PRELIMINARY DATA ON PRODUCTIVITY
AND COST OF WOOD ASH SPREADING
IN FOREST
Modris Okmanis
LSFRI Silava
Project No. 2013/0065/2DP/2.1.1.1.0/13/APIA/VIAA/034
Topicality
• Wood ash utilization problems:
– More than 30 000 t of wood ash produced yearly.
– Most of ash is landfilled while there are other
alternative options.
• Suitability for forest fertilization:
– reduce soil acidity,
– increase the effective cation exchange capacity,
mineral saturation and decomposition of organic
matter,
– positively affect the growth of trees,
– Lack of K and P in peatlands.
• Insufficient research done up to now in Latvia.
2
Spreading machinery
3
Spreading trailer
4
Trials
5
Treated Norway spruce stands
Stand
key
Forest type
Age,
years
228-5
Hylocomiosa.
48
209-13
Oxalidosa turf. mel.
48
231-12
Oxalidosa turf. mel.
43
221-17
Hylocomiosa.
48
6
Sheme of operation
7
Composition of wood ash
Nutrient
Content, g kg-1
Dose, kg ha-1
P
5.84
11.68
K
19.64
39.28
Ca
114.11
228.22
Mg
19.36
38.73
Mn
1.62
3.23
8
Time consumption for each object
Average
Average
distance
length of
Stand key
from
spreading,
loading to
m
stand, m
Wood ash Arrival to
loading,
stand
min.
time, min.
Stump
cutting,
min.
Wood ash
spreading,
min.
Drive
out,
min.
Spreading
productivity,
ha h-1
228-5
93
1020
12
204
96
48
46
0.52
209-13
226
150
16
109
82
41
10
0.70
231-12
140
740
7
92
27
14
20
0.38
221-17
72
110
12
97
68
34
14
0.66
9
Share of work elements in total time consumption
10
Improvements required
No side shields needed.
Shorten the drawbar.
Strenghthen frame
mount.
Lift up spreading
mechanism.
Rear axle need to
have with
hydraulic drive.
11
Results
• Treated area 10 ha.
• 20 t of wood ash spread.
• Total time consumed for fertilisation was 17
hours and 29 minutes.
• Costs of wood ash spreading – 437.13 EUR or
43.71 EUR ha-1.
12
Conclusions
• Spreading productivity increases as increase
treated area (lenght of technological corridor).
• In this case wood ash spreading productivity
was 0.57 ha h-1 and costs 43.71 EUR ha-1.
• With trailer improvements even higher results
of ash spreading are expected.
13
The study is done within the scope of
the European development fund project
“Elaboration of methodological and
technical solutions for utilization of
wood ash in forest fertilization”
(2DP/2.1.1.1/13/APIA/VIAA/034).
14
Thank you!
15