in the present invention , the foregoing difficulties are obviated in that there is provided a low cost , easily dispersed formulation consisting of commercially available herbicides . in accordance with the invention , the formulation is initially comprised of three herbicides , dichlobenil -( 2 , 6 - dichlorobensonitrile ), atrazine -( 2 - chloro - 4 ( ethylamino )- 6 -( isopropylamino )- s - triazine , and simazine -( 2 - chloro - 4 , 6 - bis ( ethylamino )- s - triazine . these herbicides can be applied in five different formulations . ( 1 ) dichlobenil 50 wettable powder ( wp ), 5 gl - 1 + tween 80 ( 0 . 5 %), ( 2 ) simazine 80 wettable powder ( wp ), 5 gl - 1 + tween 80 ( 0 . 5 %), ( 3 ) atrazine 80 emulsifiable concentrate ( ec ), 10 gl - 1 + tween 80 ( 0 . 5 %), ( 4 ) simazine + dichlobenil + tween 80 and ( 5 ) atrazine + dichlobenil + tween 80in the same doses of the formulated product . the tween 80 is used as a surfactant and is also a wetting agent . the formulation is sprayed onto the foliage of the host and to the epiphytic weeds . the doses are chosen by a dose response assay and is familiar to those skilled in the art . the formulated mixtures can be dispersed using conventional methods such as knapsack , power and bottle sprayers as well as aircraft sprayers . these mixtures produce a synergistic action and have an increase in the effectiveness of the treatment . during october 1997 to may 1998 in the area of plantation , fla ., the inventor tested these herbicide formulations on ten different host species which were actively growing and were infested with epiphytes of the tillandsia species . the following treatments were applied : atrazine 10 gl - 1 , dichlobenil 5 gl - 1 , simazine 5 gl - 1 , simazine 5 gl - 1 + dichlobenil 5 gl - 1 and atrazine 10 gl - 1 + dichlobenil 5 gl - 1 . tween 80 ( 0 . 5 %) was added to all the formulations . all the selected herbicides , alone or in combination controlled the epiphytes without causing phytotoxicity to their host plant , owing to the different absorption systems of the epiphytes and their hosts . the following example is given as specific illustration of the invention . it should be understood , however , that the invention is not limited to the specific details set forth therein . table 1______________________________________population level of epiphytic species tillandsia recurvata ( number of individuals ) before and after treatments : ( tween 80 was included in the formulations ) oct . nov . dec . feb . mar . april may 20 20 20 20 20 20 20treatment treatment______________________________________control 140 135 133 156 150 150 atrz . & amp ; dich . 140 138 139 1 1 1 simaz . & amp ; dich . 140 136 146 18 18 18 atrazine 140 139 122 115 45 3 simazine 140 140 143 22 2 4 dichlobenil 140 124 117 5 1 1______________________________________ accordingly , the reader will see that a selectivly formulated herbicidal composition of the invention provides that : it will be absorbed by the epiphyte without affecting the host species and causing phytotoxic effects on the terminal buds and leaves of the host plant . it will be safe for humans and wildlife when used at the recommended doses . those skilled in the art will have no difficulty in determining suitable proportions of the above compositions to be used . the invention has been described as applied to preferred embodiments and it will be understood that various substitutions and changes may be effected without departing from the spirit and scope of the novel concepts and principals of this invention .
a herbicidal composition to selectively control undesirable epiphytic weeds by applying active ingredients in an effective amount of atrazine , simazine , dichlobenil , atrazine + dichlobenil , simazine + dichlobenil and the surfactant tween 80 .