing happens. Never before October 1 When it gets down to 50 degrees for anhydrous ammonia week later for banded urea and two weeks later for broadcast urea and then when you broadcast urea, if you're putting it within a couple inches of the surface or on the surface then you need to use a NBPT urease inhibitor something with NBPT in it which is the active ingredient and what used to be called agretain.
Bruce Sundeen 4:27
Thanks, Dave. Our guest today has been Dave Franzen NDSU extension soil science specialist. This is the sugarbeet report, bringing you the latest information from NDSU throughout the sugarbeet growing season
Transcribed by https://otter.ai