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9 MATERIAL
9.1 Sampling and response rate
9.1.1 The quality monitoring of the grain harvest
Viljaseula - Finnish Grain Quality in 2012
The farms covered by the monitoring were selected randomly from the Farm Register
of the Information Centre of the Ministry of Agriculture and Forestry (Tike). Farms with
less than five hectares of cultivated area were not part of the sampling. In 2012 about
1,700 farms were part of the sampling. Samples were sent in from 23 per cent of the
farms selected for the quality monitoring. The scale of the study and the time it takes to
take the samples and to send them have an impact on the response rate. The
distribution of the sizes of the farms and the samples sent in are shown in figure 36.
Every year, farms that have not sent in samples during the preceding four years are
chosen for the sampling. There is however also a small permanent group of farms in
the sampling. The quality monitoring of the grain harvest received 841 samples in
2012.
9.1.2 Quality monitoring of the organic grain harvest
In addition to the usual sampling, requests for samples were sent to about 300 farms
for the purpose of the quality monitoring of organically grown grain. These were
selected regionally from Tike’s register of organic production. Samples were received
from 29 per cent of the farms selected for the quality monitoring. The distribution of the
sizes of the farms and the number of samples sent in are shown in figure 37. We
received 167 samples for the quality monitoring of organic grain.
9.2 Grain samples and form for background information
For the purpose of the monitoring, a total of 5,600 sample bags were sent in July to the
selected farms based on the sampling. The number of sample bags depended on the
size of the farm. The farm sizes were divided into the categories 5–9.9 ha, 10–19.9 ha,
20–29.9 ha, 30–49.9 ha, 50–99.9 ha and farms exceeding 100 ha. Requests for two
samples were sent to the two smallest categories, requests for three samples to the
category in the middle and requests for four samples were sent to the two following.
Farms over 100 hectares received requests for 5 samples. The sizes of the farms in
the distribution of the sampling and that from which samples were received are
presented in figures 32–34. Every request for samples was accompanied by a request
form requiring background information specific to the batch of grain, which supplied us
with valuable information on factors related to the grain production (more detail in
chapter 1.4).
Taking samples is an important factor that affects the reliability of the results. This is
why instructions on how to take the samples were sent to the farmers in the letter to the
growers. It had been requested that the samples would have been sent in by mid-
October, but this was changed to a later date due to the special characteristics of the
growing period. The harvesting period was drawn out very much due to the weather
conditions during the growing period of 2012, and it was therefore decided to still
accept samples in November.
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