There is a new granular fungicide for homeowners that works almost as good as Heritage Granular, but costs a little less. It is call Disarm G. It is in the same fungicide family as Heritage G. (Strobulins). Great fungicide, but it still ain’t cheap!!!!!!! Check Dickens Supply or Sigma Organics for this product.
Wednesday, June 10, 2009
Yellow Nutsedge – A warm season perennial plant that looks like yellow grass, but is actually a sedge. It emerges in poorly drained areas or areas that irrigate too frequently!!! Light frequent irrigation makes nutsedge problems 90% worse than deep, infrequent irrigation!! If you get several thunderstorms during May, nutsedge is inevitable. Since it is a perennial, crabgrass pre-emergent has no effect on nutsedge. There are two decent herbicides that (IF APPLIED PROPERLY) can control nutsedge. They are Sedgehammer or Dismiss. Dismiss is the newer and better herbicide. It controls nutsedge often with one application where as Sedgehammer always takes at least two apps. Make sure to follow the label with all herbicides! Dismiss will stunt desirable grasses for up to a year or kill them if over applied. We spot treat for nutsedge during third app each year and every time we apply preventative fungicide. Nutsedge tends to keep germinating in the same spots every year, all summer long. DO NOT pull it out of the ground. This often leaves the “nut” in the soil and causes rapid proliferation of more sedge. it is like pruning a shrub, it stimulates rapid growth!! if you do pull it, make sure you get the whole plant!!!
These weeds are mostly mistaken for crabgrass. They look like crabgrass on steroids. They are in fact quite different than crabgrass! They both are warm season perennials and crabgrass is a summer annual. This means crabgrass dies every fall after the first frost. Johnsongrass and Dallisgrass do not die after the first frost, however, the top foliage disappears after the first frost. When April arrives, the plants put out new top growth from the rhizome underground. The top left photo, shows a johnsongrass rhizome. Therefore, crabgrass pre-emergent does nothing to deter these perennial grasses. Pre-emergent only keeps annual plants that germinate from seed(crabgrass) from emerging. There is NO selective herbicide that will kill these grasses without killing your desirable grasses. Therefore, the best time to control these grasses is at the end of the summer, right before overseeding time. Roundup or Fusilade should be applied twice, ten days apart for best results. The BEST control method is a shovel!! The rhizome is very difficult to kill, even with Roundup or Fusilade. Therefore, digging them out is the best method. If you have several of these plants in close proximity, they are most likely connected by the rhizome underground. If you spray 10 of these plants with either Roundup or Fusilade, 7 will not return in the same spot the following April, but up to three may remain. If you choose to spray these grasses instead of digging them up, be prepared to take 3 summers for 100% control. What a pain!!
Why do I get these??? Surface soil moisture is the key. A poorly drained soil or light, frequent irrigation makes these grasses go crazy. See irr 101 to correct bad irr habits. To improve drainage, aerate every fall. We typically treat these grasses during 4th app in late July or August. If you do not want the dead brown spots that accompany the killing of these grasses, please let us know prior to 4th app!!!
Thursday, June 4, 2009
“Brown Patch” fungus is the number one fungus problem on cool season lawns in TN!!!!!!!!!
Causes: Heat + Humidity+Moist leaves. It is very similar to athletes foot on grass! It generally begins about late May and can be active thru late August. It requires 60 degree nights to remain active. Right now, in early June 09, it is in high gear!!!
Symptoms: Brown circles from coffee cup size to over three feet in diameter, with most common size about dinner plate size. When observed early in the morning, before dew dries, a grey”smoke” ring will appear in the outer rim of the circle. This ring means the fungus is actively spreading and damaging turf.
Chemical control – Fungicide is expensive! It requires half of the fungicide to prevent fungus as it does to stop it. Therefore, it is smarter to prevent it with a systemic fungicide three times each summer if you don’t want to get damage from the disease. It generally does not kill the turf, but the circles of ugly will remain until fall if not treated.
Cultural Control – Back off on quick release nitrogen! Lawns that are juicy green going into the summer are usually fertilized with large amounts of quick release nitrogen. Succulent, dark green leaves are soft and easy for the fungus to penetrate. Therefore, we switch to organic, balanced fertilization during the summer and back off of the deep green we maintain in spring. Water deeply and infrequently. The number one mistake homeowners make is to water their lawns when air temps are above 75 degrees. Remember, leaf, NOT soil moisture is the main ingredient needed for fungus development. If humidity is really high, that alone is enough moisture alone to ignite the fungus.
General mis-information: “I never got “Brown Patch” when I had weeds, bermuda, and other stuff in my lawn”. I have heard this many times, and it is true. It is not natural to grow a mono stand of cool season grasses, with no weeds and keep it green during high temps. Therefore, if you stop fertilizing, let the weeds and bermuda take over, and generally let nature put what nature wants in your lawn, you will never have a “Brown Patch” problem. However, most people reading this want nice looking lawns. It’s just part of the price we pay for trying to outsmart nature. “If we don’t fertilize, will we still get “Brown Patch”? Not as much, but your grass will be high yellow and “Dollar Spot” fungus will be your new problem. It attacks under fertilized turf. Then you will have ugly yellow turf with brown spots all in it.
Helpful Info: “Can I treat it myself and save some money”? You can treat it yourself, but won’t save much money. There is only one granular fungicide that works for 28 days. PERIOD! That is Heritage granular fungicide. All the other granulars cost a little less, but only last 10-14days. You will have to use the cheaper ones twice to get full recovery. Heritage granular fungicide is availabe at the “vendors I like” section on right side of this page. Expect Heritage granular fungicide to cost a minimum of $6.00/1000sqft at the PREVENTATIVE rate. $12.00/1000sq ft at the curative rate.
Irrigation 101: How to water your lawn
Most people with irrigation systems do not understand the best way to program their irrigation system. The tips I offer here will help you figure out how to set your irrigation system, regardless of the type. Turfgrass uses the most water during times of high heat and low humidity. This tends to be during late April, early May, and from August through October.
Turfgrass uses water to cool itself very similar to how a car uses a water pump. Water is pulled in through the roots and exits through the leaves. When the humidity is below 70%, water is rapidly pulled throughout the plant and into the atmosphere. If enough water is available, the
grass will stay green and healthy. If you have a week with no rain, temps in the upper 70s to upper 80s and humidity below 70%, your lawn will use almost 1 .5 inches of water. These weeks are rare, but do occur during the months listed above. When temps are high and the humidity is high, your lawn will use only about 1 inch per week. When humidity levels are high, the turfgrass can not pump the water effectively because the atmosphere is already moist. This is typically when you start seeing fungus develop. My best yards water each zone just two days a week. They apply half an inch to each zone twice weekly. In order to figure out how much water your zones are putting out, place coffee cups or tuna cans in the lawn. Make sure these are flat on the bottom with vertical sides. Let the system run however you have it set currently. Stick a ruler in the can to determine the amount of water you are applying for the amount of time you have the stations set. Adjust the time as necessary to catch one half an inch each time the system runs. Set the system to water twice weekly during most of the year.
During the times when humidity drops, you may have to add the third day to keep up. We use irrigation to supplement rainfall. When nature provides a heavy rain, the water seeps through the profile and the grass responds. The roots of the turfgrass grow downward towards the seeping water. Therefore, the roots grow deep and strong. People who water for a few minutes, several times a week, encourage the roots to stay near the surface because the roots get frequent light water on a consistent basis. Therefore they create “sissy grass", that has a wimpy root system. When the temps climb into the 90s for a few days, the sissy grass wilts quickly. When the grass wilts or dies, weeds take its place. The second reason for watering deeply and infrequently is as follows. Light, frequent waterings, keep the soil surface damp. This encourages weeds like nutsedge, crabgrass, johnsongrass, and dallisgrass. The turfgrass gets ZERO benefit from a wet soil surface. Weeds however, love it. We want to encourage the turfgrass while discouraging weeds. Changing your irrigation to deeply and infrequently will reduce weed germination up to 90%. Please try to adjust your system to more closely resemble the deep and infrequent system. If you have a large system with many zones, you may need to water half your zones one night and the other half the next in order to run each zone long enough to apply one half
an inch per watering.
What time should I water?
The best time to water is from midnight to 7:00am. The wives tale of "watering at night causes fungus" is just that, a wives tale. Dew forms on turfgrass each night and keeps the leaves wet until the sun dries them the next morning. Turfgrass also excretes guttation water during the night. Guttation water is high in sugars and excellent for feeding fungal spores. Therefore, irrigation at night washes off guttation water, which is a good thing. Turfgrass fungus occurs more when the DURATION of leaf wetness increases than when the total amount increases. Water left on the leaf blades when soil temps are high is like gas on a fire for fungus. Therefore, we need to stop watering by 7:00am so that the grass blades will dry by the same time they would if it were just dew on the blades. High air temps + high leaf moisture = fungus development.
How can I tell if lawn is getting enough water?
Take a phillips head screwdriver and stick it in the ground. You should be able to push it in the ground to the handle. If you can, and the screwdriver does not come out of the ground muddy, your soil is perfect. If it slides in very easy and comes out muddy, reduce the duration of H20. If you have to stand on the screwdriver to get it to the handle, turn up the duration of H20.
Please call me with any questions about your irrigation habits. With your help, we can give you the healthy, weed free turf you are looking for. Without your help, we can't make vour lawn the best it can be.
Tuesday, June 2, 2009
Moles are going crazy in 2009. The theory is a wet spring has caused a large survival of spring litters. How to get rid of them?? Call Keith Burgess 496-7004. His company is Affordable Wildlife Services. It is a flat fee service for a given amount of time. You choose how long you want his services. Step#2 is have us do a turfgrass insect control to eliminate their food and make your lawn less desirable to set up shop in for next year. Most people have been told moles only eat grubs, when in fact earthworms make up a larger percentage of their diet than grub worms. It takes a dual approach to accomplish mole control. Just because we get rid of all their food, it doesn’t keep them from looking. They are quite stupid! One more thing you might try if you don’t want to go the trapping route. HEAVYDUTY MOLE CHASERS. You can buy them online at Amazon.com or several other places. I have not personally tried them, but a friend in the business says he is having great success with them. Their is a strategy to using them. Call me for details! 394-6867. Sincerely, Robert Stroud Turf Doctor