General spraying questions?

[Catscratch]

1 - it's said cleth is best sprayed early on young plants... would spraying on regrowth after mowing be effective?

B - it's been hot and dry. Plants aren't growing much. In general it considered best to spray growing plants. We have a cool front with rain forecasted. Temps will drop from low 100's to 80's for a few days. Spray right before the front hits or right after? It's likely the temps will head north of 100 again after the front has passed.

 

[FarmerDan]

1. Its the root system that's the problem. Young plants tend to have top growth larger than the root. They are easy to kill because of this.

Contact herbicides are absorbed by the green part and distributed throughout the plant with the objective to kill the root - or that's the hard part.

An old plant's regrowth is supported by a now much larger root system making distribution of the effects of the herbicide much more difficult. I never understood the the fascination with mowing before spraying. The only practical reason is to remove the canopy which might prevent the herbicide from hitting the plants leaf surface where where it is absorbed. But it's a double edged sword. By removing leaf surface you reduce the number of pathways for the herbicide.

I think cleth is most effective on young plants. Older plants require much more skillful herbicide mixes and skillful application.

Number 2 I'm not sure about. I would say only after rain and if the temps cool. Before the rain in hot conditions your plant has shutdown making the movement of herbicide thru the plant much more tenuous.

 

[Wind Gypsy]

1. Its the root system that's the problem. Young plants tend to have top growth larger than the root. They are easy to kill because of this.

Contact herbicides are absorbed by the green part and distributed throughout the plant with the objective to kill the root - or that's the hard part.

An old plant's regrowth is supported by a now much larger root system making distribution of the effects of the herbicide much more difficult. I never understood the the fascination with mowing before spraying. The only practical reason is to remove the canopy which might prevent the herbicide from hitting the plants leaf surface where where it is absorbed. But it's a double edged sword. By removing leaf surface you reduce the number of pathways for the herbicide.

I think cleth is most effective on young plants. Older plants require much more skillful herbicide mixes and skillful application.

Number 2 I'm not sure about. I would say only after rain and if the temps cool. Before the rain in hot conditions your plant has shutdown making the movement of herbicide thru the plant much more tenuous.

Good stuff. This part "Older plants require much more skillful herbicide mixes and skillful application." leaves me wanting to learn more.

 

[Catscratch]

Thanks for the reply.
I mowed with no intention of spraying cleth, it was an afterthought.

The other is pasture that I brushhogged a month ago. Ironweed has tough leathery foliage that doesn't absorb well. I mow it before it flowers to deplete energy to the roots then spray the fresh regrowth later in the summer or fall. It's tough stuff. I don't spray it in the heat though at its not going to send a lot of herb into the roots. I do expect a flourish of growth with this front and moisture though. So I want herb on it sometime during this opportunity. Just don't know when timing is best.

 

[FarmerDan]

Good stuff. This part "Older plants require much more skillful herbicide mixes and skillful application." leaves me wanting to learn more.

It's simple and it's not! Glyphosate seems to have made what was once difficult seemingly simple. Expectations have grown right along side. Spray it and it will die, right? Is it better to be lucky or good? Maybe it takes both when the going gets tough.

There are a lot of variables to consider in the battle against weeds. Sometimes it's best to not do battle - or to wait for better times.
How many plant variables? Grass or broadleaf? Annual or perennial? Biennial? Characteristic of the leaf surface? Upper or lower stoma? Root system fibrous or rhizomes? Growth stage? Weather conditions? Temperature, humidity? Soil characteristics? Organic %? Soil pH? Herbicide type? Desiccant, contact or pre-emergent? Type and quality of the herbicide carrier? Water quality? And more....Oh sprayer type, pressures, nozzles.

It's enough to make your eyes roll back into your head. I highly recommend reading herbicide labels. Struggle with them and learn the language. I think most of the answers will be found there.

 

[Nightvision]

Thanks for the reply.
I mowed with no intention of spraying cleth, it was an afterthought.

The other is pasture that I brushhogged a month ago. Ironweed has tough leathery foliage that doesn't absorb well. I mow it before it flowers to deplete energy to the roots then spray the fresh regrowth later in the summer or fall. It's tough stuff. I don't spray it in the heat though at its not going to send a lot of herb into the roots. I do expect a flourish of growth with this front and moisture though. So I want herb on it sometime during this opportunity. Just don't know when timing is best.

If your iron weed and mine are the same thing neither Cleth or Roundup will kill that mess. I mixed roundup and remedy to spray on some a few weeks ago. It’s very dead.

Have you ever tried to hand pull that mess? That stuff is tough to pull up unless the soil is very damp.

 

[Catscratch]

If your iron weed and mine are the same thing neither Cleth or Roundup will kill that mess. I mixed roundup and remedy to spray on some a few weeks ago. It’s very dead.

Have you ever tried to hand pull that mess? That stuff is tough to pull up unless the soil is very damp.

No hand pulling of this crap for me. I brushogged 17 acres and let it grow back about 6 inches. Waited until after a rain and sprayed some marked areas (for comparison reasons) with crossbow (2,4d and triclopyr mix). Can't use gly as it'll kill too much pasture.

If you find a way to kill it without gly let me know! Thinking of trying milestone or grazon d+p next.

 

[omicron1792]

No hand pulling of this crap for me. I brushogged 17 acres and let it grow back about 6 inches. Waited until after a rain and sprayed some marked areas (for comparison reasons) with crossbow (2,4d and triclopyr mix). Can't use gly as it'll kill too much pasture.

If you find a way to kill it without gly let me know! Thinking of trying milestone or grazon d+p next.

I’ve had great success with milestone. Only issue is it has a loooong soil life and makes planting broadleafs tough for a while.

It will select for grasses so those will grow great. Problem is the grasses absorb alot of the herbicide. So if you’re a food plotter and cut, crimp, or leave the grass on the plot a lot of the herbicide stays in the plot for even longer than the soil half life.

Lots of issues with farmers using in pastures, then the hay gets cut and sold. People would put hay in gardens or such and all the broadleafs would die or not germinate.

So just be aware.