Influence of Soybean (Glycine max) Population and Herbicide Program on Palmer Amaranth (Amaranthus palmeri) Control, Soybean Yield, and Economic Return

Table 10

Soybean yield and estimated economic return as influenced by preemergence and postemergence herbicide treatments during 2011 in Fields B13 and C11.^a

Preemergence herbicides^b	Postemergence herbicides^c	Soybean yield		Economic return
		Field B13	Field C11	Field B13	Field C11
		kg ha^−1		$ ha^−1
None	No	720b	1620c	−112b	288c
S-metolachlor	No	930a	3420b	−57ab	1118b
S-metolachlor plus fomesafen	No	1120a	3990a	48a	1415a
None	Yes	940a	3820a	−31ab	1339a
S-metolachlor	Yes	1000a	4070a	−56ab	1408a
S-metolachlor plus fomesafen	Yes	1040a	4200a	−34ab	1471a

^aMeans within a column followed by the same letter are not significantly different according to Fisher’s Protected LSD test at P ≤ 0.05. Data are pooled over herbicide resistance traits and soybean populations.
^bS-metolachlor and S-metolachlor plus fomesafen applied at 1500 and 1200 + 270 g ha⁻¹, respectively.
^cPostemergence herbicides included glufosinate and glyphosate applied to appropriate herbicide-resistant cultivars at 560 and 840 g ha⁻¹, respectively.