My name is Jason Davis and I am new to the neighborhood. We just moved in on Stonehaven.

I was reading through the forums and noticed a common topic: weed control.

In another life, I worked (and studied) in the landscape industry. My first degree was in golf course and landscape management. I have my irrigation license and used to have my pesticide license but I let it go back since I changed professions. I now work in the IT industry. I was employed by a landscape company as the chemical director. The company had very prestigious clients, EDS, Galleria Mall and the Dallas Market Center, just to name a few.

I am happy to share my knowledge with anybody who has the patience to listen to me talk about something that most people find extremely boring.

Now, down to weed control.

Most generally, we all have two types of weeds that can be further divided into two types. The main types are Broadleaves (Dicots) and Grassy weeds (Monocots). You can easily determine which you have by looking at the veins in the leaves. If the veins run parallel to each other, it is a grassy weed. If it has webbed veins, then it’s a broadleaf. That’s really all you need to know in order to get the right chemical kill the weeds.

These two classes can be divided again by classifying them as either an annual weed or a perennial weed. This simply means how long it takes for the weed to complete its life cycle. An annual will come up from seed, mature, produce and drop seeds, and then die, all in one year, hence the term annual. Other weeds (perennials) will come up from seed, mature, produce seeds, and then usually goes dormant, but comes back from the original plant the next year.

It not necessary that you know whether a weed is an annual or a perennial to treat it, but knowing this lets you know what you can control with a "pre-emergent" herbicide. This type of herbicide forms a barrier on the surface of the soil. When the little seed (perhaps one coming from your neighbors weeds) lands on your lawn, the seed will begin to sprout, but when the first little root comes in contact with this herbicide, it will die and go see God. Certain type of pre-emergent chemicals are better for grassy weeds and certain types are better for grassy weeds, but pre-emergent herbicides only works on annual weeds. It is useless for existing weeds that you already have.

For weeds that you already have, you need a contact herbicide. These work best when applied in a liquid formulation. (If you use a granular weed and feed product, it is best to have a wet lawn when you apply this product because you need the granules to stick to the leaves of the weeds in order to kill the plants.) There are three general types of herbicide. One is Nonselective herbicides (i.e., Round-up). This type of herbicide will kill anything with a green leaf on it. The next two types are selective herbicides. You can purchase herbicides that only kill broadleaf weeds, or you can purchase ones that only kills grassy weeds. Broadleaf weed killers usually contain three types of herbicides and have a broad level of control. The most commonly used one is 2-4D. (I will sometimes refer to this type of herbicide collectively as 2-4D, but I am referring to the three-way mix of herbicides). The grassy weed killers are generally used to spray over your flowerbeds to kill the Bermuda grass that is growing there, without harming the flowers that you have in your bed.

One of the hardest types of weeds to get rid of are grassy weeds in a lawn. If they are an annual weed, (i.e., crabgrass) you can control them pre-emergent herbicides. If they are perennial weeds, (i.e., Dalligrass) you must use contact herbicides. This is the harder group to control because there are not any chemicals on the market yet that selectively kill weedy grassy yet not harm your Bermuda or St. Augustine Lawn. We do have one chemical, that although it is a Non-selective herbicide, it is more toxic to the weedy grasses than it is to Bermuda grass. If you have a St. Augustine lawn, the only way you can get these out of your lawn is by using the best horticultural practices. For Bermuda grass lawns, you can use MSMA. The catch to this herbicide is that it requires repetitive, low strength application. For an established Dallisgrass plant, it can take as many as 5 or 6 applications before the Dallisgrass will be weakened to the point that it will go see God. This herbicide is temperature sensitive (meaning is mix rates vary with increases in temperature) and it’s not quite warm enough for this to be very effective. Since it is a non-selective herbicide, one has to be very careful to apply it correctly. Applied improperly, it can burn up your entire lawn. I can teach you how to spray this herbicide, but it’s not something I can teach you how to do effectively in written communication.

So, here's your shopping list:

If you haven't applied a pre-emergent herbicide, you need to. This herbicide comes impregnated on a fertilizer granule, so it will be in a bag. Although it is really too late to do the most good, it's better to put it down late than not at all. Look on the back of the bag for the active ingredient "Pendimethalin". The most common formulation is .86%. With this formulation, one 50 lb bag will treat 10,000 square feet (roughly twice the size of most of the lawns in our subdivision). Go ahead and use the whole bag on the lawn though, as it works best when you get a good base down, and then keep applying it every season. Cost- $15 or so per bag. You use your fertilizer spreader to apply this product.

To kill the weeds you already have, you will need a contact herbicide. You can also buy this in a granular form; however it is not really very effective. The liquid applications are best. You can by the chemical in a hose-end sprayer type of application and it works much better. You just screw it on the end of your hose, turn on the lawn, and then aim the sprayer at your lawn. The major problem with this type of application is that the manufacture "water-down" (forgive the pun) the active ingredient so much because they don't want to be liable for damage to your lawn by making it "simple" enough to be used by homeowners. The most effective type of application is through the use of a low volume sprayer. This requires a little math to calculate how to apply the product as well as the math required to mix the product to the correct strength. (This is also the cheapest way to go. The cost of chemical for an average lawn is about 50 cents) If you want to go this way, but don't have a sprayer, give me a call. For a small donation (whatever you feel is reasonable) to my children’s college fund, I'll spray your yard for you! The active ingredient you are looking for on the back of the bottle is 2-4D, or Dicamba, or MCPP, or MCPA. If you see any of these initials, this is what you want. DO NOT SPRAY ANY OF THESE CHEMICALS ON ST. AUGUSTINE LAWNS!!! If you’re not sure what type of lawn you have, call me first before applying anything.

The next thing you need is fertilizer. This is a whole other topic. What I recommend is a 25-5-10 with about 2% iron. This can vary in cost, depending on the slow-release characteristics of the nitrogen source. Try to match up these numbers as close as possible and make sure you see iron on the bag. Iron caused the leaves to turn deep green, but doesn't cause the grass to grow. The cost of this can vary widely. If you by a name brand, you might be paying more for the brand name but by and large, you pay for what you get. If you by the cheapest fertilizer close to these numbers (the nitrogen will most likely have no slow-release characteristics. This will mean that in a week, you will be baling hay in your front yard. In the future, depending on response to my suggestions, I can purchase fertilizer in bulk for all of us, and save us all about 30% over the retail prices. We'll see how that goes in the future, but for now, you should know enough to get your lawn ready for the summer.

If you have any other questions, regarding anything in the landscape feel free to ask. I can offer advice on most everything in the landscape from ant and insect control to disease diagnosis and treatment as well as drainage and sprinkler issues.

By the way, if you are looking to purchase seasonal color, I can get them for you for $7.56 per flat (18 count, 4 inch plants). Actually, I’ll let you borrow my discount card at Home Depot and you can buy them yourself at this price.

If you have any further questions, feel free to e-mail me at jdavis@gocsnw.com or you can call me at my home (972) 292-3369. I'm looking forward to meeting my new neighbors!

Jason Davis