Roundup doesn't seem to work on these weeds...Help! (lawns, grow, Ivy)

[11jay11]

I have some weeds that I can't identify in my back yard..... well, I can't really ID anything but does anyone have any ideas about how to get ride of same??

2 pics attached.

MTIA
Jay

[no kudzu]

I can't identify your weed but I'm assuming this is not a current picture since it looks to be in full bloom. It will spread seed soon so you better pull them out before that happens. I've run across a few hardy weeds which are not touched by roundup and I just have to dig them up by the root and discard them by fire or grind them up. Don't put them in your compost pile. Some weeds (rattlesnake weed for example) spread by underground segments or bulbs like roots and they are almost impossible to kill by roundup. You might kill the top growth but they are not dead.

[TinaMcG]

When Roundup doesn't work, it's always user error. I'm not criticizing you. The label isn't crystal clear about the conditions you need to apply it under.

Flowering weeds will be harder to kill. Best to get them before they flower, but you can still try now. You just have to do the following:

1. Mix according to the package directions. You know that.
2. Spray on a cool and calm morning when you expect it to warm up in the afternoon. If the foliage is moist with dew or frost, that's best. The chemical is absorbed through the foliage and it is transferred down to the roots where it kills the plant. If the chemical dries on the foliage before it is relocated to the roots, it doesn't work. That's why you do not want any wind and also why the leaves should be moist before you spray. The longer it takes to dry, the better.
3. Be patient. A complete kill can take a week, maybe longer. You likely won't see any effects for the first few days. But if you follow the above instructions, it will work.

[suzy_q2010]

To add to Tina's suggestions, another thing you can do is add a few drops of liquid dishwashing detergent to the Round Up. It's a surfactant and helps break down the leaf barriers to absorption of the Round Up.

[Bulldogdad]

Roundup QuickPro will decimated that sucker.

[suzy_q2010]

Originally Posted by Bulldogdad

Roundup QuickPro will decimated that sucker.

It'll only kill 10% of it?

[11jay11]

I just bought it (Roundup extended control) gallon from Loews on Monday.

Do you think it's a good idea to add a few drops of liquid dishwashing detergent to the Round Up.??

[Priscilla151]

Originally Posted by 11jay11

I just bought it (Roundup extended control) gallon from Loews on Monday.

Do you think it's a good idea to add a few drops of liquid dishwashing detergent to the Round Up.??

I always add the detergent. I read you don't have to use as much roundup (if doing it by concentrate) in the mix if you add detergent. I wouldn't use less if it is a tuff weed.

[dijkstra]

Originally Posted by TinaMcG

When Roundup doesn't work, it's always user error. I'm not criticizing you. The label isn't crystal clear about the conditions you need to apply it under.

This is inaccurate. Some weeds such as nutsedge do not respond to Roundup due to their genetics. On many of these such as nutsedge where roundup doesn't work, MSMA knocks them down. It will take multiple applications as the plant reemerges to kill the bulbs but eventually it will kill it.

I'm not sure what particular weed is in the picture but it is possible that it is not susceptible to roundup.

[hiero2]

Count me in the camp that thinks this plant will respond, you just haven't gotten the application right yet. I think this is most likely. Some plants don't respond, ok, but not many. Roundup is a chemical salt, as I recall, and acts like salting the soil would - but the plant has to drink the application in through the leaves.

Some plants are difficult because they do not aspire through the top of the leaf (I don't think yours is one of these), and one has to apply the Roundup to the underside of the leaf to be effective. I have some local (Massachusetts) broadleaf that gets huge and acts like that. Getting rid of it is actually easier digging it up then it is trying to do the Roundup.

If the plant doesn't have a taproot, like dandelion and some others do, simply using a hoe to uproot it can be effective. If it spreads via suckers and underground runners (doesn't look like your plant, think poison ivy and bittersweet), then a hoe isn't necessarily a good idea, you just make it grow more! But, for something tough, like poison ivy, I use a concentration quite a bit stronger then the recommended dilutions.

I actually think I may recognize your plant - but I don't know what the name of it is - I just recall seeing similar stuff.

Although I see this is in a bunch of leaves, you may have this stuff in your lawn. I've had pretty good luck in the past with regular applications of corn gluten. Some lawns and parts of the country it works great. In Tennessee that was our experience. Here in Mass it hasn't worked well for us. Can't say why.