Localized Weather

Horticulture Hotline 07/22/19

By Bill Lamson-Scribner

Mosquitoes, roaches, fleas, flies, chinch bugs, army worms, wasps, spiders, spittlebugs, and mice have become much more visible with the hot weather. Localized pop up thunder storms (gray leaf spot) have dominated our weather, so there is no telling how much rain we are getting across the area as a whole.

With three Possum stores in the area, I get a regular dose of how crazy our weather is in the Lowcountry. Possum’s West (West Ashley) might get an inch of rain, Possum’s North (North Charleston) might get a “spit” and Possum’s East (Mt. Pleasant) nothing at all. It is amazing how the waterways affect the weather patterns.

The Lowcountry is one area that a rain gauge is a must. Rain gauges come in all shapes and sizes. Some are very expensive and record your rainfall, and others are very basic and are less than five dollars. You can make your own “rain gauge” very easily from anything that has an equal top diameter and bottom diameter. Soup cans, tuna fish cans, a coffee cup, or an empty can of canned possum (the other white meat) make great rain gauges. Be sure to place your rain gauge in an area where your house or trees are not going to skew your results.

Over the weekend, I was surveying the yard for potential mosquito breeding sites. We have this roll around basketball hoop in the driveway that requires water in the base to stabilize it. Of course someone lost the cap to the place you add water and now there is a great place for mosquitoes to breed. The slightest dent on my trash can lid also collects water where there were mosquito larva. I keep 3 sizes of measuring cups on a window sill near the hose where I mix up my “solutions” for killing weeds, fungus, and insects around the house. Rainwater had got in them, and you guessed it – more mosquito larvae. Tarp on my boat, magnolia leaves, five gallon bucket (s) ...Oh yeah, the rain gauge had mosquito larvae in it as well. Always empty out your rain gauge!

With all the insects that are active in the yard Cyonara Lawn and Garden Concentrate or RTS is an excellent product with a very broad label and a low price point. Cyonara is labeled to spray the outside of your house to keep roaches in check and even your vegetable garden, so you know it is safe. If you prefer organic products, EcoVia might be more to your liking.

Always read, understand and follow product label. The product label is a Federal Law.

Mid Summer Happenings In the Yard

Horticulture Hotline 07/15/19

By Bill Lamson-Scribner

As predictable as the Fourth of July fireworks, the army worm comes to attack the turf, leaving the scalped down – chowed down turf area. Athletic fields, golf courses, and home lawns lose the aesthetic value of the green grass, and the worms thin the canopy of the grass where weeds will move in if given a chance. Prostrate growing weeds like spurge, lespedeza and Virginia Buttonweed seem to come in the fastest.

What bothers me the most is you work all summer on your grass to have it looking nice, and once it starts to look good, fall army worms and then sod webworms attack the grass. Look for areas that appeared to have been mowed low and with a dull blade. You can see that the leaf blades have been chewed. Also thatch type debris will be churned up on the surface. Moths will fly low, during the day but mainly in the evening, dropping eggs across the lawn. Birds and low flying wasps are also predators of army worms.

Since army worms are in direct contact with the ground, they are very easy to control. Bug Blaster, Bifen, Sevin, Cyonara and Acephate will all put a hurting on army worms. Thuricide (Bt), EcoVia EC and Spinosad are organic products that will also work well if you get them while the worms are small. Since the population of worms is so high and hit so hard, keep your eye out for a second hatching.

For those of you with St. Augustine and Centipede, keep your eye out for the sod web worm. Watch for moths in your yard around dusk. If you begin to see a moth that gets out of the grass, flies for 6-10 feet then lands again (like a bobwhite quail for you bird hunters) you may want to consider using one of the above mentioned products. Usually sod web worms would not come out until September / October; however, with the crazy weather we are having, scouting for them could not hurt.

If your yard has thatch, drainage, or compaction issues, now is a great time to address these issues. At Possum’s we have a granular organic product (BGK 7500) that is full of microorganisms that are thatch eaters. Easy to apply with a fertilizer spreader and very effective. Some of the zoysia grass lawns really benefit from regular use of this product.

Gray leaf spot is still alive and doing well. With all the rain, fire ants are mounding up everywhere – be careful where you step! Figs are one of the fruit trees that do very well here. Be sure to wash your hands after picking. The latex sap in a fig has low doses of the same chemical that poison ivy has in it and can cause an allergic reaction in some people.

The Nasty Rascal the Chinch Bug is out and sucking the life out of the grass.

With all the rain, mosquitoes are out and biting, and the grass is growing like crazy. Scout around your yard for potential breeding sites for mosquitoes. It is amazing how many areas can hold enough water for a mosquito to breed.

Always read, understand and follow product label. The product label is a Federal Law.

Bill Lamson-Scribner can be reached during the week at Possum’s Landscape and Pest Control Supply. Possum’s has three locations 481 Long Point Rd in Mt. Pleasant (971-9601), 3325 Business Circle in North Charleston (760-2600), or 606 Dupont Rd, in Charleston (766-1511). Bring your questions to a Possum’s location, or visit us at http://www.possumsupply.com. You can also call in your questions to “ The Garden Clinic”, Saturdays from noon to 1:00, on 1250 WTMA  (The Big Talker). 

Gray Leaf Spot and a Myth

Horticulture Hotline 07/08/19

One Myth then on to the important information:

There is a way to stand upwind when using a pole saw and cutting branches overhead so the saw dust will not rain down on you. Fact: If you are a non-smoker, you have experienced this when talking to someone that is smoking. No matter where you stand, you are going to smell the cigarette smoke. The saw dust is the same way, getting in your eyes, face, I guess hair (I don’t have any), and on your clothes no matter where you stand.

Wasp, biting flies, flies, fire ants, fruit flies, and mosquitoes – Tis the season. It is scary the amount of fire ant mounds you see when you get into an area that is not managed for fire ants. We are getting reports of army worms so get ready for that battle again!

The rains and high tides have the mosquitoes are out in full force. Protect yourself! 

Between pop up thunderstorms, people going on vacation, and people just not mowing enough, gray leaf spot has exploded on St. Augustine grass. I am seeing gray leaf spot on Zoysia as well.

Gray leaf spot (Pyricularia grisea) goes with St. Augustine like grits go with shrimp! Or like chinch bugs go with St. Augustine! To battle gray leaf spot, you are best employing many cultural practices and using limited control products if necessary.

Gray leaf spot looks like someone burned or dripped acid on the leaves of the plant.  There are little oblong spots on the leaf.  Eventually, these spots grow together and the leaf blade dies.  Whole areas of your grass can disappear at once when these leaf blades die.

Culturally there are several things to do to minimize your problem with gray leaf spot.  This disease likes high humidity and excessive nitrogen fertilizer.  To help alleviate the high humidity, mow your grass to a level that seems abnormal to St. Augustine.  Try to get it down to 2 ½ - 3 inches depending on the variety of St. Augustine grass.  Also try to mow every 3 – 5 days with a bagger. I don’t usually recommend a bag, and if you don’t have one, just keep it mowed.  This mowing will help get sunlight down to the crown of the plant, drying the leaf blades as quickly as possible.

With mowing it is always hard to get someone to modify the frequency of cuts. “The landscaper only comes every 7 or 14 days” or “I mow every Saturday morning”, is what I usually hear. If you don’t want to cut it yourself (saving a trip to the gym and I have been told a cold beer or IPA is extra good after mowing) in between visits by the landscaper, maybe you could hire a neighborhood kid or your kid to just mow the grass. No edging, blowing or weeding, just a quick mow.

Another alternative to you mowing is applying a growth regulator to your turf. These products work great at slowing your turf’s growth rate. Growth regulators are used extensively on golf courses and athletic fields. Growth regulators do a great job of managing your turf’s growth rate on your home lawn as well.

Consider trimming trees or shrubs to increase air movement through your yard.

This fungus like most fungi likes hot humid weather.  Minimize the amount you water as much as possible.  Wait until your lawn is getting a blue/green color and your foot prints stay in the lawn after you walk across it before you water. Unfortunately, you can not control rainfall as easily. In the Lowcountry, afternoon thunderstorms are a way of life, so keep the grass mowed as low as you can so it will dry out quickly. 

Hold off of the nitrogen fertilizer until you can get this disease under control.  If you need some color, you could add a product like Possum’s Minors to give you some green without all the nitrogen. Watch starving your grass because a malnourished yard is more susceptible to disease. Very low rates of an organic fertilizer or cotton burr compost might help it recover.

At Possum’s, I know we have had several customers that swear they control this disease by using our wetting agent with biostimulants, cotton burr compost, and / or SeaHume along with the above cultural practices. You will need to water less with the use of these products, and wetting agents help keep the leaves on the grass plant dry. These products are not fungicides, but customers have seen a correlation of using them and having less disease issues.

If you have to resort to a control product, make sure the product is labeled for Pyricularia grisea.  There are many leaf spot diseases on labels of control products but only certain products work on gray leaf spot on St. Augustine and Zoysia. We had one customer come in that had been applying a product that controlled Drechslera spp. and Biopolaris spp. leaf spot; however, the product was not labeled for Pyricularia grisea (watch where you shop). 

Propiconazole and Azoxy are systemic products that you spray. Since this is a leaf spot fungus, the sprays seem to give good coverage over the leaf blade.  If you would rather use a granular product, Prophesy (same active as Propiconazole and Banner), Heritage Granular, Strobe Pro G, and Fame are granular systemic products that are absorbed through the roots and will do a good job for you.