Johnson Grass

Anonymous Poster · Sep 17, 2002

I have a 1-acre orchard with about 125 mandarin trees. The Johsnon Grass is just going nuts! Tried a wick applicator w/Round-Up-- manual operation-- besides being very slow and innefective, I probably look like the village idiot out there swinging away at the weeds. Thought about mowing and spot spraying bases of weed. Don't want to use pre-emergent as I plan on seeding perennial clover this fall and spring. The stuff is goin' to town. Any one ever have to deal with this stuff. What would you do?

Thanks, Tracy

poorboy · Sep 17, 2002

Tracy we have about 40 acres that are prone to grow johnson grass due to spotty over flows. Most of the bottoms upstream are old corn fields signed up in goverment programs and out of production and tied up in estates and grown up especially in johnson grass. We keep it in check by spot spraying with roundup after the first cutting in May and June when the johnson grass shoots up above the grass. Another option is grazing. It doesn't like over grazing. Good luck and be constant in your endeavor.

Patrick

BB_TX · Sep 18, 2002

There is a chemical called MSMA that you can purchase at any good gardening center. I use it in my lawn. It kills wide blade grasses such as johnson grass, crab grass, dallis grass, etc. without harming my burmuda grass. Mix in a sprayer and spray the whole area. Works best in warm weather, above 85 degrees I think. Have to get it before it goes to seed. If the grass has gone to seed, you will have it again next year. but then you can spot spray with MSMA as you see it. Not sure how it would affect the clover.

em14 · Sep 18, 2002

BB_TX
What is the Brand Name or the scientific name of MSMA ... Here in this part of Florida we got weeds that are so mean that I think they could throw rocks at you ... if they could find one in the sand ...

BB_TX · Sep 18, 2002

I will try to remember to look tonight. It is made by different manufacturers. I don't think the one I have now is by Ortho, but it may be. I have bought it at Walmart and Home Depot. You will find it with the weed killers and such. It comes in pint containers and has large MSMA on the front of it. You mix a few ounces per gallon and spray something like 1000 sq ft. My junk grasses tend to come up in random locations, so I generally spot spray those areas although I have sprayed the whole acre before.

TerryinMD · Sep 19, 2002

Ack!!! Looks like this MSMA stuff may be kinda nasty. Clipped this from a web search:

Question - The question relates to the potential release of arsenic from the
herbicides MSMA (monosodiummethanearsonate) and cacodylic acid
(dimethylarsinic acid)after they are sprayed on soils. Both compounds
are tightly bound to soils, especially those with high clay content.
However, they are not substantially metabolized in the soil environment
in the absence of microorganisms.
Is the release of arsenic inhibited by the bond strength of the arsenic
to the methyl groups in the molecules? How do these strengths compare
to common compounds such as water, H2O?
---------------------------------------------------------
The following indicates that arsenic in herbicides has been known to cause
soil contamination:
http://www.waite.adelaide.edu.au/Soil_Water/nutrient.html

Here is another snipet.... be prepared for some mind-numbing language....

The uptake, translocation and metabolism of 14C-MSMA in organic arsenical-resistant and -susceptible Mississippi biotypes of common cocklebur were investigated. The two biotypes did not differ significantly with respect to either uptake, total translocation or translocation pattern of 14C-MSMA plus its radiolabelled metabolites regardless of whether plants were pretreated with 1.12 kg ai ha-1 of unlabelled MSMA or treated only with radiolabelled material. Absorption of 14C-MSMA was greater in unlabelled MSMA-pretreated plants than untreated plants, whereas the percentage of total absorbed 14C-MSMA that was translocated out of the 14C-MSMA-treated leaf was almost the same in MSMA-pretreated and untreated plants. Qualitative detection of 14C-MSMA distribution by autoradiographs confirmed quantitative results obtained with radioassays. Herbicide metabolism in the 14C-treated leaf showed that MSMA was not readily broken down in both biotypes and the extractable 14C was the same. Uptake, translocation and metabolic degradation were not involved in the mechanism of resistance of the resistant-Mississippi biotype common cocklebur to MSMA

I kinda, maybe think that it might say something bad... but then again... it kinda, maybe be something good. Translation please..... /w3tcompact/icons/shocked.gif/w3tcompact/icons/eyes.gif/w3tcompact/icons/laugh.gif

My curiosity is triggered by xxxx-icides. I like to look them up prior to using to make a educated decision. We tend not to use any herbicides or insectisides. Herbicides only in the fringe areas of the property away from our crops and only organic insecticides when absolutely necessary.

I think that the 2-D based herbicides are used also prior to the grass going to seed. You may also want to check into a pre-emergence to see if that helps. However, make sure that none of the herbicides - pre or post emergence affect your mandarins. Check with your local Extension Office, they should be able to assist you.

Good luck.

Terry

Good luck.

JRP · Sep 20, 2002

I have been spraying MSMA on a six-acre park area for a year now. It kills every thing except Bermuda grass. Some of the areas have not filled in with Bermuda and gets Johnson grass back. MSMA is a control, not an elimination. Overall, about 1/3 of the area has a nice Bermuda grass lawn that came up naturally - no seed! This MSMA is also cheap. I have 2 1/2 gallons in my truck right now. We mix 1 oz per gallon. It has worked well for me. Not sure about damage to your tree. If you want to make sure you don't contaminate your trees, try just mowing often and planting an aggressive grass like Bermuda.

Find a good turf site like Texas A&M University and search for MSMA and grass.

BB_TX · Sep 20, 2002

uptake, translocation and metabolism - radiolabelled metabolites - Qualitative detection - metabolic degradation /w3tcompact/icons/shocked.gif
My little brain went numb after reading that. /w3tcompact/icons/tongue.gif/w3tcompact/icons/crazy.gif/w3tcompact/icons/grin.gif