Neil Sperry

Why is my lawn looking so drab? Answers to your most asked gardening questions

I do believe there’s an echo. I’m getting the same questions everywhere I go, so I thought I’d push ‘em out here as well. Maybe they’ve been things that were troubling you, too. Let’s take a look.

Why is my lawn looking so drab? I think I’ve fertilized it properly? Is there some disease or insect I need to know about?

To some degree the answer may depend on the type of lawngrass you have. St. Augustine has come out of a really bad summer for chinch bugs. Maybe not as bad as 2018, but many of our lawns have browned badly in the past month. Chinch bugs will always be in the sunniest parts of our yards, usually along walks and drives. However, there’s also the chance of leftover gray leaf spot and white grub worm damage.

Bermuda lawns seem to be struggling with grub worms more than usual. The grass is browned in large, irregular areas with undefined boundaries. When you pull on the worst of it, if grub worms are involved, the grass will be loose on top of the soil because the grubs will have devoured most of the roots. Dig down about 3 inches, and if you find four or five of the larvae per square foot of soil, those are your culprits.

They’re 3/4-inch long and 3/8-inch in diameter, white with brown heads. They’ll always be C-shaped, and they’ll have legs (as opposed to earthworms). If you find grubs, treat with an insecticide labeled for their control and water heavily immediately after you treat. But do check for their presence by tugging on the grass, then digging before you treat.

Why is the bark peeling off one side of my tree? The leaves on that side don’t look very good, either.

This is the result of sunscald damage to the west or south side of the trunk. It usually happens to young trees in the first three or four years after they are planted. It will be species with thin bark that are most commonly impacted. Shumard red oak, chinquapin oak, Chinese pistachio and red maple are at the top of that list.

What is this weed grass that just started sending up its seed heads all over my yard? It’s coming from the vacant lot next door.

You have King Ranch bluestem (also known as K.R. bluestem). It was introduced as a forage grass almost 100 years ago, and it has escaped those pastures. Now it’s a noxious weed in almost all of Texas and beyond. There is no effective weedkiller that will eliminate it without threatening your permanent lawngrass, and preemergent herbicides won’t help with it.

Your only means of dealing with it will be to spot-treat with a glyphosate herbicide, using care not to hit any more of your desirable turf than you have to, since glyphosates don’t discriminate. Mow frequently to keep the seed heads from developing.

I have several shrubs that have browned sections. They have just shown up in the past month. Boxwoods, Indian hawthorns and hollies are involved. Some of my nandinas are looking bad, too. What could the cause be?

Because there are four different types of plants involved you can pretty well rule out insects and diseases. Each pest problem tends to affect only one species. However, with this year turning so dry from late summer on, there has been a huge amount of damage and dieback done as homeowners let their plants get too dry.

It’s especially troublesome for folks with sprinkler systems. Hose-end sprinklers get set in different locations each time that we run them, so they water in different patterns. But sprinkler systems have definite dry spots that may never be reached by the irrigation, and that’s where plants die out. It can happen to one or two plants in a row when a head is blocked or broken.

What is this weed with the little white daisy-like flowers?

Roadside aster. In spite of its tiny leaves, it’s still classified as a “broadleafed” weed because of its flower type. Therefore, a broadleafed weedkiller containing 2,4-D will eliminate it. It’s best, however, to address it before it actually comes into bloom so that it can’t go quickly to seed. Next year try to spray by late summer. And, for what it’s worth, it’s a weed that only shows up where grass has been weakened by insufficient water or nutrition. Ramping up your feeding and watering schedule will probably help your turfgrass to crowd it out.

Why are my crape myrtles dropping so many leaves early, and why are they sticky?

The stickiness is secretion from insects. Coming from either crape myrtle aphids or bark scale, the honeydew coats leaves and stems (and surfaces beneath the crape myrtles). For whatever the reason, it causes leaves to fall prematurely. A few weeks after this all starts you’ll probably notice that black sooty mold will start to develop within the honeydew substrate.

To avoid the sooty mold you must eliminate the aphids or scale, and the best way to prevent their issues is to apply a systemic insecticide such as Imidacloprid as a soil drench around the plants in mid-May next year. You may want to take a soft sponge and a bucket of soapy water to swab off the trunks this fall, before the honeydew thickens and the sooty mold gets a strong start.

You can hear Neil Sperry on KLIF 570AM on Saturday afternoons 1-3 pm and on WBAP 820AM Sunday mornings 8-10 am. Join him at www.neilsperry.com and follow him on Facebook.

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