Neil Sperry's Mailbag

From your photos it is pretty evident that they’re in heavy shade. Move some of them to a full-sun location and see if they don’t do better.

New red oaks must be protected against sunscald and borer invasion for their first year or two in their new homes. The only reliable way to do so is to wrap their trunks with special paper tree wrap from the nursery or hardware store. Without the wrapping, the results will be exactly as you described.

You may end up losing the one tree. It sounds like the other one will be fine.

Those were last year’s leaves. Any evergreen plant, hollies included, has to shed its old growth at some point. Most do so as the new growth emerges in the spring. Your plants will be fine.

I normally don’t do plant identifications here since they are of interest only to the one person, but yours is a common question. Indeed, this is a Shumard red oak, and what you’re seeing is insect galls. They’re the result of the adult insect stinging the twigs and laying her eggs. Larva develop within the galls. They do no major damage, and there is no control for them.

Dwarf burford hollies would eventually get there, and they would be great choices. Willowleaf hollies would grow to that size more quickly, although you might have to trim them a couple of times each season to keep them that short and that narrow. They normally grow to 7 or 8 feet tall and 5 feet wide.

Pillbugs normally don’t do a lot of harm to our landscapes and gardens except for new seedlings and transplants. I’ve always had excellent luck with Sevin dust. I apply it to the soil surface alongside and around the plants. Actually, I’m doing so for snails and slugs, but it has also worked on pillbugs. I don’t know that I have ever had to treat specifically for the pillbugs themselves.

That climate is not the ally of a moss gardener. Moss grows luxuriantly in Texas during cool winter and early spring weather. It’s especially common in the eastern half of the state where the humidity is usually high.

However, once it turns hot and dry, moss goes completely dormant and turns insipid greenish-brown. You won’t see the same kind of moss gardens in Texas that you were used to in the Pacific Northwest. That’s just a completely different kind of climate. Concentrate, instead of some of the lowest sedums, dwarf mondograss and other ultra-low groundcovers.

Cottonwood borers are a horrible problem with willows (also cottonwoods and poplars), enough so that the average life expectancy of a weeping willow in a standard landscape setting is probably only 5 to 7 years. Most other willows would be about the same.

Willows can be rooted in water by using stem cuttings, but the pertinent question probably should be: would you show your granddaughter a better example if you bought an oak of an adapted species to emphasize quality and durability of trees? If I were giving a tree to one of my grandkids, it would definitely be an oak.

First of all, the assumption that grasses don’t carry their own share of the load in our landscapes is not correct. It would be a sad landscaping day if we didn’t have turf for recreational spaces, for its cooling effect, for erosion control and for simply unifying our garden designs. And, “native” isn’t always synonymous with water-conserving. I offer cottonwoods and willows as examples. Johnsongrass is native, yet it guzzles the water.

Common bermudagrass is a great compromise: a grass that is drought-tolerant, but also one that’s good-looking and durable. I will acknowledge that we over-water and over-feed our lawns, but we shouldn’t over-correct as we strive to right our ways.

Even with large trees in deep soils, 90 percent of their roots will be in the top foot of soil. After all, that’s where rainfall hits, so they’re there to compete. We must never add more than one inch of soil over a tree’s root system. It will compact and drive available oxygen out of the soil. As for the bermudagrass, there is no easy way to eliminate it from liriope and mondograss. If it were mine, I would probably dig it all up, then carefully work through the plants to remove the grass. I would work organic matter into the soil and replant. However, if oak roots were in this same area, I would probably try to figure some attractive way of discouraging their growth. I might put a layer of roll-type mulch down, then cover it with attractive, small river rock. I’d figure a way of including large, decorative pots in the area for added interest. Take photos to a Master Certified Nursery Professional for addition suggestions.

Neil Sperry
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