The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Voi. XXXVII. Part B5. Beijing 2008 
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The goal of this study was to investigate how laser scanners and 
laser point data can be exploited in agriculture and precision 
farming. Growth height and ear recognition of cultivated plants 
were investigated using laser scanner data. 
2. STUDY AREA 
2.1 Kotkaniemi test area 
The plot trial was established at the Kotkaniemi Experimental 
Station of Kemira GrowHow Ltd, situated in Southern Finland 
(N 60°21'28" E 24°22T6") about 50 km from Helsinki. Field 
experiments of fertilization and plant protection are made in the 
Experimental Station and its area is 294 ha, from which 90 ha 
of agricultural fields. 
The two-row spring barley cultivar Justina, spring oat cultivar 
Belinda and spring wheat cultivar Picolo were sown in plots of 
12.5 m2 (1.25 m x 10 m) on 6th May 2006. Justina is a medium 
late barley cultivar, which is mainly used as raw material of 
feed. Belinda is a late oat cultivar and used both for feed and 
food supplies purposes. Picolo is a medium late wheat cultivar 
which can be used for milling because of its' good quality traits. 
Figure 1. Kotkaniemi Experimental Station of Kemira 
GrowHow Ltd is located in Southern Finland. Cultivars were 
sown in narrow rows. 
Plots were fertilized with NPK compound fertilizer (N-P-K 20- 
3-8) at various rates corresponding to 0, 40, 80, 120 and 160 kg 
of N/ha. Thus, an increase in N application rate resulted also in 
an increase in levels of P and K. 
3. DATA AND METHODS 
3.1 Movable rack for the scanner 
Faro laser scanner was mounted on a movable rack specially 
made for this study. The rack was about 3 meter high and laser 
scanner was fastened upside down to the cross-bar of the rack 
and it scanned the ground beneath it. The rack has four wheels 
and it was easy to move throughout the test plots and it was 
made at the Finnish Geodetic Institute. 
Figure 2. Faro scanner is mounted on the rack. 
3.2 Laser scanning test plots 
Plots with different cultivars and different amounts of fertilizer 
were scanned six times using Faro terrestrial laser scanner 
during the growing season of 2006: 
• 1 st scan -15 th of June 
• 2 nd scan - 21 th of June 
• 3 rd scan - 29 th of June 
• 4 th scan - 6 th of July 
• 5 th scan - 19 th of July 
• 6 th scan - 8 th of August 
Every time, three cultivars (Justina, Belinda and Picolo) with 
five different rates of fertilizer were scanned and altogether 90 
scans were made during growing season 2006. Scans were 
made using !4 resolution and hundreds of laser signals were 
recorded from white signal plates of about 2 dm 2 
Figure 3. Images of 3D point cloud data. Points are colour 
coded according to distance from the sensor (on the left side). 
3.3 Field works other data 
Test plots were signalled using white plastic disks and their 
locations were measured using tachymeter to orientate the data 
scanned at six different times.