Mold on Chinese tallow an ominous sign
Q: Last winter’s cold almost killed my Chinese tallow tree. I had a tree service company remove all the dead wood three weeks ago. I’ve been removing the suckers from the base of the tree and from some of the limbs through the season, but now I’m wondering what this white growth might be.
A: You would need a mycologist to give you a specific identification of this fungus, but it’s a saprophyte, meaning that it’s growing off decaying wood. My concern is that there is an issue within the trunk of the tree at that point. Treating this on the surface won’t be of much help.
Tallows were badly damaged and even killed all across Texas, particularly in the northern twothirds of their range by that cold. For anyone interested in saving a tallow, the basal sprouts might have been a better way. I fear you’re going to end up having to replace the tree anyway — that more branches will die back. That’s based on what I’ve been seeing this summer and fall in many parts of Texas.
I’m sorry for that bad news. Hopefully I’m wrong in your case.
Q: My friend has a large bougainvillea growing in a bed near her front door on the Gulf Coast. She had another bougainvillea there before, but last winter killed it. Her new plant has grown well this year. She’s wondering how best to protect it if it gets really cold. Should she prune it and cover it, or just cover it? It would be so difficult to cover as large as it is, but we’ve heard that pruning should be left until spring.
A: February’s cold isn’t likely to be repeated for many years, even decades. If her area is warm enough that prior bougainvilleas have survived, this one probably will, too. I would wait until it was necessary to do anything. However, pruning it to keep it somewhat in bounds might be in order toward the end of the winter.
Q: How well will Dura Heat river birch do in Texas? I bought one in mid-october. It had spots all over its leaves. The garden center owner said I could return it if the leaf spot proved to be impossible to control. I sprayed it with a biofungicide and then seaweed extract, but now I’m wondering if I should return it and look for a better Dura Heat birch. It’s going into a bed where Nellie R. Stevens hollies have drowned. I thought it would be a better choice.
A: This doesn’t look like a leaf spot, and if it is, there’s no point in treating for it this late in the year. Birch trees lose their leaves with the first frost anyway.
Dura Heat river birch theoretically holds up to summer weather better than the species. However, all birch trees struggle with hot weather in Texas. The farther west of the Piney Woods you get, the less likely they are to succeed. This looks more like heat and low humidity damage than anything else.
And as far as Nellie R. Stevens hollies are concerned, they are my all-time favorite large shrubs. I have several dozen in various parts of our rural landscape. Several are in very low areas where they grow in a heavy clay soil. When we get prolonged rainy weather, the water table becomes very high, yet they hold up perfectly. I have yet to see one die from waterlogged soils, but I’ve seen hundreds die when folks have let them get too dry between waterings.
I would really try to figure a way to improve the drainage in that bed and then go back in with Nelle R. Stevens hollies.
Q: This vigorous, twining vine appeared in one of our beds. It’s nothing we remember planting. Can you identify it? Is it edible, or is it poisonous?
A: Malabar spinach (Basella alba). It’s a vigorous Asian vine that also is quite pretty. Yes, it’s edible. You can Google it for a lot more information.
Q: I have two weeping yaupon hollies. When I bought them, both had red berries. For the past two years they have bloomed, but no fruit. Can you tell me why?
A: They weren’t being pollinated, or a late frost or freeze got the immature berries. It pretty much has to be one or the other if they had flowers.
All weeping yaupons are female plants. Therefore, each plant is capable of producing fruit if there is a male, pollen-producing plant nearby and if there is good bee activity while they are blooming. I wouldn’t be terribly concerned with 2021 because of the extremely cold weather that came so late in the winter, just before bloom time. Most of our hollies have been bashful about producing fruit this year.
If your plants have been healthy and have grown well otherwise, they will start producing fruit each year before long.
Q: I recently read that we should not rake leaves but leave them on the lawn instead. That way we would not fill our landfills with them but return the nutrients and organic matter to the soil. It seems like too much of a good thing, considering how many leaves trees like live oaks produce. Please advise.
A: I have no problem using a mulching mower 49 or 50 weeks out of the year. However, for those two or three weeks when leaf fall is at its greatest, I agree with you. It is too much organic matter to return in one short time. At that time I think it is best to run them through the mulching mower, collect them and put them into the compost pile, or use them as a mulch beneath shrubs or around perennials. To be honest, I do that all year.