Joint Research

Starter fertilizers for corn
Dr. Peter Sikkema, University of Guelph, Ridgetown

In 2007 and 2008, 28 and 35 field experiments were conducted, respectively, for a total of 64 experiments over a two-year period. 29 trials were conducted in corn, 22 in soybean and 13 in wheat. Field studies were established in growers’ fields in Chatham-Kent, Elgin, Essex, Huron, Middlesex and Perth counties as well as at the Huron Research Station and the University of Guelph, Ridgetown Campus.

Control strategies were evaluated for the management of the following problem weeds: volunteer adzuki bean, spreading atriplex, wild carrot, common chickweed, cocklebur, crabgrass, dandelion, jimsonweed, prickly lettuce, primrose, giant ragweed, sandbur, annual sowthistle and vetch.

waterhemp control in corn with converge	sandbur control in corn with option	bur cucumber control in corn with pardner + atrazine
waterhemp control in corn with primextra plus callisto	spreading atriplex control in corn with pardner + atrazine	giant ragweed in corn

KEY RESULTS:
Large crabgrass: In beans, Assure II or Venture applied post-emergence provide the best control of crabgrass of the graminicides evaluated.

Long-spined sandbur: Eight experiments have been completed on the control of sandbur in corn. Converge provides the best control of the pre-emergence options available but the control is still only fair. Define, Dual II Magnum, Frontier, KIH-485 and Prowl applied pre-emergence provide poor control of sandbur in corn. Accent and Elim applied post-emergence provide good control of sandbur while Ultim, Impact, Option and Summit provide fair control and Callisto provides poor control.

In soybeans, none of the pre-emergence herbicides (Command, Define, Dual, Frontier, KIH-485) provide commercially acceptable control of long-spined sandbur. Of the post-emergence options, Assure, Excel Super and Venture provide good control while Select and Poast provide fair control.

Volunteer adzuki bean: In soybeans, the pre-emergence application of FirstRate, Lorox, Sencor, flumetsulam or Pursuit provide very poor control of volunteer adzuki bean. Classic, applied post-emergence, provides fair control of volunteer adzuki bean in conventional soybean while Blazer, Reflex, Basagran, Pinnacle, FirstRate, Pursuit and Clean Sweep provide very poor control. Glyphosate, applied post-emergence, provides good control in Roundup Ready soybean.
Spreading atriplex: Pre-plant in soybeans, Roundup provides only fair control of spreading atriplex. Tank mixes of Roundup plus either Sencor, Lorox, Conquest or Boundary provide excellent control of spreading atriplex prior to seeding soybean.

Wild carrot: The post-emergence product of choice in conventional soybean is Classic. In Roundup Ready soybean, glyphosate at 900 and 1,800 gallons per hectare provide 33 and 80 percent control, respectively.

Chickweed, common: Refine Extra and Trophy, applied post-emergence in winter wheat provide excellent control of common chickweed while Infinity provides fair control. 2,4-D, MCPA, Target, Estaprop, Lontrel and Buctril provide poor control of chickweed in winter wheat.

Cocklebur: In corn, BAS 781, BAS 800 and Converge applied pre-emergence provide greater than 75 percent control while atrazine, Banvel, Callisto plus atrazine and Marksman provide less than 75 percent control. Banvel and Marksman applied post-emergence provide excellent control of cocklebur in corn while Distinct, PeakPlus, Summit and Callisto plus atrazine provide good control. Atrazine, Shotgun, Pardner plus atrazine, Impact plus atrazine and Laddok do not provide commercially acceptable control of cocklebur in corn.

In soybeans, FirstRate applied pre-emergence provides excellent full season control of cocklebur while Lorox, Sencor, Pursuit, Command and Python all provide poor control. FirstRate applied post-emergence provides excellent full season control of cocklebur in IP soybean. Classic, Pursuit and Clean Sweep provide fair control and Blazer, Reflex, Basagran and Pinnacle provide poor control.

Dandelion: The post-emergence application of dichlorprop/2,4-D (Dichlorprop D, Estaprop or Turboprop) in the spring provides excellent dandelion control in
winter wheat.

Jimsonweed: In corn, the pre-emergence herbicides containing atrazine (atrazine, Marksman, Converge plus atrazine, Callisto plus atrazine) plus BAS 781 provide excellent control of jimsonweed while Banvel and BAS 800 provide good control.

Prickly lettuce: In winter wheat, the growth regulator herbicides (2,4-D amine, 2,4-D ester, MCPA amine, MCPA ester, Dyvel, Target and Estaprop) all provide good control of prickly lettuce.

Primrose: In winter wheat, 2,4-D, Target, Estaprop, Refine Extra and Trophy provide excellent control of primrose in winter wheat while MCPA and Buctril provide good control. Lontrel and Infinity provide fair control of primrose in winter wheat.

Giant ragweed: In corn, none of the pre-emergence herbicides (atrazine, Banvel, Marksman, Converge plus atrazine, Callisto plus atrazine, BAS 800 and BAS 781) provide commercially acceptable control of giant ragweed. In contrast, all of the post-emergence herbicides (atrazine, Banvel, Distinct, Marksman, Shotgun, Pardner plus atrazine, PeakPlus and Summit) except Callisto plus atrazine provide excellent control of giant ragweed.

In soybeans, FirstRate applied pre-emergence provides good control of giant ragweed while Lorox, Sencor, Command, Python and Pursuit provide poor control. FirstRate, applied post-emergence provides near perfect control of giant ragweed in soybeans, Pursuit provides good control, Clean Sweep provides fair control and Blazer, Reflex, Basagran, Pinnacle and Classic provide poor control of giant ragweed.

In wheat all of the post-emergence herbicides (2,4-D, MCPA, Estaprop, Lontrel, Target, Refine M, Trophy, Infinity) evaluated with the exception of Buctril M provide excellent control of giant ragweed in winter wheat.

Sowthistle, annual: In soybeans, Classic applied post-emergence provides excellent control of annual sowthistle while Blazer, Reflex, Basagran, FirstRate, Pursuit and Clean Sweep provide good control. Pinnacle provides only fair control of annual sowthistle in soybean.

Vetch: Trophy, applied post-emergence in winter wheat, provides excellent control of tufted vetch. Banvel, Dyvel, Target and 2,4-D provide good control, MCPA, Estaprop and Lontrel provide good control and Buctril M and Refine Extra provide poor control of tufted vetch in wheat.