KNOWitall
Ask the Expert By Debra Ricigliano
Removing or Replanting a Fallen Leyland Cypress
Q: We have a Leyland Cypress that fell over from having heavy snow on the branches. The roots are still mostly in the ground except for one side of the tree. My question is, can it be pushed upright again and survive? Or should we remove it and replant? A: Unfortunately, what happened to your Leyland Cypress is a common problem. Its root system is relatively shallow and small for its ultimate size. Replanting the tree would be fruitless because it probably would not reroot. The tree would be unstable even if it is staked up and supported. Replacing it is your best option. Japanese cryptomeria (Cryptomeria japonica), American holly (Ilex opaca), Eastern red cedar (Juniperus virginiana), and Arborvitae ‘Green Giant’ (Thuja plicata ‘Green Giant’) are replacement tree suggestions.
Diagnosing a Mysterious White Substance on Crapemyrtle Bark
Q: I planted a crapemyrtle last summer that bloomed beautifully. After it lost its leaves, I noticed this white mold or fungus on the bark. The limbs are covered. What is it and what should I do? A: A relatively new insect pest of crapemyrtles has been showing up in local landscapes. It is a non-native type of soft scale and is called crapemyrtle bark scale. It’s also possible to find leaves covered in black sooty mold during the growing season. Soft scales are sucking insects that exude honeydew as they feed. Sooty mold, a type of fungus, grows on top of the sticky honeydew. Since this scale species is new to the area, we do not know much about its life cycle making information about management challenging. However, it is being studied. Several generations are likely to occur here; between two and four is the current belief. The sizes of crapemyrtles vary from small, 2- to 3-feet shrubs to 20- to 30feet trees. Thorough coverage of the bark and trunk with a dormant rate of 22
WASHINGTON GARDENER
FEBRUARY 2022
Crapemyrtle bark scale. Photo: Jim Robbins, University of Arkansas CES, Bugwood.org.
horticultural oil with follow-up sprays during the season using the summer rate of oil is recommended. If spraying above your head is necessary, hire a professional applicator who works for a landscape company. Licensed applicators also have access to growth regulators and systemics for treatment. For detailed information, go to the HGIC website page about this pest, https:// extension.umd.edu/resource/crapemyrtle-bark-scale-new-problem-homelandscapes.
Is Reducing Lawn Areas a Fad or Here to Stay?
Q: What’s all the buzz about replacing or reducing lawns? Are there really any good alternatives? A: As more of our clients are concerned about climate change and desire to make changes they can accomplish in their own yards, we have suggestions for lawn alternatives. Lawns do have their place in a landscape for play areas and defining garden beds or walkways, but they are thirsty, ecological deserts that require intensive management to “look good.” An easy way to start is by replacing turfgrass in areas of your property where it does not grow well, like in the shade or around trees, and plant a shade-loving native groundcover like wild ginger (Asarum canadense) or crested iris (Iris cristata). Install a rain garden in wet, soggy areas.
Another step is enlarging your garden beds to replace a section of your lawn with native plants or shrubs, and if you have the room, plant a tree. On large properties, maintain the lawn close to the house and allow the rest of the lawn to be more of a natural area. If neighborhood constraints prevent you from having a no-mow or natural area, at least leave the dandelions, wild violets, and clover for pollinators. Since this type of conversion is gaining in popularity, there are many resources you can turn to for help. These ideas are just the beginning of supporting a healthier watershed and environment. Send any questions you may have to our website listed below. o Debra Ricigliano is a Certified Professional Horticulturist who has worked as a horticulture consultant for the University of Maryland Extension Home and Garden Information Center since 1997. She is a graduate of the Institute of Applied Agriculture at UMCP. To ask a gardening or pest question, go to http://extension.umd.edu/hgic and scroll to “connect with us.” Digital photos can be attached.
