The relative

error of estimation can be computed by the following formula (Cochran 1977): $$ \hatd_\textB = \fracH_\textu – H_\textl 2\frac1\bar\barD_\textts \;100\left( \% \right) $$ (8) Validation of the proposed method To present the proposed method for estimating population density of I. typographus, in 2010, the mean total infestation density of the windfall was estimated https://www.selleckchem.com/products/cilengitide-emd-121974-nsc-707544.html in the Klonowskie Mountain range in an area of about 4,000 ha. The large-area method was applied. 50 sample points were selected on the map with a scale of 1:5,000 using EX 527 mouse SRSWOR. After marking the randomly selected points on the map, they were set in the field. Subsequently, the P. abies tree overturned by the QNZ wind last winter was located in the surroundings of each set point. The found windfalls were distributed at various distances from the set sample points. The maximum distance between the set sample points and found windfalls

was about 200 m. Therefore, the coordinates of each windfall were determined, plotted on the map and checked whether all selected windfalls were distributed randomly. The calculations were performed using the software package Spatial Point Pattern Analysis (SPPA) (Haase 1995). After making sure that all selected windfalls are distributed randomly, in June 2010, bark plates were removed from the 6, 7 or 17th 0.5 m-long stem section in each windfall (counting from the butt-end) and I. typographus galleries and maternal galleries were counted. These three sections were used because in 2008 and 2009, they showed the most significant linear correlations between the number of I. typographus maternal galleries in 0.5 m-long stem sections and the total average density of stem infestation in the whole tree stem (Table 1). Only one section was selected on a given windfall—the one that was best available and easiest to debark. Table 1 Characteristics of the relationships between the numbers of I. typographus maternal galleries in distinguished 0.5 m-long stem section k \( \left( nIt_k \right) \) and the total density of infestation (number

of maternal galleries/m2) of a almost P. abies windfall \( \left( D_\textts \right) \) (see also Eq. 3) Stem section Parameters of linear functions Coefficient of determination Mean relative error of estimation From–to (m) Section no. k a 0k a 1k r k 2 p k sw k (%) 0.0–0.5 1 322.31 1.1348 0.1870 0.064 43.20 0.5–1.0 2 156.02 1.4011 0.4276 0.002 40.74 1.0–1.5 3 102.25 1.5390 0.5293 <0.001 38.32 1.5–2.0 4 112.72 1.5198 0.5707 0.001 34.32 2.0–2.5 5 89.10 1.5069 0.6147 <0.001 36.64 2.5–3.0 6 10.83 1.8472 0.8459 <0.001 20.74 3.0–3.5 7 75.36 1.5540 0.8640 <0.001 18.90 3.5–4.0 8 99.53 1.4672 0.8304 <0.001 22.34 4.0–4.5 9 123.76 1.3088 0.7598 <0.001 28.45 4.5–5.0 10 148.47 1.2901 0.6361 <0.001 31.31 5.0–5.5 11 123.01 1.4461 0.7510 <0.001 32.11 5.5–6.0 12 214.51 1.