Addendum 11-8-2-11-8-2-A-U - Procedure for Manually Sampling Row CropsRules 2,5
A. Corn 1. Randomly select locations to determine sample adequacy. Follow Addendum A and Addendum H instructions. The initial number of samples to take for corn are as follows: | size of area (acres) | # samples |
| 1 - 39 | 8 |
| 40 - 279 | 12 |
| 280 - 639 | 16 |
| 640 or more | 28 |
2. Determine the row width and select the length of row to measure 1/1000th of an acre. | row width (inches) | length of row per 1/1,000 acre |
| 10 | 52 feet 3 inches |
| 20 | 26 feet 2 inches |
| 30 | 17 feet 5 inches |
| 36 | 14 feet 6 inches |
| 38 | 13 feet 9 inches |
| 40 | 13 feet 1 inch |
3. Locate the sample site adjacent to the closest corn stalk.4. Measure and mark the required row length.5. Determine the 3rd and 4th ears of the row and tag these ears with a rubber band. If there are less than four ears in the first row, the last ear and next to the last ear should be tagged. In case where a stalk has more than one ear, count the top ear first. (note: An ear of corn is defined as a cob having at least one kernel. The tagged ears will be used to determine the moisture content, and at least 250 grams of grain are needed. If it does not appear that the 3rd and 4th ears will supply 250 grams of grain for a moisture test, then the 5th, 6th, and or 7th ear should be included until at least 250 grams of corn is collected.6. Husk all ears in the measured length of row and snap the shank off as cleanly as possible. Be sure to include the ears tagged for moisture sampling.7. Weigh the husked ears using a balance scale to obtain a field weight.8. After weighing, put the ears tagged for moisture testing into polyethylene bags and seal. Mark the bags by sample and field number.9. Repeat steps 3 through 8 for each sampling point.10. All the ears saved for calculating moisture shall be brought to the nearest commercial certified grain handling facility to determine moisture content and bushel weight. Obtain a scale ticket signed by an individual certified to run these tests verifying the moisture and weight per bushel.11. Calculate the yield per acre for each sample using this formula: a x b x c x d divided by e = yield per acre
where:
a = weight of all ears/sample
b = 1,000 (portion of an acre represented)
c = ear corn to shell corn factor
d = moisture adjustment factor
e = tested sample weight per bushel
An example for figuring the moisture as described in Addendum R is as follows:
adj. factor = 100 - m / 100 - a
where: m = moisture content of grain at harvest
a = adjusted moisture, example 15.5% for corn
12. Total all adjusted yields and figure an average yield.13. Use the same above procedure when figuring yields from the reference plots, adjust the productivity based on differing soils series as per Addendum Q, and compare the yields to the test plots.B. Soybeans Soybean yield estimates are most accurate within three weeks of maturity.
1. Determine the number of feet of row needed to make 1/1000 of an acre from the following table. This will be a sample area. | row width (in.) | length of single row =1/1000 ac. | row width (in.) | length of single row =1/1000 ac. |
| 6 | 87 ft 1 in | 28 | 18 ft 8 in |
| 7 | 74 ft 8 in | 30 | 17 ft 5 in |
| 8 | 65 ft 4 in | 32 | 16 ft 4 in |
| 10 | 52 ft 3 in | 36 | 14 ft 6 in |
| 15 | 34 ft 10 in | 38 | 13 ft 9 in |
| 20 | 26 ft 2 in | 40 | 13 ft 1 in |
2. Count the number of plants in at least ten different randomly selected sample areas and calculate the average. See Addendum A. average = _____ = a
3. Count the number of pods per plant on ten randomly selected plants from each sample area. Divide the total plants by ten and skip that many plants to count after you count the first plant. Calculate the average. average = _____ = b
4. Calculate pods/acre by multiplying plant population by pods/plant. a x b = _____ = c
5. Calculate seeds/acre by multiplying pods per acre by an estimate of 2.5 seeds/pod. 2.5 x c = _____ = d 6. Calculate pounds/acre by dividing seeds/acre by an estimate of 2500 seeds/pound. d / 2500 = _____ = e
7. Estimate yield by dividing pounds/acre by 60 pounds per bushel. e / 60 = _____ = yield
8. Use the sample adequacy formula, Addendum H, to determine the number of samples to take.9. Total all the samples and average to determine the yield from the test plot. Conduct the testing on the reference crop by using this same procedure, adjust the productivity based on differing soils series as per Addendum Q, and compare the yields.10. If county average target yields are used for the standard, your average yield must be reduced by the state wide harvest loss factor for that year.C. Grain Sorghum 1. Determine the number of heads per acre. Count the number of heads in 100 ft. of row, then calculate: Click Here To View Image
2. Determine the number of kernels per head. This is a two step process for a) estimating the average number of spikelets per head, and b) estimating the number of kernels per spikelet. a. Collect 10 heads from the 100 ft. sample area. Count the number of spikelets (branches from the main rachis) on each head. Total the number of spikelets counted. total number of spikelets / 10 heads = number of spikelets per head
b. Collect 9 spikelets from a "typical head; 3 from the top, middle and bottom portions of the head. Count the number of kernels in each spikelet. Total the number of kernels counted. total number of kernels / 9 spikelets = number of kernels per spikelet
The estimated number of kernels per head can be calculated:
number of spikelets x number of kernels = number of kernels per head
3. Calculate the number of kernels per acre using the results of steps 1 and 2. Number of heads/ac x number of kernels/head = number of kernels/acre
4. Determine estimated yield. Sorghum averages approximately 15,000 seeds per pound. Dividing the number of estimated kernels per acre by the approximate number of seeds per pound will estimate the number of pounds per acre. number of kernels per acre / 15,000 kernels per pound = number of pounds/acre
5. Divide the total pounds per acre by 56 to obtain the bushels per acre.6. The reference plot shall be measured using this same procedure, adjust the productivity based on differing soils series as per Addendum Q, and compare the yields.7. The number of kernels per pound will vary due to growing conditions and hybrid. It is not unusual to have sorghum vary from 12,000 to 18,000 seeds per pound. In estimating grain sorghum yields, it is suggested that a range of kernels per pound values be used to get an idea of the estimated high, low, and average yields for a particular situation.8. Use the sample adequacy formula, Addendum H, to determine the number of samples needed to measure productivity.D. Cotton1. Determine the number of bolls per acre. Count the number of bolls per Sample Row, based on row spacing, then calculate: | row width | sample row length |
| 40" | 13'1" |
| 38" | 13'8" |
| 36" | 14'2" |
| 32" | 16'4" |
For 40" row spacing use: (Number of bolls per 13'1") (1000)= Total number of bolls per acre
Repeat this method four times and average the results.
2. Determine the number of bolls needed to produce one pound of seedcotton. Find the average boll weight in grams and convert to pounds. Calculate: 454 grams/pound / average weight/boll = number of bolls needed to produce one pound of cotton.
3. Determine the number of pounds of lint needed to produce one bale of cotton. a. Only 35% of seedcotton (cotton newly picked) is considered lint.b. It takes 480 pounds of lint to make one bale of cotton. calculate: 480 pounds of lint/bale = pounds of seedcotton to make one bale of cotton 35% seedcotton
4. Determine the number of bolls per plant needed to produce one bale of seedcotton. calculate: (number of bolls per pound of seedcotton)(pounds of seedcotton per bale) = Total number of plants per acre
Number of bolls per plant needed to produce one bale of seedcotton per acre.
Miss. Code. tit. 11, pt. 8, ch. 2, app 11-8-2-A, 11-8-2-11-8-2-A-U