weed grass identification? (no pic available) (lawn, grow, 2014, crabgrass)

[gunslinger256]

I'm trying to renovate my lawn as cheaply as possible. Last year I had lots of clumps of tall fescue and I killed all of it in the early winter with roundup (hopefully I didn't jump the gun and kill the Bermuda too).

Lawn is supposed to be Bermuda but the sod was installed during the hottest part of the summer and I didn't get a chance to water it when I moved into the house due to a missing hose while unpacking.

1 part of the lawn has a lot of bare spots and the Bermuda is just starting to turn green with the warmer weather but I'm seeing small clumps of a taller grass that starts with red shoots. When I dig them out, the larger pieces of grass have a bulb like root (kinda similar to a green onion) with thick fleshy runners where the smaller red shoots emerge.

I suspect they might be Johnson grass but wanted to get some more opinions based on my description. I don't like digging them out and disturbing the soil but I think there's no other way. I think it might be too late to use roundup.

The pictures of young johnson grass that I've found on google image search don't seem to have red shoots.

[azoria]

Kinda like this?

Bio Bullies, Johnson Grass, Sorghum Halapense
http://www.naturalbiodiversity.org/b...on%20Grass.pdf

The pdf wouldn't let me copy & paste the photo. Nice pink stem right there.


Here is a baby Johnson, little pinkie





Crabgrass also has a red stem,





And then there is this:

"Johnsongrass, the latest entry to the lengthening list of glyphosate-resistant weeds — in both Arkansas and Mississippi — was announced in mid-March. It is the first glyphosate-resistant warm-season grass found in the United States."

Glyphosate-resistant johnsongrass in Mid-South | [primary-term] content from Delta Farm Press

[gunslinger256]

Thanks, azoria... that's it.

Yes it looks like the Johnson grass "pinkie", but where I have one, there's usually a handful of little shoots in a stand about 1 ft in diameter. So far I've dug out 2 stands. Hopefully I got all traces of it (I doubt it) within each stand.

I have an empty lot across the street with Johnson grass, and I'm guessing those seeds got blown over to my lawn. I did not have any Johnson grass last year.

I guess the gly resistant johnsongrass was going to happen sooner rather than later. I'm going to bet that I don't have gly resistant johnson though since I don't live anywhere near a farm. in my area we only grow rocks and cattle on a large scale.

[azoria]

You really should take a look at the Bio Bullies link, you'll see a fat pink wad of Johnson grass stems and a nice description, I have fought this plant before and lost. You might want to consider keeping the plot across the street mowed so that stuff has a reduced chance of getting into your yard. You'll never get rid of it.


"Johnson grass
is one of the 10 most
noxious weeds in the
world. It reproduces
quickly, and its seeds can
stay viable for up to 20 years"

[gunslinger256]

Yes I read the bio bullies article.

Every time I put down pre-emergent I get so much rain that it all washes away. I'll try to stay on top of it, looking for the tall shoots between mowings.

I'm sure the disturbed dirt will germinate crabgrass so it will quickly become a losing battle for another year.