Education Commons^™

Ec98-1876 Foliar And Fruit Diseases Of Cucurbits, Jane A. Christensen, Loren J. Giesler

University of Nebraska-Lincoln Extension: Historical Materials

Members of the cucurbit family are well adapted to Nebraska's weather conditions and are grown in both gardens and commercial fields. Cucurbits include cucumbers, squash, melons, gourds, gherkin, vegetable marrow, and pumpkins. They are susceptible to varying degrees to diseases caused by fungi, bacteria and viruses. Accurate disease diagnosis is an essential part of crop management and can help growers attain maximum yields.

This extension circular explains these diseases of cucurbits and how to control them.

Ec98-151 Amaranth: Production Manual For The Central United States, Jane Sooby, David D. Baltensperger, Robert Myers, David Brenner, Richard Wilson, Charles Block

University of Nebraska-Lincoln Extension: Historical Materials

Amaranth is a small-seeded grain crop with a dramatic history. Once a staple in the diet of the Aztec Indians, today it is grown throughout the world. In the United States much of the production is small-scale and organic, grown mainly for the natural and health food markets. There also has been steady use of the crop for breakfast cereals, snack foods, and mass-produced multigrain bread products. Amaranth is a broadleaf plant well-adapted to a range of arid and humid environments. As a crop it fits into many dryland rotations, performing well following wheat, proso millet, or other grain crops. …

G97-1327 Cedar-Apple And Related Rusts Of Apple And Ornamentals, Don Steinegger, Jane A. Christensen

University of Nebraska-Lincoln Extension: Historical Materials

Discussion of complex inter-species disease life cycle in junipers and apple trees, description of symptoms, control measures, and lists of varieties of species resistant to cedar-apple rust and related rusts.

Cedar-apple rust is a disease that causes substantial injury to apple and crabapple trees in Nebraska. The disease is caused by the fungus Gymnosporangium juniperi-virginianae and occurs wherever apples and junipers are grown in close proximity.

G97-1326 Crabapples For Nebraska Landscapes, Don Steinegger, John E. Watkins

University of Nebraska-Lincoln Extension: Historical Materials

This NebGuide discusses the selection, care and disease possibilities of crabapples.

Many of the diminutive flowering trees are not hardy in Nebraska. One notable exception: the ornamental crabapple tree (Malus). By carefully selecting the planting site and the cultivar, the beauty of flowering crabs can be enjoyed in any part of the state.

Regardless of the season, crabapples lend landscape color and interest. The winter branch pattern and bark color are as much an asset as spring's flower color.

G97-1321 Powdery Mildew Of Landscape Ornamentals, John E. Watkins

University of Nebraska-Lincoln Extension: Historical Materials

Powdery mildew can diminish the beauty of landscape ornamentals; however, it can be controlled through cultural practices or chemical alternatives.

Powdery mildew is the name for the grayish white powdery coating of fungus mycelium and masses of spores growing on plant leaves, shoots and flowers. This disease is caused by a distinct group of similar fungi that attacks a wide variety of plants. Lilac, zinnia and many other flowers and shrubs can be damaged. Although plants infected with powdery mildew rarely die, the disease detracts from the natural beauty of ornamentals. Damage ranges from an unsightly white powdery coating on …

G96-1289 Diseases Of Home Garden Strawberries, John E. Watkins, David S. Wysong

University of Nebraska-Lincoln Extension: Historical Materials

This NebGuide addresses on some of the common diseases affecting home garden strawberries in Nebraska and their control.

Strawberries are a favored fruit of home gardens. They have been adapted to a wide range of environmental conditions, but sometimes can be challenging to grow. Strawberry yields and fruit quality are influenced by interactions of environment, diseases, pests, and soil conditions.

Nf95-213 1995 Home Garden And Landscape Fungicide Survey, John E. Watkins, John C. Fech

University of Nebraska-Lincoln Extension: Historical Materials

This NebFact has information on the various fungicides available and what types of plants they are registered for.

Ec95-1873 Cultural Practices That Influence Wheat Diseases, John E. Watkins, Robert N. Klein, Paul C. Hay, Lenis Alton Nelson

University of Nebraska-Lincoln Extension: Historical Materials

The health of a wheatcrop is determined well before the crop is planted. It is often the result of subtle factors in the management history of the field, including varieties, seed quality, seedbed, planting date, residue management and post harvest weed control. Wheat health management practices before the crop is planted must limit, as much as possible, the number of production hazards that must be dealt with after planting. Important diseases influenced by cultural practices include crown and root rot, wheat streak mosaic, soil-borne wheat mosaic, barley yellow dwarf, leaf rust, smut diseases, scab, Cephalosporium stripe and tan spot.

G95-1250 Rust Of Dry Bean, James R. Steadman, H. F. Schwartz, Dale T. Lindgren

University of Nebraska-Lincoln Extension: Historical Materials

The symptoms, sources, spread and management of rust in dry edible beans is discussed in this NebGuide.

Rust is an important disease that affects dry beans in eastern Colorado, western Nebraska and adjacent regions. The disease is caused by the fungus Uromyces appendiculatus which has caused periodic epidemics in this region since the 1950s. Recent yield losses from the disease have exceeded 50 percent in some areas.

Ec95-1250 Forecasting Late Blight, Alexander D. Pavlista, Walter R. Stevenson

University of Nebraska-Lincoln Extension: Historical Materials

A method for forecasting environmental conditions favorable to the development of late blight is described. How is weather data obtained from hygrothermographs and weather stations? How are the data used to calculate severity values? How is late blight forecasted and fungicide applications scheduling recommended? These questions will be answered here. The intended audience is potato growers; tomato growers would also benefit.

G95-1270 Sclerotinia Stem Rot Of Soybeans, James R. Steadman, S. Rutledge, D. Merrell, David Wysong

University of Nebraska-Lincoln Extension: Historical Materials

Life cycle, symptoms, and control measures of sclerotinia stem rot of soybeans is discussed.

Sclerotinia stem rot of soybeans is caused by the fungus Sclerotinia sclerotiorum. This pathogen has an extremely wide host range and can affect more than 400 plant species, including oilseed, vegetable and forage legume crops. S. sclerotiorum has caused a disease known as white mold on dry edible beans in western Nebraska for 40 years, but it did not become a problem in soybeans until the 1990s. This fungal pathogen can be found on soybeans in Illinois, Iowa, Michigan, Ohio, Minnesota, Wisconsin, and North Dakota. …

Ec94-138 Pigweed Identification: A Pictorial Guide To The Common Pigweeds Of The Great Plains, M.J. Horak, D.E. Peterson, D.J. Chessman, L.M. Wax

University of Nebraska-Lincoln Extension: Historical Materials

Several pigweed species are found in the Great Plains. Pigweeds commonly reduce crop yields and interfere with harvest. One means of controlling these weeds is through the use of herbicides. Recent research indicates that some pigweed species respond differently to various herbicides; therefore, proper identification is needed for good control.

This extension contains a generalized distribution map; photographs of seeds, seedling, and mature plants; and text describing other identifying features for each pigweed species. The species are grouped with others that have similar shape and form. The pigweed species listed in this publication are: redroot pigweed, smooth pigweed, Powell amaranth, …

Ec94-132 Freeze Injury To Nebraska Wheat, Robert N. Klein, Drew J. Lyon, John E. Watkins

University of Nebraska-Lincoln Extension: Historical Materials

Nebraska’s adverse weather conditions affect winter wheat during much of its growth. The newer varieties of wheat have increased winter hardiness, and better management practices have reduced winter injury of winter wheat, yet low temperature injury during winter and spring can be destructive. Wheat has little resistance to low temperatures after it begins growing in the spring; therefore, injury from freezes at this time can occur in any part of the state. This publication describes temperature conditions that cause winter injury, symptoms of injury at different spring growth stages, and management practices to use when wheat is injured.

G94-1207 Scab Of Wheat, John E. Watkins, Ben Doupnik, Jr.

University of Nebraska-Lincoln Extension: Historical Materials

The identification of and disease cycle of wheat scab is described along with its management. Guidelines for using wheat contaminated with vomitoxin also are included.

Scab or Fusarium head blight is an important disease of wheat, barley, oats, rye and wheatgrasses. Scab manifests itself by the premature death or blighting of spikelets in the wheat head. Direct yield losses are often minor, but can be higher than 50 percent in severely infected fields. The economic significance is magnified by the possibility that the low quality, shriveled grain also can become contaminated by mycotoxins (e.g. vomitoxin, zearalenone).

G94-1200 Anthracnose Diseases Of Shade Trees (Revised July 1997), Laurie J. Stepanek, Mark O. Harrell, David S. Wysong

University of Nebraska-Lincoln Extension: Historical Materials

This NebGuide describes anthracnose diseases in sycamore, ash, oak, maple and walnut trees and offers suggestions for control.

Anthracnose diseases affect a wide variety of plants including many popular shade trees. Sycamore, ash, oak, maple, and walnut commonly exhibit symptoms each spring. Although the symptoms may appear serious, anthracnose diseases rarely kill trees. In most cases, healthy trees quickly recover from anthracnose infections with little damage to their long-term health.

G93-1149 Stripe Smut Disease Of Turfgrass, John E. Watkins, Roch E. Gaussoin

University of Nebraska-Lincoln Extension: Historical Materials

Ways to identify and treat smut fungi are given here.

Smut fungi infect various grasses, either cultivated or found naturally in the wild. In turfgrass, one of the most common smut diseases is stripe smut caused by Ustilago striiformis.

Stripe smut occurs most commonly on Kentucky bluegrass, occasionally on bentgrass and rarely on fine fescues and perennial ryegrass; it has not been reported to occur on zoysia. The widespread use of susceptible Kentucky bluegrass cultivars has contributed to the common occurrence of stripe smut.

Stripe smut should not be taken lightly by turfgrass managers. Infection causes a general decline, …

G92-1119 Rust Diseases Of Turfgrass, John E. Watkins, Roch E. Gaussoin

University of Nebraska-Lincoln Extension: Historical Materials

This NebGuide describes the various rust diseases common to Nebraska and offers suggestions for maintaining a vigorous and disease-resistant lawn.

Rust diseases occur on all turfgrasses; however, most rust problems occur on Kentucky bluegrass, perennial ryegrass, tall fescue and zoysia. In the cool-temperate regions of North America, cool season turfgrasses may suffer severe injury late in summer by attack from one of the rust pathogens. In addition, rust-weakened plants are much more susceptible to injury from environmental stresses and to attack by other turfgrass pathogens.

G92-1100 Sugar Beet Nematode, Eric D. Kerr, F.A. Gray, G.D. Franc

University of Nebraska-Lincoln Extension: Historical Materials

Symptoms, life cycle and control of sugar beet nematodes are among the topics covered here.

The sugar beet nematode, schachtii, is a major parasite of sugar beets, causing serious stand and yield reductions. It was first identified in 1859 on sugar beets near Halle, Germany. It was first observed in the United States as early as 1895 and was reported in two fields near Gering, Nebraska in 1926.

G92-1103 White Mold Of Dry Beans, James R. Steadman, Howard F. Schwartz, Eric D. Kerr

University of Nebraska-Lincoln Extension: Historical Materials

White mold symptoms, infection and control are covered here.

One of the most important diseases affecting dry beans in western Nebraska and Colorado is white mold caused by the fungus Sclerotinia sclerotiorum. In a recent year, losses from this disease averaged as high as 20 percent, with a few individual field losses exceeding 65 percent.

G92-1120 Fire Blight Of Apple, Pear And Woody Ornamentals, John E. Watkins

University of Nebraska-Lincoln Extension: Historical Materials

This NebGuide tells how fire blight is spread among apple, pear and woody ornamentals. It describes the disease cycle and offers advice for treatment and protection.

Fire blight, caused by Erwinia amylovora, is the oldest, most serious bacterial disease of apple and pear. It was first reported in the late 18th century in the Hudson River Valley in New York. The disease is indigenous to North America, and probably occurred on native American plants such as crabapple, hawthorn and mountain ash and then spread to susceptible cultivated apples, pears and woody ornamentals planted by the early American pioneers. As …

G92-1090 Black Dot Disease Of Potato, Alexander D. Pavlista, Eric D. Kerr, Robert B. O'Keefe

University of Nebraska-Lincoln Extension: Historical Materials

The cause, symptom, disease cycle, influencing factors, effects and control of black dot are described. Black dot of potato, a disease caused by the fungus Colletotrichum coccodes, was recognized in Australia and Europe, then was observed and described in Canada in 1921. Since then this disease has spread to many potato production areas of the United States; its occurrence was first reported in Nebraska in 1988. In the past few years, black dot has been recognized on infected potato tissue from several areas of the state. The increased incidence of black dot in Nebraska may have been favored by high …

G91-1022 Guide To Growing Houseplants, Don Steinegger, Frederick P. Baxendale, John E. Watkins

University of Nebraska-Lincoln Extension: Historical Materials

Proper care can extend houseplants' lives. This NebGuide offers hints on conditioning, light, fertilizing and more.

Many people enjoy houseplants; in fact, raising them is one of the fastest growing indoor hobbies. Caring for houseplants offers opportunities for people who like to work with living things and watch them develop. Today, houseplants are an integral part of indoor decor -- especially in winter.

An artificial indoor environment often hinders plant development. High temperatures, low humidity, lack of sunlight, poor soil conditions, and improper watering contribute to most houseplant problems. In addition, insects or plant diseases occasionally damage houseplants.

While plants …

G91-1060 Black Spot Of Roses, John E. Watkins

University of Nebraska-Lincoln Extension: Historical Materials

Black spot, Nebraska's most troublesome rose disease, can be controlled through selection of a resistant cultivar, spaced plantings, and an active fungicide spray program.

Roses are one of the most versatile and inspiring ornamentals for landscaping. There are roses adapted for any garden site and landscape purpose. Roses are not always easy to grow and may require a little more management than other ornamentals. One of the greatest challenges to successfully growing garden roses is disease control.

G91-1016 Cool Season Turfgrass For Nebraska, Terrance P. Riordan, Garald L. Horse

University of Nebraska-Lincoln Extension: Historical Materials

This NebGuide describes 12 species of cool season turfgrasses and the recommended cultivars which are best adapted to Nebraska.

Cool season turfgrasses have an optimum soil temperature of 60-70°F. They grow most actively in the spring and fall, with growth slowing in summer. More than 20 cool season species are used for turf throughout the world.

Nebraska's climate is moderately conducive to cool season turfgrass species growth. The 12 species best adapted to Nebraska and some of the recommended cultivars are described.

G90-970 Summer Patch And Necrotic Ring Spot, John E. Watkins, Robert C. Shearman, Terrance P. Riordan

University of Nebraska-Lincoln Extension: Historical Materials

This NebGuide describes the causes, predisposing conditions, and symptoms of summer patch and necrotic ring spot, and provides recommendations for their control.

Research since 1980 has resulted in considerable progress in identifying causes of the "patch"-type disease of turfgrass. Two of the most destructive patch diseases of turfgrasses are summer patch and necrotic ring spot.

Both summer patch and necrotic ring spot are present in Nebraska turfs. Unfortunately, necrotic ring spot and summer patch cause identical symptoms and cannot be distinguished in the field, and identification in the laboratory is time-consuming (3-6 months) and laborious.

G90-980 Rose Mosaic And Rose Rosette Diseases, John E. Watkins

University of Nebraska-Lincoln Extension: Historical Materials

The rose mosaic and rose rosette diseases may cause a variety of symptoms, including reduced plant vigor and flower quality. Early detection is essential to control.

Roses have been cultivated as an ornamental for 4,000 to 5,000 years and now are distributed worldwide. Rose virus and virus-like diseases occur wherever roses are grown. Since roses are vegetatively-propagated through budding or grafting, these pathogenic agents are easily spread during propagation. Infection by virus or virus-like agents may cause a wide variety of symptoms. These can range from latent, symptomless infections to mosaic leaf patterns and distortions, severely distorted canes, and finally, …

G90-979 Powdery Mildew Of Roses, John E. Watkins

University of Nebraska-Lincoln Extension: Historical Materials

Cause, symptoms of and conditions for powdery mildew are covered, as well as ways to control the disease.

The rose is one of the most popular flowering ornamentals in the world. It is thought to have first been cultivated 4,000 to 5,000 years ago in northern Africa. Today it is a favorite ornamental for landscapes, as well as the most important commercial cut flower.

G89-925 'Helminthosporium' Leaf Spot And Melting Out Diseases Of Turfgrass (Revised December 1995), John E. Watkins, Roch E. Gaussoin, Terrance P. Riordan

University of Nebraska-Lincoln Extension: Historical Materials

Symptoms and controls for "Helminthosporium" leaf spot and melting out are discussed.

Leaf spot and melting out are two fungal diseases of turfgrass within the "Helminthosporium" leaf, crown and root disease complex. They are the most common and serious groups of cool season turfgrass diseases in North America.

G89-951 Mushrooms, Puffballs, Fairy Rings, And Slime Molds In Turfgrass, John E. Watkins

University of Nebraska-Lincoln Extension: Historical Materials

How do you identify -- and treat -- mushrooms, puffballs, fairy rings and slime molds? Read on.

Some mushrooms and most puffballs are edible; some are foul-smelling, many are considered unsightly, and a few are poisonous; but when they appear on a lawn, most are considered a nuisance.

G89-900 Phytophthora Root Rot Of Alfalfa, John E. Watkins, Fred A. Gray, Bruce Anderson

University of Nebraska-Lincoln Extension: Historical Materials

Disease cycle, symptoms and management practices for phytophthora root rot are discussed in this NebGuide.

Phytophthora root rot (PRR) is a major cause of seedling death in newly established alfalfa, and causes a progressive decline of established stands in Nebraska. This disease is caused by the fungus Phytophthora megasperma f. sp. medicaginis and occurs in most of the alfalfa producing areas in North America.

The Phytophthora that infects alfalfa is different from the Phytophthora that causes root rot in soybeans. Growers sometimes think the two diseases are the same for the respective crops, but they are two different diseases with …