I swear I look away from the ground for two seconds and more #RussianKnapweed pops up.

#RussianKnapweed status:

One more round of spraying today now that the weather has cooled off for a day. I found a fully adult patch of it that had been hiding from me and was just barely on this side of when chemical control is most effective.

I continue to go out with my soil knife every day and cut out the small offshoots I'm finding, mostly in areas where it was mowed or sprayed with just weedmaster (2,4D+dicamba)—basically areas where just the top growth was killed or cut.

So far, again anecdotally and with some assumptions about what I'm seeing:

2,4D + Dicamba is the best I've got at killing the #RussianKnapweed top growth.

Chaparral is best for long-term control, but doesn't always control the top growth this year adequately. Seems to do best when combined with 2,4D.

Glyphosate works well on other weeds but is basically useless on the knapweed even if you hit at the right time. You can kill the top growth sometimes but it's almost easier to just hand weed.

I've seen what I suspect is this a few times on #RussianKnapweed if I treat with just dicamba and/or glyphosate, but I don't seem to have that problem with Chaparral.

But for the annuals and even some of the other perennials this isn't an issue. Hit them at the right time and dicamba or glyphosate will work just fine.

Wondering what the difference is.

The challenge of #RussianKnapweed in a single picture.

The one on the top/left is a small knapweed plant… without the entire root. The one on the right is kochia. The kochia's root system doesn't get a lot bigger than that: the only time you find them bigger is on much bigger plants and even then proportionally they don't grow nearly as quickly.

Kochia is an annual. It dies off every year and comes back the next. Knapweed is a perennial that can have a 20+ foot root system.

The battle against the #RussianKnapweed continues. Every time I think I have hit it all I find more. Sometimes it was just something I missed. Sometimes it is new growth.

I've hand-pulled a few of the new growth areas, but there's only so much that can be done there. Most of the rest of it gets sprayed with 2,4-D, Dicamba, and/or Chaparral. Plant at a time.

On the plus side I can see successful galls developing on the plants I put the wasps next to, so hopefully that'll help going forward.

Various #Weeds around #MagpieMeadows:

Dock (broadleaf?), smooth horsetail, mallow, flixweed/tansy mustard (also #RussianKnapweed).

The tansy mustard and I have a temporary truce because it seems to be in active war with the knapweed.

The knapweed is my bane.

The dock presents a tripping hazard and displaces things we want. It also will take over if given half a chance.

The horsetails can stay. The mallow can stay so long as it behaves and doesn't get overly excessive.

But we also need to keep things from going to seed as much as possible (at least with #RussianKnapweed). So while the amount of aminopyralid I use is strictly regulated in amount-per-acre terms I can do highly targeted spraying of plants in areas where I am not broadly treating (which I avoid if at all possible), or use dicamba+2,4-D which have much, much lower soil activity.

Basically what this means is that I need to do four treatment rounds a year, depending on the plant in question.

* Aminopyralids are picolinic acids.They also act like a growth hormone. It's less volatile and hangs around in the soil longer (sometimes a _lot_ longer). Has the distinction of being one of the only things that actually works on #RussianKnapweed with minimal damage to alfalfa.

* Metsulfuron methyl is an amino acid inhibitor. Also active in soil.

These are all selective herbicides that target broadleaf plants with slightly different specialties.

As with most things, the goal is not complete elimination (except for the actual noxious weeds and mostly just #RussianKnapweed for how dangerous it is to horses and due to the county rules), rather it is management.

We're not haying the pasture or anything, so mostly it just has to be safe(r).

I've talked about before the controls we use: a combination of cultural, mechanical, biological, and chemical. It is also a _process_ and I expect it to 1. take years 2. never be truly finished.

* Mowing is taking place now since it is about to bloom. This also gives the grasses more of a chance to fight back.

* Hand pulling in limited areas, mostly around the roses.

* Wasps had four release sites around the property and have cordoned off patches of #RussianKnapweed that won't be sprayed or mowed. Basically giving them a starting point to spread. Should start seeing galls next week.

* I treated some of the bolting knapweed with WeedMaster and it worked better than expected.

Dealing with #RussianKnapweed, progress:

* Spraying the scattered patches now with a combination of Chaparral (aminopyralid+metsulfuron methyl) and 2,4D. This is especially useful in areas where we don't want a lot of bycatch since I can do it with a hand-sprayer.

* Winter treatment over the large areas (the ones that are too big for a hand sprayer or where there is not a mix of alfalfa we want to keep) with chaparral seems to have been successful in several areas. Now to repeat this year.

Oh thank goodness. We're getting biocontrol agents for #RussianKnapweed.

Wasps next week. Midges in June.

Finally.

Not a miracle cure, but a solid step in the right direction.

* _Any_ scorched-earth approach (imazapyr, glyphosate) that is sufficient to kill it will also a) wipe out the grasses b) fail to kill enough of the root to beat it back. Leading to a bigger (or equivalent) outbreak next year. Usable for spot treatments, but only for spot treatments and only if pretty aggressive

* About the only pesticides that seem effective against #RussianKnapweed are the Picolinic acid group: Aminopyralid, Clopyralid, Picloram, Triclopyr

* Preferable to combine controls

* Most of the cover crops you might use to try and give your grass a fighting chance against it are toxic to #horses (but fine for cattle and goats, for whom #RussianKnapweed isn't nearly as much of a problem for).

* Mowing regularly _can_ help but the best you can really do is slow it down and hope that enough things in combination slow it enough for your grasses/other plants to have a fighting chance.

* The roots go so deep that pulling is basically the same as mowing but more time consuming

Dealing with #RussianKnapweed after it has become established is… a challenge.

Some notes:

* It basically laughs at glyphosate (roundup). If you don't use it at exactly the right time it barely seems to notice and even then about the best you can hope for is to scorch the surface, not the root

* AFAICT 2,4-D either doesn't phase it or it actively likes it unless you combine it with something else. Completely ineffective on its own

* Fire helps it by killing competition

#Agriculture #Horses