What to do with hail-damaged crops
By Alberta Agriculture and Forestry
July 28, 2015 - Recent hailstorms in parts of Alberta have decimated some crops, prompting producers to look at their options.
"In a lot of cases, the crop leaves were stripped away completely and stalks are only four to six inches tall," says Barry Yaremcio, beef and forage specialist, Alberta Agriculture and Forestry, Stettler. "In these cases, this material is completely written off. However, if the crop was seeded a little later, and the head was just emerging out of the boot, there might be a chance for some second growth."
Crops that were damaged but not destroyed may be cut for greenfeed, or cattle may graze what remains. However, storm damage to crops can result in problems with nitrate accumulations, especially if the crops were heavily fertilized in the spring to optimize yield.
"It takes about four days after a storm for nitrates to accumulate to peak levels in hail damaged crops. If the plants are recovering from injury, at about two weeks after the storm the nitrates levels will return to normal and the forage should be safe to feed."
"If you can see that the leaves are drying off and you are losing yield and quality, then you need to get in and cut the crop for silage the crop or put it up as greenfeed. In that case, it's essential that it is tested for nitrates and that the levels are known before any of it is used as feed."
"Over the past three or four years, we've found that nitrates aren't as serious a problem as was once thought. However, the proviso is that you have to gradually adjust the animals to these high nitrate feeds."
Yaremcio recommends putting the herd out to feed for a couple of hours in the afternoon for the first three to four days, and then for three to four hours the next few days. After 10 days of this gradual increase, cattle can be left out to graze continuously.
"Producers should also supplement the cows through a mineral program. When switching from a regular pasture to hailed out material, one thing that will likely be low is magnesium. You'll probably want a product with two to five per cent magnesium in it. A 1-1 or 2-1 mineral will work fine as long as it has the extra magnesium to prevent downer cows."