# C104: UM


## Mail sol. C104

33.6	g	Sea Salt (Ultramarine Synthetica)	
0.5	g	Tricine	
10	g	Complan	
10	ml	**Stock solution**	
50	ml	**SE2 (Soil Extract 2)**	

1. Make up to 1 litre with deionized water and adjust pH to 7.6 - 7.8 with 1M NaOH or 1M HCl.
When dispensing into small vessels, ensure the complan is thoroughly dispersed. Autoclave at
15 psi for 15 minutes.
2. Note: Complan does not dissolve.


## Stock solution

5.625	g	NaNO3	
0.225	g	Na2HPO4	
0.188	g	K2HPO4	


## SE2 (Soil Extract 2)

x		Soil (air-dried)	
x		Distilled water	

1. Site selection for a good soil is very important and for most purposes a soil from undisturbed
deciduous woodland is best. Sites to avoid are those showing obvious signs of man's activity
and particular care should be taken to avoid areas where fertilizers, crop sprays or other toxic
chemicals may have been used.
2. A rich loam with good crumb structure should be sought. Stones, roots and larger
invertebrates should be removed during an initial sieving through a 1 cm mesh. The sieved
soil should be spread to air dry and handpicked for smaller invertebrates and roots. It should
be turned periodically and picked over again. When dry sieve through a finer mesh (2-4 mm)
and store in an airtight container away from light and heat.
3. Soil is prepared as above. Air-dried soil and twice its volume of supernatant distilled water
are autoclaved together at 15 psi for 2 hours and left to cool. The supernatant is then
decanted and then distributed to containers in volumes suitable for making up batches of
media. The aliquots and their containers are autoclaved for an appropriate length of time
(e.g. 1 litre or less for 15 minutes) and are then kept in a cool place (e.g. a refrigerator) until
required.