Moderated release aquatic herbicide formulations
View Patent ↗Described are preferred solid herbicidal formulations that include one or more herbicides in combination with a solid carrier, as well as methods of manufacture and use thereof. Solid herbicidal formulations are designed to deliver a moderated release of the incorporated load of herbicidal agent(s), for example to enhance uptake by target plants and/or the ability to spatially control a plant population within a body of water that exhibits flow.
1. A method for controlling a submersed aquatic weed in a water body, comprising:
applying to the bottom of the water body a granular aquatic herbicide comprising a particulate carrier incorporating one or more systemic herbicidal agents, wherein the granular aquatic herbicide releases less than about 70% by weight of the one or more systemic herbicidal agents within 24 hours after said applying and at least about 90% by weight of the one or more systemic herbicidal agents within 288 hours after said applying, wherein said particles of the particulate carrier have a polymeric layer effective to retard release of the one or more systemic herbicidal agents from the particles, wherein said particles of the particulate carrier have a density greater than water, and wherein the one or more systemic herbicidal agents are exposed to and taken up by roots of the submersed aquatic weed, and then translocated to aboveground tissue of the submersed aquatic weed.
2. The method of claim 1 , wherein the granular aquatic herbicide further exhibits the following release profile for the herbicidal agent(s) after said applying:
Total Weight % Of Original
Herbicidal agent(s) Released
([total weight of released
herbicidal agent(s) at indicated
time point divided by total
original weight of herbicidal
Time after Applying
agent(s)] multiplied by 100)
4
hours
10% to less than 30%
1
Day
20% to less than 70%
3
Days
50% to 100%.
3. The method of claim 1 , wherein the herbicidal agent(s) include triclopyr and/or 2,4-d.
4. The method of claim 1 , wherein the herbicidal agent(s) include triclopyr.
5. The method of claim 1 , wherein the herbicidal agent(s) include 2,4-d.
6. The method of claim 4 , wherein the triclopyr comprises an amine salt form of triclopyr.
7. The method of claim 5 , wherein the 2,4-d comprises an amine salt form of 2,4-d.
8. The method of claim 1 , wherein the herbicidal agent(s) include triclopyr or 2,4-d.
9. The method of claim 8 , wherein the polymeric layer comprises an acrylic latex polymer.
10. The method of claim 8 , wherein the particles comprise agglomerated granules including plant fiber and mineral filler.
11. The method of claim 8 , wherein, but for the polymeric layer, the particles would release at least 50% of the incorporated herbicide(s) within 4 hours after said applying.
12. The method of claim 1 , wherein at least one said one or more herbicidal agent is present in an amount of at least 10% by weight of said granular aquatic herbicide.
13. A method according to claim 1 , wherein the granular aquatic herbicide comprises at least one auxin mimic herbicidal agent or at least one ALS inhibitor herbicidal agent.
14. A method according to claim 13 , wherein the aquatic weed is watermilfoil or hydrilla.
15. A method according to claim 14 wherein the one or more systemic herbicidal agents include at least one auxin mimic herbicidal agent taken up by roots of the aquatic weeds or at least one ALS inhibitor herbicidal agent taken up by roots of the aquatic weeds, and wherein the solid particulate carrier comprises mineral-containing particles.
16. The method according to claim 1 , wherein the granular aquatic herbicide comprises at least one said one or more systemic herbicide of penoxsulam, imazamox, bispyribac, and bensulfuron methyl.
17. The method of claim 1 , wherein the one or more herbicidal agents includes an ALS herbicidal agent present in an amount of about 0.5% to about 10% by weight of said composition.
18. A solid herbicide composition useful for controlling submersed aquatic weeds, comprising:
a solid particulate carrier; and
one or more systemic herbicidal agents;
wherein the solid herbicide composition is effective in the release of less than about 70% by weight of the one or more herbicidal agents within 24 hours, and at least about 90% by weight of the one or more systemic herbicidal agents within 288 hours, upon continuous immersion in static distilled water at 25° C.;
wherein particles of the particulate carrier have a polymeric layer effective to retard release of the one or more systemic herbicidal agents from the particles; and
wherein the particles of the particulate carrier are sink when applied to an aquatic environment exposing the one or more systemic herbicidal agents to roots of the submersed aquatic weeds which are taken up by the roots of the aquatic weeds and then translated to aboveground tissue of the aquatic weeds.
19. The composition of claim 18 , which exhibits the following release profile for the herbicidal agent(s) upon continuous immersion in static distilled water at 25° C.:
Total Weight % Of Original
Herbicidal agent(s) Released
([total weight of released
herbicidal agent(s) at indicated
time point divided by total
original weight of herbicide(s)]
Time after Immersion
multiplied by 100)
4
hours
10% to less than 30%
1
Day
20% to less than 70%
3
Days
50% to 100%.
20. The composition of claim 18 , wherein the herbicidal agent(s) include triclopyr and/or 2,4-d.
21. The composition of claim 18 , wherein the herbicidal agent(s) include a triclopyr agent.
22. The composition of claim 18 , wherein the herbicidal agent(s) include a 2,4-d agent.
23. The composition of claim 16 , wherein the triclopyr agent comprises an amine salt form of triclopyr.
24. The composition of claim 22 , wherein the 2,4-d agent comprises an amine salt form of 2,4-d.
25. The composition of claim 18 , wherein the particles comprise mineral-containing granules coated with the polymeric layer.
26. The composition of claim 25 , wherein the polymeric layer comprises an acrylic latex polymer.
27. The composition of claim 25 , wherein the mineral-containing granules comprise agglomerated granules including plant fiber and mineral filler.
28. The composition of claim 25 , wherein, but for the polymeric layer, the granules would release at least 50% of the incorporated herbicide(s) within 4 hours upon continuous immersion in static distilled water at 25° C.
29. The composition of claim 18 , wherein at least one said one or more herbicidal agent is present in an amount of at least 10% by weight of said solid herbicide composition.
30. A composition according to claim 18 , wherein the solid aquatic herbicide comprises at least one auxin mimic herbicidal agent.
31. The composition of claim 18 , wherein the at least one said one or more herbicidal agent includes an ALS herbicidal agent present in an amount of about 0.5% to about 10% by weight of said solid herbicide composition.
32. The composition according to claim 18 , wherein the one or more systemic herbicidal agents comprise at least one of penoxsulam, imazamox, bispyribac, and bensulfuron methyl.
33. A solid herbicide composition useful for controlling submersed aquatic weeds, comprising:
a particulate carrier comprising mineral-containing particles;
one or more systemic herbicidal agents incorporated in said mineral-containing particles;
said mineral-containing particles having a polymeric coating effective in the retard release of the systemic herbicidal agent(s) from the particles;
wherein the composition is effective to release of less than about 70% by weight of the one or more herbicidal agents within 24 hours upon continuous immersion in static distilled water at 25° C.; and
wherein the mineral-containing particles are sink when applied to an aquatic environment, exposing the one or more systemic herbicidal agents to roots of the weeds which are taken up by the roots of the aquatic weeds and then tracslated to aboveground tissue of the weeds.
34. The composition of claim 33 , wherein said polymeric coating comprises a latex polymer coating.
35. The composition of claim 33 , wherein the one or more herbicidal agents include a triclopyr agent.
36. The composition of claim 33 , wherein the one or more herbicidal agents include a 2,4-d agent.
37. The composition of claim 33 , wherein the one or more systemic herbicidal agents includes an auxin mimic herbicidal agent.
38. The composition of claim 33 , wherein the composition is effective to release least about 90% by weight of the one or more herbicidal agents within 288 hours upon continuous immersion in static distilled water at 25° C.
39. The composition of claim 33 , which exhibits the following release profile for the one or more herbicidal agents upon continuous immersion in static distilled water at 25° C.:
Total Weight % Of Original
Herbicidal agent(s) Released
([total weight of released
herbicide(s) at indicated time
point divided by total original
weight of herbicide(s)] multiplied
Time after Immersion
by 100)
4
hours
10% to less than 30%
1
Day
20% to less than 70%
3
Days
50% to 100%.
40. The composition of claim 33 , wherein, but for the polymeric coating, the granules would release at least 50% of the incorporated herbicide(s) within 4 hours upon continuous immersion in static distilled water at 25° C.
41. A method for making a solid herbicide composition useful in the control of aquatic weeds, comprising:
incorporating one or more systemic herbicidal agents in a solid particulate carrier; and
coating particles of said carrier with a polymeric coating that retards release of the one or more herbicidal agents from the carrier so as to prepare a particulate solid herbicide composition that is effective to release less than about 70% by weight of the one or more herbicidal agents within 24 hours upon continuous immersion in static distilled water at 25° C., wherein particles of the particulate solid herbicidal composition are sink when applied to an aquatic environment, exposing the one or more systemic herbicidal agents to roots of the weeds which are taken up by the roots of the aquatic weeds and then translated to aboveground tissue of the weeds.