Sudan nitrates!!

[fnfarms1]

I planted Sudan for year 2. Good luck with it last year, this year I was about to turn cows in it today, last night I was checking it. Noticed a “white dust” on it. Mostly on stems not on leaves. They recently put limestone on our dirt road so the dust is more white. However I took couple stalks in to the county extension agent, they cut stalks open and tested for nitrates. Tested positive for nitrates. Have to send it off to get ppm type test. Do you graze it before testing for ppm? My understanding is that mines probably not horrible due to small amount of white powder, and cows will graze leaves and only go after stalk later. Also there’s good amount of grass, actually more grass than Sudan. We were drier last year than this year and no issues. But don’t need dead cows or aborting calves

 

[fnfarms1]

Test came back 4-4300/ppm nitrates…..grr just enough to worry about aborting calves so we are limiting the grazing to 3-6 hrs a day for next few days, then probably every other day for bit. I have to use the pasture so hoping for the best with slowly getting them used to it

 

[Mark Reynolds]

Don't turn the cattle into a pure stand, with nothing else to add to it (the sudan), on an empty stomach. I don't have any experience here, but your 4,300 ppm seems to be approaching a level of some concern, but not quite there yet. Never-the-less, a varied diet or limited intake seems prudent.

Found this from my Alma Mater:

https://extension.entm.purdue.edu/n...m-sudangrass-nitrate-concentrations-reported/

 

[fnfarms1]

Don't turn the cattle into a pure stand, with nothing else to add to it (the sudan), on an empty stomach. I don't have any experience here, but your 4,300 ppm seems to be approaching a level of some concern, but not quite there yet. Never-the-less, a varied diet or limited intake seems prudent.

Found this from my Alma Mater:

https://extension.entm.purdue.edu/n...m-sudangrass-nitrate-concentrations-reported/

There's a lot of Bermuda, fescue, and some crab grass in it. That's part of my less worry, not straight Sudan. There's a pond dam and old hay pile areas, roughly 1/2 acre each. that are mostly Sudan but if I bushhog those I won't get the bottom part of the stem and that's the highest concentration of nitrates. So for now I'm just limiting their grazing to 5-8hrs a day until I get them used to it, hoping for the best.

 

[Mark Reynolds]

There's a lot of Bermuda, fescue, and some crab grass in it. That's part of my less worry, not straight Sudan. There's a pond dam and old hay pile areas, roughly 1/2 acre each. that are mostly Sudan but if I bushhog those I won't get the bottom part of the stem and that's the highest concentration of nitrates. So for now I'm just limiting their grazing to 5-8hrs a day until I get them used to it, hoping for the best.

I'd say you are likely safe and have very little to worry about. One thing that I do wonder about though is that if/when you brushog, is there a brief period that the nitrates may 'spike' when the sudan is cut and is wilting? The sudan will be fine once it dries, but this 'intermittent' period could be quite troublesome. Much the same with black cherry leaves as they aren't a problem when green, they aren't a problem when dry, but don't let you cattle near them if they have broken off of a tree (typically a storm) and are now wilting.

 

[fnfarms1]

Little update, I got my second nitrate test back. The original test was 4340ppm. We got 3/4inch rain and 1.75inches a week later. 3 days after the 2nd rain I cut another batch and sent off for testing 426ppm nitrates. The rain really does seem to help. However I don’t think Sudan is for me. Going to try another crop to mix in next year

 

[fnfarms1]

I'd say you are likely safe and have very little to worry about. One thing that I do wonder about though is that if/when you brushog, is there a brief period that the nitrates may 'spike' when the sudan is cut and is wilting? The sudan will be fine once it dries, but this 'intermittent' period could be quite troublesome. Much the same with black cherry leaves as they aren't a problem when green, they aren't a problem when dry, but don't let you cattle near them if they have broken off of a tree (typically a storm) and are now wilting.

I was told a local guy had planted a bunch of cane type stuff and was mowing it with a conditioner to bale it. Problem was we were in 2nd year of nasty drought and it tested stupid for nitrates, 20,000ppm-ish.

Extension agent was saying that the problem is that nitrates never really dissipate like prussic acid or other toxins. So if that's true, I wouldn't think bushhoging would help, except you'd be losing good grass also along with your ground cover.

Only way I could see using it was to mix it in a bale processor 2-1 with prairie hay or other low nitrate feed to cut it. Not sure what he did.