Cottongrowers Greg Jensen from Emerald, Brian Goldsmith from Collarenebri and Rob Collins from Hillston discuss their experiences with 15" cotton during the last few seasons.

Greg Jensen, Emerald

You conducted a trial on your farm this year with 15 inch cotton with the variety Sicot 71BR. How did it go?

I was very happy with the 15 inch row cotton. It was probably about ½ bale/acre better than my next best paddock. It averaged around about 4¾bales/ac. It didn’t receive any different treatment than the other BR fields except for one extra water. So, all in all, it was very good.

As far as season length goes, was it similar to the other BRs?

Yes, I thought it would have come in a bit earlier but it wasn’t that much earlier. We did have to wait for a special picker to come, but effectively that didn’t delay it that much.

From a management point of view, what are some of the advantages you see possibly with the system and any disadvantages?

The advantages of it, is that it closes in extremely quickly. Therefore the weed problems are just about negated. Obviously it has to be Roundup Ready. We do have to control it with Pix because it can get away quickly in the North here.

It does take another irrigation but I think that’s more than made up for in the yields. But everything else including the quality, is the same.

Another thing that is very positive about it is basically you run one set of Alabama’s through it and that’s the only time a tractor runs over it except for a spray rig.

Did you see any disadvantages at all with it compared with your normal system?

Yes, I think the harvesting is a potential problem - we had a dry pick this year so no problems. That’s really it. There were no agronomic problems or anything like that. I think we managed the irrigation pretty well. As for next year, I probably won’t be doing it because we don’t have much water but I think that I will probably look at 30 inch space rows. That is a bit of a compromise between the 15’s and the conventional row spacings and it will negate the worry about the picking and still provide the potential yield that we can get out of it.

Brian Goldsmith, Manager, ‘Collymongle’, part of the Twynam Group.

Brian you have been working with 15 inch now for a couple of seasons. Why did you first get into it?

We first played around with UNR and that forced us to use strippers. We got to the point we were getting a good crop but we could never get it harvested. The inception of the John Deere 15inch cutting heads meant that we could still go with narrow row configuration but actually pick it.

So we leapt at that and we have done three seasons of 15 inch. The main reason we got into the narrow row configuration and the 15 inch was that we see these configurations getting a higher light interception early on with quicker row closure. You have got more plants out there, you have got less sunlight that is hitting the ground and that’s allowing us to get more growth and higher production from any given area.

What do you see as some of the advantages and disadvantages of growing 15 inch cotton?

The 15 inch configuration suits Collymongle as we have a farm that is laid out in kilometre runs. Across the industry if you were laying a farm out today, you certainly wouldn’t do it in kilometre runs. One of the advantages we are seeing is because we have got four rows on a two metre bed we never waterlog the middle rows which is something that was an issue with one metre beds.

There is always some country that is not waterlogged, and if you do get some waterlogging, you will tend to drag it out. The two middle rows will drag the other two rows out and effectively we are not seeing the issues with waterlogging that we have had in the past. We haven’t struck a lot of disadvantages.

We haven’t had any great issues with machinery or picking. Picking was possibly a little slower as we tend to find the cutter heads don’t like the higher moistures. You can’t push the heads as late into a night. But that stems back to picking capacity.

In this coming season what are your plans? Would you change anything this year in regards to your 15 inch?

Everything we grew this year was in 15 inch and this coming season we will look carefully at some trials that we have run and the ginning result as they come back. At this point in time I will probably water run more fertiliser and probably push the nutrition a little bit further, but basically we will keep going on the track we are going.

Robert Collins, discussing UNR and 15 inch cotton. Robert is the Manager or Merrowie Station at Hillston.

Could you give us your history with growing UNR and 15 inch and why you decided to get into it.

We started with UNR or 10 inch row configuration, 6 rows across the top of a two metre bed. The main reason we went there was looking to shorten the crop development time. We have a fairly limited and pretty defined growing season here on the Lachlan and Murrumbidgee.

That’s why we were there, to look to see if we could grow a good mature crop, with less bolls on each individual plant, a shorter stature plant. We were really looking to get maturity within the limited period that we had.

You started with the UNR system and recently moved over to the 15 inch system. What were your reasons for changing? 

Mainly harvest. As far as production goes we were very happy with the 10 inch system. It’s a crop that you can manipulate the architecture quite well, but the limitation was in harvesting using the finger pickup fronts through the strippers. As soon as it was wet or any problem like that, bark became an issue.

It was harvesting that moved us there, and with John Deere developing the 15 inch harvesting set up, that’s been a good tool for us. It will let us grow the crops a little bit bigger, and we don’t have to worry as much about branching as we use to with the comb front.

Branching was a huge issue, but with being able to use spindles now, it is no longer an issue. We are now tending to try and grow the crop out that bit bigger and going for yield again which is a temptation in these dry years. Wet ones will come again but at least with the spindle picking we can harvest without the quality discounts we got when we had the finger type picker.

You mentioned shortening up the season, and the possibility of growing a crop in a little bit shorter time. What other advantages do you see with the system?

The main reason we were going there was to try and give us a little more time in a sense that, once we had enough positions on the crop, we were able to shut it down that little bit earlier and hopefully turn it off. Now we have tended to swing a little more towards yield, not that we were not growing for maximum. We are moving a little away from that, so it’s really now that the technology itself is showing that we have achieved some good yields from it and a good balance of how it uses light.

Row closure here in the Southern areas doesn’t happen every year, so better utilisation of light and better foraging for nutrients are some of the theories that we thought may help us, and so far we have achieved good yields from it. We have got a way to go but we use both 15 inch and the traditional metre row.

That’s mainly to do with how we see our soils’ ability to sub up, how well it moves the water laterally into the middle of the bed. It’s actually one tool that we have found matches very, very well with overhead irrigation. We see those two technologies nurturing and benefiting each other.

Just moving on to disadvantages with the system, you said earlier on that picking used to be a problem with the true UNR system. That’s been alleviated a fair bit now with 15 inch. What are the remaining disadvantages with the narrow row system?

The main ones that we have seen are issues to do with weeds. Cultivation is not a real option. There is some technology out there that’s trying to help on a physical side but we have mainly used Roundup Ready® as a tool to help us. As we see other types of these genetic tools come along, that problem may go away for us too. But at the moment, that would be the main one.

We have had some concerns about how well we are able to get our water into the middle of the beds, that’s a soil selection issue and we use one metre rows if we have got a concern that way. But we have got other properties within our company that are all 15 inch, because the soil type allows that.

There are a couple of questions about nutrition. Is the plant able to cope with the load and the amount of area that they are foraging in? We should be able to sort that out and that’s probably where we will focus most of our interest this year, seeing we are giving the right support in a nutritional way.

What are the key issues that you really have to get right if you are thinking of moving into a 15 inch system?

As with 40 inch, plant uniformity would be the number one. Without the plants there, one the system is not going to work and two we are eventually going to start limiting our yield.

It would come back to being able to get all four rows in the 15 inch configuration, get them all up and get them all uniformly spaced because without that we are not achieving part of the goal which is good spatial distribution of the plants. After that it would be uniformity in irrigation and that’s why I mentioned our soil issues, being able to make sure that the middle rows are getting adequate water.

So far we have seen that we are able to do that and we are pretty happy with it as a technology. It’s going well.

Further Information: John Marshall