Rotary Hoe – Justin Blechinger
The rotary hoe can be used either before the crop has emerged or after. It is effective in killing small weeds by burying and/or uprooting them (Singh, 2012). The rotary hoe only works well when weeds are small and the crop must be big enough to resist the physical abuse (Place and Reberg-Horton, 2014). It is pulled behind the tractor at very high speeds to a depth of 1-2 inches. Research is currently being done by the U of S and Agriculture and Agri-Food Canada to determine its effectiveness in Saskatchewan soils and crops.
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Image linked from http://www.castonline.ilstu.edu/ksmick/150/150equip/150rhoe.jpg
Ideal conditions for a rotary hoe are warm and sunny days with slightly dry soils so when the weeds are uprooted they desiccate quickly and die sooner (Place and Reberg-Horton, 2014).
There are advantages of the rotary hoe including its high speed and machine width allowing for a lot of acres to be done quickly, relatively cheap cost and simple machine so minimal maintenance costs, and high efficacy when done under ideal conditions. Some disadvantages are that it is only effective when weeds are small, doesn’t work well when soils are moist allowing weed to regrow, and cannot be used on all crops on the prairies (canola).
I think this is an interesting new technique to the prairies. I have not seen one of these in action but from what I have learned about the rotary hoe it is definitely something I would consider using if I was to grow an organic field or try something new for weed control. It is a pretty simple unit so they should be a relatively cheap unit to buy. They do not cost a lot to run so I think it would pay for itself pretty fast.
References
Place, G. and Reberg-Horton, C. 2014. Rotary Hoe: A Blind Cultivation Tool for In-Row Weed Control. Available online: http://www.organicgrains.ncsu.edu/publications/Rotary%20Hoe_AG-706.pdf (Accessed on March 11, 2014).