Workshop: Selection and make-up of fertiliser is altering

Agrii agronomist Tom Land has confirmed that the range and structural make-up of fertiliser is altering.
He spoke at a current farm workshop, hosted by Lemken, on the Ballymoney premises of John McElderry Tractors in north Co. Antrim.
Based on Land, fertilisers ought to now be assessed when it comes to their dimension, form, weight and power.
“One of many key challenges dealing with many arable farmers now’s the necessity to get fertiliser out to a spreading width of 36m,” he defined.
“If this isn’t being achieved successfully then striping throughout the crop would be the finish outcome.”
Fertiliser utility
Land pointed to the necessity for fertiliser spreaders to be regularly re-calibrated, in gentle of those altering market circumstances.
“We’re not getting the variety of European merchandise that after would have been the case. Fertilisers at the moment are changing into obtainable from locations like Egypt, Algeria and North America,” he stated.
“Which means that the fertilisers approaching to farms now are completely different to the merchandise that we now have gotten used to.
“So, Agrii at all times encourages using a tray check so as to calibrate the fertiliser spreader originally of the season.”
Fertiliser spreader tray check
Land instructed the assembly that farmers can tray check themselves or they’ll have an out of doors agent perform the check for them.
“Take ammonium nitrate as a working example. Product made in Europe is very constant. Nonetheless, as a consequence of worldwide components, we at the moment are seeing ammonium nitrate coming in from nations like Georgia,” he continued.
“And these merchandise may have completely different move traits, attributable to their differing bulk densities.
“So, earlier than farmers set-off, they need to perform an MOT check on their spreaders. This could embrace a full inspection of the hopper and the veins, which may grow to be broken over time.”
As well as, Land identified that energy take-off (PTO) speeds ought to be checked and that the drop guides are intact. The within of the tank and the likes of agitators must also be inspected.
Farmers are being particularly inspired to verify the bodily traits of the fertiliser merchandise that they buy.
“A crush check can decide how onerous a fertiliser granule is. This issue has main implications for farmers wanting to place the like of urea out to 36m utilizing very excessive PTO speeds,” he defined.
“And so the very fundamental query turns into – can the fertiliser face up to these bodily forces?
“We all know from our personal trials {that a} crush check of 3-5kg is throughout the optimum vary. Nonetheless, within the case of fetilisers yielding a check results of, let’s say, 1kg, then we all know that such merchandise won’t take a lot abuse in the back of a spreader.”
Fertiliser blends
Sieve testing blends can be advisable. Most fertiliser producers now provide a number of sieves to permit farmers and contractors determine the dimensions distribution inside mix.
Based on Land, the extra particles within the smaller sieve dimension, the more durable it turns into to unfold the product as a complete. The veins can even give the product a more durable time within the area.
“Particle distribution is actually essential,” Land harassed.
“Ideally, we wish to see a bell formed distribution, courtesy of the sieve check. A bulk density check of a fertiliser product can even ship helpful data for the farmer. E.g., urea has a a lot decrease bulk density than ammonium nitrate.”
Bulk density immediately impacts the ballistic properties and has a direct affect on the unfold width of a fertiliser. In essence, extra dense particles could be unfold wider and could be unfold with greater spinner disc speeds.
Finishing up a tray check is simple. Trays are positioned 1m aside with the 2 central trays positioned immediately adjoining to 1 one other. Fertiliser touchdown within the trays positioned on the bottom because the spreader passes are positioned into particular person glass tubes.
The unfold sample can then be visually assessed.
“The outcomes of the tray check enable the farmer to set the spreader up in order to safe probably the most even distribution of fertiliser.”
A spreader check will give a outcome when it comes to a coefficient of variation, or CV.
“A CV worth of round 15% is just about optimum within the area. Nonetheless, if this worth rises to twenty% then striping will probably be seen within the area,” Land continued.
“And at this stage, yield will probably be misplaced and fertiliser will probably be wasted.
“Understanding variation is essential. Fertiliser operators ought to consider carefully about disc heights and speeds. That is essential so as to keep away from overlapping or beneath lapping.
“And understanding the kind of fertiliser getting used can be essential.”
The unfold of fertiliser
Land made particular reference to the carrying out of veins on many fertiliser spreaders. He attributed this, partially, to the rising using polysulphates.
Referring again to the worth of tray exams, Land confirmed that an uneven distribution of fertiliser will necessitate a re-calibration of the spreader.
“Agrii undertakes a lot of crop trials on an annual foundation. We’ll fee the tray check of our spreaders originally of every season and previous to us utilizing a special product,” Land added.
“The truth is that fertiliser is now being unfold as much as 36m on both facet of the spreader. And in some instances, this determine is now rising to 42m.
“Most suppliers tweak the specs of their fertiliser ranges on a reasonably common foundation. The variation inside these merchandise can even change with every completely different season.
“These are very costly merchandise. And it’s crucial that farmers get the very best return from them.”
The bare eye will inform if striping has been a difficulty inside a crop. However by this stage, the harm has been achieved, when it comes to the uneven distribution of fertiliser.
Sap testing
Nonetheless, a extra fast manner of figuring out the spreading patterns of utilized fertiliser is by sap testing the crop in situ. That is an strategy advisable by Agrii agronomists.
Dry tissue testing determines what the plant has already metabolised by analysing the entire vitamins within the tissue pattern, whereas sap evaluation measures what the plant has absorbed from the soil however not metabolised by testing simply the liquids or sap within the pattern.
The place headlands are involved, Land confirmed that trendy fertiliser spreaders are delivering rather more correct distribution patterns.
“Part management is making this a actuality,” he additional defined.
He additionally pointed to using world positioning system (GPS) operated programs as a method of bringing but extra accuracy to bear, in terms of spreading fertiliser.
Polysulphates
Turning to using polysulphates, Land advisable an utility of 100kg/ha for cereals, 200kg/ha for oilseed rape and 100kg/ha for pulses.
“All functions ought to happen within the early spring,” he defined.
Polysulphate fertilisers are a flexible and precious supply of extended launch sulphur (S). They include potassium (Okay), calcium (Ca) and magnesium (Mg) in soluble, readily absorbed kinds.
Based on Land, they’re additionally a really fast-acting supply of plant vitamins. This relates again to their excessive ranges of solubility in water.
“The gypsum provider throughout the fertiliser is slower performing than the opposite sulphate sources throughout the product,” he defined.
“And, actually, it’s the gypsum that’s seen mendacity on the soil floor for some weeks after a polysulphate has been utilized.”

Land mentioned the relative deserves of double superphosphate (DSP) and diammonium phosphate’s (DAP) plant phosphorous sources.
“DAP is a a lot quicker performing product. It’s because vegetation will readily take up the added ammonium together with a soluble supply of phosphorous.
“DSP, however, works greatest when it’s a case of building-up basic soil phosphorous reserves.”
There are merchandise now obtainable which is able to act to launch locked-up phosphorous throughout the soil.
Land believes that it ought to now be doable to develop top of the range crops of maize, as an illustration, on excessive phosphorous soils with out the necessity for utilized DAP or DSP.
“The phosphorous required by the crop is already there. So in terms of rising maize, there’s solely a requirement to place CAN down the spout with the planted seed.”
Foliar fertilisers
Considerably, Tom Land regards foliar nitrogen (N) as a greening software, which could be utilized to cereal crops, mid-season.
This assertion is predicated on Agrii foliar feeding trials, carried out utilizing an amide N supply.
“Delivering the constructing blocks of N has to come back from a bag,” he harassed.
“Bag N fertiliser is 60% environment friendly. The remaining 40% will get ties up within the soil’s nitrogen cycle.
“Foliar N isn’t bodily including to the constructing blocks of protein within the plant. Nonetheless, it could actually play a task in mid-season, throughout dry circumstances, when cereal crops require a greening impact.”
However the place different crops are involved, Land recognized alternatives for foliar N, when utilized late within the season.
“That is actually the case with maize crops, if grown in areas the place there’s a limitation on the quantity of bagged N that may be utilized.
“Trials have proven {that a} foliar N utility late within the season will assist keep greening ranges.
“And the identical precept holds with massive cover crops, together with oilseed rape and maincrop potatoes,” he stated.
“By taking this strategy, the lively lifetime of the crop cover could be prolonged.
“There’s additionally proof to point out that the appliance of foliar nitrogen together with a sclerotinia spray will assist enhance the general oil content material of the ultimate crop.”
Based on the agronomist, trials have proven that if bagged nitrogen is utilized on the flowering stage of the crop, subsequent oil manufacturing ranges will probably be depressed.
“What we now have discovered is that foliar nitrogen utilized at this stage helps to maintain the crop inexperienced,” he acknowledged.