Figuring out harvest time
IT HAS turned cool in many areas and as a consequence our mung bean development has slowed down.
This is compared to our March high temperatures when everything was developing at breakneck speed in the mung bean world.
We all know our extra day degrees (or heat units) in summer brings our mung bean crop in a lot quicker than our autumn temperature range.
So right now things have cooled and therefore slowed down, so perhaps our decision-making for desiccation and harvest time should also stretch out more than what we were doing in March.
We invariably say that after a desiccation spray of glyphosate, you can look at harvesting in seven to 10 days time.
After a Reglone spray out you can utilise your zero days withholding period and go as soon as the header and crop is ready.
These general parameters take no account of day degrees or even of residual nitrogen or soil moisture levels.
There are reports from marketers saying they are receiving too many loads of recently-harvested mung beans that have a wrinkled seed coat, where even some of the beans are still soft.
They are advising me that these types of loads may incur $100 per tonne or more in dockage.
Right, before you start ringing me, I realise that mung beans have an indeterminate flowering habit and this season, with dry conditions and then significant rain, they can have black pods, brown pods, light green pods and small dark green pods, plus flowers.
Perhaps our rush to desiccate and then harvest is three to five days too early for both operations.
Staining is another issue and is a result of green or sappy plant parts or weeds ending up in the sample and transferring some of this remaining sap or moisture to your harvested mung seed.
Yes, so when is this plant going to be physiologically mature enough all over to make a desiccation decision?
By the time the last pods make it, the earlier black pods may have spun out and seed is now on the ground.
Hardly ideal for a header to gather them in.
So it is tough, and just to complicate matters even more, parts of the paddock may vary between easy decisions and hard decisions.
So what is the best plan between agros and farmers? The desiccation angle first. You still need to spend some paddock time to ascertain physiological maturity of your pods.
You know, the old plan of splitting open the pod gently and turning it upside down and if all seeds fall out, then that pod, no matter what colour it looks from the outside, is PM.
The unevenness of this
current maturity process is the killer and there is no easy formula for hurrying up those desirable pods.
We are still looking for 90% maturity levels. Levels lower than that and you are really hoping that the pre-harvest spray of glyphosate stops development of those later pods, which then turn rubbery and get thrown out the back of the header.
That is where header set-up is very much down to experience of the operator.
So first desiccation done with glyphosate, plus or minus Ally, and then do you harvest in less than a fortnight’s time? Maybe!
Or do you possibly quicken and improve that desiccation process with a system like double knock and apply Reglone five to 10 days after the glyphosate spray?
Seems I have asked a lot of questions in this article, however I cannot view every paddock of mung beans from the Gulf to the Riverina, so I
put out these ideas to have you consider options and make the best sense you can of a difficult process this year.
I then suggest trying a small area with your header and getting a good representative sample to your favourite marketer and ask his opinion.
He is the bloke that matters when it comes to quality decisions and dollars offered.
Many of these folk have had years and years of mung bean exporting experience and the discussion is well worthwhile.