Apple maggot (Order Diptera, Family Tephritidae) is not currently a pest of commercial orchards in Utah, but it is regulated as a quarantine insect in the state. If it becomes established in commercial fruit production areas, its presence can inflict sub
Codling Moth in Utah Orchards
Codling moth (Cydia pomonella; Order Lepidoptera, Family Tortricidae) is the most serious pest of apple and pear worldwide. In most of Utah, fruit must be protected season-long to harvest a quality crop. Insecticides are the main control tactic, with both
Eriophyid mites are translucent, cigar-shaped microscopic mites that cause deformities on many plants species. These mites are noticed when their feeding causes abnormalities of plant tissues such as erineum, galls, brooms, leaf curling, blisters, rusts,
European Red Mite
The European red mite is native to Europe and was first introduced into the Pacific Northwest in the early 1900s. Since then, it has spread and become established throughout the United States and Canada. Mites are tiny arthropods, measuring less than 1/60
The fall webworm is a common defoliator of ornamental and fruit trees in Utah. Starting around late July, the caterpillars, webbing, and damage become noticeable, particularly in some of the canyons adjacent to populated areas.
Gardening and Landscaping Practices for Nesting Native Bees
Utah is home to about 1,000 named species of native bees, with several hundred species living in any one valley and adjacent montane habitats. Urbanization takes its toll on native bees, but many species can persist with a little help from gardeners and
Important Pests of Ornamental Aspen
Aspens are one of the more popular forest trees in the Intermountain West. They add a brilliant yellow glow to the collage of fall colors. In an attempt to enjoy these beautiful trees around the home environment, many well-intentioned homeowners purchase
Pacific and Appletree Flatheaded Borers
Trees that are under stress or that have bark wounds are most susceptible to attack by Pacific flatheaded or flatheaded appletree borers Mature trees are not usually killed, but borer activity can weaken trees or contribute to eventual death. Newly plant
Peach Twig Borer
Peach twig borer (Anarsia lineatella) is found worldwide wherever stone fruits are grown. In Utah, it is a significant pest on peach/nectarine and apricot. There are typically three generations of peach twig borer in northern Utah (May-June, July, and A
The pear sawfly, which is actually a wasp, is a common pest on pear, cherry, and hawthorn in Utah. The slug-like appearance of the larval stage has prompted this insect to also be referred to as the pear or cherry slug in various parts of the country. Alt
Prionus Root Borer
Prionus root borers belong to a family of beetles commonly known as long-horned beetles. The larvae are often referred to as round-headed borers because their body shape is cylindrical. Several species in the Prionus genus are large, root-boring beetles,
Row covers on Utah farms. As an integrated pest management tool, row covers act as a physical barrier that prevents the movement of pests such as insects, birds, and mammals, to host plants.
Lily Leaf Beetle (Lilioceris lilii)
Lily leaf beetle (LLB) is an exotic pest from Eurasia that causes damage to plants in the Liliaceae family. Native and cultivated Lilium and Fritillaria are sensitive to attack, including rare and endangered species. LLB can cause economic and aesthetic l
Beginner's Guide to Common Native Bees
A beginner's guide to help identify common native bees in Utah, including social and solitary bees. The exotic western honey bee and bee "mimics" are also included, as well as information on human impacts on bees and what you can do to promote bee health.
Asian Giant Hornet
Asian giant hornet is an invasive wasp that was detected in northwest Washington and British Columbia, Canada in fall 2019 and spring 2020; however, it is not known to be established in those regions. It has not been detected in Utah.
European Cherry Fruit Fly
European Cherry Fruit Fly (ECFF) is a new invasive cherry-infesting pest that is not known to occur in Utah. Host plants include cherry and honeysuckle. Heavy infestations in Europe have resulted in 100% fruit loss. Since adults fly only short distances,
Imported Fire Ants
The red and black imported fire ants (IFA) are an invasive and aggressive pest not known to occur in Utah, but parts of southern Utah may be suitable for colony establishment. IFA can be easily distinguished from other ants in Utah by both the varying siz
The Samurai Wasp: New Hope in Fight Against BMSB
In June 2019, the samurai wasp [Trissolcus japonicus (Ashmead)] was discovered in Salt Lake City. This exotic parasitoid wasp is the most promising agent for biological control of BMSB and is uniquely evolved to lay its eggs inside of BMSB eggs. Help us p
The spotted lanternfly (SLF) is a new invasive pest from China that was first detected in the U.S. in Pennsylvania in 2014 and has since spread to other states. SLF attacks more than 100 host plants, including grapes, fruit trees, hops, and hardwood and o
Asparagus beetle and spotted asparagus beetle are leaf beetles in the family Chrysomelidae. These beetles feed exclusively on asparagus and are native to Europe. Asparagus beetle is the more economically injurious of the two species.
Codling Moth Mating Disruption
Mating disruption as a method to manage orchard pests became commercially available in the early 1990s, and was adopted by many Utah growers about a decade later. Use of this pest management technology c
Invasive Insects Lookalikes
Learn how to identify some invasive insects and their look-alikes. Here, we provide a quick identification guide for brown marmorated stink bug, Japanese beetle, emerald ash borer, and Asian longhorned beetle.
Sap beetles are typically considered a secondary pest of corn and overripe fruits and vegetables. Sap beetles are broadly identified by their small and ovular bodies and club-shaped antennae. Adult beetles feed on corn silk, pollen, and tassels. Larvae fe
General Concepts of Biological Control
“Balance of Nature.” Virtually all pest populations are affected by natural enemies to some extent. In many cases, natural enemies are the primary regulating force of the pest populations.
Using Degree Days to Time Treatments for Insect Pests
Degree days (often referred to as “growing degree days”) are accurate because insects have a predictable development pattern based on heat accumulation. Insects are exothermic (“cold-blooded”) and their body temperature and growth are affected by their su
Fruit Pests: Apple
A short summary of the main insect and disease pests of apples and how they are managed by the backyard fruit grower.
Fruit Pests: Apricot
A short summary of the main insect and disease pests of apricots and how they are managed by the backyard fruit grower.
Brown Marmorated Stink Bug
BMSB was first detected in Utah in 2012; it is now established in four counties (Weber, Davis, Salt Lake, and Utah) and has been detected in two other counties (Cache and Box Elder). As an aggressive generalist herbivore, BMSB infests a broad range of pla
The campylomma bug (or mullein plant bug; Hemiptera: Miridae) causes sporadic damage in Utah apple orchards. Damage is inflicted by nymphs, which feed on developing fruit causing dimpling and fruit distortion. As apple fruits mature, they become less susc
High Tunnel Management: Caterpillars
n Utah high tunnel production, there are a variety of caterpillar pests (larvae of moth and butterfly species) that cause economic damage to crops. Common caterpillar pest species found in Utah include hornworms, tomato fruit worms, imported cabbage worms
Fruit Pests: Cherry
A short summary of the main insect and disease pests of cherries and how they are managed by the backyard fruit grower.
Western Cherry Fruit Fly
The western cherry fruit fly (Rhagoletis indifferens, Order Diptera, Family Tephritidae) is the most important pest of sweet and tart cherries in Utah. Once the skin of fruits becomes soft enough to penetrate, adult females insert eggs with their oviposit
Damping-off is caused by several soilborne fungi including Pythium, Rhizoctonia, Fusarium and Phytophthora species. The fungi kill seedlings that are just germinating and seedlings that have been growing for several days.
Emerald Ash Borer
Emerald ash borer (EAB) (Coleoptera: Buprestidae) is an invasive woodboring beetle that has caused the decline and mortality of tens of millions of ash trees (Fraxinus spp.) in the U.S. It is considered the most destructive forest pest to ever invade Nort
Elm Seed Bug
First detected in 2014 in Utah, elm seed bug is now widely distributed along the Wasatch Front and Cache Valley, and has been reported west to Duchesne County, east to Tooele County, and south to Grand County. Elm seed bug activity peaks in mid-summer whe
Leafrollers in Fruit Orchards
Several species of leafrollers are economically important pests of tree fruits in North America. In Utah, injury to tart cherry crops from leafroller caterpillars prompted a 4-year survey for five species that are known to occur in the western U.S. Pherom
Tomato and Tobacco Hornworms
Tomato and tobacco hornworms are closely related species that cause similar damage to the same host plants. Both are equivalent in size and appearance. Tomato hornworms are the larval stage of the fivespotted hawkmoth (Manduca quinquemaculata) and tobacco
This fact sheet describes the invasive Japanese beetle (JB) and lists vegetative hosts that can be affected by JB, including ornamental plants, trees, shrubs, turfgrass and vegetables. This pest can cause significant damage in high numbers. It was first d
Western Conenose Bug (Kissing Bug)
Western conenose bug is an insect that feeds on the blood of vertebrates and can carry the parasite that causes Chagas disease of humans. This insect is present in Utah, but is not commonly found.
Fruit Pests: Peach & Nectarine
A short summary of the main insect and disease pests of peaches and nectarines along with how they are managed by the backyard fruit grower.
Fruit Pests: Pear
A short summary of the main insect and diseasae pests of pears and how they are managed by the backyard fruit grower.
Fruit Pests: Plum
A short summary of the main insect and disease pests of plum and how they are managed by the backyard fruit grower.
Powdery Mildew on Vegetables
Powdery mildew is widespread in Utah and affects many vegetables, fruit, and landscape plants. There are several species of powdery mildew fungi, and typically they target just a single host or only hosts in related plant families.
Small Hive Beetle
Small hive beetle (SHB) is a pest of honey and bumble bee colonies that is native to Africa. SHB feeds on pollen and honey, kills bee brood and workers, and causes honey to discolor and ferment.
Spotted Wing Drosophila
Spotted wing drosophila (SWD) is an invasive insect native to Southeast Asia; it was first detected in Utah in 2010. SWD management tactics include removing nearby alternative host plants, timely harvest of fruit, expanding the preventive insecticide prog
Spotted Wing Drosophila Monitoring
Spotted wing drosophila can attack fruit as soon as it begins to ripen, so that is when monitoring should begin. For example, place a trap in a cherry tree when the fruits begin to turn pink. Continue trapping for at least two weeks after harvest. Because
High Tunnel Management: Thrips
Thrips are a common pest that can be found on many high tunnel crops, plus hundreds of weed species. Two species commonly found in Utah include Western flower thrips and Onion thrips. Bean thrips may also occur in the state.
Velvet Longhorned Beetle
Velvet longhorned beetle is an invasive wood-boring beetle first detected in Utah in 2010. VLB can negatively impact fruit yield, tree longevity, and wood marketability. Prevention, monitoring, and early detection are the key management recommendations fo
High Tunnel Pest Management - Aphids
Aphids are small, pear-shaped insects with piercing-sucking mouthparts that feed on plant tissue. They can be found inside high tunnels all season long.