-5-


Rainfall and temperature data: Accumulated rainfall and average maximum and
 minimum temperature values for the general area are.
 given for the period indicated.

 Time after Accum. Average temperature 0F.
 application rainfall Max. Min.

 1 week 0.00 in 87 61
 2 0.16 87 62
 4 2.16 80 57
 6 '4.35 86 58
 8 5.14 88 59
 10 5.20 89 62


 Method of evaluation: Periodic ratings of sugarcane stand and growth and of
 annual grass and broadleaf weed control compared the
 treatments with the unsprayed controls on a 1 9 rating scale. The rating
 values have been converted to their corresponding percentages of the best
 treatment for this report.

 Experimental results: Emerged weed seedlings and 'cane shoots were killed
 without apparent residual effect on unemerged sugarcane
 or weeds by paraquat ( lb. cation/A) applied before initiation of this
 experiment.

 Many of the herbicides visibly affected sugarcane stand and/or tolerance
 (Table 2). Most of these chemicals provided acceptable to excellent annual
 grass and broadleaf weed control (Table 2). Relatively few herbicides cou-
 pled good annual weed control with good 'cane tolerance (Table 3).

 At 6 and at 10 weeks after application the better herbicidal treatments
 included: fenac, diuron, and several triazines (Table 3). Encap petroleum
 mulch applied on-top-of atrazine, diuron and fenac apparently improved 'cane
 stand and tolerance. Herbicidal activity of diuron against annual weeds
 appeared to be reduced slightly by Encap. Activity of the 3 herbicides
 against bermudagrass was lowered by Encap.

 Paraquat was applied with shielded equipment in postemergence sprays
directed to the base of the 'cane plants at 3 months after initiation to
control emerged weeds. All plots received the same application regardless
of degree of weed infestation.,

 At 6 months after herbicide application the best sugarcane growthlwas
observed in the following treatments: amiben, fenac, diuron, atrazine, pro- *
pazine, simazine and norea.