Table 2.

Association between seasonal click beetle catches of the field and plant damage in the following years.

Monitoring year	Species	Adult/trap per season	Plant damage	No. of records	Range of damage probability	Mean damage probability	RR (high vs. low)	SE	95% CI	Wald χ–square	P χ–square test
Year 0	A. brevis	≤450 (low)	≤15%	256	0.03–0.17	0.06	11.82	5.73	4.57–30.58	25.95	<0.001
			>15%	10
		>450 (high)	≤15%	5	0.21–0.39	0.3
			>15%	4
	A. sordidus	≤400 (low)	≤15%	109	0.023–0.025	0.024	4.31	4.63	0.53–35.32	1.86	0.173
			>15%	1
		>400 (high)	≤15%	147	0.025–0.046	0.028
			>15%	6
	A. ustulatus (empirical threshold)	≤1,000	≤15%	240	0.02–0.04	0.03	3.15	3.29	0.41–24.31	1.22	0.2703
			>15%	6
		>1,000	≤15%	12	0.04–0.05	0.04
			>15%	1
Year −1	A. brevis	≤210 (low)	≤15%	230	0.02–0.12	0.03	37.61	20.09	13.20-107.15	46.1	<0.001
			>15%	4
		>210 (high)	≤15%	5	0.15–0.99	0.48
			>15%	9
	A. sordidus	≤1,100 (low)	≤15%	169	0.02–0.08	0.04	6.14	3.53	2.0–18.98	9.94	0.002
			>15%	5
		>1,100 (high)	≤15%	28	0.08–0.53	0.18
			>15%	6
	A. ustulatus (empirical threshold)	≤1,000 (low)	≤15%	186	0.022–0.029	0.024	3.39	3.67	0.41–28.35	1.27	0.259
			>15%	4
		>1,000 (high)	≤15%	13	0.028–0.044	0.034
			>15%	1
Year −2	A. brevis	≤450 (low)	≤15%	169	0.01–0.22	0.03	40.95	25.39	12.14-38.10	35.83	<0.001
			>15%	3
		>450 (high)	≤15%	2	0.37–0.68	0.52
			>15%	5
	A. sordidus	≤400 (low)	≤15%	83	0.043–0.047	0.046	6.85	7.2	0.87–53.71	3.36	0.067
			>15%	1
		>400 (high)	≤15%	90	0.04–0.08	0.05
			>15%	8
	A. ustulatus (empirical threshold)	≤1,000 (low)	≤15%	191	0.02–0.03	0.02	12.93	13.73	1.61-103.71	5.81	0.016
			>15%	3
		>1,000 (high)	≤15%	4	0.03–0.05	0.04
			>15%	1
Y-1 & Y-2*	A. brevis	other cases (low)	≤15%	74	0.02–0.33	0.05	25.67	—	8.46–77.83	38.94	<0.001
			>15%	3
		>450 & >210 (high)	≤15%	5	—	0.84
			>15%	0
	A. sordidus	other cases (low)	≤15%	46	0.02–0.11	0.07	9.07	5.75	2.62–31.43	12.1	<0.001
			>15%	3
		>400 & >1,100 (high)	≤15%	4	0.13–0.68	0.33
			>15%	5
	A. ustulatus	other cases (low)	≤15%	8	0.06–0.10	0.07	18.67	—	6.21–56.13	2.88	0.089
			>15%	2
		>1,000 & >1,000 (high)	≤15%	—	0.12–0.14	0.13
			>15%	1
Year −1	A. brevis & A. sordidus	other cases	≤15%	180	0.01–0.11	0.04	22.14	10.34	8.85–55.34	43.92	<0.001
			>15%	6
		both species exceeded the threshold	≤15%	2	0.11–0.68	0.27
			>15%	5
Year −2	A. brevis & A. sordidus	other cases	≤15%	166	0.02–0.07	0.04	46.94	28.2	14.47-152.35	41.07	<0.001
			>15%	3
		both species exceeded the threshold	≤15%	1	0.07–0.18	0.11
			>15%	5

RR = Relative Risk; SE = Standard Error; CI = Confidence Interval; * thresholds considering years Y-1 and Y-2 at the same time.