LaMotte Greenhouse Soil Testing Outfit GS-02 User Manual
Page 5
PHOS PHO RUS
QUAN TITY
CON TENTS
CODE
60 mL
*VM Phosphate Reagent
*4410-H
30 mL
*Reducing Reagent
*6405-G
2
Pipets, 1.0 mL, plastic
0354
1
Pipet, plain
0352
3
Test tubes, 5 mL, glass, w/caps
0230
1
Phosphorus Comparator
5274
*WARNING:
Reagents marked with a * are considered hazardous substances.
Material Safety Data Sheets (MSDS) are supplied for these reagents. For your
safety, read label and accompanying MSDS before using.
PRO CE DURE
1.
Use a 1 mL pipet (0354) to add 1 mL of soil extract to a test tube
(0230). Dilute to 5 mL mark with deionized water.
2.
Use a second 1 mL pipet (0354) to add 1 mL of *VM Phosphate
Reagent (4410). Cap and mix. Wait 5 minutes.
3.
Use the plain pipet (0352) to add 3 drops of *Reducing Reagent
(6405). Cap and invert to thoroughly mix contents.
4.
Inset test tube into the Phosphorus Comparator (5274). Match
sample color to a color standard. Record as ppm Phosphorus.
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PRE PARING THE SOIL EX TRACT
A single soil extract is used for all the tests. Between 17 and 18 mL of soil
extract are needed to complete the series of tests. Because of the variable
nature of greenhouse mixes, it is not always possible to obtain the required
amount of extract from a single extraction. Therefore, it is recommended
that the operator carry out the extraction in duplicate until it has been
determined that a single extraction will provide a sufficient amount of
extract.
NOTE:
The Demineralizer Bottle (1115) will be the source of all
deionized water for these procedures. Read the Demineralizer Bottle
Instructions before proceeding.
1.
Remove plunger from 50 mL syringe (0943).
2.
Place filter paper on disc (0947) in the barrel of syringe, centering it
over the discharge hole. Moisten paper with a few drops of deionized
water.
3.
Cover the discharge tip of the syringe with a black rubber bulb.
4.
Fill the syringe to within 1a“ of the top with well mixed, unscreened
soil sample.
5.
Use the Demineralizer Bottle (1155) to add deionized water to the
soil. Continue adding deionized water a little at a time until the soil is
saturated, and a v“ layer of water is standing on top of the soil.
6.
Place the syringe in foam stand. Wait at least 2 hours for the
extraction to occur.
7.
Place the syringe in the Extraction Stand (1110). Remove the black
rubber bulb from the tip of the syringe.
8.
Place a plastic beaker (0944) under the syringe top. Insert the
plunger, and exerting pressure on the plunger, force the water through
the soil, into the beaker. The extract is now ready to be used in the
tests.
AL TER NA TIVE LAB O RA TORY PRO CE DURE
If laboratory facilities are available, the following procedure may be used
to obtain the soil extract.
1.
Measure 150 to 250 mL of well mixed, but not screened, soil.
2.
Wet soil until saturated. Mix to form a paste. Let sit for at least 2
hours.
3.
Place soil on a piece of dry filter paper in a Buchner funnel. Apply
suction until 10 to 20 mL of extract is collected.
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