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Ornamentals and Turf |
Now is the time that bagworms will be most easily noticed as the Leylands become defoliated. Unfortunately, the best time to treat was 6 to 8 weeks ago (see June 20, 2003 issue of the North Carolina Pest News). If the bags are still moving, Orthene might be your best recommendation. If they are not moving, it is too late for insecticide. Hand picking the bags still works where practical. Heavily defoliated Leylands do not re-foliate well. In that case, an application of Poulan or Husqvarna chain saws at the base of the plant will usually take care of the problem. For more information, see Ornamental and Turf Insect Note No. 81.
Though not an insect, it may be helpful to mention the tick-transporting, four-legged visitors to the garden and highway known as deer. Kim Powell of the Horticulture Science Department at North Carolina State University occasionally posts his list of regional landscape plants that deer like. It is included below with the addition of a few of our own.
Deer Problems in the Landscape
Plants Seldom Damaged: Botanical Name Common Name Berberis sp. Barberry Betula Birch Buddleia davidii Butterfly bush Buxus spp. Boxwood Cotinus coggygria Smoketree Cytisus scoparius Scotch Broom Elaeagnus angustifolia Russian Olive Ilex opaca American Holly Leucothoe sp. Leucothoe Picea pungens Norway Spruce Pieris japonica Japanese Pieris Cornus florida Flowering Dogwood Cornus kousa Kousa Dogwood Crataegus spp. Hawthorn Forsythia spp. Forsythia Gleditsia triacanthos Honey Locust Ilex cornuta Chinese Holly Ilex glabra Inkberry Juniperus spp. Juniper Kalmia latifolia Mountain Laurel Kerria japonica Japanese Kerria Ligustrum spp. Privet Mahonia spp. Mahonia Myrica cerifera Waxmyrtle Nandina domestica Nandina Nerium oleander Oleander Pinus spp. Pine Pittosporum tobira Pittosporum Podocarpus macrophyllus Podocarpus Pyracantha spp. Firethorn Robinia pseudocacia Black Locust Sassafras albidum Sassafras Syringa vulgaris Lilac Taxodium distichum Bald Cypress Thuja spp. Arborvitae Vinca minor Periwinkle Yucca spp. Yucca Vitex agnus-castus Chastetree Wisteria floribunda Japanese Wisteria Plants Occasionally Damaged: Botanical Name Common Name Acer griseum Paperbark Maple Acer rubrum Red Maple Acer saccharinum Silver Maple Acer saccharum Sugar Maple Amelanchier arborea Downy Serviceberry Campsis radicans Trumpet Creeper Chaenomeles speciosa Flowering Quince Cotinus coggygria Smoketree Cotoneaster spp. Cotoneaster Cryptomeria japonica Japanese Cedar Hibiscus syriacus Rose of Sharon Hydrangea paniculata Peegee Hydrangea Ilex crenata Japanese Holly Magnolia soulangiana Saucer Magnolia Parthenocissus quinquifolia Virginia Creeper Quercus spp. Oak Salix spp. Willow Spiraea (x) bumalda Anthony Waterer Spiraea Tsuga canadensis Eastern Hemlock Viburnum rhytidophyllum Leatherleaf Viburnum Weigela florida Old Fashioned Weigela Plants Frequently Damaged: Botanical Name Common Name Abies fraseri Fraser Fir Acer platanoides Norway Maple Cercis canadensis Redbud Clematis Clematis Cornus mas Corneliancherry Dogwood Euonymus alatus Winged Euonymus Euonymus fortunei Wintercreeper Hedera helix English Ivy Hemerocalus Daylily Hosta Hosta Malus spp. Apple Prunus spp. Cherries Pyrus calleryana "Bradford" Bradford Pear Rhododendron spp. Rhododendron/Azalea Rosa x hybrida Rose Sorbus aucuparia Mountain Ash Taxus cuspidata Japanese Yew Thuja occidentalis American Arborvitae
Last year about this time we saw an outbreak of larger elm leaf beetles. Elms are the major host for larger elm leaf beetles, but they sometimes feed on dogwoods, hazelnuts, pecans, river birches, plums, and hawthorns. The larger elm leaf beetle often suddenly appears in great numbers, does tremendous defoliation for a year or two and then disappears for an indefinite time (perhaps decades). Because defoliation is less damaging in the fall, the present damage less critical to the health of these trees. Sometimes groups of larvae can be seen on the soil surface beneath a tree. The beetles overwinter as grubs in the soil. In spring they pupate, and the new adults emerge in May. Adult larger elm leaf beetles chew holes in the leaves and lay their eggs on the leaves. The larvae hatch and skeletonize the leaves as they feed. There is one generation per year. Adults may survive throughout the summer. This insect can be controlled with various pesticides. Ornamentals and Turf Insect Information Note No. 24 contains additional suggestions for control of leaf-feeding beetles.
Tortoise beetles are small, round beetles that are more or less shaped like the body of a tortoise. The most attractive is the golden tortoise beetle that has a wonderful iridescent golden color when they are alive. The mottled tortoise beetle and Argus tortoise beetle feed on morningglory, sweetpotato and other related vines. These beetles overwinter as adults under bark or in leaf litter or other dry places. In the spring the beetles emerge and feed on weeds until morningglories or sweetpotatos come leaf out. Females deposit clusters of eggs under the leaves and grubs hatch a week or so later. Several generations occur each year. Hand picking beetles or Sevin or other contact insecticide should provide adequate control.
Employment and program opportunities are offered to all people regardless of race, color, national origin, sex, age or disability. North Carolina State University, North Carolina A&T State University, U.S. Department of Agriculture, and local governments cooperating.
Last modified on August 4, 2003 by Stephen J. Toth, Jr.
