T able 5.1 E xample of a S olid B eef Manur e T es t R epor t. Lab Units 1 % and ppm. Mois tur e Content Total N

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1 24 5 Uderstadig the Soil Test & Maure Test Reports 5.1 The Soil Test Report ad the Fertilizer Recommedatio The purpose of soil testig is to measure the amout of available utriets i the soil i order to establish the amouts of additioal utriets that should be applied to meet the crop utriet requiremets. Soil testig ad fertilizer recommedatios have bee used to ehace crop productio, maximize ecoomic retur ad miimize evirometal impact o soil, water ad air. Most laboratories provide fertilizer recommedatios o the soil test reports. The fertilizer recommedatios are based o crop utriet requiremets, available soil utriets ad target yields for specific crops. I additio to the soil test results, there are several other factors that ca be used to refie the fertilizer recommedatio. These iclude: soil type, soil zoe (Saskatchewa ad Alberta), soil moisture, crop type, target yield, crop ad fertilizer prices, whether the crop system is irrigated or drylad, ad previous maure applicatios. The accuracy of the fertilizer recommedatio relies o target yields that are realistic ad based o expected moisture availability. I order to geerate a accurate fertilizer recommedatio, the laboratory must kow which crop type will be grow ad be give a realistic target yield. Target yields ca be provided by customers based o recet yield data from their operatios (such as a five-year average plus 10%). If the customer does ot specify a target yield, most laboratories will base their fertilizer recommedatios o regioal average ad optimum yield goals, which may ot be represetative of the operatio s expected yield. Uderstadig the Soil Test & Maure Test Reports Why Fertilizer Recommedatios May Differ I developig fertilizer recommedatios, each laboratory may cosider several factors that will predict a targeted crop respose at the most ecoomic rate of fertilizer applicatio. Factors such as target yield, soil moisture, crop price ad the cost of fertilizer may be cosidered whe developig a fertilizer recommedatio. Laboratories may differ i their recommedatios because they weigh the importace of the various factors differetly. It is importat to be cofidet i the recommedatios of the laboratory. If a recommedatio is give that does ot appear reasoable, a explaatio should be requested or a qualified agroomist cosulted. Some laboratories may give differet recommedatios for maure tha for commercial fertilizer. This ca occur if the laboratory cosiders the cost of fertilizer as a factor limitig the amout of fertilizer to be applied. Maure is ofte give free of charge to eighbourig ladowers or sold at a fractio of its equivalet fertilizer value. As a result, the cost of maure is assumed to be lower ad less limitig, ad the recommedatio may be less coservative. 5.2 Maure Test Reports: Uit Coversios Laboratory reports use a variety of uits to express the utriet cotet of maure. I some istaces, the results must be coverted before they ca be used to calculate a maure applicatio rate.

2 Differet laboratories report maure test results i differet uits. Scietists geerally use metric uits, but may producers are more comfortable usig the imperial system of measuremet Appedix A cotais most of the coversio factors used for utriet maagemet plaig. However, whe there is o coversio table at had, it is helpful to uderstad how the coversios are calculated. Below are various examples of coversio calculatios that ca be used with the maure test report results Coversios for Solid Maure Samples The figures cotaied i table 5.1 are used i the followig examples of solid maure coversios. T able 5.1 E xample of a S olid B eef Maur e T es t R epor t Parameter Dry Basis Lab Uits 1 % ad ppm ("as r eceived") Met r ic U it s kg/toe ("as r eceived") Mois tur e Cotet Total N Ammoium N 2, Phosphorus Potass ium all aalyses i this colum are i % except for Ammoium N which is i ppm Covertig From a Dry-Weight to a Wet-Weight Basis The utriet cotet of the maure may be provided o a wet-weight (asreceived) basis or a dry-weight basis. Sice the maure is beig ladapplied as-received, it is the wet-weight basis utriet cocetratios that are required. Laboratories report the maure aalysis o a dry-weight basis simply because the sample is dried i the lab before may of the utriet cotets are determied. If the results are expressed o a dry-weight basis, they must be coverted to wet-weight i order to calculate a maure applicatio rate. To covert back to a wet-weight or as-received value, the moisture cotet (%) must be kow. This is usually provided i the maure test report. The coversio from a wet-weight value to a dry-weight value is as follows: wet-weight value = dry-weight value x (1 (% moisture/100)) Usig total N as a example: 1.7% total N (o a dry-weight basis) 69.5% moisture cotet To covert the total N value to a wet-weight basis: wet-weight value = dry-weight value x (1 (% moisture/100)) wet-weight value = 1.7 x (1 - (69.5/100)) wet-weight value = 1.7 x ( ) wet-weight value = 1.7 x wet-weight value = 0.52% total N

3 26 Covertig From Percetage to kg/toe I the above example, the total N cotet of the solid beef maure is 0.52% total N o a wet-weight, or as-received, basis. This meas that there is 0.52 kg of total N i every 100 kg of maure. There are 1,000 kg i a toe. Therefore, there are 5.2 kg total N i 1,000 kg of maure. kg/toe = value (%) x 10 kg total N/toe = 0.52 x 10 kg total N/toe = 5.2 Covertig From Percetage to lb/to I the above example, the total N cotet of the solid beef maure is 0.52% total N o a wet-weight, or as-received, basis. This meas that there is 0.52 lbs of total N i every 100 lbs of maure. There are 2,000 lbs i a to. Therefore the coversio factor from percetage to lb/to is 20, as follows: lb/to = value (%) x 20 lb total N/to = % Total N (wet-weight basis) x 20 For the solid beef maure: lb total N/to = % Total N (wet-weight basis) x 20 lb total N/to = 0.52 x 20 lb total N/to = 10.4 Therefore, the solid beef maure cotais 10.4 lb total N i every to. Covertig From kg/toe to lb/to Some maure test reports list the utriet cotets of maure i kg/ toe, whereas may producers work i lb/to. There are 2.2 lb per kg ad there are 1.1 tos i a toe. This meas that there are 2 lb/ to for every kg/toe. lb/to = value (kg/toe) x 2 lb/to = kg/toe x 2.2 lb/kg x toe/1.1 to I the above example, the solid beef maure cotaied 5.2 kg/toe, or 10.4 lbs total N/to maure. 5.2 kg total N/toe x 2 = 10.4 lb/to T able 5.2 E xample of a L iqu id S wi e Ma ure T es t R epor t Parameter Dry Basis Lab Uits 1 % ad ppm ("as received") Metric Uits kg/1,000 L ("as received") Mois tur e Cotet 9 6 T otal N Ammoium N 58,375 2, Phosphorus Potassium all aalyses i this colum are i % except for Ammoium N which is i ppm

4 5.2.2 Coversios for Liquid Maure Samples The figures cotaied i table 5.2 are used i the followig examples of liquid maure coversios Covertig From a Dry-Weight to a Wet-Weight Basis The coversio of utriet cocetratios i a liquid maure sample from a dry-weight basis to a wet-weight basis is the same as that for a solid maure sample (see Sectio 5.2.1) Covertig From Percetage to kg/m 3 I the above example, the total N cotet of the liquid maure is 0.37% total N o a wet-weight, or as-received, basis. This meas that there is 0.37 kg of total N i every 100 kg of maure; or 3.7 kg total N i 1,000 kg. To covert liquid maure from a weight to a volume, you must estimate the desity. Desity = mass/volume The desity of water is 1,000 kg/m 3. However, the higher the dry matter cotet of the maure, the lower the desity of the maure. Sice the liquid swie maure has a very low solids cotet, we ca assume that the desity of the liquid swie maure is very close to the desity of water. For the purpose of this calculatio, assume the desity of the liquid swie maure is 1,000 kg/m 3. To calculate the volume of 1,000 kg of maure: Desity = Mass/Volume 1,000 kg/m 3 = 1,000 kg/volume (m 3 ) Volume = 1,000/1,000 m 3 Volume = 1.0 m 3 Sice there are 3.7 kg total N i 1,000 kg of maure ad 1,000 kg equals 1.0 m 3 of maure, the there are 3.7 kg total N/m 3 of maure. Therefore, the simple factor from percetage to kg/m 3 is 10, as follows: kg/m 3 = value (%) x 10 Covertig From kg/m 3 to kg/1,000 litres I the above example, we calculated that the liquid swie maure cotaied 3.7 kg total N per m 3 of maure. There are 1,000 litres i a m 3. Therefore, the total N cotet i the maure i kg/1,000 litres is: 3.7 kg total N/1,000 litres Therefore, kg/m 3 = kg/1,000 litres

5 28 Covertig From Percetage to lb/1,000 gallos I the above example, the total N cotet of the liquid swie maure is 0.37% total N o a wet-weight, or as-received, basis. This meas that there is 0.37 lb of total N i every 100 lb of maure. The desity of water is 10 lb/imperial gallo. The desity of the liquid swie maure is assumed to be very close to the desity of water. Therefore, i 100 lb of maure there are 10 imperial gallos as follows: Desity = Mass/Volume 10 = 100/ Volume Volume = 10 gallos This meas that there is 0.37 lb total N i 10 gallos of maure; ad 37 lb total N i 1,000 gallos of maure. The simple coversio from percetage to lb/1,000 gallos ca be summarized as follows: lb/1,000 gal = value (%) x 100 Covertig From kg/1,000 litres to lb/1,000 gallos Some maure test reports provide the utriet cotets of maure i kg/1,000 litres, whereas may producers work i lb/1,000 gallos. There are 2.2 lb per kg ad there are 4.55 litres i a imperial gallo. kg/1,000 litres x 2.2 lb/kg x 4.55 litres/gallo kg/1,000 litres x 10 = lb/1,000 gallos lb/1,000 gallos = value (kg/1,000 litres) x 10 Therefore, a lab aalysis of 1.5 kg/1,000 L of K would represet 1.5 kg K/1,000 L x 10 = 15 lbs/1,000 gal What is ppm (parts per millio)? Ammoium-N may be reported i parts per millio (ppm), or mg/kg (equal to µg/g) for solid maure ad mg/l for liquid maure. ppm = mg/kg = mg/g ppm = mg/l (assumig the desity of water is 1,000 kg/m 3 ) Covertig mg/kg to kg/toe for Solid Maure There are 1,000,000 mg i a kg. There are 1,000 kg i a toe. kg/toe = mg/kg x kg/1,000,000 mg x 1,000 kg/toe kg/toe = mg/kg / 1,000 kg/toe = value (mg/kg) / 1,000 I the above example, the ammoium N cotet of the solid beef maure is 684 mg/kg o a wet-weight, or as-received, basis. -N/toe = 684 / N /toe = 0.7

6 Covertig mg/kg to lb/to for Solid Maure There are 453,600 mg i a lb. There are kg i a to. lb/to = mg/kg x lb/453,600 mg x kg/to lb/to = mg/kg / 500 lb/to = value (mg/kg) / 500 I the above example, the ammoium N cotet of the solid beef maure is 684 mg/kg o a wet-weight, or as-received, basis. -N /to = 684/500 -N /to = 1.4 The result ca the be coverted to imperial uits usig the coversio for kg/toe to lb/to as provided above (see Sectio 5.2.1). Covertig mg/l to kg/1,000 L for Liquid Maure Sice the desity of liquid maure ca be assumed to be the same as that of water, the mg/kg ca also be reported as mg/l. I oe litre there is: kg/l = mg/l x kg/1,000,000 mg I 1,000 litres there are : kg/1,000 L = mg/l x kg/1,000,000 mg x 1,000 kg/1,000 L = value (mg/kg) / 1,000 I the above example, the ammoium N cotet of the liquid swie maure is 2,335 mg/kg o a wet-weight, or as-received, basis. -N/1,000 L = 2,335 / N/1,000 L = 2.3 Covertig mg/l to lb/1,000 gallos for Liquid Maure There are 453,600 mg i a lb. There are 4.55 L i a Imperial gallo. I oe gallo there is: lb/gal = mg/l x lb/453,600 mg x 4.55 L/gal I 1,000 gallos there are: lb/1,000 gal = mg/l x lb/453,600 mg x 4.55 L/gal x 1,000 lb/1,000 gal = value (mg/kg) / 100 I the above example, the ammoium N cotet of the liquid swie maure is 2,335 mg/kg o a wet-weight, or as-received, basis. -N/1,000 gal = 2,335 / 100 -N/1,000 gal =

7 Phosphorus versus P 2 The maure test results may be expressed as total elemetal P or P 2. To be cosistet with the reportig of the P cotet of commercial iorgaic fertilizers, P fertilizer recommedatios are provided o the soil test report as P 2. For this reaso, it is helpful to be able to covert betwee the two. To covert from P to P 2 simply multiply the value for P by 2.3 Example: Liquid swie maure cotais 0.11% P The maure will provide 1.1 kg P/1,000 L (see Sectio 5.2.2) P 2 = 2.3 x P P 2 = 2.3 x 1.1 kg P/1,000 L Therefore, the liquid swie maure will provide 2.53 kg P 2 /1,000 L Potassium versus K 2 O The maure test results may be expressed as total elemetal K or K 2 O. To covert from K to K 2 O, simply multiply the value for K by 1.2 To be cosistet with the reportig of the K cotet of commercial iorgaic fertilizers, K fertilizer recommedatios are provided o the soil test report as K 2 O. For this reaso, it is helpful to be able to covert betwee the two. Example: Liquid swie maure cotais 0.15% K The maure will provide 1.5 kg K/1,000 L (see Sectios 5.2.2) K 2 O = 1.2 x K K 2 O = 1.2 x 1.5 kg K/1,000 L Therefore, the liquid swie maure will provide 1.8 kg K 2 O/1,000 L