Blackgrass

[Luke Cropwalker]

Just sat pondering the dreaded blackgrass while I enjoy a Saturday morning brew. I have been trying to think of the way the weed grows throughout the season and if it has weakness? For the life of me I can't think what this weakness might be to even begin to exploit this as a means of control. Anyone any ideas?

 

[Bury the Trash]

Being an annual is a weakness.

 

[SilliamWhale]

It doesnt have a long dormancy or energy reserves if left on the surface

 

[Brisel]

What does blackgrass like? Wet, cold seedbeds with an uncompetitive crop, September drilling into coarse seedbeds, N fertiliser, winter cropping. Now, turn those against it. Good soil structure & drainage, multiple modes of action chemistry, wider crop rotations, lower soil disturbance, varying drilling dates, competitive crops drilled in narrower rows...

 

[teslacoils]

An extra land drain or two in the low points a big help.

 

[shakerator]

Just sat pondering the dreaded blackgrass while I enjoy a Saturday morning brew. I have been trying to think of the way the weed grows throughout the season and if it has weakness? For the life of me I can't think what this weakness might be to even begin to exploit this as a means of control. Anyone any ideas?

full clay drainage systems at 5m spacing alike a football pitch , at a cost just exceeding the land itself

 

[SilliamWhale]

Isn't the truth of it people aren't prepared to do the steps to minimise it because it's not very palatable.

 

[teslacoils]

Isn't the truth of it people aren't prepared to do the steps to minimise it because it's not very palatable.

Not really. You can farm quite well with a low level of BG without it going crazy.

Big change will come with ELMs, and the loss of crawler and ultimately kerb.

 

[farmerm]

Is its weakness not that if you actually deal with it before you have an established blackgrass problem, you don't have a blackgrass problem? I have pulled a grand total of 3 BG plants this week and I am not expecting to find many more. I have yet to find 1 in a wheat field here, only ever in barley, presumably grass weed herbicides in the wheat are still doing the job on the few if any that emerge in our wheat crops.

 

[Sonoftheheir]

Got out of the sprayer to pick some Rogue barley in a wheat field the other day, just happened to see this in the distance. Not had black grass on there before. Only ever get an odd plant here and there on ours. Some neighbours have plenty though!

 

[teslacoils]

Can't change your soil. Some land will just get it. I don't get poppies, cleavers, or anything much else. No wild oats. Just bkackgrass and a bit of cranesbill. That just how it is. Cost are cut now so if I go continuous spring barley would be fine.

 

[MrNoo]

Seems a lot here that are in a mess went down the hybrid winter barley route, think it was advertised to smother out BG but it never did. We stopped growing WB here instead grow SB, spring cropping (if the land is suitable) seems to get on top of it.
I did have one very bad field which I let out for maize, it was left in such a mess (wheel ruts etc as was very wet when they took it off) it then went into a cover crop for a full year, sheep mowed it off, cultivated, left then spray/drilled ww. Very few BG plants at all, very pleased with it
Locally there are some horrendous fields with it, some have sprayed off sections and others been left, seems the worst I have ever seen it around here

 

[yellow belly]

If you have low enough numbers rogue it out

if not then variation of chemical crops and reduce cultivations to zero or plough properly
the more diverse the rotation the better and the more spring crops

doing the same thing every year risks a build up of black grass
the worst crops for black grass are earlier drilled with high nitrogen

with hind sight we could have kept it out over the last 30 years
kept using Avadex started using flufenacet earlier never relied on antlantis
kept the cows started notill earlier and continued growing spring crops in the 1980s not got into wheat rape rotation

i now have less severe black grass than any time since resistance to ipu hoegrass developed in the 1990s
antlantis stopped it for a year or 2

 

[SilliamWhale]

Not really. You can farm quite well with a low level of BG without it going crazy.

Big change will come with ELMs, and the loss of crawler and ultimately kerb.

So whats the problem then?

 

[ajd132]

I think overall I have about 20 acres which is bad, and manageable levels to completely clean. Considering we were a swamp of BG 5 years ago I am really pleased. I do have one farm which is bad in places but the land owner over rules decisions and makes me do things which I know will make it worse. Cannot win there. But I’m pretty validated that my no till and other management is working pretty well, considering we drilled a good chunk between 18-25th September.
The worst bits on my stuff is directly in front of my house which is frustrating and a good reminder!

 

[teslacoils]

So whats the problem then?

Because it doesn't take much for it to go from small pain to complete nightmare. And the usual factors :

1) late drilling, IE from 23rd October. We've had several years where the number of days drilling after that have been zero.

2) even then, prolonged dry after that means preem less effective.

3) oh, plant into tender ground then get 40mm rain? Yeah that's no good either.

So while the cultural options are all known, if goes wrong you suddenly have a huge mess and the "fix it" choices are three years of spring barley, or at least one bare fallow.

 

[Jack Russell]

We have been at low lols for a good few years now. Last year we had a lot of terrible OSR which has shown now how much BG it let through. My wheat crops have now got levels that I haven’t seen for several years.

 

[RobW]

The worst thing for blackgrass is good crop prices... How many fields this year that ought to be going into spring barley will be going into second (or third!) wheat?

 

[ajd132]

The worst thing for blackgrass is good crop prices... How many fields this year that ought to be going into spring barley will be going into second (or third!) wheat?

Or rape. We have got to be very disciplined. I will only do a second wheat on cleaner bits if conditions 23rd of October are really really good.

 

[teslacoils]

If I get the roguing done, second wheat. If not, osr maybe. If later maybe rent it out for rye before it goes into grass.