John Marshall, CSD Extension and Development agronomist - Dalby, outlines some timely pre planting advice.

John you have some concerns about early planting?

There are many things against trying to establish cotton in the later part of September under the weather conditions a lot of the growing areas frequently experience.

Dr David Nehl’s work has shown that when  the soil temperature falls below 15°C during the 7 days post planting, there is a rapid increase in plant mortality.

Dr Stephen Allen with work on  Fusarium has shown a dramatic increase in Fusarium incidence with early planting.

We know that all growing areas are experiencing an increase in incidence of Black Root Rot, and a cool, unfavourable start certainly increases the incidence of that disease.

You have the repercussions  with you for the rest of the season in some seasons it can have a noticeable effect on yield. In a dry year like this, moving the planting date slightly later increases the chance of getting better supporting rain in-crop, and runoff increasing storage volume in those areas that are  light on.

And I guess at the end of it, looking at a season like this where a lot of the valleys are short of water, we are dealing with low prices, then why take the chance of having to replant? The catch phrase ‘plant early, plant often’ is derived   from a lot of bad experiences.

What conditions are the seed beds in?

That’s one of the very favourable things coming in to this season, even compared with last year. For most valleys it’s been a good winter, with good intermittent rainfall, so the opportunity has been there to get seed beds into good condition. Subbing up should be good and stubble levels are low.

Anything to watch for with watering up?

Looking at what’s happened in the industry, one of  the outstanding features this year is the continuing strong  increase in the percentage of both Roundup Ready® and Bollgard II® stack products.

An increasing number of growers are going to be watering up and for some  of those growers it’s a new experience - they haven’t experienced how quickly weather conditions can change and affect crop establishment when  watering up.

Growers have got to sit on their computers, and watch for and track those fronts coming through, and try and estimate their passage time, and start to keep records to build up confidence in prediction. Picking a time to put the water on, so there is a soil rising temperature phase during germination is critical. 

As far as depth goes, a lot of growers use as a guide that if they walk along where the planter had been through and they see the occasional coloured seed on the surface, that is a pretty good working depth  - going too deep, the potential is there for seed to sink lower, especially if the seedbed is poorly prepared . And I guess  water off as quickly as possible.

This year’s seed quality?

Once again another very favourable thing for the season we are going in - such magnificent conditions at picking last year has ensured that the seed that’s been produced,  right across the board, is extremely good quality. However, we would encourage growers, for their particular seed lot, to get seed quality  information either from their Distributor or go to the CSD web page (Germination - See Front Page). Enter in the variety, treatment and AUSlot number,to get the germ percentage, seed vigour index and seed count for their particular lot.

What planting rate should  growers be using?

Obviously with Bollgard, this is something that growers are still fine tuning and doing their own trialling.

The work that CSD has been doing for six years now has indicated pretty clearly that with Bollgard, there is a potential for slightly higher yields with slightly higher plant stands than what growers have traditionally used with conventional.

So what we would be saying is aim to drop 14-14-15 per metre to get 11 established,  that being based on a 75% final establishment, which is the type of figure that the industry disease surveys over a number of years have  shown to be pretty average across most of the valleys.

Obviously if growers are watering up later on in the season when soil temperatures have warmed up significantly, they will get a higher establishment percentage; that 75% value seems to be pretty close to the mark for most areas at normal planting time.

John, if growers encounter tough conditions at planting, when should they start assessing if the plant stand is good enough?

We always hope that this is something that growers don’t have to worry about that - after about two weeks  or so, ideally they can walk out there and see nice green rows straight along the top of the beds.

But every so often we do strike a combination of wet conditions and plunging temperatures which can cause problems.  Greg Constable has always worked off the principle that it is no sense worrying about assessment until 80 day degrees have elapsed since planting basically.

That’s the period of time it takes to get the establishment process well underway. So bear that in mind. Once you are looking at a stand, I guess gappiness is a pretty important thing that can influence final yield. Another thing  when doing the assessment and plant stand counts  is what else can potentially go out from when you do a count, more disease  additional herbicide damage etc.

If there are establishment problems, or you need seed for late planting  or for top up. What is the position there?

 CSD has a series of depots right through the growing areas throughout the planting season and the main idea of those is to provide the capacity of growers  to top up if they are a couple of bags short, or  if they are unfortunate enough to have to replant particular areas. I guess the whole industry is hoping that more water comes on stream and that the price starts to rise even in the early stage of the season.

There is a good range of varietal choices available to go into the depots  for this late plant scenario, but timely notice needs to be given . As far as seed treatments go, obviously later in the season, not all treatments are available on every variety.

However, a suitable variety x treatment choice can be found for every situation.  There is now an increasingly wider range of maturity choices, so there are  some ideal varieties  for growers if they choose a November planting for instance with a stack variety or a Roundup Ready or straight Bollgard. Remember to match both yield and fibre quality considerations with the time of planting.

Further Information:
Robert Eveleigh, John Marshall,  Craig McDonald, David Kelly or James Quinn