Australia
September 27, 2017

When does a fracas become a melee? When does a cake become a soufflé?

When does a wild radish seed become a viable seed, after which time spraying with a crop topping herbicide becomes futile?

We know that for grass weeds we need to crop top or spray top sometime between flowering and milky dough of the grass seed (depending on the herbicide) to achieve high levels of control, but this timing is not well understood for broadleaf weeds such as wild radish.

In the early 2000’s, Dr Aik Cheam from DAFWA did a great job of describing the critical wild radish pod stages, and then followed up with some crop topping trials to measure the efficacy of herbicides sprayed at the various stages.

You’ll need a long thumbnail or a sharp pocket knife at the ready to get to know what your wild radish seed is up to.  

In a nutshell, if the wild radish seed has a dark green embryo present it is very hard to render this seed unviable with any of the well-known crop topping herbicides.

For diagrams describing the wild radish pod stages and some crop topping data, click read more below.

Read more

Website: http://www.ahri.uwa.edu.au/

Published: September 27, 2017