- 7 



Those growers who like the quick "knock-down" of weeds with 

 paraquat, but wish to avoid the necessity of a repeat application 

 during the year, could apply a mixture of paraquat pi us simazine o_r 

 diuron. The spray mixture should keep the treated area relatively 

 free of weeds during the growing season. 



Herbicides in Stone Fruit Plantings 



The margin of safety between herbicide tolerance and toxicity 

 is less for stone fruits than for apples. There are several rea- 

 sons for this. Stone fruits are frequently planted on lighter soils 

 with less organic matter content, and organic matter is known to re- 

 duce toxicity of herbicides considerably. Furthermore, they are apt 

 to be cultivated rather than mulched. Mulch is a source of organic 

 matter and consequently adsorbs herbicides. Finally, they are in- 

 herently more susceptible to herbicides than are pome fruits. 



Although the writer has successfully used several herbicides 

 in peach orchards, the exact amount applied was known. In the hands 

 of some applicators, paraquat may be the only safe herbicide to use 

 in peach orchards because of their tendency to apply excessive dos- 

 ages. 



Growers who are currently cultivating their peaches might con- 

 sider the use of an herbicide and the discontinuation of this prac- 

 tice. An herbicide program may be more economical and our studies 

 show that tree performance should be equivalent to that obtained 

 from cultivation. 



D i c h 1 b e n i 1 



dichl 

 this 

 late- 

 a t i 1 e 

 appl i 

 ef f ec 

 have 

 of Ma 

 Weed 

 of th 

 i n Ma 



Growers 

 obenil b 

 h e r b i c i d 

 fall or 



and may 

 ed when 

 ti ve mus 

 found th 

 rch are 

 control 

 e 150-lb 

 rch (Tab 



like 

 ut oc 

 e. T 

 early 

 pers 

 tempe 

 t be 

 at ap 

 as ef 

 rati n 



than 

 le 1) 



the conv 

 c a s i n a 1 

 his is p 

 -wi nter 

 i s t only 

 ratures 

 appl i ed 

 p 1 i c a t i 

 fecti ve 

 g s in 19 



of the 

 . Both 



enien 

 ly th 

 artic 

 appl i 

 a fe 

 are 1 

 in ea 

 ns of 

 as ap 

 68 sh 



100-1 

 rates 



ce of 

 ey des 

 ul arly 

 cation 

 w days 

 ow, th 

 rly sp 

 dichl 

 p 1 i c a t 

 owed , 



b rate 

 i n No 



the 

 ire 



tru 

 s . 



on 

 eref 

 ring 

 oben 

 ions 

 howe 



of 

 vemb 



late- 

 a spr 

 e whe 

 Dichl 

 the s 

 ore , 

 . In 

 i 1 in 



the 

 ver , 

 a p p 1 i 

 er we 



fall app 

 ing appl 

 n early 

 obenil i 

 oil surf 

 appl icat 

 1 imi ted 

 the 3rd 

 previous 

 greater 

 cation n 

 re equal 



1 ica 



icat 



snow 



s hi 



ace 



ions 



tri 



or 



Nov 

 effe 

 f Hi 



ly e 



t i n of 

 ion of 

 s prevent 

 ghly vol - 

 unl ess 

 to be 

 al s , we 

 4th week 

 ember . 

 ctiveness 



chlnhpnil 



f fecti ve. 



Table 1. Effectiveness of November and March applications of 4% 

 granular dichlobenil for the control of weeds. 



Application rate 

 (lbs commercial 

 product) 



Percent weed control mid-August, 1968, result- 



i ng from applications: 



Nov. 1, 1967 Nov. 15, 1967 March 21, 1967 



100 

 150 



88 

 85 



79 



90 



59 

 84 



