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circumference of the soil sample that had contact with the auger during collection. A 341 second sterile spatula can be used to collect the inner core sample from the center 342 opening of the auger. 346 experimental design and what is required to have defensible data prior to collecting a soil 347 or starting an experiment. 348 Judgement samples are those resulting from an individual deliberately avoiding a 349 particular area, thus exercising judgement in selecting sampling sites, and therefore are 350 highly biased and not recommended for most purposes. Judgement samples should be 351 reserved for instances when the individual collecting the sample is only using the sample 352 as a source of soil microbes. 353 From a statistical perspective, simple random samples are more representative of an 354 area than judgement samples as each sample has an equal opportunity to be selected. A 355 common technique for collecting simple random samples is to establish a grid consisting 356 of two sets of parallel lines at right angles to each other. Each line is assigned a unique 357 number. Pairs of numbers are drawn from a random number table and used to establish 358 intersecting points that denote where a sample will be collected. This process is repeated 359 until the number of required samples is reached. Another simple random sample method 360 is to use a pair of random numbers to designate a distance and angle from a selected 361 starting point. 362 343 344 345 8.4 Sample Types and Practices Prior to using a soil for detector or assay testing, it is important to consider

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