Crabgrass and how to kill it - PeachParts Mercedes-Benz Forum

cmbdiesel · #1 08-22-2010, 07:27 PM

This year saw an incredible invasion of crabgrass, literally took over 1/2 of my lawn. Anyone have any good methods of getting rid of it? This stuff is very thick and seems to have squeezed out the nice grass. My initial idea was to rototill, rake and reseed, but Swamp has suggested not tilling. (Thanks Swamp, I really didn't feel like tackling that job...) Suggestion was to cut very short and over seed. My question - would letting it burn after being cut short be beneficial? maybe spreading plastic or tarps over it to kill it, then overseeding?

The Clk Man · #2 08-22-2010, 07:52 PM

Quote:

Originally Posted by cmbdiesel

This year saw an incredible invasion of crabgrass, literally took over 1/2 of my lawn. Anyone have any good methods of getting rid of it? This stuff is very thick and seems to have squeezed out the nice grass. My initial idea was to rototill, rake and reseed, but Swamp has suggested not tilling. (Thanks Swamp, I really didn't feel like tackling that job...) Suggestion was to cut very short and over seed. My question - would letting it burn after being cut short be beneficial? maybe spreading plastic or tarps over it to kill it, then overseeding?

Drink some cheap beer and piss on the crab grass. Hey it worked for me.

MS Fowler · #3 08-22-2010, 08:09 PM

I believe that crabgrass is an annual; ie, it does not automatically return next year. this year's high heat and dry summer caused a lot of growth.

I believe the best solution is to over-seed your lawn this fall so that the good grass gets a start. Then, next spring, use a pre-emergent weed 'n feed. ( I prefer Scotts). That will prevent next years' crab grass crop from sprouting your yard. Use the good grass to crowd out whatever comes up.

cmbdiesel · #4 08-22-2010, 08:16 PM

Quote:

Originally Posted by The Clk Man

Drink some cheap beer and piss on the crab grass. Hey it worked for me.

I make my own... of both, and I have been applying the latter liberally for some time now. hasn't killed the crabgrass, but it makes me feel better

mattc · #5 08-22-2010, 08:17 PM

Here is one suggestion: (Please investigate further if this is what you need!)

http://www.nrrbs.com.au/chemicalsfusilade.htm

cmbdiesel · #6 08-22-2010, 08:18 PM

Quote:

Originally Posted by MS Fowler

I believe that crabgrass is an annual; ie, it does not automatically return next year. this year's high heat and dry summer caused a lot of growth.

I believe the best solution is to over-seed your lawn this fall so that the good grass gets a start. Then, next spring, use a pre-emergent weed 'n feed. ( I prefer Scotts). That will prevent next years' crab grass crop from sprouting your yard. Use the good grass to crowd out whatever comes up.

I did not know that. You have just given me hope where there was none

So we have mowing it close, then overseeding, maybe some fall fertilization?

cmbdiesel · #7 08-22-2010, 08:19 PM

Quote:

Originally Posted by mattc

Here is one suggestion: (Please investigate further if this is what you need!)

http://www.nrrbs.com.au/chemicalsfusilade.htm

Have you used this stuff?

layback40 · #8 08-22-2010, 09:07 PM

Dont let it flower & go to seed. Keep it short. Wiping with Roundup will selectively kill it.

Chas H · #9 08-22-2010, 09:15 PM

A number of specific crabgrass herbicides are available and I suggest you use one of them quickly before it goes to seed. I doubt you can mow crabgrass short enough to prevent seed head production. And if you do mow it when seed heads are present you will only spead the seeds for next years growing season. Round-Up will kill crabgrass and any other vegetation it contacts.

toddyvol · #10 08-22-2010, 09:34 PM

Ortho Weed B Gon MAX Plus Crabgrass Control Concentrate does a really good job. You may also have dallisgrass "Crow's Foot" which is hard to control too.

cmbdiesel · #11 08-22-2010, 09:35 PM

Quote:

Originally Posted by Chas H

A number of specific crabgrass herbicides are available and I suggest you use one of them quickly before it goes to seed. I doubt you can mow crabgrass short enough to prevent seed head production. And if you do mow it when seed heads are present you will only spead the seeds for next years growing season. Round-Up will kill crabgrass and any other vegetation it contacts.

One suggestion I got was to round up the entire area and reseed after it wears off. I really wasn't all that enamored of the idea of putting that kind of poison on a large area of the yard.
Haven't seen any seed heads, and am going to keep it mowed low for the rest of the season.
What about aerating to assist new growth in the fall? Will that give the overseeding a boost?

Chas H · #12 08-22-2010, 09:42 PM

Quote:

Originally Posted by cmbdiesel

One suggestion I got was to round up the entire area and reseed after it wears off. I really wasn't all that enamored of the idea of putting that kind of poison on a large area of the yard.
Haven't seen any seed heads, and am going to keep it mowed low for the rest of the season.
What about aerating to assist new growth in the fall? Will that give the overseeding a boost?

Killing all the vegetation is certainly an option. I'm doing that right now with a large patch of ground. If the soil is compacted, and given your bloom of crabgrass it prolly is, aerating can be beneficial. Do so before reseeding. Also consider applying a starter fertilizer and if needed some lime to raise the ph.

SwampYankee · #13 08-23-2010, 09:45 AM

99% of crabgrass is annual, there is some perennial on the scene now. The issue with selective crabgrass control products is residual, which will prevent reseeding for 2-6 weeks depending on the product (Weed B Gone Max is 4 weeks until reseeding) and many of them are a lot more effective when used before the crabgrass reaches the 5-7 tiller (blade) stage. By now, it's fully grown and difficult to kill with selective products. You probably won't see anymore crabgrass germinating at this point, but those existing plants will continue to grow until the first hard frost. The issue with the existing plants is that they're thick enough to prevent good seed-soil contact so you'll either want to mechanically remove it (or scalp it) or kill it before seeding if it's thick- or widespread enough.

BTW Fusilade is effective on crabgrass but is generally used in ornamental applications. Tall fescue is about the only grass that will tolerate it; it will kill perennial rye, bluegrass and fine leaf fescue. It's not labeled for residential use either.

A non-selective (kills all weeds and grasses) weed killer, such as glyphosate (the active ingredient in Roundup, there are many generics out there now that it is off patent), allows you to reseed within 3-5 days. It is going to kill your desirable grass as well so you would want to minimize your overspray as much as possible. While relatively safe, compared with other pesticides, it is still a chemical application.

Tarping or laying black plastic is very effective, although completely non-selective and does take some more time. I do work with a number of organic lawn care guys who use them prior to fall renovations in heavily weeded lawns. Lay them over the area for 7-10 days, ideally when it's hot and sunny, and anything underneath will be killed. It can often kill off some of the weed and crabgrass seeds near the surface that have built up over the years, waiting for their chance to germinate, thus reducing their pressure next spring.

You've got plenty of time to reseed, all of September and most of October, so go with whichever method you're most comfortable with. Often you can seed through part of November if Mother Nature cooperates.

We can get into pre-emergent crabgrass controls or organic options if you wish.

But the key is to remember the thicker the turf, the less of a weed and crabgrass issue you'll have.

cmbdiesel · #14 08-23-2010, 10:05 AM

OK... I think I have formulated a plan.... super low cut first, then aerate, then over seed. There may be a spot or two where I will try the plastic trick. What about getting more lime and fertilizer onto the places being reseeded? Before aeration?
Jeez, this stuff was so much easier out west where the lawn was meadow grass and never got mowed, watered, feed, or soil treatment. Of course, it looked like a meadow, not a lawn...

SwampYankee · #15 08-23-2010, 10:11 AM

Quote:

Originally Posted by cmbdiesel

OK... I think I have formulated a plan.... super low cut first, then aerate, then over seed. There may be a spot or two where I will try the plastic trick. What about getting more lime and fertilizer onto the places being reseeded? Before aeration?
Jeez, this stuff was so much easier out west where the lawn was meadow grass and never got mowed, watered, feed, or soil treatment. Of course, it looked like a meadow, not a lawn...

There's a reason the meadow look is making a comeback in lawns and golf courses...

Lime will never hurt with New England soils and will definitely help long term, especially if you're dealing with oaks and/or evergreens. Figure 10-25 lbs./1000 sq.ft. as a maintenance application and 50lbs.+ near/under oaks and evergreens. Any less than that really isn't worth doing. Use some starter fertilizer if it hasn't been fertilized within the past 4 weeks. Aerate first and broadcast everything afterward.