View Full Version : Missed window for Pre-M

02-11-2009, 09:44 AM
I was talking to my lesco rep yesterday about my Crabgrass apps. He has me using Aquacap doing split apps. I know the timing of these treatments are based on soil temp. He is telling me I should have started my first treatment 2 or 3 weeks ago. He is convinced I have missed the window. He is making it sound like my yards will be infested with Crabgrass since I am just now starting my apps. Most of my yards, I have had for 2 to 3 years. Most of them had no Crabgrass at the end of last season. Do I need to be worried about my yards being infested with Crabgrass?


02-11-2009, 09:52 AM
it is possible, use two apps full strength dimension instead. although i am not from that far south, in theory this shoudl serve the purpose well as it has small post control properties. good luck

02-11-2009, 10:45 AM
I agree with grassman and your right is all about soil temps in the KC area they say that you should get your pre-m by April 15 but it can be earlier or later as it is tied to tempatures. Go and get a soil probe and find out. If you can't afford that I sometimes have used a meat thermometer in the past. Hope this helps. Use Dimension as well better for the grass.


ICT Bill
02-11-2009, 10:46 AM
Yeah we have had several calls from folks in south Texas that normally begin applying pre-m qorund the 15th of Feb but this year the soils were over 50 degrees 2 or 3 weeks ago. Very early spring

You should be good on sites that you used pre-m on last year, the sites that you core aerated will probably have some issues though and of course new sites that you had no control over last year

I think I would find another fert sales guy one that works with you rather than putting so much doubt in your mind

02-11-2009, 11:39 AM
Your guy is an idiot who went to one sales rep class I bet.

All kinds of factors come into play but the soil temp is a target to get your pre m down by so that it can keep the crab from getting started.

Did your mother tell you not to cry over spilt milk. It is what it is etc.

Go spray and if crab comes treat it. Get thick grass coming in so that crab cannot compete with it.

You are in this for the long haul not to get one app done in one week.

02-11-2009, 12:16 PM
Are your farmers planting corn? If not, its probably early.
Frost sensitive crops like corn are planted about the time crabgrass sprouts. Up here in Mich we like to be finished with our crabgrass control before the air temp hits 80.(About May 10th). Frost kills crabgrass. Also, I figure that we see crabgrass sprouting when the Growing Degree Days (base 32) hit about 500 to a thousand. Talk to your experts at TAMU. They should have an opinion on this. They should be able to give you data on the GDD, and the GDD from past years. Keep looking; you should be able to find this on the internet. (I gave up after 5 minutes).

02-11-2009, 12:49 PM
Switch to Dimesion forpost emergent control.
The corn advice is good.
Also if Dogwood hasn't bloomed you will be OK. IMHO
Buy and use a soil thermometer.

02-11-2009, 04:02 PM
On bermuda lawns that were really good last year, I wouldn't worry about it. You could even skip the pre-m and spray MSMA twice in the summer and have it looking great.

Go ahead with the aqua cap and don't worry.

Split treatments are mainly a waste of time. Put out the full rate of aquacap out now and save yourself some trouble on the next round. This might mean a little spot spraying next round instead of a blanket app.

02-11-2009, 11:11 PM
You didn't miss the window. Your average last frost date is still about a month away.

Turf Dawg
02-11-2009, 11:19 PM
You didn't miss the window. Your average last frost date is still about a month away.

Same thing I was thinking. Besides the "old timers" always say if it thunders in Feb it will freeze in April. Well last night we had thunder {besides the bad stuff}.

02-12-2009, 06:35 PM
Why do people always say "Use Dimension becasue it has some post emergent control on crabgrass."?

This is true, but at the time when Dimension is being applied, in late winter and early spring, there no crabgrass on any lawns. Crabgrass doesn't brake through until the summer and most are not spraying then. Then in early and mid fall the frost is about to get ride of it. So that logic doesn't really add up.

Can some help me with this?

02-13-2009, 09:35 AM
In central Maryland we do split applications of Dimension.
Our R-2 runs late April to early June. Due to the total number of R-2 accounts someone has to be last.
The post emergent activity helps us with those late applications.
Another issue for us is the fact that our territory is 100 miles across north to south. Probably a 10 degree difference in temperature.
Hope this helps.

02-13-2009, 10:31 AM
clallen the reason most people state that dimension has post emergent properties is one the label states that it will control up to the third tiller. Second most of us have had experience that it does. We will apply our pre-emergent in the first app at full strength and have had great results. Sometimes on properties we will apply a second round in late May of liquid dimension on top of our first round Barricade.