(IPPM) in Vegetables - Vegetableipmasia.org

Resource Manual on IPPM in Rice
World Education Philippines, Inc.
soil sample representing an area of as much as 10 hectares, only a few grams are
used in the actual analysis.
Soil analysis can be done using a simple tool or Soil Test Kit (STK) for qualitative
analysis for soil pH, nitrogen, phosphorus and potassium or by running a complete
chemical analysis in the soil laboratories. Both these tests are tools to help farmers
make decisions on how best to prepare the land to provide what the plants need.
The result of the analysis is only a piece of information used by technologies in
making fertilizer recommendations. This information however, is not sufficient
for the farmers to arrive at an intelligent decision. It should go hand in hand with
field experiments or trials and with proper understanding of the different aspects
of crop production both biotic and abiotic factors.
1. Proper Soil Sampling
The main objective of soil sampling is to collect a small amount of soil sample
weighing about one half kg that will represent the soil in a large area, e.g., one
hectare furrow slice that weighs about 2 million kilogram. Since only a small
amount of soil sample is used in chemical analysis and results are projected for a
large quantity of soil, the accuracy of soil testing depends largely on proper soil
sampling.
The rooting habit of plants must also be considered. For crops with shallow
rooting depth, samples collected from the surface layer (20-30 cm) will suffice.
For deep-rooted crops soil samples must be collected up to the subsoil
(approximately 20-26 cm).
Using the most common farm tools and materials such as shovel or spade, knife or
trowel, small pail and plastic bags, the following are steps on proper soil sampling
technique.
a. Make a map of the Farm showing Sampling Areas (SA).
Divide the farm into sampling areas. Each sampling area should be more or less
uniform in cropping history, past lime and fertilizer treatments, slope degree of
erosion, soil texture, and color. Each SA should not be more than 5 hectares.
b. Collect Spot Soil Samples from each Sampling Area.
In each sampling area dig from 5 to 10 pits and collect sample in each pit. The
number of spot soil samples depends on the size of the sample. A spot sample is
taken in the following manner:
1) Before digging the pit, clear the soil surface of litters and vegetation.
2) Using spade or shovel, dig a pit to a depth of 20-30 cm.
3) From one vertical side of the pit, take a slice of soil 2-3 cm thick with a single
downward thrust of the spade. Using a knife or a trowel, trim the slice of soil
on both sides to a bar 3-4 cm width.
4) Place this bar of soil (representing one spot soil sample) in a pail or any
suitable clean container.
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