Grain producers may have been cursing the province’s dry spell in the first week of June, but it was good news for forage growers looking for their first cut.
John McGregor, co-ordinator of the Manitoba Forage and Grassland Association’s Green Gold program, said farmers saw between seven and 10 days of good drying weather around this year’s Hay Day announcement.
Hay Day, when relative feed values (RFV) fall to the optimal 170 points, was announced June 4-5. While 150 RFV is ideal in finished feed, the Green Gold program recommends a 20-point cushion at cutting, due to harvest loss.
Silage has yielded between two to five tonnes per acre with an average of three, according to McGregor.
“It looks like a very good cut,” he said. “Probably considerably better than last year and we haven’t had any rain on it yet so the quality, I’m expecting, is going to be way superior to things that we saw last year.”
All six Green Gold fields in the southeast were cut by June 7 while clipping had begun in the west near Virden, McGregor reported.
Eastern stands developed ahead of other regions in the province, Green Gold reported. By June 5, lab-tested RFV in the east had dropped to 161 points with 23 per cent protein while plants averaged about 24 inches tall. Warm weather during the first weekend of June had plants leaping three inches while RFV loss jumped to seven points per day. All fields were in the late-bud stage as of June 5.
Previous Green Gold results show alfalfa will lose five RFV points on average per day.
Western and central regions lagged behind the east as of June 1. Central Manitoba was still testing at 184 RFV, followed shortly by the west at 182 RFV. Both areas were dropping by six points a day.
Forage in the Interlake showed well-above-optimal cut levels, but reported that RFV was dropping at twice the average expected rate. The Interlake registered 200 RFV points and 27 per cent protein in lab results June 1, but reached only 14 inches high.
Both regions were expected to drop to 170 RFV by June 4.
Winterkill in central and southeast Manitoba lowered yields for some producers.
“I only know of one field that we are using where there was a fair bit of winterkill and, in that case, the yield was considerably lower than what we’re seeing as an average right now,” McGregor said.
The Manitoba Forage and Grassland association blamed mid-winter thaws for the damage, citing lack of insulation after the snowmelt as well as frozen pools cutting off oxygen to the plants below.
Calvin Grienke of Steinbach is among the farmers affected. The dairy producer harvested 350 acres of forage land this year.
“It probably isn’t going to be nearly as good as last year, but it was still worthwhile,” he said. “There is less alfalfa content in it and more grasses, but grass feeds good too, as long as you cut it early enough.”
Despite lower yields, Grienke says he expects his forage to feed his 210-cow dairy herd.
“We just won’t have as much to sell,” he said.
McGregor warned that fields with high grass content may have lower RFV than Green Gold estimates, which are based on alfalfa alone.
Optimal cut times for an alfalfa-grain mix may be four to six days earlier than pure alfalfa, McGregor said. His results have shown a 20-35 RFV drop between forage mix and pure alfalfa.
Rating from the sky
An ongoing experiment hopes to see if RFV can be measured by drone.
This year is the second that the Green Gold program and Winnipeg’s M3 Aerial Productions have partnered, comparing aerial NDVI (normalized difference vegetation index) images with lab-tested samples taken at the same time.
NDVI is used to detect plant stress, problem areas in a field and crop stages by measuring reflected near-infrared light.
“What they’re trying to do right now is they’re trying to take a look at the information that we’re generating on the ground and trying to do some sort of a correlation as to what they’re seeing from the air… if they can replicate what we’re seeing on the ground, then farmers will be able to use things like drones and aerial photography to kind of predict when we’re getting close to the time to cut alfalfa,” McGregor said.
Matthew Johnson, owner of M3 Aerial Productions, said data is still being analyzed from last year although initial results showed promise.
“What we saw last year is, as the relative feed value went down as the plants developed, we could see it fairly clearly in the NDVI and so, this year, we wanted to double-check on that,” he said.
Data from two out of the six test days last year was skewed due to environmental factors such as cloud cover, Johnson said, while weather limited flight time in 2017.
He hopes to hit the field with the Green Gold program again next year before drawing more definite conclusions.
Forage evaluation would be the drone operator’s latest foray into the farm industry. In 2016, Johnson expanded his drone photography service to include agricultural NDVI and aerial elevation mapping.
“Over the last few years it’s been building steam,” he said. “It’s a snowball that’s been slowly building. Not everyone’s on board with the idea yet, so I’m just interested in collecting research and this was a good way to be able to collect research — the fact that they’re taking these cutting samples. There’s not a whole lot of opportunities that we’ve come across where we can compare the NDVI analysis to the scientific measurements taken through cutting samples.”
Johnson noted the depth of data available through the Green Gold program as a valuable resource, which has been collecting samples for over 20 years.