December 2009 Diary
All three oilseed rape crops have grown away really well since my last diary instalment. In fact, the crop of Flash has probably developed too well and is now way ahead of where it ideally needs to be.
This crop has produced a full complement of 60 plants/m2 and as such is a little too dense. Ideally we would like to see closer to 40 plants/m2 and we are therefore considering strip spraying with an application of Round-Up. By blocking some of the nozzles on the sprayer we are hoping to take out a one metre strip of the crop for every two metres that remain untreated.
The intention is to reduce plant numbers quite dramatically and to increase light interception to the lower branches. In theory the system should work well, but we'll have to test the sprayer in the workshop first to make sure we can create the necessary spray pattern. If those tests work well we'll treat the crops and see how things progress.
Despite the crop having romped so far ahead, we have been really impressed with Flash this year. It has shown a lot of vigour despite the dry conditions at the beginning of the autumn and has never looked checked. And it never looked short of moisture despite a very dry six weeks post drilling.
In hindsight it is a blessing that we didn't apply an extra application of autumn nitrogen after drilling as the crop has been so adept at finding nutrients that it really didn't need any additional help.
The Cabernet and Excalibur which were sown after the Flash are looking just right for this time of year. Both crops have established at approximately 40 plants/m2 and are of a good size. Unlike the Flash they aren't too far advanced. This is undoubtedly because they went into the ground later than the Flash, but also because they were sown in ploughed land which had probably lost a bit too much moisture.
Our agronomist is telling us that all three crops look really clean and that there is no need to spray for Phoma. It is nice to hear that everything is looking so well, especially considering the fact that we had 3.5 inches of rain at the end of October. Even if we had wanted to spray we would have struggled because the fields are so wet and waterlogged that we wouldn't have been able to travel across them anyway.
To top the season off, where we had applied a graminicide to remove barley volunteers, the rape plants have now grown back and have completely filled in the gaps left by the volunteers. In fact I'd go so far as to say that the crops look almost perfect.
The weeks ahead
Hopefully we'll get a few decent frosts over the coming few weeks and months. A decent cold snap will help to keep the plants in check and prevent too much excessive growth.
Whatever the weather brings, we'll be on the lookout for the plagues of pigeons that hurt so many crops last year. Fortunately we have got very few thin patches around so the pigeons will struggle to find a good site to start their attack. Where they do appear we'll be fast on their heels setting up bangers to move them on before they get too settled in.
Thinking ahead to the spring, we have already started to wonder if we can get away with delaying the spring application of nitrogen. At present it might be possible to delay the application until later in the season when the plants need the nitrogen for pod filling. That all depends on a number of factors such as crop height and how wet the fields are. We'll just have to wait and see what happens and make our plans accordingly.