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The Understanding Herbicides course is designed primarily as a stand-alone course to give participants a good grounding in the principles of using herbicides to control weeds. It has been designed to prepare participants for working in the herbicide industry within New Zealand, but is also useful for people working in agriculture, horticulture and regional councils who need to control weeds with herbicides as part of their job.
On successful completion a participant should be able to understand herbicides well enough to be able to select the most appropriate compound for any weed situation and obtain maximum effectiveness from that herbicide without causing damage to crop plants.
All successful participants will receive an official certificate of completion and the material will count as 5-credits at 300-level towards a university qualification.
Explanation of various things about the course; introduce participants to various terminology about herbicides in case they know nothing; herbicide mode of action.
Safety testing of herbicides; relative toxicity of herbicides; New Zealand legislation; withholding periods; the GROWSAFE scheme; the 2,4,5-T and glyphosate controversies; herbicide residues in food.
Solutions; emulsions; wettable powders; granules; dusts; surfactants; chemical drift through the air; common and trade names; calculations.
Interception and uptake of foliage-applied herbicides; availability and uptake of soil-applied herbicides; transport of herbicides in the plant; factors affecting these processes; herbicide selectivity.
Adsorption; volatilization; leaching; photochemical degradation; chemical decomposition; microbial decomposition; rates of degradation of herbicides; bioassays; activity of soil-applied herbicides; selectivity of soil-applied herbicides; effects of weather on herbicides.
Conventional spraying equipment; calibration of a sprayer; back-pack sprayers; problems with conventional sprayers; improvements in spraying equipment; wiper applicators.
Characteristics of importance in decision making; broad-spectrum herbicides; translocated knockdown of dicots in grass crops; contact knockdown of dicots in grass crops; selective knockdown of grasses in dicot crops; sulfonylureas; other knockdown herbicides.
Residual herbicides used primarily for non-selective control; herbicides used primarily for depth protection; selective residual herbicides which primarily control dicots; selective residual herbicides which primarily control grasses.
When weeds reduce yields through competition; when weeds exert indirect effects in pasture; when weeds cause other effects difficult to measure; how most weed control decisions are made.
Problems caused by weeds; keeping pastures competitive; discouraging weeds that establish; weed control in new pastures; weed control in established pastures; control of specific problem weeds; clearing scrub weeds; weed control in riparian plantings; weed control in lucerne using management; weed control in lucerne using herbicides.
Obtaining weed control information; cereals; maize and sweet-corn; forage brassicas; fodder beet; peas.
Sexual vs vegetative reproduction; advantage of genetic variability; development of ecotypes; development of herbicide resistance; rate of herbicide resistance development; using herbicide resistance; examples of herbicide resistance problems in New Zealand.
The course is held at Massey University in Palmerston North, and it runs for 3 days (including a test on the final afternoon), with study material sent out to participants several weeks in advance to allow for preparation for the course. The 2020 course had to be cancelled because of Covid-19. The next one will be held in late July 2021.
$1500 + GST (includes study guide, 3 days of lectures, morning and afternoon tea and lunches, venue hire at Massey University)
Participants should arrange their own accommodation in Palmerston North. The course begins 8.30 am Tuesday, but is finished by 3.00 pm Thursday which should allow participants to travel home that day.
Assoc Prof Kerry C Harrington
School of Agriculture and Environment
Private Bag 11-222
Palmerston North 4442
Phone: (06) 350-4926
Registrations for the 2021 course will not open until January 2021. However, if you hit the "register now" button below, you can ask to be sent a reminder about the course next January once registrations do open.
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Last updated on Thursday 09 April 2020