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Seal cracks, vacuum to get rid of Asian lady beetles

By Neil Sperry | Published Wednesday, December 13, 2017

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Dear Neil: We are having seemingly unlimited numbers of brownish ladybugs flying around inside our house. What are these nuisances, and how can we get rid of them? Or will they leave on their own?

These are the multicolored Asian lady beetles (ladybugs). They were released by the USDA 30 to 40 years ago in an attempt to control aphids and scale insects. However, they are attracted to bright light and light-colored walls. They congregate in the warmth of attics, walls and crawl spaces and can emit a foul odor. University entomologists recommend sealing cracks where they may be gaining entrance. Once they have invaded, it is recommended that you vacuum to remove them. Try not to handle them, but when you must, wash your hands immediately. They can cause allergic sinus irritations. The use of insecticides for their control indoors is usually not recommended, especially when it might mean that large numbers of them would die en masse.

Dear Neil: A friend has Desperado sage plants in her native plant landscape in Wichita Falls. Big sections of several of them are dying out, and they have been for some time. They have been watered fairly well, both from rain and irrigation. What might cause them to be dying in parts?

It could be from poor drainage if they have been kept very wet for prolonged periods, but most of the ones I’ve seen struggling in the northern half of the state this year have been suffering leftover damage from the really cold spell of last January. It took a while to show its effects on some plants, but my bet is that the past cold would have been the cause.

Dear Neil: Our beautiful chrysanthemum went from gorgeous to completely trashed overnight. What is the pest in my photo, and what do I do with the plant and the insects?

Those are spotted cucumber beetles, and you’re right about the fact that they ruined your mums. (You thumbnail photo is low-resolution. To describe, they look like elongated green ladybugs.) Cut your plants back to within an inch of the soil line (which you should do at the end of the blooming season anyway). Treat the top of the ground with Sevin or Permethrin to kill the existing bugs, then again in the spring if you see any signs of more beetles developing. Don’t let them get out of hand, and treat before they can feed on the flowers.

Dear Neil: Our Little Gem southern magnolia developed scale insects last year. We had it treated four consecutive months, but now the scales are coming back. What can we do to eliminate them? We don’t want to eradicate the tree, just the scales.

Honestly, you will rarely see scale insects attacking magnolias. I don’t recall being asked about them before, but your small photo is ample proof. I don’t think this will be a huge issue over time for you. However, horticultural oil (“dormant” oil) applied over the winter is a treatment you can make yourself. You could also use a soil drench of the systemic insecticide Imidacloprid in late May, as the new leaves are emerging. Rake and dispose of all old leaves as they fall from late April into June. The scales persist on them from one generation to the next.

Dear Neil: I have never grown purpleheart before, but it has done really well for me this year. I am told that it is winter-hardy. Will it come back in the spring? My other wandering Jew plants never have.

It’s the one type out of that group that is winter-hardy. It will freeze to the ground, but if you leave it undisturbed, it will sprout out again in the spring. Your planting should get thicker and thicker over that time. It’s a great perennial that many of us have fallen in love with.

Dear Neil: Are there any types of tree leaves we shouldn’t use in our compost pile? We have primarily elms in our yard, but I’ve collected upwards of 20 bags from neighbors and I’m ready to grind them and put them into our compost.

Great work! That’s a wonderful way to build up organic matter for your own garden, and it also saves valuable landfill space. Some people will tell you that certain species (oaks, pecans, walnuts, cedars, etc.) have oils that are not good for plant growth, but that’s vastly overstated in my opinion. In fact, oaks and pecans make up the bulk of our own compost at our house, and a big part of our landscape is beneath eastern redcedars (growing in years of cast needles). The secret is in using these things in moderation and in giving them time to decay before you start planting in them. Your elm leaves will be a great mixer with oak and pecan leaves. Shred all of them to speed the decay, and mix in 1 inch of topsoil or mature compost to introduce the microorganisms needed to get it all started. You’ll be in great shape.

Have a question you’d like Neil to consider? Mail it to him in care of the Wise County Messenger, P.O. Box 149, Decatur, TX 76234 or email him at mailbag@sperrygardens.com. Neil regrets that he cannot reply to questions individually.

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