Monday, August 10, 2020

Late Summer - Time to Get Ready For Fall


Horticulture Hotline 08/10/20
By Bill Lamson-Scribner

Army worms, sod webworms, mosquitoes, gray leaf spot, chinch bugs, nutrient deficiencies, weeds, heat, vines, fire ants, lace bugs, rats, flies, fleas, termites and roaches seem to be dominating the question counters at the three Possum’s.

Army worms will affect the aesthetic value of the green grass on athletic fields, golf courses, and home lawns, and the worms thin the canopy of the grass Prostrate growing weeds like spurge, lespedeza and Virginia Buttonweed seem to come in the fastest.

The army worm female can lay over 1000 eggs. She usually lays them in groups of 50 to several 100. The eggs hatch in 2 to 10 days. The larva then eats your grass for 14 to 21 days before they return to the soil and pupate. New egg laying moths emerge in 10 – 14 days. With several hundred larvae eating your grass at once, you can imagine how quick army worms can ruin your grass.

What bothers me the most is you work all summer on your grass to have it looking nice, and once it starts to slow down for the winter, 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. 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, zoysia, bermuda, bahia or 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.

We just had a wind event that came up from the south. The moths of these worms will often catch a ride on wind currents from areas that they are active year-round. Watering first to bring the worms to the surface and applying products in the evening when the larvae are about to feed, will often help your success depending on the product.

Now is the time to put out preemerge products in the lawn and beds to prevent those small seeded annual weeds. Henbit, chickweed, Poa annua (annual bluegrass), cudweed and lawn burweed are a few of the winter weeds that would like to occupy your lawn and flower beds. Poa annua (the green grass that is very visible in February and March) and lawn burweed (the prostrate growing weed that develops a sticker) are usually the most hated of the winter weeds. Some people use profanity while describing them at the counter of Possum’s! 

If your yard has thatch, drainage, or compaction issues, now is a great time to aerate your lawn (and beds where possible) before you apply your fall preemerge. Aeration is a great cultural practice, which will among other things help your roots grow throughout the winter giving you a head start for the spring. 

The “nasty rascal the chinch bug” is still sucking the life out of many lawns. Gray leaf spot is still alive and doing well. With the rain, fire ants are mounding up everywhere – be careful where you step! Mosquitoes are out and biting especially in the evening. Flies are causing many backyard grill masters grief.

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). Saturday's show is replayed Sunday from 11:00 - Noon.


Monday, July 27, 2020

Red Imported Fire Ant


Horticulture Hotline 07/27/20
  Bill Lamson-Scribner

Ok. After a little diversion due to environmental conditions, I’m back to the stinging, biting insects. That is the good thing about writing a local column, I can write about issues that are right here in the Lowcountry. With the way things are going, I’m sure an article about armyworms is next.

Believe it or not….fire ants are very easy to kill and manage!  You will not eradicate them; however, you can manage them.  There are many products on the market that will kill fire ants.  Some products are more economical if you have large areas to treat, others do a great job at just killing fire ants, and other products will kill other insects as well as fire ants. 

If you have a large area (16 or more acres) the bait products are very economical (less than 15 dollars an acre) and effective.  If you have a smaller area, you can treat one acre for less than 25.00.  Depending on the amount of rain that we get this summer and fall, you may have to retreat in six months if you notice any activity.  Some bait products are designed to kill fire ants as well as other ants that are in your yard (carpenter ants, argentine ants).

It is best to spread the bait over the entire area once the soil surface temperature reaches 70 degrees.  You also want to keep the bait dry for 24 hours, so watch the forecast.  The ants must be actively foraging to pick up the bait.  You can determine this by throwing some greasy potato chips or some of the bait itself on the ground and come back in 10 minutes to one half hour and see if the ants are carrying away the bait or chips.  The bait products advantage is that it is low cost and effective.

Products containing bifenthrin (Bug Blaster) will give you long term control of ants as well.  With Bug Blaster you don’t need to worry about rain, or whether the ants are foraging.  Dr. Tim Davis noted that he was getting at least eight months of control with bifenthrin.  Bifenthrin products are best applied over the entire yard.  Bug Blaster’s biggest advantage is that not only will you kill fire ants, but you will kill army worms, sod web worms, fleas, chinch bugs, ticks (Lime disease), mole crickets, and many others. 

There are many choices on the market; the biggest thing is determining which product fits your needs. Extinguish Plus and Advion Fire Ant Bait are two of my favorite bait products. Bug Blaster is a good contact product. Notice I only recommend treating the entire yard instead of chasing them around with mound treatments (stinky,white powder). 
When it has been hot and dry, fire ants can be tricky and not so visible because their mound is underground. Don’t be fooled! They still bite!

Do you have areas of your lawn that look like someone mowed it with a dull mower blade running at half speed? Do blades of your grass have bite marks eaten out of them? Do you have army worms or sod web worms? Bug Blaster will get them too.

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). The Horticulture Hotline is available 24 / 7 at possumsupply.com. 

Monday, July 20, 2020

Weather Related Disease - Hot and Rainy


Horticulture Hotline 07/20/20
By Bill Lamson-Scribner

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. Army worms are munching on lawns so get ready for that battle again!

The rains and high tides have the mosquitoes are out in full force. The sun is full force – hydrate and 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 string trimming, 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). 

Strobe Pro G, Heritage and Fame are granular systemic products that are absorbed through the roots and will do a good job for you.

Always read and follow product label.