Program Management

BACTERIAL & VIRAL DISEASES There are two common bacterial diseases that occur in landscapes in Los Angeles County: fire blight and diseases caused by the bacteria Xylella fastidiosa which include bacterial leaf scorch and Pierce’s Disease. Fire Blight Fire blight is caused by the bacterium Erwinia amylovora. It is common on apple, pear, crabapple, [...]

Fungal Diseases The most common fungal diseases in Los Angeles County are powdery mildew downey mildew rust anthracnose leaf spots phytophthora root rot armillaria root rot Refer to the following for general information on each. Powdery Mildew Powdery mildew is common on many landscape plants and can be expected to occur whenever a susceptible [...]

Managing Weeds in Turf Prevention Site preparation The healthy lawn starts with a properly prepared site before planting. All of the methods discussed in the landscape section apply to the establishment of a new turf area as well including amending the soil with organic matter or nutrients to improve seed plant establishment and improvement [...]

MANAGING WATER How water is managed can have has a significant effect on plant health as well as pest infestations. This Section contains a comprehensive guide to proper plant watering including how much, how often and how different soil types may effect plant watering. While it may be possible to maintain plants with a [...]

INTRODUCTION TO PLANT DISEASES Landscape plants suffer from a wide variety of plant diseases and disorders. Plant disease can be separated into biotic diseases and abiotic disorders. Biotic diseases are caused by living microorganisms such as fungi, bacteria, viruses, or phytoplasmas. Abiotic disorders are caused by environmental factors such as frost, saline soil, extreme [...]

Managing Weeds in and Around Landscaping Preventing Weeds Prior to Planting Landscaping When putting in new landscaping, or when renovating an existing site, following the steps outlined below may help prevent weed some problems: Site Assessment: Before planting the site and while it is in its “natural” state, it should be evaluated as to [...]

An ACWM (formerly Horticultural Department) employee examines the newly arrived invasive weed, puncturevine, in 1929. MANAGEMENT OF WEEDS Management of weeds in Los Angeles County can range from techniques as modest as a few swipes each week with a scuffle hoe in landscaping, to large scale herbicide applications requiring integration of complex [...]

Aphids, Mealybugs, Whiteflies and Scale Insects There are several species of aphids, mealybugs, whiteflies, soft and armored scale insects that become pests of landscape plants where they may be commonly found sucking juices on various parts of the plant. The majority of the species prefer young shoots and leaves. Most plants can sustain moderate [...]

INVERTEBRATES The term Invertebrate refers to animals without backbones such as insects, spiders, worms, and snails. This section contains information on many of Los Angeles County’s most common invertebrate pests that injure landscape plants. An internet search using any of the scientific names provided will reveal a wealth of additional information including images. Can’t [...]