Soil and Plant Testing Laboratory
573-882-0623

Field crops plant testing

Field crops for which recommendations are given

Recommendations are given for the following crops -- up to 4 crops with associated yields can be selected for each sample. That is for one soil sample submitted you may get recommendations for corn at 80 bu/A, corn at 90 bu/A, corn at 100 bu/A, corn at 110 bu/A OR for one sample you may obtain recommendations for corn at 80 bu/A, soybeans at 40 bu/A, wheat at 40 bu/A, alfalfa at 3 to 7 tons per acre. So you may choose any combination of 4 crops of those crops and yields listed in the table below with the restrictions listed on yield.

Code	Crop	Common yield goals
Forage establishment
1	Alfalfa or alfalfa/grass establishment	0
2	Birdsfoot trefoil/grass establishment	0
3	Clover or clover/grass establishment	0
4	Cool season grass establishment	0
5	Lespedeza/grass establishment	0
6	Overseeding legumes into grass	0
7	Warm season grass establishment	0
10	Alfalfa or alfalfa/grass hay	3 to 7 ton/A
11	Alfalfa or alfalfa/grass pasture	100 to 250 cow days/A
12	Birdsfoot trefoil/grass pasture	100 to 200 cow days/A
13	Bluegrass pasture	100 to 200 cow days/A
14	Bermudagrass hay	2 to 6 tons/A
15	Bermudagrass pasture	100 to 250 cow days/A
16	Clover or clover/grass hay	2 to 5 tons/A
17	Clover or clover/grass pasture	10 to 250 cow days/A
18	Cool season grass hay	2 to 6 tons/A
19	Cool season grass pasture	100 to 250 cow days/A
20	Cool season grass seed/hay or pasture residue	0
21	Cool season grass/stockpile fall growth	0
22	Lespedeza/grass hay	1 to 4 tons/A
23	Lespedeza/grass pasture	100 to 250 cow days/A
24	Sudangrass hay	3 to 5 tons/A
25	Sudangrass pasture	100 to 250 cow days/A
26	Warm season grass hay	2 to 5 tons/A
27	Warm season grass pasture	100 to 250 cow days/A
Row crop and small grains
100	Barley	40 to 80 bu/A
101	Buckwheat	500 to 1000 lbs/A
102	Cotton (lint)	500 to 1500 lbs/A
103	Corn (grain)	80 to 250 bu/A
104	Corn (silage)	10 to 25 tons/A
105	Wheat/Soybean double crop*	30 to 80 bu/A
106	Wheat/Sunflower double crop*	30 to 80 bu/A
107	Wheat/Grain sorghum double crop*	30 to 80 bu/A
108	Wheat/Sorghum silage double crop*	30 to 80 bu/A
109	Oats	50 to 100 bu/A`
110	Popcorn	1500 to 6000 lbs/A
111	Rice	3000 to 7000 lbs/A
112	Rye	30 to 70 bu/A
113	Grain sorghum	4000 to 10000 lbs/A
114	Sorghum silage	12 to 30 tons/A
115	Soybeans	30 to 70 bu/A
116	Sugarbeets	15 to 24 tons/A
117	Sunflowers	1200 to 2500 lbs/A
118	Tobacco	25000 to 4000 lbs/A
119	Wheat	40 to 100 bu/A
201	Southern peas	0
202	Watermelon	0
099	Idle	0

Procedure for sampling selected field crops

Corn

Time to sample

Some time between emergence and silking/pollination. Do not sample after silks have dried.

Plant part to sample

Seedling stage
All above ground portion (20 to 30 plants)
Prior to tasseling
The entire leaf fully developed below the whorl (15 to 25 plants)
Tasseling and shooting to silking
The entire leaf at the ear node (15 to 25 plants)

Soybean

Time to sample

The ideal time is when the first bloom appears. However, if problems appear prior to bloom, a sample can be taken. Do not sample after the first pods begin to fill.

Plant part to sample

Seedling stage
All the above ground portion (20 to 30 plants)
Prior to or during flowering
Two or three fully developed trifoliate leaves at the top of the plant. (20 to 30 plants)

Small grain

Time to sample

Any time before head emerges.

Plant part to sample

Seedling stage
All the above ground portion. (50 to 60 plants)
Prior to heading
Select tissue from upper one third of plant. (50 to 60 plants)

Alfalfa and clovers

Time to sample

Just prior to bloom (1/10 bloom) or at harvest stage.

Plant part to sample

Take top 6 inches of plant or top 1/3 of plant. (40 to 50 plants)

Sorghum

Time to sample

Ideal time is when head is fully emerged but before pollination. Samples may be taken at earlier stage if problem develops.

Plant part to sample

Fully expanded and mature leaves. (15 to 25 plants)

Cotton

Time to sample

Before bolls start to set.

Plant part to sample

The most recently matured leaves. (30 to 40 plants)

Submitting plant samples

The when and how of plant sampling is very dependent on the crop sampled.

Instructions for sampling and submitting samples as specified by the Columbia lab should be followed. See specific instructions on selected field crops, vegetables, and fruit crops. The recommended time to sample is just prior to the beginning of the reproductive stage for many plants. Please check the listings under the selected crops first.

Paired samples
Where a deficiency is suspected, take samples from normal plants in an adjacent area as well as from the affected area. You will be charged the price of only one sample when an abnormal sample is accompanied by a normal sample. Take a soil sample from each area also.
Dusty plants should be avoided
If dust is present, brushing or wiping with a clean damp cloth may be sufficient. If not, rinse briefly with water while the material is still fresh.
Care and handling of sample
Air dry the sample and put in a clean paper bag or envelop and take it to the county extension Center or mail it to the lab located in Columbia.
Sample 25 to 30 plants throughout the area.
Fresh plant tissue should be air dried before sending. After air drying put the sample in a clean paper bag or envelop.
When no specific sampling instructions are give
The general rule of thumb is to sample upper, recently mature leaves. The recommended time to sample is just prior to the beginning of the reproductive stage for many plants.
Completion of the information form
It is essential for the lab to properly interpret the plant analysis.

Where to submit plant samples

Soil samples may be submitted to

County extension centers
(recommended method)
MU Soil and Plant Testing Laboratory

Note
Sample submitted directly to the lab should be accompanied by the sample information form and a check for the amount due payable to MU Soil Testing, unless you have an account with us. If you have an account with us fill in the firm and outlet number and we will bill you at the end of the month.

Only the lab in Columbia performs plant analysis. When submitting a sample to the lab the sample information form should be filled out accurately for the lab to properly interpret the plant analysis. Send the original form with the plant sample(s) and retain a copy for your records.

Plant analysis sample information forms can be picked up at the county extension centers or at the MU Soil and Plant Testing Laboratory free of charge or printed from the Web.
Plant analysis sample information form, RTF

Plant analyses fees

Routine analysis and sample preparation Nitrogen, phosphorus, potassium, calcium and magnesium and drying and grinding	$17
Micro elements with routine analysis Including iron, copper, zinc, and manganese requested with routine analysis	$6 ($1.50 per micro-nutrient)
Analysis package (Routine analysis and sample preparation + micro elements + boron) N, P, K, Ca, Mg, Fe, Cu, Zn, Mn and B	$25
Nitrogen (TKN)	$10
Phosphorus (P)	$5
Potassium (K)	$5
Calcium (Ca)	$4
Magnesium (Mg)	$4
Iron (Fe)	$4
Copper (Cu)	$4
Manganese (Mn)	$4
Zinc (Zn)	$4
Sulfate-S	$6.50
Nitrate-N	$8
Boron (B)	$5
Chloride	$6.50
Sample grinding	$2

10 percent discount on 30 or more samples
A sample preparation fee of $2 per sample will be added to all plant tissues that need to be dried and ground.
Testing fee for a good sample accompanying an abnormal sample will be one-half the regular price.

Turnaround time

Soil sample analysis
1.5 working days after samples are received in the lab
Plant, compost, greenhouse media and water analysis
4 to 5 working days after samples are received in the lab

If samples are mailed allow time to and from the lab. Results of samples submitted through county extension offices are mailed first to the county agronomist or horticulturalist for comments or individualized recommendations. The county then mails the recommendations to the person submitting the sample.

Soil test reports can be e-mailed on request at no charge or faxed for a nominal fee.

Plant test results and interpretations

We use the sufficiency and survey ranges as reported in the Plant Analysis Handbook II by Harry A. Mills and J. Benton Jones, Jr. 1996. MicroMacro Publishing, Athens, Ga.

Updated 7/15/05