Crepe Myrtle springing up everywhere!

[Shirley G.]

Hello,
A little over a year ago we had our flowerbed boarder and sprinkler system changed. I've noticed that there were these new growth/sprigs of what appears to be part of the crepe myrtle sprouts all over.
It's invading the lawn! It started out localized near tree but now it's in all areas of the flowerbed with rock ground cover and it continues to spread ALL over! Every couple weeks I have to go out and dig up as much as I can.
What can be done to STOP this? I heard that putting weed killer will affect the tree.
One professional said it was seeking out water? Another said it was getting too much water.
Why is this happening . . . and how can I stop it.

 

[DirtMechanic]

Triclopyr stump killer. Nasty stuff, use as little as possible only upon what is necessary.

 

[Meadowlark]

One professional said it was seeking out water? Another said it was getting too much water.
Why is this happening . . . and how can I stop it.

LOL, the plant is just doing what it does...it spreads. I've grown them for years and have never seen one that wasn't invasive. For a "pro" to fail to tell you this is poor at best.

Personally, I would not use the stump killer. Way too much residual risk. The sprouts are very easy to just mow with your mower and after a few times they will give up...but probably spring up somewhere else....Its just what they do.

 

[DirtMechanic]

LOL, the plant is just doing what it does...it spreads. I've grown them for years and have never seen one that wasn't invasive. For a "pro" to fail to tell you this is poor at best.

Personally, I would not use the stump killer. Way too much residual risk. The sprouts are very easy to just mow with your mower and after a few times they will give up...but probably spring up somewhere else....Its just what they do.

Yeah. I do not like it myself. But I have had sprouts for 3 years. Also on a JuJube tree.

 

[Meadowlark]

Ever try salt, DM?

Applied generously, but focused directly on the plant will kill it, in my experience, but you are left with a brown spot for awhile. If you get lots of rain like we do here, this spot will disappear pretty quickly. Just plain old cattle salt...about $6 for 50 pound bag @ Tractor Supply. 50 pounds will kill a lot of sprouts.

 

[DirtMechanic]

Ever try salt, DM?

Applied generously, but focused directly on the plant will kill it, in my experience, but you are left with a brown spot for awhile. If you get lots of rain like we do here, this spot will disappear pretty quickly. Just plain old cattle salt...about $6 for 50 pound bag @ Tractor Supply. 50 pounds will kill a lot of sprouts.

Not on stumps. How many months before it clears?

 

[Meadowlark]

Stumps are another matter entirely...and for those I use a salt/diesel combo applied to the fresh cut stump...still preferable to me over Triclopyr .

The salt brown spot lifetime depends on the rainfall rates...easily gone in a growing season or less with good rains. For CM sprouts, my preference would be 1) keep it mowed short ( no brown spot, no chemical) , 2) salt applied directly to the plant ( no chemical residual but a brown spot that disappears fairly quickly with rain) or if a stump is involved 3) step it up to a salt/diesel drench ( longer lasting residual)

 

[DirtMechanic]

Stumps are another matter entirely...and for those I use a salt/diesel combo applied to the fresh cut stump...still preferable to me over Triclopyr .

The salt brown spot lifetime depends on the rainfall rates...easily gone in a growing season or less with good rains. For CM sprouts, my preference would be 1) keep it mowed short ( no brown spot, no chemical) , 2) salt applied directly to the plant ( no chemical residual but a brown spot that disappears fairly quickly with rain) or if a stump is involved 3) step it up to a salt/diesel drench ( longer lasting residual)

Yeah the fire dept used to use a mix of diesel and something like kerosene to keep growth off the hydrants. At some point they were made to stop, but it lasted a real long time. I guess its oily nature helped it hang around.

 

[cpp gardener]

Salt in a garden is generally a horrible idea. Yes, if it rains a lot is does wash out eventually but that's how the Romans prevented their enemies from reclaiming their territory (salting the fields). Diesel is just as bad for gardens and works much better as vehicle fuel. Use undiluted Round-up on stumps and Diquat (if you can get it) or vinegar to kill the sprouts. Like Meadowlark said, you can't stop it from resprouting, you can only remove the sprouts as they happen.

 

[Meadowlark]

Typical of the internet....blow something up from a directed spot treatment of a sprout to salting the entire fields , LOL. Exaggerate much?

I never ever recommended diesel treatment or salt treatment of a garden. Didn't recommend diesel to treat sprouts either, only isolated stumps.

... For CM sprouts, my preference would be 1) keep it mowed short ( no brown spot, no chemical) , 2) salt applied directly to the plant ( no chemical residual but a brown spot that disappears fairly quickly with rain) or if a stump is involved 3) step it up to a salt/diesel drench ( longer lasting residual)

Here is an example of a sprout salt treated this spring. The spot(and sprout) will be completely gone and covered in grass in less than another month. Vinegar is far less effective and much longer residual. Roundup? You must be kidding.

As I said a CM stump is an entirely different matter. Vinegar, LOL. Roundup won't touch it. Here is one from my yard cut about one year ago. Its dead, dead after the diesel/salt treatment. I'll probably dig it out completely with my back hoe this fall and you will never know it was there.

 

[cpp gardener]

It was an example of the effects. Just a larger scale. You brought up the diesel & salt treatment. Round-up is safer than anything you've suggested. Vinegar is for the spot treatments you would have people use salt for. Salt lasts forever, vinegar for a week maybe.

 

[Meadowlark]

.... Salt lasts forever, vinegar for a week maybe.

LOL, speaking of Exaggeration, boom there it is! LOL. One week, maybe for vinegar? Let's do a little experiment.

Here is a CM sprout that has been mowed w/ A jug of vinegar next to it. Let's see how long the vinegar lasts. I'll post again in one week. I already posted a salt treatment (lasts forever, ridiculous) and will update it also going forward.

 

[DirtMechanic]

I have been learning that some plants seem to favor compartmentalized root structures where it reminds me of a train made up entirely of locomotives. Knock one engine out and it does not matter. They can act separately. What they have in common is fuel sources and water. If you can take all of them at once from the outside you probably can use an organic means. I do not know how to get that deep in the earth without digging. But if something can get into their water or fuel nutrients that can also pass the obviously tiny restrictie doorways between sections then that works but is also most likely a modern chemistry. I wonder if there is something really slow acting, that can fully penetrate a root system before triggering the death alarm that closes all the doors on the train and prevents deeper penetration of the herbicide.

 

[Meadowlark]

Yep, its called the lawn mower.

 

[cpp gardener]

Are you testing the residual in the soil? That was the point, not how it affects the plant.