Effects of selective cutting and herbicide use in spring barley on seed production of Cirsium arvense

Figures & data

Figure 1. Means and 95% confidence limits of number of shoots in C (control), H1 (early herbicide application), H2 (late herbicide application) and S (Selective cutting) prior to the second treatment (June 2016) and at harvest (September 2016).

Figure 2. Means and 95% confidence limits of decrease in number of shoots (100 × (N_June-N_September)/N_September) (%) from June to September 2016 in C (control), H1 (early herbicide application), H2 (late herbicide application) and S (Selective cutting).

Figure 3. Means and 95% confidence limits of the percentage of shoots which at harvest 2016 had produced seeds in C (control), H1 (early herbicide application), H2 (late herbicide application) and S (Selective cutting).

Figure 4. Relation between the number of seeds per flower receptacle and the proportion of rainy days during a 10-day period prior to sampling (r² = 0.923, P = 0.0388).

Figure 5. Means and 95% confidence limits of total seed weight per flower receptacle (g) in C (control), H1 (early herbicide application), H2 (late herbicide application) and S (Selective cutting).

Table 1. ANOVA results, specifying the effects of treatment, week (sampling time), and the interaction treatment x week on number of seeds (flower receptacle⁻¹), average seed weight (mg seed⁻¹), and total seed weight (g flower receptacle⁻¹) in Cirsium arvense populations.

Dependent variable	Effect	d.f.^a	F-value	P
Number of seeds (flower receptacle^−1)	Treatment	3, 14.1	3.40	0.0476
	Week	3, 26.9	4.44	0.0117
	Treatment × Week	9, 26.7	1.71	0.1348
Average seed weight (mg seed^−1)	Treatment	3, 7.13	7.70	0.0123
	Week	3, 18.3	1.54	0.2374
	Treatment × Week	9, 18.2	3.43	0.0122
Total seed weight (g flower receptacle^−1)	Treatment	3, 19.7	9.03	0.0006
	Week	3, 57	1.93	0.1350
	Treatment × Week	9, 57	1.03	0.4289

^ad.f.: numerator and denominator degrees of freedom using the Satterthwaite method.