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Lisk
08-22-2005, 08:49 PM
Is it me or is crabgrass just totally taking over lawns this year?? In 8 years since doing lawns i never remember this much crabgrass. Even people that have treated lawns that never have crabgrass & some people with zoysia grass are even getting it!! Hows everbody's else's clients out there doing?

ProLawns
08-22-2005, 09:41 PM
Lots of crabgrass. I'm doing my pre-em apps later next year.

kppurn
08-22-2005, 11:00 PM
I have been seeing a lot more nutsedge than usual around here. Crabgrass is about the same as in the past.

jajwrigh
08-23-2005, 01:39 AM
Lots of crabgrass. I'm doing my pre-em apps later next year.


I am with you here 100%....crabgrass everywhere!! I don't think the early hot weather and dry spells helpd either... :angry:

sheshovel
08-23-2005, 02:04 AM
It is also possible to transfer crabgrass pieces and seeds on your blades and when you mow the next lawn you
"plant it".If mowing a lawn or area with alot of crabgrass you really should try and spray off your blades and wheels bfr the next lawn.
It snowballs that way.A crabgrass infestation can happen on your lawn route and it takes a few seasons but then it seems like all of a sudden lawns that never had it before now have it.
I'm not saying that's what's happening to your lawns....just that it is a possibility you might consider

GarPA
08-23-2005, 04:20 AM
I've also seen allot of this year. Good news is that its an annual and will croak as the colder weather sets in

On the subject of weeds, anyone notice that oxalis is really going bonkers this summer?

ProLawns
08-23-2005, 01:46 PM
It is also possible to transfer crabgrass pieces and seeds on your blades and when you mow the next lawn you
Yes, for this reason I try not to mow a nice lawn after mowing a lawn with crabgrass. Also, do the seeds have to lay in the soil until next season to germinate or will some germinate this season?

sheshovel
08-23-2005, 02:11 PM
The seeds germinate in early spring in warm climates and later in colder climates.So yes.. I'm not positive but I would assume that they would germinate the following year.
The problem with crabgrass is it can root from any tiny section of root or plant left alive in the soil or touching the soil will take root as soon as possible.
One weed plant can produce as many as 250,000 seeds
Crabgrass is found in lawn areas that get frequent surface watering.
In hot moist areas.
Infrequent but deep watering can help dry out crabgrass roots and kill them
or reduce their vigor,
A thick healthy turf will help also to control it.
If you must use a herbicide to control ,use one that is made to kill grasses not weeds.

kcchiefs58
08-23-2005, 05:48 PM
Also crabgrass seeds can stay dormant in the soil for about 25 years. :angry: this means it is a never ending job on controlling these weeds

ThreeWide
08-23-2005, 06:10 PM
Also crabgrass seeds can stay dormant in the soil for about 25 years. :angry: this means it is a never ending job on controlling these weeds

Given this fact, mowers transporting seeds has very little effect on whether other lawns get crabgrass. Without pre-emergent, virtually any stand of turf can be infested.

MIDWEST25
08-23-2005, 06:57 PM
If pre-emergents work why is there so much crabgrass.After 30 or so years of this I can safely say that if the sun is hitting the soil you have a chance of crabgrass.No pre-m on my lawn for 5 years now-no crabgrass. If you use an edger or weed eat edges low exposing the crack between dirt and concrete-GUESS WHAT-BINGO- CRABGRASS. Pre-m manufacturers(like lebanon)know the stuff doesnt work.I have won every argument with all of them.Till eveyone wakes up the multi-million dollar rip-off will continue.Read the labels. they all have an out.Barricade says water .5 inch 2 or 3 times a week apart.How in the hell do you pull that off.One 2 inch rain in the spring and they are telling you it won't work and they are covered simply by checking rain fall in your area.PBI gordan says they have a product that will change our industry coming in 06.Hopefully it will be a spray over product that will deal with this problem.APPLY COMMON SENSE PEOPLE IT DOES NOT WORK

ThreeWide
08-23-2005, 07:11 PM
When applied at the correct rate, at the correct time, with proper water afterward pre-emergents do what they are advertised to do. In most cases this means you a percentage of control in the 90 percent range. Exactly how long you get this control is dependent upon the application rate and how much rainfall occurs in the weeks following.

If you personally have had no crabgrass in your own lawn, that is attributed to good cultural practices along with sound fertilization. Most of us here might achieve that as well with our own lawns, but you cannot control what your customer does with his mower and irrigation system. For that reason, we need these tools at our disposal.

Problem is that if you apply pre-emergent on 100 lawns, some of them will fail due to things beyond your control. But I'd hate to see what my customers lawns would look like now if pre-emergent had not been used at all. Most new clients that I picked up this Summer were just swamped in crabgrass. I've seen only a few spots here and there with clients who received pre-emergent earlier this year. As far as I'm concerned, the pre-emergent did exactly what it was supposed to do.

ProLawns
08-23-2005, 10:13 PM
I was always told "apply your pre-emergent before the forsythias bloom". Where I live forsythias bloom the end of february. Pre-emergent are only good for about 6 to 8 weeks. So one app. of pre-em the end of feb. cannot possibly control crabgrass throughout the season. I've been doing two apps. the second one mid april. I still have crabgrass because the barrier cannot last long enough. Next year I will do first app. mid march and a second app. mid may. I'll probably still see some in aug. I used to think that crabgrass all germinated at once when the soil temp. reached 55 deg. I now know from experience that it germinates all summer. I'll have perfectly weedless beds one week and then a week later crabgrass popping up in them and this is august. It's still germinating.

ThreeWide
08-23-2005, 10:39 PM
Just as a comparison, most of mine got Barricade in early March.

This was planned to span 4-5 months, which it did as things are starting to wear out with the heavy rainfall. Had some light breakthrough, but nothing more than a spot spray on occasion. This was expected with the second wettest July on record. Without the heavy rain, it may have held up even better.

However I've already started applying Barricade again this month to close the window on Poa Annua before it germinates in September. An added bonus is that it also stops the crabgrass that is still germinating now.

This is of course for warm season grasses only. Our warm season grasses have high weed pressures in the dormant season as well. We do have to use quite a bit of pre-emergent spread throughout the year.

quiet
08-23-2005, 11:01 PM
Maybe I'm just lucky.

Barricade at 1/2 rate early last Sept for poa annua, then Barricade again at 1/2 rate in December of last year. I've had very little crabgrass all year long.

How much of a factor is the weather?

Ours has been extreme. Very wet all last fall - 13" of rain Nov. Nothing in December. Then wet again through March. Rain stopped completely in April. 1.25" on Mothers Day, 3" over Memorial Day weekend, then absolutely nothing in June with 100 degree temps. Nothing significant in July, but lotta light passing, spotty showers. Then red hot in August with 7" of rain in 2 days 2 weeks ago. Back to red hot (100) for last 2 wks.

Just starting to see some minor breakthrough now. Reminded a customer that we hadn't put any pre-m down since December. "Wow!"

Time to start the cycle over again.

cp
08-24-2005, 08:58 AM
I have always applied Pendamethalin in split apps and last year I started applying Barricade in a single app and did not like the results. We have a lot of varying weather conditions and our customers tend to over-irrigate. So after it's all said and done I'll be going back to Penda and spit apps.

Oh, I should say that the penda is in a 0-0-13 carrier so it doesn't affect my N totals.

CutNLawns
08-24-2005, 03:22 PM
With all the crabgrass and weeds this year what is the best way to attack them starting right now. What do you guys recommend fighting it...today? Thanks!

Mscotrid
08-24-2005, 05:55 PM
[. Pre-m manufacturers(like lebanon)know the stuff doesnt work.I have won every argument with all of them.Till eveyone wakes up the multi-million dollar rip-off will continue.]

Midwest, I'd be curious to know your arguement. I'd say you did win a arguement, they just got tired of hearing you complain.

cemars
08-24-2005, 07:22 PM
I was always told "apply your pre-emergent before the forsythias bloom". Where I live forsythias bloom the end of february. Pre-emergent are only good for about 6 to 8 weeks. So one app. of pre-em the end of feb. cannot possibly control crabgrass throughout the season. I've been doing two apps. the second one mid april. I still have crabgrass because the barrier cannot last long enough. Next year I will do first app. mid march and a second app. mid may. I'll probably still see some in aug. I used to think that crabgrass all germinated at once when the soil temp. reached 55 deg. I now know from experience that it germinates all summer. I'll have perfectly weedless beds one week and then a week later crabgrass popping up in them and this is august. It's still germinating.

That is a totally inaccurate old wives tale. The earliest crabgrass will germinate in Virginia is April, and this year it was closer to May. How early you start of course will depend on how many lawns you have to do. We start the last week of Feb. but it takes 6 weeks to get our 1000+ customers done. And most pre-emergence are good for longer than 6-8 weeks, in fact a single application of Barricade has lasted 16 weeks or more for me on a good percentage of the years I've used it, but as other post point out, length of control will be reduced on lawns cut too short or with thin stands of grass or wherever the barrier is disturbed by edging, drought cracks, etc.

grassworks
08-24-2005, 07:41 PM
So Gentlemen , those with faith in Pre Emergent( but not expecting every star in the solar system to perfectly align to make them effective) please tell me how long the crabgrass barrier will last if a customer waters their lawn every other day(15 min a zone ... maybe 2 inches or so a week) Will watering practices reduce coverage ?

Mscotrid
08-27-2005, 11:26 AM
You want the best control of Pre-E, get your customers to seed on a annual basis. Strong turf competition will win out everyday when combined with adequate moisture. Look at your break thru, 10,000 sq lawn. Industry and university data will support 96-98% control on an average year. What does the mean too you? You can expect 200-400 sq ft of annual grass & weed encroachment on your property. Bare in mind the plant is emerging from the ground thru maybe a quarter inch area involved. The plant surface coverage is the result of that one 1/4" area being weaken over the year. The plant might take up a square foot of ground space but your emergent point is a small spit spot in the ground.

The other area you have to look at when deciding on control application timing and products is your turf density. Thick, Moderate, Thin, Sun, Shade, Irrigated, Un-Irrigated, all those variables will determine your perceived success rate.

The products work, when everything else is considered.