Fire blight is caused by bacteria that are particularly active in warm, moist weather. The Clemson Cooperative Extension notes that hollies succumb to fungal root rots when planted on poorly draining soil or when overly mulched. suggestions. Young leaves formed during cool, damp weather are damaged easily if exposed to hot, dry, windy weather. Why Are the Leaves Turning Brown on Holly Bushes? Being able to identify the types of disease that may cause the tree to become damaged or suffer a premature death will help a holly tree owner apply a fix that will save the tree and prolong its life. In the autumn, a flat black, cushion-shaped fungal structure forms beneath the leaf surface. Planting your holly in well-drained raised beds and removing infected plants will help curb the disease. All information is provided "AS IS." Spray late in the day and when no rainfall is expected within 24 hours. Holly trees or shrubs are a common plant that produces holly leaves that are commonly found in homes during the Christmas holiday. Clarkson earned a Bachelor of Arts in journalism from the University of Florida. There are two generations of two-lined spittlebugs in South Carolina, and this insect overwinters as eggs (generally laid in turfgrass). An insecticidal spray containing one of the following active ingredients will reduce damage by adult spittlebugs: acephate, bifenthrin, cyfluthrin, cyhalothrin, or permethrin. Size: 3 to 6 ft. (1 1.8 m) tall and 8 to 15 ft. (2.4 4.5 m) wide, depending on the cultivar. Cankers cause spots on the stems, which undetected will cause the plant to die. Tar Spot Tar spot is a fungal infection that appears on the holly tree. See Table 1 for examples of products containing these active ingredients. Nellie Stevens holly (Ilex Nellie Stevens). Both of these evergreen holly trees are famous for their shiny, jagged leaves and winter red berries. Looking up close, pictures of male holly plant flowers show they have longer stamens than female holly flowers. East Palatka Holly (Jlg X attenuata) is often particularly hard hit. The result is a slow decline characterized by reduced vigor, yellowing or bronzing of the leaves, stem dieback, failure to respond to water or fertilizer ,and eventual death. Identifying and Treating Harmful Dogwood Diseases, Do Not Sell or Share My Personal Information. The best defense against canker is prevention. For the best experience on our site, be sure to turn on Javascript in your browser. Find more gardening information on Gardening Know How: Keep up to date with all that's happening in and around the garden. Holly pit scale (Asterolecanium puteanum) is a pest on American, Burford, Japanese, and Yaupon hollies. Dinotefuran may move into shrubs more quickly than imidacloprid for faster pest control. Larvae emerge in spring to continue the cycle. Avoid the use of spray pesticides (both insecticides and fungicides), as well as soil-applied, systemic insecticides unless absolutely necessary. Purple Leaf Scorch: The most common leaf discoloration is a purplish blotch due to the environment rather than a fungus. Control: Most canker-causing fungi infect stressed or injured trees. The Eagleston holly has a pyramidal crown with evergreen foliage that looks attractive all year long. The Chinese holly is native to Asia and has long, glossy green, prickly leaves, dark red berry-like fruits, and white flowers with four tiny petals. See Table 1 for examples of products containing the active ingredient. verticillata, zones 3-9) hollies. Typically, yellowing of the leaves (particularly at the shoot tips), early leaf drop, slowed plant growth, and twig dieback are seen at early stages of the disease. Apply all chemicals according to directions on the label. The symptoms of this disease and black root rot are similar. This disease manifests itself with tan or darker brown spots on the the leaves. Most diseases for hollies are caused by the environment or location where the plant is. Size: 40 to 60 ft. (12 18 m) high and up to 20 ft. (6 m) wide. However, holly bushes typically grow up to 6 ft. (1.8 m) tall and are multi-stemmed plants. She also writes about landlord and tenant laws. Diseased stems and branches become swollen and enlarged, and an excessive number of shoots will sprout vertically from the infected areas. Prevention & Treatment: Presently, there are no effective chemicals registered for the control of nematodes in existing landscape plants. Trees are susceptible to infection of witches' broom at vulnerable points, such as where there's been pruning or injury. These wounds can be caused by insects, irregular pruning, or damage that occurs naturally. Do not apply horticultural oil sprays when the temperature is above 90 F or to drought-stressed plants. glabra, zones 4-9) and winterberry (I. Check for mites by looking at the undersurface of leaves in early spring or by shaking a branch over white paper. Plant diverse species. Florida wax scale (Ceroplastes floridensis) on Chinese holly (Ilex cornuta).United States National Collection of Scale Insects Photographs Archive, USDA Agricultural Research Service, www.forestryimages.org. Remove and destroy (do not compost) all heavily spotted or fallen leaves. Holly tree berries: Small shiny black oblong fruits. JavaScript seems to be disabled in your browser. Then, spray the affected tree with locally recommended fungicides in fall or early spring. Plants with extensive root rot damage will usually decline and die during dry periods. If you have an infected holly, remove it from the soil to stop spread of the fungus to other plants. In addition, there are variegated holly shrubs with spiky leaves or leaves with smooth margins. Canker. Prevention & Treatment: Hollies grown under stress are much more sensitive to root rot disease than are well-maintained, vigorous plants. View our Privacy Policy here. The berries on holly trees are mildly toxic to humans. 3. Prevention is the best form of treatment and holly diseases can often be avoided by practicing sound garden management techniques. Care for plants well so that they are not under stress from other factors. Conferences. Perforated leaves of the holly that develop spine spot, as with other infected leaves, should be removed from the holly tree. See Table 1 for examples of products containing these active ingredients. A symptom of a fungal or bacterial condition or infection by several insects, gall is an odd and sometimes unsightly growth that can be found on a tree. Tar spot occurs when the airborne fungus Phacidium curtisii attacks the plant. Mites can be removed with a strong spray of water if applied on a regular basis. These spots turn reddish-brown and then black by the fall. Avoid excess nitrogen fertilizer in spring and early summer. The adult is about a -inch long and brown with two orangish-red stripes on the wings. Due to product cost and for accurate application, homeowners may want to hire a licensed landscaper to apply products containing these fungicides. Sometimes the spots even occur on berries. Grow as an evergreen screen to keep out unwanted intruders or wildlife. Damage: Infected leaves develop spots, turn yellow or brown and drop off the tree. If your holly is infected, yellow spots will appear on the leaves of American and English hollies in May. The yaupon holly tree is a multi-stemmed shrub-like holly tree with its dense foliage ideal for growing as a dense hedge. Mix thiophanate-methyl in water according to all label directions, and thoroughly saturate the ground around the plant with the mixture. Holly trees and bushes are large shrubs or trees, many of which have thick, glossy, spiky leaves, small white flowers, and yellow, orange, black, or red berries. Informational table showing disease name, symptoms, pathogen/cause, and management of Holly diseases. American holly (I. opaca) cultivars are particularly susceptible to leafminer damage. Remove and destroy (do not compost) all heavily spotted or fallen leaves. Although most species of hollies are evergreen plants, there are some deciduous holly bushes that drop their leaves in winter. The dwarf shrubs have all the recognizable features of the larger bushes and trees. The types of diseases that are harmful to holly trees include tar spot, cankers, purple blotch, spine spot and chlorosis. Using change detection technology, foresters can understand when woods are stressed. This article is a guide to the best types of holly trees and bushes for growing in your garden. Aileen Clarkson has been an award-winning editor and reporter for more than 20 years, earning three awards from the Society of Professional Journalists. The leaves of the holly appear yellow or pale green with deep green veins. Diseased stems and branches become swollen and enlarged, and an excessive number of shoots will sprout vertically from the infected areas. With all pesticides, read and follow all label instructions and precautions. Because of these factors, it's best to consult a tree care professional if you observe an outbreak of gall. Coniothyrium rarely causes serious damage, but the holly's leaves will turn yellow and drop early. Multiple infections, branch dieback, and disfigurement of tree crowns render trees unsightly and some are apparently killed by the disease. However, it is very important to always read and follow the label directions on each product. It is not safe to eat the red berries from a holly shrub or tree. The tree disease's growth is often a popular site for woodpecker feeding, as the bird is harvesting the beetles in the bark. cornuta, zones 7-9), American (I. How to Identify a Common Holly Tree Plant Disease - YouTube 0:00 / 1:45 How to Identify a Common Holly Tree Plant Disease TheWeekendgardener 7.49K subscribers 11K views 6 years ago. Tar Spot - Tar spot usually occurs with moist, cool springtime temperatures. Holly dieback due to Phytophthora root rot in a root cell. They feed on sap by piercing the leaf or stem with their mouthparts and sucking. Using sucking mouthparts, they feed on the undersides of leaves, where their fine webbing is often seen. Control: Naturally occurring predators of mites include various predatory mites, ladybird beetles, and other insects. Bag or burn the leaves to prevent the spread of disease. Neem oil extract or botanical oil sprays may also reduce plant damage by repelling many insect pests. Unlike common varieties of holly trees, the dahoon holly doesnt have spiky leaves. Cankers are also a fungal infection, affecting the stems of the leaves. Prune the tree to encourage better air circulation and mulch well to prevent the fungi from splashing up from the ground. The American holly ( Ilex opaca) is commonly used as a substitute for the English holly in Christmas dcor, in areas where the latter doesn't grow as well. Always try less toxic alternative sprays first for the control of insect pests and diseases. Black root rot can remain dormant in the soil for many years. Drench = Add to water and pour around base of plant. submitted to our "DoItYourself.com Community Forums". The identifying feature of the yaupon holly is its small, rounded leaves that dont have an apex. Keep trees healthy and prevent infection. Green, white, Autumn Purple, and the other ash trees are susceptible. With proper maintenance, your holly trees remain vigorous and more prepared to fight off or to resist fungal infections. Anthracnose usually infests English (Ilex aquifolium, USDA zones 7-9), Chinese (I. Please enter your email address below to create account. The larvae are about 1/16-inch long. Both varieties look similar, in that they have an abundance of red berries and sharp-toothed foliage. 1. This complicates the diagnostics, and the outcome is often lethal. You may freely link They attack sensitive and weakened trees and cannot be cured. Control: Shake infected leaves from the tree onto a disposable sheet or tarp and destroy them to prevent further infection. All rights reserved. Their usual size is 15 to 25 feet high and 8 to 10 feet wide. Adult beetle traps may lure more beetles than you already have in your garden. The small flowering evergreen tree grows well as a hedge or specimen plant in a garden landscape. Coniothyrium rarely causes serious damage, but the holly's leaves will turn yellow and drop early. Removing affected leaves will eliminate the spread of this disease. After mating, the female lays eggs in the bag, and then overwinters on a tree or shrub. More is not always better in gardening. Holly tree berries: Japanese holly tree berries are large, black, rounded fruits that look like large blackcurrants. Tar spot is a fungal disease caused by Phacidium curtisii. Remove diseased branches and limbs, pruning at least 12 inches into non-infected wood. The powdery material can be scraped off. Yellow spots appear on the leaves of American and English hollies in May. Holly tree berries: Yaupon holly tree berries are showy burgundy or red drupes that grow in large clusters.