How to kill pampas grass?

We inherited a huge clump of pampas grass that stands at the entrance to our driveway. The exit from our drive is onto a blind curve, already nerve-wracking, but the blasted grass makes the limited visibility nonexistent. We cut it nearly to the ground last year and sprayed with RoundUp, but it is back full-size this year (probably 12 feet). It would probably take a backhoe to excavate the root ball, and is surely beyond me and my shovel. Just how do I eradicate the beast?

you probably have a lot of seeds left in the soil. roundup won't kill the seeds. if you keep mowing it, and not let it go to seed, it should eventually die after all the seeds have germinated. maybe years?

Try Poast? Your native wildflowers in the area won't be affected and that should theoretically get the Pampas Grass. It takes a while for it to go to plant heaven and sometimes you need to re-apply the chemical but sooner or later the grass dons wings and begins its journey up up up and away. Sheesh, Poast gets Johnsons Grass. I haven't met a grass that Poast couldn't get.

Even driving straight out of your driveway can be hard because the cars like to add to the speed limit.

Len, the clump of pampas grass is perched on a slope that is quite impossible to mow; wish I could. And yes, I'm sure the seed bank is considerable. I fully expect this to be a lengthy process, but what the heck, it can just join the ongoing ailanthus battle.

Equil, what is Poast and where do I get it? Sounds very promising, but a new one to me. Had to laugh at your comment about the driveway. So true; it may be posted at 25 mph, but folks fly around that curve at 50+ and we fully expect to get rearended someday.

Honey, you're not going to get rearended you're going to get broadsided by some moron adding the two speed limit signs together to come up with 50. I can't believe how fast they go down that road with the cop shop so close. They've got a death wish is all I can figure.

OK Poast... isn't called Poast any more but it's still a postemergence grass herbicide. Oops, didn't know the name changed, I'll have to discuss this with my bottle and tell it to update itself ;)

Here's a label to Poast-
http://www.greenbook.net/docs/LABEL/L26409.PDF

Here's the new and improved Poast (just kidding, same product under a different name)-
http://www.greenwoodnursery.com/page.cfm/12369?template=Plant
Better pricing here-
http://www.clyderobin.com/mixes/spec_grass_getter.html

There's a listing of the grasses it sends to grass heaven here-
http://www.greenwoodnursery.com/PDF/grassgetter.pdf
I use this product to kill quackgrass. I don't see Pampas Grass listed so you might want to call Greenwood Nursery and ask them for the # to get a hold of somebody to ask them specifically if Poast will kill Cortaderia selloana. Their phone number is 1-800-426-0958.

For what it's worth, this site says Round Up Pro gets it to don wings-
http://www.issg.org/database/species/management_info.asp?si=373&fr=1&sts=

It's a Tussock Grass so my thoughts are that Poast is going to get it.

I did some more poking around real quick. Looks as if Poast should get and looks as if Fusilade should get it but looks as if the two products used together will definitely get it.

Fusilade is another readily available product but (sigh) it's always been more expensive than Poast-
http://www.gemplers.com/item/G49785.html

Read this-
http://tncweeds.ucdavis.edu/products/handbook/12.Fluazifop.pdf

Based on what I just read, if I was only going to buy one product to try on the Pampas Grass, I'd be inclined to go for the Fusilade first.

Thanks for all the great information, Equil: most helpful, as always! We used RoundUp Pro on it last year, and it's baaack; so am glad to hear of other stuff that might be more effective.

That curve we live on is a bear, and people are idiots. The guy across the road has people land in his lawn all the time, so guess we should be grateful we're on the high side.

I was wondering about Round Up Pro. Guess you answered my question. I prefer to use grass herbicides anyway as grass always seems to get in where I've got other plants growing.

I'm with you on that; but unfortunately I have to use RoundUp where the last of the vinca and the eternal ailanthus come up on my slopes. I sponge it on, though, to minimize damage to others. I tried another round of hack & squirt on the female ailanthus at our entrance again today; wish me luck. The two smaller trees on either side of mama at the driveway entrance did not leaf out at all this year (yes!); how long do you think I have to wait before cutting them down, in order not to risk root suckering? The tops may be dead, but how do I know when the roots are?

BTW, got a copy of Gempler's master catalog in today's mail (quite a tome), and will order the Fusilade. Thanks again.

I'd say it's time to uncork the bubbly! Good job.

So they didn't leaf out, shame boo hoo whaaaaaa! I'd cut them down to about 18" when you get a chance and paint the stumps with the same happy juice. Do not use a concentrate. Regular strength will be fine. Patience is a virtue. Glad you waited a bit to cut them down. Go for momma again the same way we discussed. Then if momma doesn't leaf out next year, cut her down to about 2' and paint her stump with more happy juice.

When I used the hack & squirt approach with mama today, I noticed that on one side/arc of the trunk, the wood is very dry and brittle to a depth below what would be the cambium layer. Unfortunately, this is true on only a small arc of her circumference; the rest of the wood still shows life when you hack into it. She has some limbs that didn't leaf out this year, but many others that did. I think I'm managing to hurt the beast, just need to finish her off. If we can safely take down the smaller trees on either side of her, it will be much easier to work on the mother (as it were).

Hack into other areas of the tree where the chemical can be "sucked" down by viable cambium for lack of a better description. The area you described is toast so applying chemical to it would be a waste of product. Go for the areas that show life as you described it.

You're getting the momma. It just isn't happening as fast as you or me would want it to happen. Now, if you could slip out under the cloak of darkness and get to those grandparents the neighbor has...

if all else fails, just break out the propane torch! lol

Now that's tempting, Len....

Equil, while working on mama ailanthus, I couldn't help checking out the neighbor's yard/landscaping. In addition to the monster ailanthus that line their property, they have a large square area mid-property that might once have been landscaped: it is now a solid stand of ailanthus, probably 20' x 10'. Their other keystone plantings are buddleia and hibiscus syrica (sp?). I'd like to slip out under cover of darkness and air-bomb the entire property with strong chemicals. Did I have to move in next to InvasivesRUs?

I loooooooove my Weed Dragon. I use it on quite a few noxious weeds and invasive plants. One problem with torching Ailanthus altissima, fire doesn't exactly do much other than to make it mad. If you try to torch this plant, you remove all the above ground vegetation and all those nice roots are left below the surface to shoot up new growth with a vengance. This tree would be classified as fire adaptive in my book. Not a tree that's going to do much but laugh at you if you try to nail it with a propane torch. It's the Arnold Schwarzenegger of trees, it's literally going to snap crackle and sizzle while hissing out, "I'll be back".

Oops, typing when you were typing.

Hibiscus syriacus if you want to do any online searches. Rose of Sharon is very popular around me. So much so that I do get volunteers on my property. Blech.

As far as checking out Buddleia, also check using Buddleja because that's how the USDA site spells it. Great, everybody and their brother spells it Buddleia (myself included) and the USDA site doesn't even have a prompt that instructs you to check for that beast under their spelling. Lookie here-
http://plants.usda.gov/java/profile?symbol=BUDA2
Isn't that cute? A butterfly bush is a butterfly bush no matter how you spell the Latin name but no wonder why so many people go searching for information and can't even find out if the plant is native or introduced let alone invasive.

Really sorry about your neighbor's plants. I know how frustrating it can be when their plants end up on your property. I could run down the entire list of what's ending up on my property but the plants that are bugging me the most and creating the most work for me these days are that Siberian Dogwood, White Mulberry, Burning Bush, Norway Maple, and that lousy Barberry. I have dreams of nuking my neighbor's plants. Tree of Heaven is just now beginning to make its presence known but I know to get rid of those the minute I see them.

Satisfying as it would be, Lauren, I know better than to torch the ailanthus; but boy would it feel good.... I have developed immense respect for the adaptive and regenerative properties of this beast (the Arnold etc. is a great description); immense respect along with immense hatred. I has become very personal between me and mama ailanthus; I'm determined to outlive her if it's the last thing I do (lol).

You'll love this, Lauren. Was recently talking to someone at a local nursery about the erosion problem around our perimeter, that's undermining the old oaks and pines. They suggested mass planting of Siberian dogwood. Yeah right, for sure. Need I say I left without purchasing anything there? Granted it would no doubt take hold and help with the erosion, but the cost is way way too high, thanks.

The local big box stores are always chock-a-block with butterfly bush and Rose of Sharon, so the average joe buys in because they're pretty and easy. Another place I'd like to air-bomb with chemicals....

Siberian Dogwood? Firesale on the plant in your neck of the woods?

Did you ever check into the geotextiles I mentioned for erosion control? What about planting more natives with their nice deep roots? Grasses can help too and besides which, you have a bird lover over there.

Sorry if I'm changing the subject, but I'm not finding much at all about Siberian Dogwood invasiveness - I searched Cornus sericea var. sibirica, C. alba, Siberian Dogwood, etc., each + invasive. What can you tell me? I don't grow it, just a curious Dogwood fan.

For what ever reason, it loves this area. I pull out literally hundreds of seedlings all because my neighbor had two mature plants in her front yard. I guess spartacusaby must have the same problem where she lives. We've been spotting escapees in natural areas for quite some time now. Dogwoods are great, just not this one.

No need for apology, claypa; we're already well off the originial topic of pampas grass (lol). We don't have a problem (yet?) with the Siberian dogwood in this area, but it ran amok in my old VA stomping grounds.

Equil, the problem with planting anything on the perimeter slopes that are eroding is two-fold. One, DOT comes through at random intervals to mow and chip it all to bits; thanks to their efforts doing so last fall, we've had an explosion of ailanthus root suckers this year. Two, the slopes are sufficiently steep that there simply is no place to stand and dig to plant things on those slopes; we could clear out at the bottom and plant there, but that wouldn't help erosion at the top. The native grasses do interest me. I'd thought of eradicating the lawn in the area beside the house, behind where Sandie's strawberry bed is, and planting that in native grasses; but the bluebird house back there has been in nesting use all season, and I don't know if the tall prairie grasses would chase off the bluebirds. The best approach I can come up with for the perimeter is to plant a new ring of trees inside the existing ones that are threatened by erosion. Hopefully this would help hold the soil at the top; and if we ultimately lose the existing old trees, the new would maintain the privacy we want. This is an expensive project, and must needs proceed slowly. This fall I hope to plant the first three or four trees in the area most subject to erosion: maybe a couple acer saccharum and one of the tall, fast-growing thuja natives. Would also like to put in some stuff that's deep-rooted to hold the soil (maybe nyssa?), but they take so darn long to establish and take off. It's a work in progress... or at least planning progress.

Contact your county ecologist/biologist for this one. Maybe he/she can give you some suggestions.

I don't think prairie grasses would be a problem for the bluebirds but you can contact somebody at www.sialis.org for more information.

Yah, I tried contacting the county extension service for erosion advice. They eventually sent out an agent who gave us a brochure on native plants to prevent erosion in wetlands. Now if we had wetlands, that would be most helpful..... but we have a dry steep slope.

Perhaps the extension office knew something we don't know? Expecting any floods here in the near future?

I'd call back the extension office and share your experience with them and ask them to please be so kind as to provide you with more appropriate information or direct you to someone who is in a position to do so. That seems sort of unacceptable to me. What are you supposed to do... trench out your front yard and create a wetland?

if the old oaks and pines don't stop the erosion, i would say more extreme measures are needed. and if it is in the highway dept right of way then you will probably need to talk to them as it is their responsiblity.

I agree with Len123 and think you should contact them to see what they suggest since a portion of the area you want to improve is going to be maintained by them.

Back to this erosion control deal, think along the line of a mixed privacy screen. A mixed privacy screen will serve you well in the long run because if you lose one out of the lot, it won't be that noticeable.

Here are my thoughts at this point, if you can't beat em, join em.

Aesculus parviflora, it suckers. Excellent plant for erosion control not a lot of height though but it can hit upwards of 10' and provide some privacy within a few years. Plant toward the base of the slope with this.

Amelanchier arborea, extensive root system and can definitely be used for erosion control. Some decent height on this probably around 25'.

Oxydendrum arboreum, it colonizes. Nice tree. Don't overlook it because I found where it is used for erosion control and it has decent wildlife value also. I'm trying to get a few going out my way too.

Hamamelis virginiana- frequently used for reclamation and erosion control based on what I'm reading. I've got it here but more as a specimen as opposed to a work horse, love it. Nice winter interest to this too.

Nyssa sylvatica- good choice!

Maybe toss in a few of the following for Sandie which are used for reclamation work and erosion control-
Clethra alnifolia (mid range erosion control but should be fine companion planted with others)
Callicarpa americana
Calycanthus floridus (another mid range in the erosion control department but by you it should sucker)

Instead of the Sugar Maple, what about the Southern Sugar Maple?

Read this about Asmina triloba-
http://www.glo.gis.iastate.edu/la302/p6resrep/christine_StreambankBioengineering.pdf
Looks interesting. Never thought of that tree as anything but wildlife value but... might be worth a second peek for your site.

I've not really used an oak for erosion control. Seems as if there have always been better choices. Doesn't mean one couldn't be used, I've just never used one.

All the above are native and occur in your area to the best of my knowledge. Get a good mix of plants with high wildlife and erosion control values going with a nice layer of mulch and I'd think you'd be good to go. You can work on other vegetation later.

Maybe you could run these suggestions by your extension office and see what they think?

LOL at the thought of expected floods, Equil; maybe they know something I don't? I was seriously underwhelmed by the help from county extension service. The agent apologized that the wetlands brochure was all she had; she promised to send more appropriate suggestions, but that hasn't happened. I have yet to get anything helpful from them, and won't call again, thanks.

Love the suggested plantings, and thanks much for them. Have several of the ones you mentioned, but not in the perimeter area (calycanthus, clethra, aesculus parviflora, also aesculus pavia). Most just went in this spring, but I moved the clethra in early spring from a location where it did nothing last year, and it's now started to take off. The aesculus and nyssa are especially appealing because they're tap-rooted; but as a result, they seem so darn slow to establish; the aesculus I put in this spring have put on very little appreciable growth to date. That may mean they're concentrating on root growth, which would be favorable for erosion control, I guess. Is my logic correct here, or just wishful thinking? Will definitely check out the amelanchier, oxydendrum, native hamamelis, asmina, et al; all sound promising. I agree that a mixed planting is the way to go. Tell me more about the southern sugar maple; what's the botanical name? The sugar maple appealed because of the combination deep and surface rooting, to help with erosion; and frankly to add some fall color to the place. I love the old oaks we inherited, but with them and pines as the primary plantings, the fall color is pretty ho-hum.

We've been without internet, phone and TV for over a week because while tilling, I cut the cord: major oops, and the cable company's customer service is essentially nonexistent. Am busy catching up on life in the twentieth century...

BTW, my order for Fusilade and its surfactant arrived during internet hiatus. Sprayed the pampas grass beast today and will hope for the best (or from the plant's viewpoint, the worst).

I thought I would throw in my two cents here. Grass Getter- formally Poast, is what they deem a POST-emergent. This is what you spray on AFTER you have whacked back the grass after it has emerged from the ground. Yes, it does really work!!! But to get the seeds that are already in the soil that haven’t emerged yet, you need a PRE-emergent.

This is the copy from the website for the Grass Getter. It explains it better than I can.


• Post-emergence, selective grass killer for weed control over the top of bedding plants, ornamentals, groundcovers, shrubs and vegetables.
• Controls annual grasses as well as hard to control species such as Bermudagrass, Johnsongrass and Quackgrass.
• (Includes one bottle of Grass Getter and one bottle of Herbicide Helper oil concentrate)
• Available in ½ Pint, Pint

This is the copy for the Pre-emergent Surflan – Weed Impede


A great preemergence herbicide for use on ornamentals, trees, roses, bulbs, and garden grown fruit trees. Very economical to use, 1 pint treats 5-10,000 sq. ft. Lasts up to 6 months to control grasses and weeds and you can tank mix with Remuda or Roundup in unplanted areas. Note: Remuda is our new product that is the same as Roundup.
• Pre-emergence herbicide for use on ornamentals, trees, roses, bulbs, iceplant and garden grown fruit trees
• Economical--1 pint treats 5-10,000 sq. ft.
• Up to 6 months control of grasses and weeds
• Tank mix with Roundup® in unplanted areas
• Available in ½ Pint, Pint

Since we have learned what the weeds are first, then trying to kill them, the steps this fall to take would be, post first, and then pre second, with a double shot of pre this spring to make sure you get anything left from fall.

Oh, and Equilibrium, thanks for the kudos!


This message was edited Sep 17, 2007 10:30 AM

Thanks, greenwood; appreciate the input. I got the Fusilade and, per instructions, sprayed the clump of pampas grass without cutting it down first. Frankly, it seems to have had little if any impact. Granted that this is a huge and very thick clump of grass, making it hard to thoroughly wet the foliage. I'd expected that I'd need to treat it more than once, but am surprised to see it look as if it shrugged off the whole first treatment. Maybe I should whack it down to manageable size/height before treating again? Don't quite know how to proceed from here.

Sorry, I've been gone. Speaking of floods... while I was gone we were hammered. Over 20" of rain in a very short period of time. Not much I can say. Rather depressing to come home to such a mess with standing water in every depression on the property and a "vernal" creek running full blast. The sand box for the kids (4' deep and elevated 1.5' out of the ground) looked like a frothing sea of dirty filthy water complete with a few cat turds floating on the top. Must remind myself to place plywood over the top to keep out the stray cats.

I've done stupider so don't feel bad. Here's a recent move that was real swift- I have a new computer and purchased and installed a firewall that I don't know how to use and I can't see any photos here at DG. Isn't that special? Guess I'm going to have to learn how to allow some cookies or something.

Based on my experience, grass takes what seems to be an incredibly long time to show signs of weakening in preparation for entering the pearly gates. I've frequently had to reapply. I realize the label doesn't instruct you to whack it back but I'd do what he/she said to do. Whacking it back certainly can't hurt and evidently he/she has had greater success whacking first then spraying so go for it. I'd try it. Why not?

The Surflan is a product that I've been meaning to get around to purchasing to try around my fruit trees. I don't like competition from weeds for nutrients around the bases of my fruit trees. I've not tried it before because it's on that long list of things to do but I don't think it would be a good idea to use that product anywhere your native herbaceous plants are growing... which is just about everywhere for you.. and just about everywhere for me too other than in the little hobby orchard.

You're welcome greenwoodnursery. I linked to your nursery because that's where I bought the product a few years ago. Good thing I actually posted that above because I've lost all the favorites out of my browser from the old computer. This means I don't know where I bought anything any longer other that the Poast... which isn't called Poast any longer ;)

Welcome home, Lauren, but oh what a sight to come home to! You must have wanted to cry...or curse...or both. Good luck with the reclamation project. And thanks for sharing about your new computer/firewall snafu; makes me feel just a bit less challenged.

I think I'll try hacking down the clump of grass and then respraying with Fusilade. The stuff was pretty costly, when you add in the necessary surfactant, so want to give it every chance to work before investing in an alternative. I'd hoped to use it to kill off grass that keeps coming up between planned plantings; it comes with a long list of species that have varying sensitivity to it, so must study that carefully before spraying around anything desirable, esp. the natives.

Meanwhile, I've been trying hack & squirt on mama ailanthus every ten days for a couple weeks now. Have fond dreams of preventing her from leafing out next year: please please. The ongoing drama of pulling her seedlings and killing her root suckers continues, of course, and will for years. [At least the seedlings will continue; hopefully the root suckering will die when she does.]

What I wanted when I came home was recipes for stray cat- just kidding but I didn't realize there were so many turds in the kids' sand box until we got hit with those rains. That was pretty gross and the thought of urine laden sand that goes with the turds was too much. I called a guy with a bucket to come over and remove all the existing sand and haul it off the property then I'll have clean sand delivered. The sand box is literally a total of 5.5' deep and the outer dimensions are 10 x 10. Expensive litter box. The visual of so many floating turds was way too disgusting for me and there was no way I could get rid of that much sand myself.

That article I pulled up many many posts ago suggested that the use of Fusilade and Poast together was the most effective on pampass grass. I'd give it more time.

So you're going for the momma Ailanthus! You go girl! You know what I've always day dreamed of doing? Ripping every last leaf off of one of those trees.

I came across something called Tordon RTU on ebay. It says it works on tough trees like ailanthus, and has a blue dye in it so you can see where you have put it. There's no mixing or anything, you put it on the stump (or cut) straight out of the bottle. Have any of you ever tried it?

I've used Tordon before. The RTU stands for Ready To Use and the blue dye is definitely a plus when you are painting a bunch of stumps because all stumps start looking alike after a while. You can easily see which ones have been treated and which ones haven't. Makes painting stumps mindless work.

I use Tordon RTU all the time, but I guess nobody listens ;( The stuff works great on Ailanthus. Fortunately, the Ailanthus I had removed is gone, no suckering at all. I do have the seeds of course which do sprout, but they're so easy to pull. It's the neighbors who don't use a weed whacker of any kind, that I have to cut down the Ailanthus and spray on the Tordon RTU. If only the church behind us would cut the female down in their lot. And of course the people 2 doors down with the male.......

Is a covert mission in the planning stages >>> ;)

For me? It's a church Equil! I can't do that....no no no....I will not do that! I can ask and I can plead, but I cannot do anything like that. It's not in me on other peoples property, no matter how much I hate the tree.

Digging out pampas grass by the roots is almost impossible without a backhoe. I finally got rid of a huge clump but it took 3 years. We hacked it down with a machete, and then covered the stumps with 4 layers of heavy plastic held down with a load of rocks. (It looked like a small rock island)

I don't know how long it took to actually die but when we moved the rocks after three years it did not grow back.

We had tried spraying with round up pro. and several orhers but they had very little effect. We burned it to the ground 3 times and it came back lusher than ever. But without light and air it died.