The trees will likely be ok, but so will the woody plants you're trying to kill. The Roudup formulation for grass is not strong enough to deal with rose, poison ivy, etc.

I'm sure lots of other people will have opinions about the wholesale use of hebicides for home gardening, so let me just suggest that this may not be the best way to deal with your problem. Digging out as many roots as you can by hand is a tedious but far safer practice. Anything that re-emerges after that can be painted with an appropriate herbicide using a brush - far better than indiscriminate spraying.

i use credit extra .. generic roundup with sticker/spreader ... 41% concentrate according to the instructions for what i am trying to kill ... and i buy it in 2.5 gal concentrate ..

i use hundreds of gallons ,diluted, a year.. for 8 years running in my hosta beds.. under oak & cherry .... and in my conifer beds ... under all 500 of them .. i have seen no dire impact on anything ....

it is said to become inert on contact with the soil ... no one has proven otherwise, that i know of, contrary to some urban myths ...

to kill things.. it has to hit green tissue ... and in a high percentage of the green tissue ... if on a pine tree.. you hit two little bottom branches.. you arent going to kill a big, otherwise healthy tree, e.g. .. though the branch might die ... just the part sprayed ...

but the key in all that is READ THE INSTRUCTIONS ... there is a big difference between killing some chickweed and killing vines or poison ivy ....

i had a huge patch [half acre] .. it took 4 years to kill it all .. and then i left it fallow for 3 years.. waiting for the dead stuff to lose potency ... there is no way i could have done it by hand ....

never worry about your ash .. the EAB bug will kill them anyway ... in fact... you may want to take them out.. before you develop the garden any further ... contact your local Ag office to discuss if EAB borer is a problem in your area ....

should have no impact on the trunk.. since it isnt green ...

spraying.. per instructions.. with just a little practice.. is NOT.. by definition INDISCRIMINATE ...

the stuff isnt french perfume ... low pressure.. where you can see actual droplets... which fall to the earth.. rather than so much pressure that you atomize it like some cheap french perfume [where it can drift] .. is the key .. there are two adjustments you can make on the typical sprayer.. pressure.. and the little knobby diffuser on the wand tip ... find out how to make a course spray ...

practice with plain water on the driveway.. until you understand the proper use of your tool..

you have a very tough problem here ... use all caution.. use as little chemicals as you can.. and what you have to use... use per instructions...

but dont fool yourself into thinking this is something that is going to go away this summer ...

you spray the PIvy when it emerges.. it dies back.. and re-sprouts [30 to 45 days later] a few inches back on the underground vine ... then you respray it again ... and repeat that as many times per season that you can ... and for as many years as it takes ..... while you are doing that.. you also spray all the volunteers the birds have been dropping seeds for for decades ...

sooner or later.. you will weaken the underground vine.. and it will die ...

if any vines go up trees... cut them all, and paint 100% concentrate on to the cut ... that is in the instructions ... an old dish soap/detergent container is a good storage bottle for such ... and handy for dripping on cut brush ... mark accordingly for safety ...

i tend to leave the vines hanging in the trees for 3 reasons ...

one .. i am lazy
two ... its dramatic effect ...
three.. i dont care ...

just cut near the ground [where you can treat it.. and watch for re-sprout] .. and then again 6 or 8 feet up .. and they disappear from view ....

good luck
ken

ps: there are sprays specific to poison ivy, vines and woody problems ... you may want to look into those ... though roundup is rated also ... what you might want to try .. since they are different chemicals ... is changing the sprays each use ... a 2 fold attack .. but i wouldnt mix them.. unless .. yeah .... its in the instructions for both.. or you use the 800 number on both labels ... they are very helpful when you call them ...

Regular Roundup (if that's what you are using) can effectively kill poison ivy, multifloral roses, etc. It is more effective if mixed a little heavier than stated on the instructions. I usually mix mine about one and a half times the recommended strength for tough stuff like this.

Glyphosate (the active ingredient in regular Roundup) can be directly sprayed on the trunks of mature trees without any damage to the trees. It also can be spayed on the ground where tree roots are growing. It is absorbed only by actively growing green tissue. The only way it can get into the roots or bark covered limbs/trunks of trees is if there was a cut or wound, and, even then, it would have to be a large wound to do much to a large tree. Things you should watch for, if spraying around trees, is vaporization and wind. Set your sprayer to apply larger particles instead of ultra-fine mist, so that the chemical isn't blown up or vaporized up to the leaves.

If you are going to use lots of Roundup, you should check out the generic version. It's much cheaper and is the same stuff.

Glyphosate/Roundup is generally a very safe chemical once applied. It quickly binds to the soil and is broken down by bacteria in the soil. With reasonable care, I don't think you have to be very concerned about ill effects of roundup on your landscape or environment.

Yes.

If you are going this route, first don't spray 100 gallons all over the place. The trees should generally be OK with your care in spraying.

Now, what I've often done is take a string trimmer or similar and whack the heck out of the woodies, tearing the bark away and esp around the new growth. Prior to whacking, mix your generic Glyphosate half again as strong as the label says, and as Ken said use a sticker-spreader. Spray immediately after whacking.

Best to have someone coming along right behind you, spraying as soon as you move to the next plant and mark what you want to keep. If it is windy, wait for another time. Early morning is generally less windy. Take a big piece of scrap cardboard if you get near something you are concerned about and block spray with cardboard.

Go git 'em.

Dan

DON'T weed whack poison ivy!!!! I think Dan must have stock in the company that makes calamine lotion. LOL

!

I didn't see poison ivy in the original description. Yes, that would be bad advice. Maybe I should buy some stock soon...on second thought, the way our treasure has been raided and depleted, maybe not...

Dan

tsk tsk brandon.. on recommending uses not on the label .. lol .. or quantities not listed on the label ...

butt .. always one out there ... i wouldnt be surprised if the INSTRUCTIONS indicate a use that is double the recommended rate ... for something like poison ivy

the instruction book on large containers is hard to read/translate .. the product is sold for farm use... and breaking the application rates down to hand held quantities can be tricky ... but there are solutions of varying rates ... like 1% for easy to kill annual weeds ... 1.5 to 2% for perennial weeds ... and then higher for woody and brush ... up to 50 to 100% for killing stumps [with certain warnings] ... at least in the roundup booklet i am holding in my hand ... it would be easier to call and ask for proper rates.. that get the doctorate needed to interpret these things.. lol ...

for reliable and safe use.. PLEASE.... always use according to directions .... NEVER recommend otherwise.. no matter how good your personal witches brew might work ... been there. ... done that ... had kids.. now real careful ...

ken

Ken, mixing and applying "regular" Roundup (the 18% before mixing type, for instance) at one and a half times the recommended rate is actually much less dangerous than crossing the street. In general, I agree that it's a good thing to following instructions when working with pesticides, herbicides, etc., but in this case I feel completely safe in recommending the heavier mixing rate.

I do have some concern about the truly massive amount of this stuff that's currently being used in commercial agriculture, but in small amounts around the house, it's about as safe as any chemical you will ever use.

One caviat to otherwise good advice: While it is usually safe to get glyphosate on the trunks of old, mature trees, ie. trees whose outer bark is non-living, there is a specific set of conditions where that may not be advisable. That is, on very warm, very humid days. The reason for this is that, under these weather conditions, the bark opens up a little bit, often in too small an amount to be noticed by casual observance. What is then left exposed is inner, green, living bark tissue that can and will absorb the chemical. Also, tree species vary in their susceptibility to damage by this active ingredient. Elms, for example, are noted for their being generally more susceptible to damage than some other genera.

I mention these factors in the interest of our offering as complete advice as is possible. This by no means should be interpreted as a warning NOT to use the stuff. I use glyphosate-containing herbicides a great deal, and much of the spraying I do is directly adjacent to landscape plants. But I've been at it for decades and have developed my application techniques very highly. I think that if you proceed with caution and try to develop an awareness of all factors involved, you will find the product to be an invaluable ally in what you are trying to accomplish.

+oM

Very interesting advice here on roundup. I have heard of generic medicine but I have never heard or thought about generic roundup. What is it called and where do you buy it? The way cost of fertilizer and chemicals have gone up this year every little bit helps. Tks......DT

Whereever you buy your Roundup...just look further down the shelf for products that list "Glyphosate" as the active ingredient.

It's not that easy to find around here; the big box stores don't carry it. The best place I know of is Co-op or your local farm supply store. Farmers use lots of it.

I'm not fond of chemicals, and have had great luck killing underbrush using old plywood (cardboard will do, too, I just happen to have a good source of old plywood and various similar salvage materials). I lay out sheets of whatever is available, fill in gaps around trunks with newspaper (6 or so sheets thick, weighted down temporarily with rocks) and cover the whole unsightly mess with wood chips. Come back when the whole thing is rotted, and viola, the roses, poison ivy, even thugs (locally) like sweet autumn clematis and honeysuckle are gone.

Of course this doesn't work if you want to plant within a year or 2... but it's an option that makes the pests disappear from view immediately.

My Wal-Mart has another cheaper brand Eliminator weed and grass killer 41% glyphosate.