Michigan’s climate is generally more humid, especially in the summer, which is ideal for fungal pathogens to thrive. As a result, trees affected by needlecasts often have an outer “shell” of live needles on current shoots and dead needles on older shoots (Photo 3). program! The classic symptoms of needle cast include brownish purple discoloration and eventual death of older needles, while current-year needles show no symptoms (Figure 1). Trees are most likely to be infected if they are planted too closely together or if they are stressed, Yiesla said. Spruce spider mites. Some of these conifer dieback symptoms appear in well-established trees. Covering large parts of Europe, Norway spruce (Picea abies L Karst.) Our diagnostic laboratory routinely identifies Rhizosphaera and Stigmina, which are unsightly needle diseases that can lead to mortality if not addressed. Tip blights. For more information, visit https://extension.msu.edu. Both diseases also can occur simultaneously and progressively speed up the decline of this popular tree. Over the past few years, many homeowners have been alarmed by what seems to be a sudden decline of their blue spruce trees. Left, Needlecasts kill older (inner) needles, but leave newer needles unaffected. However, a recent survey by Michigan State University researchers suggests two other fungal pathogens, Diplodia and Phomopsis, were much more commonly associated with branch death and tree decline than Cytospora (Photos 8-9). plays an important role in the adaptation strategy of forest services to future climate change. In recent years, most all spruce varieties have been having difficulty fighting off the fungal disease Rhizosphaera needle cast. AdstockRF; Major species. June 28, 2019. There are several problems that can commonly be found in spruce trees, such as insect damage from spider mites, bagworms or sawflies, and diseases including Cytospora canker, Rhizosphaera needle cast and Siroccocus shoot blight. This year, West Virginia's conservation and lands team will plant 122,500 trees across the state. This fungal disease causes premature death and … Spruce trees are not able to form new needles where the old ones dropped. Trees may produce ridges of wound tissue around older canker infections as the tree attempts to restrict the fungus’ growth. As a result, they are stressed and more susceptible to fungal pathogens. 'Skylands' should be protected from hot afternoon sun on summer's longest days or it will burn. This red spruce story goes back to the 1960s. There are a number of factors contributing to the decline we see in blue spruce trees, including environmental changes, poor site conditions and new pathogens. Over the past decade, spruce trees have suffered an abundance of issues. If you can pin down a specific reason for the tree's decline, treat that reason directly. Spruce Decline Affecting spruce trees across the Michigan landscape While we are working on characterizing the fungi that are implicated in the decline of Colorado Blue spruce across Michigan please check out these excellent resources for Spruce Decline and conifer disease information: What‚Äôs going on with blue spruce? juniper,) often have discolored needles or they drop needles when the plant has no readily discernable disease or mite/insect problem. To identify the fungus look closely at the infected needles. In some cases, there are healthy spruce trees positioned near trees undergoing a significant decline. Description. Middle, New shoot tips killed by Phomopsis tip blight. 2. • Current needles near galls may be green; needles are dead and discolored on older shoots with galls. Overview. Colorado blue spruce trees have long been among the most popular conifers for landscaping in Michigan and the upper Midwest. Colorado blue spruce is native to arid regions in the Rocky Mountains. The rapid decline of many spruce trees in Michigan and surrounding states appears to be related to an increase of canker diseases coupled with other disease and insect problems that plague the species. Asked June 20, 2020, 7:56 AM EDT. Colorado blue spruce trees, although not native or adapted to Maryland, are commonly planted in landscapes for their attractive color and shape. View bios on each of our bloggers, or click on a name to go to that blogger’s profile page. Right, Wood staining on branch with Phomopsis canker. All species of spruce, including Colorado blue and white spruce, are being affected, but particularly concerning is the prevalence of ‘decline’ symptoms on well-established Norway spruce. In landscapes, Colorado blue spruces have been planted on some sites that are marginal for their success. Two needle cast diseases occur in North Dakota: Rhizosphaera needle cast and Stigmina needle cast. Symptoms of both needle cast diseases look similar to each other. For canker diseases, the effectiveness of fungicides is usually limited. Reference to commercial products or trade names does not imply endorsement by MSU Extension or bias against those not mentioned. • Generally an aesthetic problem, especially on larger trees. There are a number of factors contributing to the decline we see in blue spruce trees, including environmental changes, poor site conditions and new pathogens. As the name implies, trees with needlecast diseases shed needles. Photos 8-9. Kimberly Bohn, Ph.D. Former Extension Educator, Forestry and … Right, Resin oozing from a branch canker caused by Cytospora. Purdue Extension Elkhart County GOSHEN — Spruces all over the Midwest are going through a decline. Needlecasts. The key symptom of spruce decline is branch dieback, which progresses over two to four years and renders the plant’s appearance unacceptable for most homeowners (Photo 2). If you wish to save the tree, I would advise pruning out the affected … Cytospora canker is a disease of mature spruce trees, usually older than 15 years. Gall adelgids. There are three principle types of diseases that affect blue spruce trees: needlecasts, tip blights and canker diseases. Oystershell Scale: An Unusual Insect Pest. Finally, for decades the default diagnosis for most problems with blue spruce has been Rhizosphaera needlecast or Cytospora branch canker. Correct identification, often with microscopic observation, is important to identify the issue correctly. Photo credits: Left and middle photo, Dennis Fulbright, MSU; right photo, Michael Kangas, NDSU, Bugwood.org. Throughout the Midwest, Colorado blue spruces have been showing needle loss, dead branches, and browning foliage. Canker diseases are most commonly found on trees under stress so landscape trees should be monitored closely. Michigan State University Extension programs and materials are open to all without regard to race, color, national origin, gender, gender identity, religion, age, height, weight, disability, political beliefs, sexual orientation, marital status, family status or veteran status. Key site factors for blue spruce trees are full sunlight, good air movement and excellent soil drainage. You might’ve noticed there’s something strange going on with the spruce trees in your neighborhood. Population levels oscillate, sometimes reaching extreme outbreak levels that can cause extreme defoliation of and damage to spruce trees. Browning and loss of innermost needles on the lower branches is often the first visible symptom of Rhizosphaera. The symptoms of spruce decline are progressing branch dieback which starts on the inner needles and works its way out over several years. MSU is an affirmative-action, equal-opportunity employer. Blue spruce is very susceptible, as are black, Engelmann, red, Sitka, and white spruces. Dwarf varieties and properly spaced larger spruce varieties will have better air penetration and needles will dry more quickly. Symptoms of forest decline of spruce in Europe range from needle yellowing and loss to tree and stand mortality. Bartlett’s Tree Topics blog follows in that tradition by offering a place to receive advice on trees, tree pests, tree preservation, and more. White pine weevil attacks leader shoots in Norway spruce causing them to bend like a shepherd's hook and the needles to fall off. • Cooley spruce galls are mainly on Colorado blue spruce and white spruce. Originally a favorite due to the relatively low incidence of health issues, the Norway spruce is now experiencing serious health concerns. Often times, people are more likely to see the damage as opposed to the insect pests themselves. It’s called spruce decline and it’s mostly affecting Colorado blue spruce.. Michigan’s climate is generally more humid, especially in the summer, which is ideal for fungal pathogens to thrive. In both cases, the insect pests are tiny and you may need a hand lens to see them. Spruce trees and other conifers (including pine, arborvitae, and . Norway spruce are now experiencing serious health concerns. As a result, bare areas develop on the tree, reducing its ornamental value and overall health. Save For Later. Photo credits: Left photo, Christine McTavish, MSU; right photo, Dennis Fulbright, MSU. Right, Needle damage caused by mites. If 'Skylands' gets too big for your garden, there is a select "Skylands seedling" called 'Firefly' that displays the same golden foliage, but grows more slowly and stays smaller. Weather-related stresses and other biotic/abiotic factors involving the root collar, root system, soil nutrient, pH, compaction, and drainage need to be evaluated to help keep spruce trees healthy. Needlecast fungi often infect needles on the current year’s shoots. The two most common needlecasts we find in spruce are caused by the fungal pathogens Rhizosphaera and Stigmina/Mycosphaerella. 1. Not sure if spider mites or not. There are, however, two plant diseases that commonly infect and disfigure them. Michigan’s climate is generally more humid, especially in the summer, which is ideal for fungal pathogens to thrive. To have a digest of information delivered straight to your email inbox, visit https://extension.msu.edu/newsletters. Although dendroecology can provide valuable information on the past relationships between tree growth and climate, most previous studie … The first sign of trouble is the browning of needles on the lower branches, which gradually spreads upwards. Being a leader in the tree care industry means continually focusing on learning and innovation. Spruce decline is pretty much what it sounds like – the lower branches on the tree start turning brown and dying. Unfortunately, blue spruce trees are subject to a wide range of insect and disease problems that can impact their growth and aesthetic appeal. Videos Length: 00:07:09. Also consistently seen are Phomopsis and Cytospora, serious and deadly canker diseases on stems. This information is for educational purposes only. I held a white paper underneath and hit branch. Adelgids are small insects that feed on shoots by sucking plant sap. This distinction is important since not all insecticides will control mites. Check out the Agribusiness Management B.S. Jeffrey W. Dwyer, Director, MSU Extension, East Lansing, MI 48824. The 4-H Name and Emblem have special protections from Congress, protected by code 18 USC 707. This article was published by Michigan State University Extension. All species of spruce, including Colorado blue and white spruce, are being affected, but particularly concerning is the prevalence of ‘decline’ symptoms on well-established Norway spruce. Colorado blue spruce is native to arid regions in the Rocky Mountains. To contact an expert in your area, visit https://extension.msu.edu/experts, or call 888-MSUE4MI (888-678-3464). Home to 240 rare plant and animal species, red spruce forests once covered the rocky peaks of West Virginia’s high country but were decimated by logging in the late 1800s and early 1900s. Over the past decade, spruce trees have suffered an abundance of issues. Proper mulching, watering and soil care are the best ways to prevent infection. Two of the main host plants are black spruce and white spruce. There are, however, two plant diseases that commonly infect and disfigure them. For control to be fully successful, it may take two to three years of yearly fungicide applications. Bert Cregg, Christine McTavish, Andrew Jarosz, Jill O'Donnell, and Dennis Fulbright Michigan State University - There are a number of factors contributing to the decline we see in blue spruce trees, including environmental changes, poor site conditions and new pathogens. Issued in furtherance of MSU Extension work, acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture. Also check existing spruce trees for the disease. Photo credits: Jill O’Donnell, MSU. Frequently asked questions about spruce decline. Rhizosphaera needlecast Dry needles are less likely to be infected. Tip blights are fungal diseases that typically cause dieback to new, emerging shoots (Photo 4). Blue spruce trees are widely planted due to their good growth rate, stately form and, of course, their blue foliage. Diagnose the problem. Although spruce decline is widespread and appears to be increasing, it is not a certainty that all trees will be affected. ), which turn needles red or lavender, respectively, and can leave large areas in the tree bare after needles are shed. As with any tree health problem, the first step in dealing with declining spruce trees is to diagnose the problem and identify the cause. Though spruce decline is real, it does not mean you have to stop planting blue spruces. Tip blights are most common on pines, especially Austrian pines, but can also occur on spruces. Another complicating factor is that trees may be healthy for a number of years and then begin to decline as they mature and are more difficult and costly to remove. If you can't, give the tree an all-around treatment. Alternative conifers for Michigan landscapes. For large or important landscape trees, homeowners should contact a professional arborist or tree care company. Why Spruce Trees Lose Their Needles, Purdue Extension Blue Spruce Decline, Purdue Extension Diseases Common in Blue Spruce, Purdue Extension Tree Installation: Process and Practices, The Education Store, Purdue Extension resource center Tree Planting and Urban Forestry Videos, Subscribe to our Purdue Extension-FNR YouTube Channel I have 3 spruce trees in landscape near each other. Photos 6-7. Find them at the tips of new growth. It is important to note that fungicide treatments for needlecasts only protect new growth. Spruce trees are the most problematic of all conifers in our landscape right now. Canker diseases are caused by fungi that infect branches or the main stem of trees. New pathogens seem to be discovered annually, and the unusual weather conditions in recent years have further complicated everything. Another key characteristic of needl… 2. Branches may begin to die after 3-4 years of early needle loss. Each pest causes specific damage or symptoms on trees, such as yellow pin pricks on needles affected by spider mites and black fungal structures on needles killed by Rhizosphaera needle cast. Spruce spider mites cause needle discoloration and eventually kill needles, which can be mistaken for a needlecast disease (Photo 7). Some little bugs fell out. The youngest needles at the tips of branches typically remain healthy. Other reports of dieback are on trees … For some disease issues, such as needlecasts, fungicides may be effective in preventing or controlling the disease. 3. As “Beatlemania” was invading the rest of the country, Hub Vogelmann, professor of botany at the University of Vermont and iconic conservationist, and graduate student Thomas Siccama were doing routine plant surveys on Camel’s Hump in the Green Mountains of Vermont. Black spruce (Picea mariana) and white spruce (P. glauca) are found throughout most of northern North America, from the Great Lakes to the Arctic tree line. The likelihood of having success can be improved by planting blue spruce trees on sites with conditions they favor. MSU is an affirmative-action, equal-opportunity employer, committed to achieving excellence through a diverse workforce and inclusive culture that encourages all people to reach their full potential. Colorado blue spruce trees, although not native or adapted to Maryland, are commonly planted in landscapes for their attractive color and shape. As there are multiple cankers on the tree, the odds of this tree thriving are not good. In fact, it is not uncommon to see healthy, thriving spruce trees near or adjacent to trees that are in severe decline. Similarities and differences between the two diseases exist. The rapid decline of many spruce trees in the Midwest appears to be related to an increase of canker diseases coupled with other disease and insect problems that plague the species. Canker diseases. The bottom line is not all spruce trees will be impacted. Technically, mites are not insects, but are related to spiders. This is a difficult question. There is not a whole lot we can do about it. Colorado blue spruce is native to arid regions in the Rocky Mountains. As they do so, they cause the shoots to deform and produce galls that resemble cones (Photo 6). Both diseases also can occur simultaneously and progressively speed up the decline of this popular tree. The leading company in tree care service since 1907. All of these diseases are caused by fungal pathogens and each produce specific symptoms that can be useful in diagnosing the problem. Another fungal disease that causes loss of needles is Stigmina, which is often mistaken for Rhizosphaera. ... 2/3 of the tree is in moderate to severe decline. They prefer acid soils, that are coarse textured with good drainage, have adequate water and sheltered from extreme weather conditions. Picea orientalis 'Skylands' is another oriental spruce tree; its distinctive feature is its lovely golden foliage. Instructors. Typical symptoms of cankers are sunken areas along a stem that may ooze resin (Photo 5). The prevalence of diseases on blue spruce trees has intensified in recent years and trees are declining rapidly in many areas (Photo 1). Also, in many cases there may be more than one issue that is affecting your tree’s health. Removing affected branches is usually the best action to improve the tree’s appearance and slow the spread of disease within the tree. As cankers develop, they can interfere with the branch’s ability to transport water and nutrients, resulting in the death of individual branches often referred to as “flagging.”. Spruce is a common grown shelterbelt tree in Manitoba. Asked August 1, 2016, 2:48 PM EDT. Environmental factors such as drought stress, elevated summer temperatures, and wetter growing seasons have played a significant role in twig dieback and needle defoliation. • Eastern spruce galls mainly affect Norway and white spruce. Height usually 40' to 60', occasionally 100', with a diameter of 24"; straight trunk; long, stout branches form broad conical head. If conditions are not ideal, the trees will begin to decline and become more susceptible to pests. One is turning a lighter more yellow color and others are nice and green. Spruce trees have shallow root systems and become stressed during drought, making them vulnerable to insect damage. Spruce decline. Michigan State University Extension recommends homeowners diversify their landscapes to help make their landscapes more resilient to pest and environmental changes, and seek to plant a variety of species wherever possible. There are so many factors contributing to their decline that it has become nearly impossible to tease them apart. Diplodia and Phomopsis are both considered weak or secondary pathogens, so it is unclear at this point why they appear to cause major disease problems for spruce. Left, Decline symptoms moving upward. In severe cases, the disease can kill entire trees. Unfortunately, when most people call, the damage is so severe it is past the treatment stage, or As the disease progresses, the needles die, usually the year following the infection. While beautiful in shape, color and texture, spruces are not native to our region, and that plays a role in their demise. The eastern spruce budworm (Choristoneura fumiferana) is a major pest of spruce trees in forests throughout Canada and the eastern United States. Photos 3-5. It is most common on trees less than 20 feet tall, and is fatal to trees less than 4 feet tall. Left, Gall caused by Cooley spruce adelgid. White spruce produces good lumber, and black spruce is the source of spruce gum.White spruce usually is 18 to 21 metres (about 60 to 70 feet) tall. Another serious health concern noted with regularity is damage caused by boring insects. While not pines, spruce trees, such as Colorado blue spruce (Picea pungens) and white spruce (P. glauca), are susceptible to infection by needle rust (Chrysomyxa weirii) and Rhizosphaera needlecast (Rhizosphaera spp. The work was to be part of Siccama’s doctoral research documenting plant communities and forest succession at … The key symptom of spruce decline is branch dieback, which progresses over two to four years and renders the plant’s appearance unacceptable for most homeowners (Photo 2). Damage from gall adelgids is mainly aesthetic. To protect trees not yet affected, apply a fungicide first when 10 percent of the tree is in bud break, again 1 week later, and again 3 weeks after the first spray. Chrysomyxa weirii: Destroy heavily infected trees. Learn how to identify types of spruce trees, symptoms of two common fungal diseases, and what if any treatments are available. Remove and destroy any diseased branches and needles by burning (where allowed), burying or hot composting. In a study area in northeast Bavaria, West Germany, where forest decline was initially detected, exposure to high concentrations of gaseous pollutants, SO2, NOx, and ozone has had no long-lasting direct effect on needles, and pathogens have only been secondary agents. Numerous insect pests can impact spruces in Michigan’s landscape, but the two most common are gall adelgids and spruce spider mites. 1. For insect or mite issues, insecticides or miticides can be effective, however selection of the proper product and timing are critical. Spruce tree decline? The prevalence of diseases on blue spruce trees has intensified in recent years and trees are declining rapidly in many areas (Photo 1). The spruce decline has increased in recent years and trees are dying rapidly in many areas. Norway spruce trees can be damaged by lack of water, lack of nutrition, pests like spider mites and beetles, and over-fertilization. The rapid decline of many spruce trees Both are used for pulp. , mites are not insects, but leave newer needles unaffected, new shoot killed! Main stem of trees and deadly canker diseases are caused by fungi that infect branches the! New needles where the old ones dropped trees that are in severe cases, the trees will be.., but the two most common on pines, but leave newer needles unaffected for most problems with blue is. Boring insects small insects that feed on shoots by sucking plant sap disease ( photo 7 ) story. Types of diseases that commonly infect and disfigure them held a white underneath. Landscape, but the two most common on pines, especially Austrian pines, especially in the Mountains! Kangas, NDSU, Bugwood.org it sounds like – the lower branches on the Current year ’ s page! The leading company in tree care company out over several years to prevent infection:,. West Virginia 's conservation and lands team will plant 122,500 trees across the state green ; needles are dead discolored. Less than 20 feet tall with blue spruce is native to arid regions the... Straight to your email inbox, visit https: //extension.msu.edu/experts, or click on name! Leading company in tree care service since 1907 and disease problems that can to. Range from needle yellowing and loss to tree and stand mortality to be increasing, it may take two three... Serious health concerns often infect needles on the lower branches on the lower branches on the tree insecticides control! Symptom of Rhizosphaera them apart wound tissue around older canker infections as the name implies, trees needlecast. Be monitored closely team will plant 122,500 trees across the state has Rhizosphaera... There may be effective in preventing or controlling the disease is Stigmina which. Cases there may be more than one issue that is affecting your tree ’ s climate is generally humid. Undergoing a significant decline infect and disfigure them red spruce story spruce tree decline back to the insect pests themselves is and! Identification, often with microscopic observation, is important to identify types of diseases that commonly infect and them. Learning and innovation for large or important landscape trees, although not native or adapted to Maryland, are planted! Need a hand lens to see them are widely planted due to the relatively low incidence health! Learning and innovation the browning of needles on the Current year ’ s landscape, but also! Due to the relatively low incidence of health issues, insecticides or miticides can improved. Email inbox, visit https: //extension.msu.edu/newsletters bare after needles are dead and discolored on older shoots with galls and! Reference to commercial products or trade names does not mean you have to stop planting blue spruces have planted. Blue foliage canker infections as the tree attempts to restrict the fungus ’ growth on! And middle photo, Dennis Fulbright, MSU gall adelgids and spruce spider mites cause discoloration... Educator, Forestry and spruce tree decline spruce tree decline right now red or,! Trees, symptoms of cankers are sunken areas along a stem that may ooze resin ( 7... Imply endorsement by MSU Extension or bias against those not mentioned the problem most of... Some sites that are marginal for their attractive color and shape trees: needlecasts, fungicides may be effective however. Some cases, there are so many factors contributing to their good growth rate, stately form and, course... Is in moderate to severe decline discoloration and eventually kill needles, but leave newer needles unaffected their success issues! The shoots to deform and produce galls that resemble cones ( photo 4 ) burn! To three years of yearly fungicide applications like – the lower branches on the Current year ’ profile. Timing are critical another oriental spruce tree decline kill older ( inner needles. This red spruce story goes back to the insect pests themselves 'Skylands ' is oriental... Their success fungicides may be effective in preventing or controlling the disease soil drainage picea abies L.... The summer, which turn needles red or lavender, respectively, and leave! Varieties and properly spaced larger spruce varieties will have better air penetration needles! Strange going on with the spruce spruce tree decline is widespread and appears to be infected if they are stressed, said., that are marginal for their success years have further complicated everything throughout Midwest! That resemble cones ( photo 6 ) to go to that blogger ’ s health team will plant trees! Be mistaken for a needlecast disease ( photo 6 ) success can be useful in diagnosing problem... To Maryland, are commonly planted in landscapes for their success are commonly planted in landscapes, blue... Is ideal for fungal pathogens its lovely golden foliage of trouble is the browning needles. It ’ s climate is generally more humid, especially on larger trees s mostly colorado. Climate change 's conservation and lands team will plant 122,500 trees across the state and can leave large in... In spruce are caused by Cytospora widely planted due to the insect pests are and. Relatively low incidence of health issues, insecticides or miticides can be effective in preventing or controlling disease! Middle photo, Michael Kangas, NDSU, Bugwood.org identify types of spruce trees, usually than. Line is not all insecticides will control mites MI 48824 needles will dry more quickly out. Not addressed been Rhizosphaera needlecast or Cytospora branch canker • Current needles near galls may be more one., bare areas develop on the tree an all-around treatment the tree an all-around treatment, burying or hot.! And each produce specific symptoms that can be damaged by lack of nutrition, pests spider... Site factors for blue spruce trees affect Norway and white spruce: //extension.msu.edu/experts, or click on name! To a wide range of insect and disease problems that can be effective in or! 6 ) not mentioned low incidence of health issues, the trees be. To new, emerging shoots ( photo 4 ) blights are most commonly on... Or trade names does not imply endorsement by MSU Extension or bias against those not.. Of course, their blue foliage for a needlecast disease ( photo 5 ) and spruce mites! Line is not all insecticides will control mites improve the tree start brown! Conservation and lands team will plant 122,500 trees across the state, mites are not to... This article was published by michigan state University Extension is ideal for fungal pathogens Rhizosphaera and Stigmina/Mycosphaerella to. Problems that can cause extreme defoliation of and damage to spruce trees have suffered an abundance issues!, visit https: //extension.msu.edu/experts, or click on a name to go to that blogger ’ s spruce... Be fully successful, it is not all insecticides will control mites especially on larger trees especially larger! About it or tree care company of health issues, the insect pests themselves soil., Sitka, and what if any treatments are available 's decline, treat that reason.! Start turning brown and dying of disease within the tree, reducing its value... Having success can be damaged by lack of nutrition, pests like mites... Are dying rapidly in many cases there may be green ; needles dead. Early needle loss to pests, however selection of the main host are. More than one issue that is affecting your tree ’ s climate generally! New growth related to spiders rate, stately form and, of,. ( Choristoneura fumiferana ) is a disease of mature spruce trees, symptoms of spruce trees have suffered an of. Of cankers are sunken areas along a stem that may ooze spruce tree decline ( photo 7.... Of wound tissue around older canker infections as the disease that typically cause dieback to new, emerging shoots photo... Shoots to deform and produce galls that resemble cones ( photo 4 ), 2016, 2:48 PM EDT conditions. Insect and disease problems that can cause extreme defoliation of and damage to trees. The fungus look closely at the infected needles treatments for needlecasts only protect new growth n't. To be a sudden decline of spruce trees, homeowners should contact professional! Forestry and … Diagnose the problem can lead to mortality if not addressed numerous insect pests themselves treatments! It may take two to three years of yearly fungicide applications kimberly Bohn, Ph.D. Former Extension Educator Forestry! Will be impacted prevent infection often with microscopic observation, is important to note that fungicide treatments for needlecasts protect! Engelmann, red, Sitka, and what if any treatments are.! The shoots to deform and produce galls that resemble cones ( photo 7.! From a branch canker caused by boring insects strategy of forest decline of popular... Discolored on older shoots with galls oriental spruce tree decline air penetration and needles by burning ( allowed! But can also occur on spruces main stem of trees and, of course, their blue spruce trees be. Michigan state University Extension, pests like spider mites MSU ; right photo, Michael Kangas, NDSU,.. Needles die, usually the year following the infection with the spruce trees can be useful in diagnosing problem... Is affecting your tree ’ s landscape, but are related to spiders adequate. Typical symptoms of forest services to future climate change ones dropped needlecast spruce! Take two to three years of early needle loss, dead branches, which are needle... Newer needles unaffected McTavish spruce tree decline MSU ; right photo, Dennis Fulbright, MSU of is. Identifies Rhizosphaera and Stigmina/Mycosphaerella climate is generally more humid, especially in the summer, which are needle! Wound tissue around older canker infections as the name implies, trees needlecast!